diff options
-rw-r--r-- | arch/arm/include/asm/probes.h | 2 | ||||
-rw-r--r-- | arch/arm/kernel/Makefile | 4 | ||||
-rw-r--r-- | arch/arm/kernel/kprobes-arm.c | 724 | ||||
-rw-r--r-- | arch/arm/kernel/kprobes-common.c | 425 | ||||
-rw-r--r-- | arch/arm/kernel/kprobes.h | 373 | ||||
-rw-r--r-- | arch/arm/kernel/probes-arm.c | 731 | ||||
-rw-r--r-- | arch/arm/kernel/probes-arm.h | 38 | ||||
-rw-r--r-- | arch/arm/kernel/probes.c | 443 | ||||
-rw-r--r-- | arch/arm/kernel/probes.h | 397 |
9 files changed, 1624 insertions, 1513 deletions
diff --git a/arch/arm/include/asm/probes.h b/arch/arm/include/asm/probes.h index 90c5f5485202..737a9b310efc 100644 --- a/arch/arm/include/asm/probes.h +++ b/arch/arm/include/asm/probes.h @@ -19,6 +19,8 @@ #ifndef _ASM_PROBES_H #define _ASM_PROBES_H +struct kprobe; + typedef void (kprobe_insn_handler_t)(struct kprobe *, struct pt_regs *); typedef unsigned long (kprobe_check_cc)(unsigned long); typedef void (kprobe_insn_singlestep_t)(struct kprobe *, struct pt_regs *); diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile index a30fc9be9e9e..4c8b13e64280 100644 --- a/arch/arm/kernel/Makefile +++ b/arch/arm/kernel/Makefile @@ -50,11 +50,11 @@ obj-$(CONFIG_DYNAMIC_FTRACE) += ftrace.o insn.o obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += ftrace.o insn.o obj-$(CONFIG_JUMP_LABEL) += jump_label.o insn.o patch.o obj-$(CONFIG_KEXEC) += machine_kexec.o relocate_kernel.o -obj-$(CONFIG_KPROBES) += kprobes.o kprobes-common.o patch.o +obj-$(CONFIG_KPROBES) += probes.o kprobes.o kprobes-common.o patch.o ifdef CONFIG_THUMB2_KERNEL obj-$(CONFIG_KPROBES) += kprobes-thumb.o else -obj-$(CONFIG_KPROBES) += kprobes-arm.o +obj-$(CONFIG_KPROBES) += kprobes-arm.o probes-arm.o endif obj-$(CONFIG_ARM_KPROBES_TEST) += test-kprobes.o test-kprobes-objs := kprobes-test.o diff --git a/arch/arm/kernel/kprobes-arm.c b/arch/arm/kernel/kprobes-arm.c index 8a30c89da70e..a1d0a8f00f9e 100644 --- a/arch/arm/kernel/kprobes-arm.c +++ b/arch/arm/kernel/kprobes-arm.c @@ -60,13 +60,10 @@ #include <linux/kernel.h> #include <linux/kprobes.h> -#include <linux/module.h> +#include <linux/ptrace.h> #include "kprobes.h" - -#define sign_extend(x, signbit) ((x) | (0 - ((x) & (1 << (signbit))))) - -#define branch_displacement(insn) sign_extend(((insn) & 0xffffff) << 2, 25) +#include "probes-arm.h" #if __LINUX_ARM_ARCH__ >= 6 #define BLX(reg) "blx "reg" \n\t" @@ -75,88 +72,8 @@ "mov pc, "reg" \n\t" #endif -/* - * To avoid the complications of mimicing single-stepping on a - * processor without a Next-PC or a single-step mode, and to - * avoid having to deal with the side-effects of boosting, we - * simulate or emulate (almost) all ARM instructions. - * - * "Simulation" is where the instruction's behavior is duplicated in - * C code. "Emulation" is where the original instruction is rewritten - * and executed, often by altering its registers. - * - * By having all behavior of the kprobe'd instruction completed before - * returning from the kprobe_handler(), all locks (scheduler and - * interrupt) can safely be released. There is no need for secondary - * breakpoints, no race with MP or preemptable kernels, nor having to - * clean up resources counts at a later time impacting overall system - * performance. By rewriting the instruction, only the minimum registers - * need to be loaded and saved back optimizing performance. - * - * Calling the insnslot_*_rwflags version of a function doesn't hurt - * anything even when the CPSR flags aren't updated by the - * instruction. It's just a little slower in return for saving - * a little space by not having a duplicate function that doesn't - * update the flags. (The same optimization can be said for - * instructions that do or don't perform register writeback) - * Also, instructions can either read the flags, only write the - * flags, or read and write the flags. To save combinations - * rather than for sheer performance, flag functions just assume - * read and write of flags. - */ - -static void __kprobes simulate_bbl(struct kprobe *p, struct pt_regs *regs) -{ - kprobe_opcode_t insn = p->opcode; - long iaddr = (long)p->addr; - int disp = branch_displacement(insn); - - if (insn & (1 << 24)) - regs->ARM_lr = iaddr + 4; - - regs->ARM_pc = iaddr + 8 + disp; -} - -static void __kprobes simulate_blx1(struct kprobe *p, struct pt_regs *regs) -{ - kprobe_opcode_t insn = p->opcode; - long iaddr = (long)p->addr; - int disp = branch_displacement(insn); - - regs->ARM_lr = iaddr + 4; - regs->ARM_pc = iaddr + 8 + disp + ((insn >> 23) & 0x2); - regs->ARM_cpsr |= PSR_T_BIT; -} -static void __kprobes simulate_blx2bx(struct kprobe *p, struct pt_regs *regs) -{ - kprobe_opcode_t insn = p->opcode; - int rm = insn & 0xf; - long rmv = regs->uregs[rm]; - - if (insn & (1 << 5)) - regs->ARM_lr = (long)p->addr + 4; - - regs->ARM_pc = rmv & ~0x1; - regs->ARM_cpsr &= ~PSR_T_BIT; - if (rmv & 0x1) - regs->ARM_cpsr |= PSR_T_BIT; -} - -static void __kprobes simulate_mrs(struct kprobe *p, struct pt_regs *regs) -{ - kprobe_opcode_t insn = p->opcode; - int rd = (insn >> 12) & 0xf; - unsigned long mask = 0xf8ff03df; /* Mask out execution state */ - regs->uregs[rd] = regs->ARM_cpsr & mask; -} - -static void __kprobes simulate_mov_ipsp(struct kprobe *p, struct pt_regs *regs) -{ - regs->uregs[12] = regs->uregs[13]; -} - -static void __kprobes +void __kprobes emulate_ldrdstrd(struct kprobe *p, struct pt_regs *regs) { kprobe_opcode_t insn = p->opcode; @@ -185,7 +102,7 @@ emulate_ldrdstrd(struct kprobe *p, struct pt_regs *regs) regs->uregs[rn] = rnv; } -static void __kprobes +void __kprobes emulate_ldr(struct kprobe *p, struct pt_regs *regs) { kprobe_opcode_t insn = p->opcode; @@ -215,7 +132,7 @@ emulate_ldr(struct kprobe *p, struct pt_regs *regs) regs->uregs[rn] = rnv; } -static void __kprobes +void __kprobes emulate_str(struct kprobe *p, struct pt_regs *regs) { kprobe_opcode_t insn = p->opcode; @@ -242,7 +159,7 @@ emulate_str(struct kprobe *p, struct pt_regs *regs) regs->uregs[rn] = rnv; } -static void __kprobes +void __kprobes emulate_rd12rn16rm0rs8_rwflags(struct kprobe *p, struct pt_regs *regs) { kprobe_opcode_t insn = p->opcode; @@ -277,7 +194,7 @@ emulate_rd12rn16rm0rs8_rwflags(struct kprobe *p, struct pt_regs *regs) regs->ARM_cpsr = (regs->ARM_cpsr & ~APSR_MASK) | (cpsr & APSR_MASK); } -static void __kprobes +void __kprobes emulate_rd12rn16rm0_rwflags_nopc(struct kprobe *p, struct pt_regs *regs) { kprobe_opcode_t insn = p->opcode; @@ -304,7 +221,7 @@ emulate_rd12rn16rm0_rwflags_nopc(struct kprobe *p, struct pt_regs *regs) regs->ARM_cpsr = (regs->ARM_cpsr & ~APSR_MASK) | (cpsr & APSR_MASK); } -static void __kprobes +void __kprobes emulate_rd16rn12rm0rs8_rwflags_nopc(struct kprobe *p, struct pt_regs *regs) { kprobe_opcode_t insn = p->opcode; @@ -333,7 +250,7 @@ emulate_rd16rn12rm0rs8_rwflags_nopc(struct kprobe *p, struct pt_regs *regs) regs->ARM_cpsr = (regs->ARM_cpsr & ~APSR_MASK) | (cpsr & APSR_MASK); } -static void __kprobes +void __kprobes emulate_rd12rm0_noflags_nopc(struct kprobe *p, struct pt_regs *regs) { kprobe_opcode_t insn = p->opcode; @@ -353,7 +270,7 @@ emulate_rd12rm0_noflags_nopc(struct kprobe *p, struct pt_regs *regs) regs->uregs[rd] = rdv; } -static void __kprobes +void __kprobes emulate_rdlo12rdhi16rn0rm8_rwflags_nopc(struct kprobe *p, struct pt_regs *regs) { kprobe_opcode_t insn = p->opcode; @@ -382,624 +299,3 @@ emulate_rdlo12rdhi16rn0rm8_rwflags_nopc(struct kprobe *p, struct pt_regs *regs) regs->uregs[rdhi] = rdhiv; regs->ARM_cpsr = (regs->ARM_cpsr & ~APSR_MASK) | (cpsr & APSR_MASK); } - -/* - * For the instruction masking and comparisons in all the "space_*" - * functions below, Do _not_ rearrange the order of tests unless - * you're very, very sure of what you are doing. For the sake of - * efficiency, the masks for some tests sometimes assume other test - * have been done prior to them so the number of patterns to test - * for an instruction set can be as broad as possible to reduce the - * number of tests needed. - */ - -static const union decode_item arm_1111_table[] = { - /* Unconditional instructions */ - - /* memory hint 1111 0100 x001 xxxx xxxx xxxx xxxx xxxx */ - /* PLDI (immediate) 1111 0100 x101 xxxx xxxx xxxx xxxx xxxx */ - /* PLDW (immediate) 1111 0101 x001 xxxx xxxx xxxx xxxx xxxx */ - /* PLD (immediate) 1111 0101 x101 xxxx xxxx xxxx xxxx xxxx */ - DECODE_SIMULATE (0xfe300000, 0xf4100000, kprobe_simulate_nop), - - /* memory hint 1111 0110 x001 xxxx xxxx xxxx xxx0 xxxx */ - /* PLDI (register) 1111 0110 x101 xxxx xxxx xxxx xxx0 xxxx */ - /* PLDW (register) 1111 0111 x001 xxxx xxxx xxxx xxx0 xxxx */ - /* PLD (register) 1111 0111 x101 xxxx xxxx xxxx xxx0 xxxx */ - DECODE_SIMULATE (0xfe300010, 0xf6100000, kprobe_simulate_nop), - - /* BLX (immediate) 1111 101x xxxx xxxx xxxx xxxx xxxx xxxx */ - DECODE_SIMULATE (0xfe000000, 0xfa000000, simulate_blx1), - - /* CPS 1111 0001 0000 xxx0 xxxx xxxx xx0x xxxx */ - /* SETEND 1111 0001 0000 0001 xxxx xxxx 0000 xxxx */ - /* SRS 1111 100x x1x0 xxxx xxxx xxxx xxxx xxxx */ - /* RFE 1111 100x x0x1 xxxx xxxx xxxx xxxx xxxx */ - - /* Coprocessor instructions... */ - /* MCRR2 1111 1100 0100 xxxx xxxx xxxx xxxx xxxx */ - /* MRRC2 1111 1100 0101 xxxx xxxx xxxx xxxx xxxx */ - /* LDC2 1111 110x xxx1 xxxx xxxx xxxx xxxx xxxx */ - /* STC2 1111 110x xxx0 xxxx xxxx xxxx xxxx xxxx */ - /* CDP2 1111 1110 xxxx xxxx xxxx xxxx xxx0 xxxx */ - /* MCR2 1111 1110 xxx0 xxxx xxxx xxxx xxx1 xxxx */ - /* MRC2 1111 1110 xxx1 xxxx xxxx xxxx xxx1 xxxx */ - - /* Other unallocated instructions... */ - DECODE_END -}; - -static const union decode_item arm_cccc_0001_0xx0____0xxx_table[] = { - /* Miscellaneous instructions */ - - /* MRS cpsr cccc 0001 0000 xxxx xxxx xxxx 0000 xxxx */ - DECODE_SIMULATEX(0x0ff000f0, 0x01000000, simulate_mrs, - REGS(0, NOPC, 0, 0, 0)), - - /* BX cccc 0001 0010 xxxx xxxx xxxx 0001 xxxx */ - DECODE_SIMULATE (0x0ff000f0, 0x01200010, simulate_blx2bx), - - /* BLX (register) cccc 0001 0010 xxxx xxxx xxxx 0011 xxxx */ - DECODE_SIMULATEX(0x0ff000f0, 0x01200030, simulate_blx2bx, - REGS(0, 0, 0, 0, NOPC)), - - /* CLZ cccc 0001 0110 xxxx xxxx xxxx 0001 xxxx */ - DECODE_EMULATEX (0x0ff000f0, 0x01600010, emulate_rd12rm0_noflags_nopc, - REGS(0, NOPC, 0, 0, NOPC)), - - /* QADD cccc 0001 0000 xxxx xxxx xxxx 0101 xxxx */ - /* QSUB cccc 0001 0010 xxxx xxxx xxxx 0101 xxxx */ - /* QDADD cccc 0001 0100 xxxx xxxx xxxx 0101 xxxx */ - /* QDSUB cccc 0001 0110 xxxx xxxx xxxx 0101 xxxx */ - DECODE_EMULATEX (0x0f9000f0, 0x01000050, emulate_rd12rn16rm0_rwflags_nopc, - REGS(NOPC, NOPC, 0, 0, NOPC)), - - /* BXJ cccc 0001 0010 xxxx xxxx xxxx 0010 xxxx */ - /* MSR cccc 0001 0x10 xxxx xxxx xxxx 0000 xxxx */ - /* MRS spsr cccc 0001 0100 xxxx xxxx xxxx 0000 xxxx */ - /* BKPT 1110 0001 0010 xxxx xxxx xxxx 0111 xxxx */ - /* SMC cccc 0001 0110 xxxx xxxx xxxx 0111 xxxx */ - /* And unallocated instructions... */ - DECODE_END -}; - -static const union decode_item arm_cccc_0001_0xx0____1xx0_table[] = { - /* Halfword multiply and multiply-accumulate */ - - /* SMLALxy cccc 0001 0100 xxxx xxxx xxxx 1xx0 xxxx */ - DECODE_EMULATEX (0x0ff00090, 0x01400080, emulate_rdlo12rdhi16rn0rm8_rwflags_nopc, - REGS(NOPC, NOPC, NOPC, 0, NOPC)), - - /* SMULWy cccc 0001 0010 xxxx xxxx xxxx 1x10 xxxx */ - DECODE_OR (0x0ff000b0, 0x012000a0), - /* SMULxy cccc 0001 0110 xxxx xxxx xxxx 1xx0 xxxx */ - DECODE_EMULATEX (0x0ff00090, 0x01600080, emulate_rd16rn12rm0rs8_rwflags_nopc, - REGS(NOPC, 0, NOPC, 0, NOPC)), - - /* SMLAxy cccc 0001 0000 xxxx xxxx xxxx 1xx0 xxxx */ - DECODE_OR (0x0ff00090, 0x01000080), - /* SMLAWy cccc 0001 0010 xxxx xxxx xxxx 1x00 xxxx */ - DECODE_EMULATEX (0x0ff000b0, 0x01200080, emulate_rd16rn12rm0rs8_rwflags_nopc, - REGS(NOPC, NOPC, NOPC, 0, NOPC)), - - DECODE_END -}; - -static const union decode_item arm_cccc_0000_____1001_table[] = { - /* Multiply and multiply-accumulate */ - - /* MUL cccc 0000 0000 xxxx xxxx xxxx 1001 xxxx */ - /* MULS cccc 0000 0001 xxxx xxxx xxxx 1001 xxxx */ - DECODE_EMULATEX (0x0fe000f0, 0x00000090, emulate_rd16rn12rm0rs8_rwflags_nopc, - REGS(NOPC, 0, NOPC, 0, NOPC)), - - /* MLA cccc 0000 0010 xxxx xxxx xxxx 1001 xxxx */ - /* MLAS cccc 0000 0011 xxxx xxxx xxxx 1001 xxxx */ - DECODE_OR (0x0fe000f0, 0x00200090), - /* MLS cccc 0000 0110 xxxx xxxx xxxx 1001 xxxx */ - DECODE_EMULATEX (0x0ff000f0, 0x00600090, emulate_rd16rn12rm0rs8_rwflags_nopc, - REGS(NOPC, NOPC, NOPC, 0, NOPC)), - - /* UMAAL cccc 0000 0100 xxxx xxxx xxxx 1001 xxxx */ - DECODE_OR (0x0ff000f0, 0x00400090), - /* UMULL cccc 0000 1000 xxxx xxxx xxxx 1001 xxxx */ - /* UMULLS cccc 0000 1001 xxxx xxxx xxxx 1001 xxxx */ - /* UMLAL cccc 0000 1010 xxxx xxxx xxxx 1001 xxxx */ - /* UMLALS cccc 0000 1011 xxxx xxxx xxxx 1001 xxxx */ - /* SMULL cccc 0000 1100 xxxx xxxx xxxx 1001 xxxx */ - /* SMULLS cccc 0000 1101 xxxx xxxx xxxx 1001 xxxx */ - /* SMLAL cccc 0000 1110 xxxx xxxx xxxx 1001 xxxx */ - /* SMLALS cccc 0000 1111 xxxx xxxx xxxx 1001 xxxx */ - DECODE_EMULATEX (0x0f8000f0, 0x00800090, emulate_rdlo12rdhi16rn0rm8_rwflags_nopc, - REGS(NOPC, NOPC, NOPC, 0, NOPC)), - - DECODE_END -}; - -static const union decode_item arm_cccc_0001_____1001_table[] = { - /* Synchronization primitives */ - -#if __LINUX_ARM_ARCH__ < 6 - /* Deprecated on ARMv6 and may be UNDEFINED on v7 */ - /* SMP/SWPB cccc 0001 0x00 xxxx xxxx xxxx 1001 xxxx */ - DECODE_EMULATEX (0x0fb000f0, 0x01000090, emulate_rd12rn16rm0_rwflags_nopc, - REGS(NOPC, NOPC, 0, 0, NOPC)), -#endif - /* LDREX/STREX{,D,B,H} cccc 0001 1xxx xxxx xxxx xxxx 1001 xxxx */ - /* And unallocated instructions... */ - DECODE_END -}; - -static const union decode_item arm_cccc_000x_____1xx1_table[] = { - /* Extra load/store instructions */ - - /* STRHT cccc 0000 xx10 xxxx xxxx xxxx 1011 xxxx */ - /* ??? cccc 0000 xx10 xxxx xxxx xxxx 11x1 xxxx */ - /* LDRHT cccc 0000 xx11 xxxx xxxx xxxx 1011 xxxx */ - /* LDRSBT cccc 0000 xx11 xxxx xxxx xxxx 1101 xxxx */ - /* LDRSHT cccc 0000 xx11 xxxx xxxx xxxx 1111 xxxx */ - DECODE_REJECT (0x0f200090, 0x00200090), - - /* LDRD/STRD lr,pc,{... cccc 000x x0x0 xxxx 111x xxxx 1101 xxxx */ - DECODE_REJECT (0x0e10e0d0, 0x0000e0d0), - - /* LDRD (register) cccc 000x x0x0 xxxx xxxx xxxx 1101 xxxx */ - /* STRD (register) cccc 000x x0x0 xxxx xxxx xxxx 1111 xxxx */ - DECODE_EMULATEX (0x0e5000d0, 0x000000d0, emulate_ldrdstrd, - REGS(NOPCWB, NOPCX, 0, 0, NOPC)), - - /* LDRD (immediate) cccc 000x x1x0 xxxx xxxx xxxx 1101 xxxx */ - /* STRD (immediate) cccc 000x x1x0 xxxx xxxx xxxx 1111 xxxx */ - DECODE_EMULATEX (0x0e5000d0, 0x004000d0, emulate_ldrdstrd, - REGS(NOPCWB, NOPCX, 0, 0, 0)), - - /* STRH (register) cccc 000x x0x0 xxxx xxxx xxxx 1011 xxxx */ - DECODE_EMULATEX (0x0e5000f0, 0x000000b0, emulate_str, - REGS(NOPCWB, NOPC, 0, 0, NOPC)), - - /* LDRH (register) cccc 000x x0x1 xxxx xxxx xxxx 1011 xxxx */ - /* LDRSB (register) cccc 000x x0x1 xxxx xxxx xxxx 1101 xxxx */ - /* LDRSH (register) cccc 000x x0x1 xxxx xxxx xxxx 1111 xxxx */ - DECODE_EMULATEX (0x0e500090, 0x00100090, emulate_ldr, - REGS(NOPCWB, NOPC, 0, 0, NOPC)), - - /* STRH (immediate) cccc 000x x1x0 xxxx xxxx xxxx 1011 xxxx */ - DECODE_EMULATEX (0x0e5000f0, 0x004000b0, emulate_str, - REGS(NOPCWB, NOPC, 0, 0, 0)), - - /* LDRH (immediate) cccc 000x x1x1 xxxx xxxx xxxx 1011 xxxx */ - /* LDRSB (immediate) cccc 000x x1x1 xxxx xxxx xxxx 1101 xxxx */ - /* LDRSH (immediate) cccc 000x x1x1 xxxx xxxx xxxx 1111 xxxx */ - DECODE_EMULATEX (0x0e500090, 0x00500090, emulate_ldr, - REGS(NOPCWB, NOPC, 0, 0, 0)), - - DECODE_END -}; - -static const union decode_item arm_cccc_000x_table[] = { - /* Data-processing (register) */ - - /* <op>S PC, ... cccc 000x xxx1 xxxx 1111 xxxx xxxx xxxx */ - DECODE_REJECT (0x0e10f000, 0x0010f000), - - /* MOV IP, SP 1110 0001 1010 0000 1100 0000 0000 1101 */ - DECODE_SIMULATE (0xffffffff, 0xe1a0c00d, simulate_mov_ipsp), - - /* TST (register) cccc 0001 0001 xxxx xxxx xxxx xxx0 xxxx */ - /* TEQ (register) cccc 0001 0011 xxxx xxxx xxxx xxx0 xxxx */ - /* CMP (register) cccc 0001 0101 xxxx xxxx xxxx xxx0 xxxx */ - /* CMN (register) cccc 0001 0111 xxxx xxxx xxxx xxx0 xxxx */ - DECODE_EMULATEX (0x0f900010, 0x01100000, emulate_rd12rn16rm0rs8_rwflags, - REGS(ANY, 0, 0, 0, ANY)), - - /* MOV (register) cccc 0001 101x xxxx xxxx xxxx xxx0 xxxx */ - /* MVN (register) cccc 0001 111x xxxx xxxx xxxx xxx0 xxxx */ - DECODE_EMULATEX (0x0fa00010, 0x01a00000, emulate_rd12rn16rm0rs8_rwflags, - REGS(0, ANY, 0, 0, ANY)), - - /* AND (register) cccc 0000 000x xxxx xxxx xxxx xxx0 xxxx */ - /* EOR (register) cccc 0000 001x xxxx xxxx xxxx xxx0 xxxx */ - /* SUB (register) cccc 0000 010x xxxx xxxx xxxx xxx0 xxxx */ - /* RSB (register) cccc 0000 011x xxxx xxxx xxxx xxx0 xxxx */ - /* ADD (register) cccc 0000 100x xxxx xxxx xxxx xxx0 xxxx */ - /* ADC (register) cccc 0000 101x xxxx xxxx xxxx xxx0 xxxx */ - /* SBC (register) cccc 0000 110x xxxx xxxx xxxx xxx0 xxxx */ - /* RSC (register) cccc 0000 111x xxxx xxxx xxxx xxx0 xxxx */ - /* ORR (register) cccc 0001 100x xxxx xxxx xxxx xxx0 xxxx */ - /* BIC (register) cccc 0001 110x xxxx xxxx xxxx xxx0 xxxx */ - DECODE_EMULATEX (0x0e000010, 0x00000000, emulate_rd12rn16rm0rs8_rwflags, - REGS(ANY, ANY, 0, 0, ANY)), - - /* TST (reg-shift reg) cccc 0001 0001 xxxx xxxx xxxx 0xx1 xxxx */ - /* TEQ (reg-shift reg) cccc 0001 0011 xxxx xxxx xxxx 0xx1 xxxx */ - /* CMP (reg-shift reg) cccc 0001 0101 xxxx xxxx xxxx 0xx1 xxxx */ - /* CMN (reg-shift reg) cccc 0001 0111 xxxx xxxx xxxx 0xx1 xxxx */ - DECODE_EMULATEX (0x0f900090, 0x01100010, emulate_rd12rn16rm0rs8_rwflags, - REGS(ANY, 0, NOPC, 0, ANY)), - - /* MOV (reg-shift reg) cccc 0001 101x xxxx xxxx xxxx 0xx1 xxxx */ - /* MVN (reg-shift reg) cccc 0001 111x xxxx xxxx xxxx 0xx1 xxxx */ - DECODE_EMULATEX (0x0fa00090, 0x01a00010, emulate_rd12rn16rm0rs8_rwflags, - REGS(0, ANY, NOPC, 0, ANY)), - - /* AND (reg-shift reg) cccc 0000 000x xxxx xxxx xxxx 0xx1 xxxx */ - /* EOR (reg-shift reg) cccc 0000 001x xxxx xxxx xxxx 0xx1 xxxx */ - /* SUB (reg-shift reg) cccc 0000 010x xxxx xxxx xxxx 0xx1 xxxx */ - /* RSB (reg-shift reg) cccc 0000 011x xxxx xxxx xxxx 0xx1 xxxx */ - /* ADD (reg-shift reg) cccc 0000 100x xxxx xxxx xxxx 0xx1 xxxx */ - /* ADC (reg-shift reg) cccc 0000 101x xxxx xxxx xxxx 0xx1 xxxx */ - /* SBC (reg-shift reg) cccc 0000 110x xxxx xxxx xxxx 0xx1 xxxx */ - /* RSC (reg-shift reg) cccc 0000 111x xxxx xxxx xxxx 0xx1 xxxx */ - /* ORR (reg-shift reg) cccc 0001 100x xxxx xxxx xxxx 0xx1 xxxx */ - /* BIC (reg-shift reg) cccc 0001 110x xxxx xxxx xxxx 0xx1 xxxx */ - DECODE_EMULATEX (0x0e000090, 0x00000010, emulate_rd12rn16rm0rs8_rwflags, - REGS(ANY, ANY, NOPC, 0, ANY)), - - DECODE_END -}; - -static const union decode_item arm_cccc_001x_table[] = { - /* Data-processing (immediate) */ - - /* MOVW cccc 0011 0000 xxxx xxxx xxxx xxxx xxxx */ - /* MOVT cccc 0011 0100 xxxx xxxx xxxx xxxx xxxx */ - DECODE_EMULATEX (0x0fb00000, 0x03000000, emulate_rd12rm0_noflags_nopc, - REGS(0, NOPC, 0, 0, 0)), - - /* YIELD cccc 0011 0010 0000 xxxx xxxx 0000 0001 */ - DECODE_OR (0x0fff00ff, 0x03200001), - /* SEV cccc 0011 0010 0000 xxxx xxxx 0000 0100 */ - DECODE_EMULATE (0x0fff00ff, 0x03200004, kprobe_emulate_none), - /* NOP cccc 0011 0010 0000 xxxx xxxx 0000 0000 */ - /* WFE cccc 0011 0010 0000 xxxx xxxx 0000 0010 */ - /* WFI cccc 0011 0010 0000 xxxx xxxx 0000 0011 */ - DECODE_SIMULATE (0x0fff00fc, 0x03200000, kprobe_simulate_nop), - /* DBG cccc 0011 0010 0000 xxxx xxxx ffff xxxx */ - /* unallocated hints cccc 0011 0010 0000 xxxx xxxx xxxx xxxx */ - /* MSR (immediate) cccc 0011 0x10 xxxx xxxx xxxx xxxx xxxx */ - DECODE_REJECT (0x0fb00000, 0x03200000), - - /* <op>S PC, ... cccc 001x xxx1 xxxx 1111 xxxx xxxx xxxx */ - DECODE_REJECT (0x0e10f000, 0x0210f000), - - /* TST (immediate) cccc 0011 0001 xxxx xxxx xxxx xxxx xxxx */ - /* TEQ (immediate) cccc 0011 0011 xxxx xxxx xxxx xxxx xxxx */ - /* CMP (immediate) cccc 0011 0101 xxxx xxxx xxxx xxxx xxxx */ - /* CMN (immediate) cccc 0011 0111 xxxx xxxx xxxx xxxx xxxx */ - DECODE_EMULATEX (0x0f900000, 0x03100000, emulate_rd12rn16rm0rs8_rwflags, - REGS(ANY, 0, 0, 0, 0)), - - /* MOV (immediate) cccc 0011 101x xxxx xxxx xxxx xxxx xxxx */ - /* MVN (immediate) cccc 0011 111x xxxx xxxx xxxx xxxx xxxx */ - DECODE_EMULATEX (0x0fa00000, 0x03a00000, emulate_rd12rn16rm0rs8_rwflags, - REGS(0, ANY, 0, 0, 0)), - - /* AND (immediate) cccc 0010 000x xxxx xxxx xxxx xxxx xxxx */ - /* EOR (immediate) cccc 0010 001x xxxx xxxx xxxx xxxx xxxx */ - /* SUB (immediate) cccc 0010 010x xxxx xxxx xxxx xxxx xxxx */ - /* RSB (immediate) cccc 0010 011x xxxx xxxx xxxx xxxx xxxx */ - /* ADD (immediate) cccc 0010 100x xxxx xxxx xxxx xxxx xxxx */ - /* ADC (immediate) cccc 0010 101x xxxx xxxx xxxx xxxx xxxx */ - /* SBC (immediate) cccc 0010 110x xxxx xxxx xxxx xxxx xxxx */ - /* RSC (immediate) cccc 0010 111x xxxx xxxx xxxx xxxx xxxx */ - /* ORR (immediate) cccc 0011 100x xxxx xxxx xxxx xxxx xxxx */ - /* BIC (immediate) cccc 0011 110x xxxx xxxx xxxx xxxx xxxx */ - DECODE_EMULATEX (0x0e000000, 0x02000000, emulate_rd12rn16rm0rs8_rwflags, - REGS(ANY, ANY, 0, 0, 0)), - - DECODE_END -}; - -static const union decode_item arm_cccc_0110_____xxx1_table[] = { - /* Media instructions */ - - /* SEL cccc 0110 1000 xxxx xxxx xxxx 1011 xxxx */ - DECODE_EMULATEX (0x0ff000f0, 0x068000b0, emulate_rd12rn16rm0_rwflags_nopc, - REGS(NOPC, NOPC, 0, 0, NOPC)), - - /* SSAT cccc 0110 101x xxxx xxxx xxxx xx01 xxxx */ - /* USAT cccc 0110 111x xxxx xxxx xxxx xx01 xxxx */ - DECODE_OR(0x0fa00030, 0x06a00010), - /* SSAT16 cccc 0110 1010 xxxx xxxx xxxx 0011 xxxx */ - /* USAT16 cccc 0110 1110 xxxx xxxx xxxx 0011 xxxx */ - DECODE_EMULATEX (0x0fb000f0, 0x06a00030, emulate_rd12rn16rm0_rwflags_nopc, - REGS(0, NOPC, 0, 0, NOPC)), - - /* REV cccc 0110 1011 xxxx xxxx xxxx 0011 xxxx */ - /* REV16 cccc 0110 1011 xxxx xxxx xxxx 1011 xxxx */ - /* RBIT cccc 0110 1111 xxxx xxxx xxxx 0011 xxxx */ - /* REVSH cccc 0110 1111 xxxx xxxx xxxx 1011 xxxx */ - DECODE_EMULATEX (0x0fb00070, 0x06b00030, emulate_rd12rm0_noflags_nopc, - REGS(0, NOPC, 0, 0, NOPC)), - - /* ??? cccc 0110 0x00 xxxx xxxx xxxx xxx1 xxxx */ - DECODE_REJECT (0x0fb00010, 0x06000010), - /* ??? cccc 0110 0xxx xxxx xxxx xxxx 1011 xxxx */ - DECODE_REJECT (0x0f8000f0, 0x060000b0), - /* ??? cccc 0110 0xxx xxxx xxxx xxxx 1101 xxxx */ - DECODE_REJECT (0x0f8000f0, 0x060000d0), - /* SADD16 cccc 0110 0001 xxxx xxxx xxxx 0001 xxxx */ - /* SADDSUBX cccc 0110 0001 xxxx xxxx xxxx 0011 xxxx */ - /* SSUBADDX cccc 0110 0001 xxxx xxxx xxxx 0101 xxxx */ - /* SSUB16 cccc 0110 0001 xxxx xxxx xxxx 0111 xxxx */ - /* SADD8 cccc 0110 0001 xxxx xxxx xxxx 1001 xxxx */ - /* SSUB8 cccc 0110 0001 xxxx xxxx xxxx 1111 xxxx */ - /* QADD16 cccc 0110 0010 xxxx xxxx xxxx 0001 xxxx */ - /* QADDSUBX cccc 0110 0010 xxxx xxxx xxxx 0011 xxxx */ - /* QSUBADDX cccc 0110 0010 xxxx xxxx xxxx 0101 xxxx */ - /* QSUB16 cccc 0110 0010 xxxx xxxx xxxx 0111 xxxx */ - /* QADD8 cccc 0110 0010 xxxx xxxx xxxx 1001 xxxx */ - /* QSUB8 cccc 0110 0010 xxxx xxxx xxxx 1111 xxxx */ - /* SHADD16 cccc 0110 0011 xxxx xxxx xxxx 0001 xxxx */ - /* SHADDSUBX cccc 0110 0011 xxxx xxxx xxxx 0011 xxxx */ - /* SHSUBADDX cccc 0110 0011 xxxx xxxx xxxx 0101 xxxx */ - /* SHSUB16 cccc 0110 0011 xxxx xxxx xxxx 0111 xxxx */ - /* SHADD8 cccc 0110 0011 xxxx xxxx xxxx 1001 xxxx */ - /* SHSUB8 cccc 0110 0011 xxxx xxxx xxxx 1111 xxxx */ - /* UADD16 cccc 0110 0101 xxxx xxxx xxxx 0001 xxxx */ - /* UADDSUBX cccc 0110 0101 xxxx xxxx xxxx 0011 xxxx */ - /* USUBADDX cccc 0110 0101 xxxx xxxx xxxx 0101 xxxx */ - /* USUB16 cccc 0110 0101 xxxx xxxx xxxx 0111 xxxx */ - /* UADD8 cccc 0110 0101 xxxx xxxx xxxx 1001 xxxx */ - /* USUB8 cccc 0110 0101 xxxx xxxx xxxx 1111 xxxx */ - /* UQADD16 cccc 0110 0110 xxxx xxxx xxxx 0001 xxxx */ - /* UQADDSUBX cccc 0110 0110 xxxx xxxx xxxx 0011 xxxx */ - /* UQSUBADDX cccc 0110 0110 xxxx xxxx xxxx 0101 xxxx */ - /* UQSUB16 cccc 0110 0110 xxxx xxxx xxxx 0111 xxxx */ - /* UQADD8 cccc 0110 0110 xxxx xxxx xxxx 1001 xxxx */ - /* UQSUB8 cccc 0110 0110 xxxx xxxx xxxx 1111 xxxx */ - /* UHADD16 cccc 0110 0111 xxxx xxxx xxxx 0001 xxxx */ - /* UHADDSUBX cccc 0110 0111 xxxx xxxx xxxx 0011 xxxx */ - /* UHSUBADDX cccc 0110 0111 xxxx xxxx xxxx 0101 xxxx */ - /* UHSUB16 cccc 0110 0111 xxxx xxxx xxxx 0111 xxxx */ - /* UHADD8 cccc 0110 0111 xxxx xxxx xxxx 1001 xxxx */ - /* UHSUB8 cccc 0110 0111 xxxx xxxx xxxx 1111 xxxx */ - DECODE_EMULATEX (0x0f800010, 0x06000010, emulate_rd12rn16rm0_rwflags_nopc, - REGS(NOPC, NOPC, 0, 0, NOPC)), - - /* PKHBT cccc 0110 1000 xxxx xxxx xxxx x001 xxxx */ - /* PKHTB cccc 0110 1000 xxxx xxxx xxxx x101 xxxx */ - DECODE_EMULATEX (0x0ff00030, 0x06800010, emulate_rd12rn16rm0_rwflags_nopc, - REGS(NOPC, NOPC, 0, 0, NOPC)), - - /* ??? cccc 0110 1001 xxxx xxxx xxxx 0111 xxxx */ - /* ??? cccc 0110 1101 xxxx xxxx xxxx 0111 xxxx */ - DECODE_REJECT (0x0fb000f0, 0x06900070), - - /* SXTB16 cccc 0110 1000 1111 xxxx xxxx 0111 xxxx */ - /* SXTB cccc 0110 1010 1111 xxxx xxxx 0111 xxxx */ - /* SXTH cccc 0110 1011 1111 xxxx xxxx 0111 xxxx */ - /* UXTB16 cccc 0110 1100 1111 xxxx xxxx 0111 xxxx */ - /* UXTB cccc 0110 1110 1111 xxxx xxxx 0111 xxxx */ - /* UXTH cccc 0110 1111 1111 xxxx xxxx 0111 xxxx */ - DECODE_EMULATEX (0x0f8f00f0, 0x068f0070, emulate_rd12rm0_noflags_nopc, - REGS(0, NOPC, 0, 0, NOPC)), - - /* SXTAB16 cccc 0110 1000 xxxx xxxx xxxx 0111 xxxx */ - /* SXTAB cccc 0110 1010 xxxx xxxx xxxx 0111 xxxx */ - /* SXTAH cccc 0110 1011 xxxx xxxx xxxx 0111 xxxx */ - /* UXTAB16 cccc 0110 1100 xxxx xxxx xxxx 0111 xxxx */ - /* UXTAB cccc 0110 1110 xxxx xxxx xxxx 0111 xxxx */ - /* UXTAH cccc 0110 1111 xxxx xxxx xxxx 0111 xxxx */ - DECODE_EMULATEX (0x0f8000f0, 0x06800070, emulate_rd12rn16rm0_rwflags_nopc, - REGS(NOPCX, NOPC, 0, 0, NOPC)), - - DECODE_END -}; - -static const union decode_item arm_cccc_0111_____xxx1_table[] = { - /* Media instructions */ - - /* UNDEFINED cccc 0111 1111 xxxx xxxx xxxx 1111 xxxx */ - DECODE_REJECT (0x0ff000f0, 0x07f000f0), - - /* SMLALD cccc 0111 0100 xxxx xxxx xxxx 00x1 xxxx */ - /* SMLSLD cccc 0111 0100 xxxx xxxx xxxx 01x1 xxxx */ - DECODE_EMULATEX (0x0ff00090, 0x07400010, emulate_rdlo12rdhi16rn0rm8_rwflags_nopc, - REGS(NOPC, NOPC, NOPC, 0, NOPC)), - - /* SMUAD cccc 0111 0000 xxxx 1111 xxxx 00x1 xxxx */ - /* SMUSD cccc 0111 0000 xxxx 1111 xxxx 01x1 xxxx */ - DECODE_OR (0x0ff0f090, 0x0700f010), - /* SMMUL cccc 0111 0101 xxxx 1111 xxxx 00x1 xxxx */ - DECODE_OR (0x0ff0f0d0, 0x0750f010), - /* USAD8 cccc 0111 1000 xxxx 1111 xxxx 0001 xxxx */ - DECODE_EMULATEX (0x0ff0f0f0, 0x0780f010, emulate_rd16rn12rm0rs8_rwflags_nopc, - REGS(NOPC, 0, NOPC, 0, NOPC)), - - /* SMLAD cccc 0111 0000 xxxx xxxx xxxx 00x1 xxxx */ - /* SMLSD cccc 0111 0000 xxxx xxxx xxxx 01x1 xxxx */ - DECODE_OR (0x0ff00090, 0x07000010), - /* SMMLA cccc 0111 0101 xxxx xxxx xxxx 00x1 xxxx */ - DECODE_OR (0x0ff000d0, 0x07500010), - /* USADA8 cccc 0111 1000 xxxx xxxx xxxx 0001 xxxx */ - DECODE_EMULATEX (0x0ff000f0, 0x07800010, emulate_rd16rn12rm0rs8_rwflags_nopc, - REGS(NOPC, NOPCX, NOPC, 0, NOPC)), - - /* SMMLS cccc 0111 0101 xxxx xxxx xxxx 11x1 xxxx */ - DECODE_EMULATEX (0x0ff000d0, 0x075000d0, emulate_rd16rn12rm0rs8_rwflags_nopc, - REGS(NOPC, NOPC, NOPC, 0, NOPC)), - - /* SBFX cccc 0111 101x xxxx xxxx xxxx x101 xxxx */ - /* UBFX cccc 0111 111x xxxx xxxx xxxx x101 xxxx */ - DECODE_EMULATEX (0x0fa00070, 0x07a00050, emulate_rd12rm0_noflags_nopc, - REGS(0, NOPC, 0, 0, NOPC)), - - /* BFC cccc 0111 110x xxxx xxxx xxxx x001 1111 */ - DECODE_EMULATEX (0x0fe0007f, 0x07c0001f, emulate_rd12rm0_noflags_nopc, - REGS(0, NOPC, 0, 0, 0)), - - /* BFI cccc 0111 110x xxxx xxxx xxxx x001 xxxx */ - DECODE_EMULATEX (0x0fe00070, 0x07c00010, emulate_rd12rm0_noflags_nopc, - REGS(0, NOPC, 0, 0, NOPCX)), - - DECODE_END -}; - -static const union decode_item arm_cccc_01xx_table[] = { - /* Load/store word and unsigned byte */ - - /* LDRB/STRB pc,[...] cccc 01xx x0xx xxxx xxxx xxxx xxxx xxxx */ - DECODE_REJECT (0x0c40f000, 0x0440f000), - - /* STRT cccc 01x0 x010 xxxx xxxx xxxx xxxx xxxx */ - /* LDRT cccc 01x0 x011 xxxx xxxx xxxx xxxx xxxx */ - /* STRBT cccc 01x0 x110 xxxx xxxx xxxx xxxx xxxx */ - /* LDRBT cccc 01x0 x111 xxxx xxxx xxxx xxxx xxxx */ - DECODE_REJECT (0x0d200000, 0x04200000), - - /* STR (immediate) cccc 010x x0x0 xxxx xxxx xxxx xxxx xxxx */ - /* STRB (immediate) cccc 010x x1x0 xxxx xxxx xxxx xxxx xxxx */ - DECODE_EMULATEX (0x0e100000, 0x04000000, emulate_str, - REGS(NOPCWB, ANY, 0, 0, 0)), - - /* LDR (immediate) cccc 010x x0x1 xxxx xxxx xxxx xxxx xxxx */ - /* LDRB (immediate) cccc 010x x1x1 xxxx xxxx xxxx xxxx xxxx */ - DECODE_EMULATEX (0x0e100000, 0x04100000, emulate_ldr, - REGS(NOPCWB, ANY, 0, 0, 0)), - - /* STR (register) cccc 011x x0x0 xxxx xxxx xxxx xxxx xxxx */ - /* STRB (register) cccc 011x x1x0 xxxx xxxx xxxx xxxx xxxx */ - DECODE_EMULATEX (0x0e100000, 0x06000000, emulate_str, - REGS(NOPCWB, ANY, 0, 0, NOPC)), - - /* LDR (register) cccc 011x x0x1 xxxx xxxx xxxx xxxx xxxx */ - /* LDRB (register) cccc 011x x1x1 xxxx xxxx xxxx xxxx xxxx */ - DECODE_EMULATEX (0x0e100000, 0x06100000, emulate_ldr, - REGS(NOPCWB, ANY, 0, 0, NOPC)), - - DECODE_END -}; - -static const union decode_item arm_cccc_100x_table[] = { - /* Block data transfer instructions */ - - /* LDM cccc 100x x0x1 xxxx xxxx xxxx xxxx xxxx */ - /* STM cccc 100x x0x0 xxxx xxxx xxxx xxxx xxxx */ - DECODE_CUSTOM (0x0e400000, 0x08000000, kprobe_decode_ldmstm), - - /* STM (user registers) cccc 100x x1x0 xxxx xxxx xxxx xxxx xxxx */ - /* LDM (user registers) cccc 100x x1x1 xxxx 0xxx xxxx xxxx xxxx */ - /* LDM (exception ret) cccc 100x x1x1 xxxx 1xxx xxxx xxxx xxxx */ - DECODE_END -}; - -const union decode_item kprobe_decode_arm_table[] = { - /* - * Unconditional instructions - * 1111 xxxx xxxx xxxx xxxx xxxx xxxx xxxx - */ - DECODE_TABLE (0xf0000000, 0xf0000000, arm_1111_table), - - /* - * Miscellaneous instructions - * cccc 0001 0xx0 xxxx xxxx xxxx 0xxx xxxx - */ - DECODE_TABLE (0x0f900080, 0x01000000, arm_cccc_0001_0xx0____0xxx_table), - - /* - * Halfword multiply and multiply-accumulate - * cccc 0001 0xx0 xxxx xxxx xxxx 1xx0 xxxx - */ - DECODE_TABLE (0x0f900090, 0x01000080, arm_cccc_0001_0xx0____1xx0_table), - - /* - * Multiply and multiply-accumulate - * cccc 0000 xxxx xxxx xxxx xxxx 1001 xxxx - */ - DECODE_TABLE (0x0f0000f0, 0x00000090, arm_cccc_0000_____1001_table), - - /* - * Synchronization primitives - * cccc 0001 xxxx xxxx xxxx xxxx 1001 xxxx - */ - DECODE_TABLE (0x0f0000f0, 0x01000090, arm_cccc_0001_____1001_table), - - /* - * Extra load/store instructions - * cccc 000x xxxx xxxx xxxx xxxx 1xx1 xxxx - */ - DECODE_TABLE (0x0e000090, 0x00000090, arm_cccc_000x_____1xx1_table), - - /* - * Data-processing (register) - * cccc 000x xxxx xxxx xxxx xxxx xxx0 xxxx - * Data-processing (register-shifted register) - * cccc 000x xxxx xxxx xxxx xxxx 0xx1 xxxx - */ - DECODE_TABLE (0x0e000000, 0x00000000, arm_cccc_000x_table), - - /* - * Data-processing (immediate) - * cccc 001x xxxx xxxx xxxx xxxx xxxx xxxx - */ - DECODE_TABLE (0x0e000000, 0x02000000, arm_cccc_001x_table), - - /* - * Media instructions - * cccc 011x xxxx xxxx xxxx xxxx xxx1 xxxx - */ - DECODE_TABLE (0x0f000010, 0x06000010, arm_cccc_0110_____xxx1_table), - DECODE_TABLE (0x0f000010, 0x07000010, arm_cccc_0111_____xxx1_table), - - /* - * Load/store word and unsigned byte - * cccc 01xx xxxx xxxx xxxx xxxx xxxx xxxx - */ - DECODE_TABLE (0x0c000000, 0x04000000, arm_cccc_01xx_table), - - /* - * Block data transfer instructions - * cccc 100x xxxx xxxx xxxx xxxx xxxx xxxx - */ - DECODE_TABLE (0x0e000000, 0x08000000, arm_cccc_100x_table), - - /* B cccc 1010 xxxx xxxx xxxx xxxx xxxx xxxx */ - /* BL cccc 1011 xxxx xxxx xxxx xxxx xxxx xxxx */ - DECODE_SIMULATE (0x0e000000, 0x0a000000, simulate_bbl), - - /* - * Supervisor Call, and coprocessor instructions - */ - - /* MCRR cccc 1100 0100 xxxx xxxx xxxx xxxx xxxx */ - /* MRRC cccc 1100 0101 xxxx xxxx xxxx xxxx xxxx */ - /* LDC cccc 110x xxx1 xxxx xxxx xxxx xxxx xxxx */ - /* STC cccc 110x xxx0 xxxx xxxx xxxx xxxx xxxx */ - /* CDP cccc 1110 xxxx xxxx xxxx xxxx xxx0 xxxx */ - /* MCR cccc 1110 xxx0 xxxx xxxx xxxx xxx1 xxxx */ - /* MRC cccc 1110 xxx1 xxxx xxxx xxxx xxx1 xxxx */ - /* SVC cccc 1111 xxxx xxxx xxxx xxxx xxxx xxxx */ - DECODE_REJECT (0x0c000000, 0x0c000000), - - DECODE_END -}; -#ifdef CONFIG_ARM_KPROBES_TEST_MODULE -EXPORT_SYMBOL_GPL(kprobe_decode_arm_table); -#endif - -static void __kprobes arm_singlestep(struct kprobe *p, struct pt_regs *regs) -{ - regs->ARM_pc += 4; - p->ainsn.insn_handler(p, regs); -} - -/* Return: - * INSN_REJECTED If instruction is one not allowed to kprobe, - * INSN_GOOD If instruction is supported and uses instruction slot, - * INSN_GOOD_NO_SLOT If instruction is supported but doesn't use its slot. - * - * For instructions we don't want to kprobe (INSN_REJECTED return result): - * These are generally ones that modify the processor state making - * them "hard" to simulate such as switches processor modes or - * make accesses in alternate modes. Any of these could be simulated - * if the work was put into it, but low return considering they - * should also be very rare. - */ -enum kprobe_insn __kprobes -arm_kprobe_decode_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi) -{ - asi->insn_singlestep = arm_singlestep; - asi->insn_check_cc = kprobe_condition_checks[insn>>28]; - return kprobe_decode_insn(insn, asi, kprobe_decode_arm_table, false); -} diff --git a/arch/arm/kernel/kprobes-common.c b/arch/arm/kernel/kprobes-common.c index 455c8003bffb..f02c038059c3 100644 --- a/arch/arm/kernel/kprobes-common.c +++ b/arch/arm/kernel/kprobes-common.c @@ -13,178 +13,10 @@ #include <linux/kernel.h> #include <linux/kprobes.h> -#include <asm/system_info.h> -#include <linux/types.h> -#include <linux/stddef.h> -#include <linux/bug.h> #include "kprobes.h" -#ifndef find_str_pc_offset - -/* - * For STR and STM instructions, an ARM core may choose to use either - * a +8 or a +12 displacement from the current instruction's address. - * Whichever value is chosen for a given core, it must be the same for - * both instructions and may not change. This function measures it. - */ - -int str_pc_offset; - -void __init find_str_pc_offset(void) -{ - int addr, scratch, ret; - - __asm__ ( - "sub %[ret], pc, #4 \n\t" - "str pc, %[addr] \n\t" - "ldr %[scr], %[addr] \n\t" - "sub %[ret], %[scr], %[ret] \n\t" - : [ret] "=r" (ret), [scr] "=r" (scratch), [addr] "+m" (addr)); - - str_pc_offset = ret; -} - -#endif /* !find_str_pc_offset */ - - -#ifndef test_load_write_pc_interworking - -bool load_write_pc_interworks; - -void __init test_load_write_pc_interworking(void) -{ - int arch = cpu_architecture(); - BUG_ON(arch == CPU_ARCH_UNKNOWN); - load_write_pc_interworks = arch >= CPU_ARCH_ARMv5T; -} - -#endif /* !test_load_write_pc_interworking */ - - -#ifndef test_alu_write_pc_interworking - -bool alu_write_pc_interworks; - -void __init test_alu_write_pc_interworking(void) -{ - int arch = cpu_architecture(); - BUG_ON(arch == CPU_ARCH_UNKNOWN); - alu_write_pc_interworks = arch >= CPU_ARCH_ARMv7; -} - -#endif /* !test_alu_write_pc_interworking */ - - -void __init arm_kprobe_decode_init(void) -{ - find_str_pc_offset(); - test_load_write_pc_interworking(); - test_alu_write_pc_interworking(); -} - - -static unsigned long __kprobes __check_eq(unsigned long cpsr) -{ - return cpsr & PSR_Z_BIT; -} - -static unsigned long __kprobes __check_ne(unsigned long cpsr) -{ - return (~cpsr) & PSR_Z_BIT; -} - -static unsigned long __kprobes __check_cs(unsigned long cpsr) -{ - return cpsr & PSR_C_BIT; -} - -static unsigned long __kprobes __check_cc(unsigned long cpsr) -{ - return (~cpsr) & PSR_C_BIT; -} - -static unsigned long __kprobes __check_mi(unsigned long cpsr) -{ - return cpsr & PSR_N_BIT; -} - -static unsigned long __kprobes __check_pl(unsigned long cpsr) -{ - return (~cpsr) & PSR_N_BIT; -} - -static unsigned long __kprobes __check_vs(unsigned long cpsr) -{ - return cpsr & PSR_V_BIT; -} - -static unsigned long __kprobes __check_vc(unsigned long cpsr) -{ - return (~cpsr) & PSR_V_BIT; -} - -static unsigned long __kprobes __check_hi(unsigned long cpsr) -{ - cpsr &= ~(cpsr >> 1); /* PSR_C_BIT &= ~PSR_Z_BIT */ - return cpsr & PSR_C_BIT; -} - -static unsigned long __kprobes __check_ls(unsigned long cpsr) -{ - cpsr &= ~(cpsr >> 1); /* PSR_C_BIT &= ~PSR_Z_BIT */ - return (~cpsr) & PSR_C_BIT; -} - -static unsigned long __kprobes __check_ge(unsigned long cpsr) -{ - cpsr ^= (cpsr << 3); /* PSR_N_BIT ^= PSR_V_BIT */ - return (~cpsr) & PSR_N_BIT; -} - -static unsigned long __kprobes __check_lt(unsigned long cpsr) -{ - cpsr ^= (cpsr << 3); /* PSR_N_BIT ^= PSR_V_BIT */ - return cpsr & PSR_N_BIT; -} - -static unsigned long __kprobes __check_gt(unsigned long cpsr) -{ - unsigned long temp = cpsr ^ (cpsr << 3); /* PSR_N_BIT ^= PSR_V_BIT */ - temp |= (cpsr << 1); /* PSR_N_BIT |= PSR_Z_BIT */ - return (~temp) & PSR_N_BIT; -} - -static unsigned long __kprobes __check_le(unsigned long cpsr) -{ - unsigned long temp = cpsr ^ (cpsr << 3); /* PSR_N_BIT ^= PSR_V_BIT */ - temp |= (cpsr << 1); /* PSR_N_BIT |= PSR_Z_BIT */ - return temp & PSR_N_BIT; -} - -static unsigned long __kprobes __check_al(unsigned long cpsr) -{ - return true; -} - -kprobe_check_cc * const kprobe_condition_checks[16] = { - &__check_eq, &__check_ne, &__check_cs, &__check_cc, - &__check_mi, &__check_pl, &__check_vs, &__check_vc, - &__check_hi, &__check_ls, &__check_ge, &__check_lt, - &__check_gt, &__check_le, &__check_al, &__check_al -}; - - -void __kprobes kprobe_simulate_nop(struct kprobe *p, struct pt_regs *regs) -{ -} - -void __kprobes kprobe_emulate_none(struct kprobe *p, struct pt_regs *regs) -{ - p->ainsn.insn_fn(); -} - static void __kprobes simulate_ldm1stm1(struct kprobe *p, struct pt_regs *regs) { kprobe_opcode_t insn = p->opcode; @@ -322,260 +154,3 @@ kprobe_decode_ldmstm(kprobe_opcode_t insn, struct arch_specific_insn *asi) return INSN_GOOD_NO_SLOT; } - -/* - * Prepare an instruction slot to receive an instruction for emulating. - * This is done by placing a subroutine return after the location where the - * instruction will be placed. We also modify ARM instructions to be - * unconditional as the condition code will already be checked before any - * emulation handler is called. - */ -static kprobe_opcode_t __kprobes -prepare_emulated_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi, - bool thumb) -{ -#ifdef CONFIG_THUMB2_KERNEL - if (thumb) { - u16 *thumb_insn = (u16 *)asi->insn; - thumb_insn[1] = 0x4770; /* Thumb bx lr */ - thumb_insn[2] = 0x4770; /* Thumb bx lr */ - return insn; - } - asi->insn[1] = 0xe12fff1e; /* ARM bx lr */ -#else - asi->insn[1] = 0xe1a0f00e; /* mov pc, lr */ -#endif - /* Make an ARM instruction unconditional */ - if (insn < 0xe0000000) - insn = (insn | 0xe0000000) & ~0x10000000; - return insn; -} - -/* - * Write a (probably modified) instruction into the slot previously prepared by - * prepare_emulated_insn - */ -static void __kprobes -set_emulated_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi, - bool thumb) -{ -#ifdef CONFIG_THUMB2_KERNEL - if (thumb) { - u16 *ip = (u16 *)asi->insn; - if (is_wide_instruction(insn)) - *ip++ = insn >> 16; - *ip++ = insn; - return; - } -#endif - asi->insn[0] = insn; -} - -/* - * When we modify the register numbers encoded in an instruction to be emulated, - * the new values come from this define. For ARM and 32-bit Thumb instructions - * this gives... - * - * bit position 16 12 8 4 0 - * ---------------+---+---+---+---+---+ - * register r2 r0 r1 -- r3 - */ -#define INSN_NEW_BITS 0x00020103 - -/* Each nibble has same value as that at INSN_NEW_BITS bit 16 */ -#define INSN_SAMEAS16_BITS 0x22222222 - -/* - * Validate and modify each of the registers encoded in an instruction. - * - * Each nibble in regs contains a value from enum decode_reg_type. For each - * non-zero value, the corresponding nibble in pinsn is validated and modified - * according to the type. - */ -static bool __kprobes decode_regs(kprobe_opcode_t* pinsn, u32 regs) -{ - kprobe_opcode_t insn = *pinsn; - kprobe_opcode_t mask = 0xf; /* Start at least significant nibble */ - - for (; regs != 0; regs >>= 4, mask <<= 4) { - - kprobe_opcode_t new_bits = INSN_NEW_BITS; - - switch (regs & 0xf) { - - case REG_TYPE_NONE: - /* Nibble not a register, skip to next */ - continue; - - case REG_TYPE_ANY: - /* Any register is allowed */ - break; - - case REG_TYPE_SAMEAS16: - /* Replace register with same as at bit position 16 */ - new_bits = INSN_SAMEAS16_BITS; - break; - - case REG_TYPE_SP: - /* Only allow SP (R13) */ - if ((insn ^ 0xdddddddd) & mask) - goto reject; - break; - - case REG_TYPE_PC: - /* Only allow PC (R15) */ - if ((insn ^ 0xffffffff) & mask) - goto reject; - break; - - case REG_TYPE_NOSP: - /* Reject SP (R13) */ - if (((insn ^ 0xdddddddd) & mask) == 0) - goto reject; - break; - - case REG_TYPE_NOSPPC: - case REG_TYPE_NOSPPCX: - /* Reject SP and PC (R13 and R15) */ - if (((insn ^ 0xdddddddd) & 0xdddddddd & mask) == 0) - goto reject; - break; - - case REG_TYPE_NOPCWB: - if (!is_writeback(insn)) - break; /* No writeback, so any register is OK */ - /* fall through... */ - case REG_TYPE_NOPC: - case REG_TYPE_NOPCX: - /* Reject PC (R15) */ - if (((insn ^ 0xffffffff) & mask) == 0) - goto reject; - break; - } - - /* Replace value of nibble with new register number... */ - insn &= ~mask; - insn |= new_bits & mask; - } - - *pinsn = insn; - return true; - -reject: - return false; -} - -static const int decode_struct_sizes[NUM_DECODE_TYPES] = { - [DECODE_TYPE_TABLE] = sizeof(struct decode_table), - [DECODE_TYPE_CUSTOM] = sizeof(struct decode_custom), - [DECODE_TYPE_SIMULATE] = sizeof(struct decode_simulate), - [DECODE_TYPE_EMULATE] = sizeof(struct decode_emulate), - [DECODE_TYPE_OR] = sizeof(struct decode_or), - [DECODE_TYPE_REJECT] = sizeof(struct decode_reject) -}; - -/* - * kprobe_decode_insn operates on data tables in order to decode an ARM - * architecture instruction onto which a kprobe has been placed. - * - * These instruction decoding tables are a concatenation of entries each - * of which consist of one of the following structs: - * - * decode_table - * decode_custom - * decode_simulate - * decode_emulate - * decode_or - * decode_reject - * - * Each of these starts with a struct decode_header which has the following - * fields: - * - * type_regs - * mask - * value - * - * The least significant DECODE_TYPE_BITS of type_regs contains a value - * from enum decode_type, this indicates which of the decode_* structs - * the entry contains. The value DECODE_TYPE_END indicates the end of the - * table. - * - * When the table is parsed, each entry is checked in turn to see if it - * matches the instruction to be decoded using the test: - * - * (insn & mask) == value - * - * If no match is found before the end of the table is reached then decoding - * fails with INSN_REJECTED. - * - * When a match is found, decode_regs() is called to validate and modify each - * of the registers encoded in the instruction; the data it uses to do this - * is (type_regs >> DECODE_TYPE_BITS). A validation failure will cause decoding - * to fail with INSN_REJECTED. - * - * Once the instruction has passed the above tests, further processing - * depends on the type of the table entry's decode struct. - * - */ -int __kprobes -kprobe_decode_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi, - const union decode_item *table, bool thumb) -{ - const struct decode_header *h = (struct decode_header *)table; - const struct decode_header *next; - bool matched = false; - - insn = prepare_emulated_insn(insn, asi, thumb); - - for (;; h = next) { - enum decode_type type = h->type_regs.bits & DECODE_TYPE_MASK; - u32 regs = h->type_regs.bits >> DECODE_TYPE_BITS; - - if (type == DECODE_TYPE_END) - return INSN_REJECTED; - - next = (struct decode_header *) - ((uintptr_t)h + decode_struct_sizes[type]); - - if (!matched && (insn & h->mask.bits) != h->value.bits) - continue; - - if (!decode_regs(&insn, regs)) - return INSN_REJECTED; - - switch (type) { - - case DECODE_TYPE_TABLE: { - struct decode_table *d = (struct decode_table *)h; - next = (struct decode_header *)d->table.table; - break; - } - - case DECODE_TYPE_CUSTOM: { - struct decode_custom *d = (struct decode_custom *)h; - return (*d->decoder.decoder)(insn, asi); - } - - case DECODE_TYPE_SIMULATE: { - struct decode_simulate *d = (struct decode_simulate *)h; - asi->insn_handler = d->handler.handler; - return INSN_GOOD_NO_SLOT; - } - - case DECODE_TYPE_EMULATE: { - struct decode_emulate *d = (struct decode_emulate *)h; - asi->insn_handler = d->handler.handler; - set_emulated_insn(insn, asi, thumb); - return INSN_GOOD; - } - - case DECODE_TYPE_OR: - matched = true; - break; - - case DECODE_TYPE_REJECT: - default: - return INSN_REJECTED; - } - } - } diff --git a/arch/arm/kernel/kprobes.h b/arch/arm/kernel/kprobes.h index 38945f78f9f1..aa68c0ea1a0b 100644 --- a/arch/arm/kernel/kprobes.h +++ b/arch/arm/kernel/kprobes.h @@ -52,377 +52,6 @@ enum kprobe_insn arm_kprobe_decode_insn(kprobe_opcode_t, void __init arm_kprobe_decode_init(void); -extern kprobe_check_cc * const kprobe_condition_checks[16]; - - -#if __LINUX_ARM_ARCH__ >= 7 - -/* str_pc_offset is architecturally defined from ARMv7 onwards */ -#define str_pc_offset 8 -#define find_str_pc_offset() - -#else /* __LINUX_ARM_ARCH__ < 7 */ - -/* We need a run-time check to determine str_pc_offset */ -extern int str_pc_offset; -void __init find_str_pc_offset(void); - -#endif - - -/* - * Update ITSTATE after normal execution of an IT block instruction. - * - * The 8 IT state bits are split into two parts in CPSR: - * ITSTATE<1:0> are in CPSR<26:25> - * ITSTATE<7:2> are in CPSR<15:10> - */ -static inline unsigned long it_advance(unsigned long cpsr) - { - if ((cpsr & 0x06000400) == 0) { - /* ITSTATE<2:0> == 0 means end of IT block, so clear IT state */ - cpsr &= ~PSR_IT_MASK; - } else { - /* We need to shift left ITSTATE<4:0> */ - const unsigned long mask = 0x06001c00; /* Mask ITSTATE<4:0> */ - unsigned long it = cpsr & mask; - it <<= 1; - it |= it >> (27 - 10); /* Carry ITSTATE<2> to correct place */ - it &= mask; - cpsr &= ~mask; - cpsr |= it; - } - return cpsr; -} - -static inline void __kprobes bx_write_pc(long pcv, struct pt_regs *regs) -{ - long cpsr = regs->ARM_cpsr; - if (pcv & 0x1) { - cpsr |= PSR_T_BIT; - pcv &= ~0x1; - } else { - cpsr &= ~PSR_T_BIT; - pcv &= ~0x2; /* Avoid UNPREDICTABLE address allignment */ - } - regs->ARM_cpsr = cpsr; - regs->ARM_pc = pcv; -} - - -#if __LINUX_ARM_ARCH__ >= 6 - -/* Kernels built for >= ARMv6 should never run on <= ARMv5 hardware, so... */ -#define load_write_pc_interworks true -#define test_load_write_pc_interworking() - -#else /* __LINUX_ARM_ARCH__ < 6 */ - -/* We need run-time testing to determine if load_write_pc() should interwork. */ -extern bool load_write_pc_interworks; -void __init test_load_write_pc_interworking(void); - -#endif - -static inline void __kprobes load_write_pc(long pcv, struct pt_regs *regs) -{ - if (load_write_pc_interworks) - bx_write_pc(pcv, regs); - else - regs->ARM_pc = pcv; -} - - -#if __LINUX_ARM_ARCH__ >= 7 - -#define alu_write_pc_interworks true -#define test_alu_write_pc_interworking() - -#elif __LINUX_ARM_ARCH__ <= 5 - -/* Kernels built for <= ARMv5 should never run on >= ARMv6 hardware, so... */ -#define alu_write_pc_interworks false -#define test_alu_write_pc_interworking() - -#else /* __LINUX_ARM_ARCH__ == 6 */ - -/* We could be an ARMv6 binary on ARMv7 hardware so we need a run-time check. */ -extern bool alu_write_pc_interworks; -void __init test_alu_write_pc_interworking(void); - -#endif /* __LINUX_ARM_ARCH__ == 6 */ - -static inline void __kprobes alu_write_pc(long pcv, struct pt_regs *regs) -{ - if (alu_write_pc_interworks) - bx_write_pc(pcv, regs); - else - regs->ARM_pc = pcv; -} - - -void __kprobes kprobe_simulate_nop(struct kprobe *p, struct pt_regs *regs); -void __kprobes kprobe_emulate_none(struct kprobe *p, struct pt_regs *regs); - -enum kprobe_insn __kprobes -kprobe_decode_ldmstm(kprobe_opcode_t insn, struct arch_specific_insn *asi); - -/* - * Test if load/store instructions writeback the address register. - * if P (bit 24) == 0 or W (bit 21) == 1 - */ -#define is_writeback(insn) ((insn ^ 0x01000000) & 0x01200000) - -/* - * The following definitions and macros are used to build instruction - * decoding tables for use by kprobe_decode_insn. - * - * These tables are a concatenation of entries each of which consist of one of - * the decode_* structs. All of the fields in every type of decode structure - * are of the union type decode_item, therefore the entire decode table can be - * viewed as an array of these and declared like: - * - * static const union decode_item table_name[] = {}; - * - * In order to construct each entry in the table, macros are used to - * initialise a number of sequential decode_item values in a layout which - * matches the relevant struct. E.g. DECODE_SIMULATE initialise a struct - * decode_simulate by initialising four decode_item objects like this... - * - * {.bits = _type}, - * {.bits = _mask}, - * {.bits = _value}, - * {.handler = _handler}, - * - * Initialising a specified member of the union means that the compiler - * will produce a warning if the argument is of an incorrect type. - * - * Below is a list of each of the macros used to initialise entries and a - * description of the action performed when that entry is matched to an - * instruction. A match is found when (instruction & mask) == value. - * - * DECODE_TABLE(mask, value, table) - * Instruction decoding jumps to parsing the new sub-table 'table'. - * - * DECODE_CUSTOM(mask, value, decoder) - * The custom function 'decoder' is called to the complete decoding - * of an instruction. - * - * DECODE_SIMULATE(mask, value, handler) - * Set the probes instruction handler to 'handler', this will be used - * to simulate the instruction when the probe is hit. Decoding returns - * with INSN_GOOD_NO_SLOT. - * - * DECODE_EMULATE(mask, value, handler) - * Set the probes instruction handler to 'handler', this will be used - * to emulate the instruction when the probe is hit. The modified - * instruction (see below) is placed in the probes instruction slot so it - * may be called by the emulation code. Decoding returns with INSN_GOOD. - * - * DECODE_REJECT(mask, value) - * Instruction decoding fails with INSN_REJECTED - * - * DECODE_OR(mask, value) - * This allows the mask/value test of multiple table entries to be - * logically ORed. Once an 'or' entry is matched the decoding action to - * be performed is that of the next entry which isn't an 'or'. E.g. - * - * DECODE_OR (mask1, value1) - * DECODE_OR (mask2, value2) - * DECODE_SIMULATE (mask3, value3, simulation_handler) - * - * This means that if any of the three mask/value pairs match the - * instruction being decoded, then 'simulation_handler' will be used - * for it. - * - * Both the SIMULATE and EMULATE macros have a second form which take an - * additional 'regs' argument. - * - * DECODE_SIMULATEX(mask, value, handler, regs) - * DECODE_EMULATEX (mask, value, handler, regs) - * - * These are used to specify what kind of CPU register is encoded in each of the - * least significant 5 nibbles of the instruction being decoded. The regs value - * is specified using the REGS macro, this takes any of the REG_TYPE_* values - * from enum decode_reg_type as arguments; only the '*' part of the name is - * given. E.g. - * - * REGS(0, ANY, NOPC, 0, ANY) - * - * This indicates an instruction is encoded like: - * - * bits 19..16 ignore - * bits 15..12 any register allowed here - * bits 11.. 8 any register except PC allowed here - * bits 7.. 4 ignore - * bits 3.. 0 any register allowed here - * - * This register specification is checked after a decode table entry is found to - * match an instruction (through the mask/value test). Any invalid register then - * found in the instruction will cause decoding to fail with INSN_REJECTED. In - * the above example this would happen if bits 11..8 of the instruction were - * 1111, indicating R15 or PC. - * - * As well as checking for legal combinations of registers, this data is also - * used to modify the registers encoded in the instructions so that an - * emulation routines can use it. (See decode_regs() and INSN_NEW_BITS.) - * - * Here is a real example which matches ARM instructions of the form - * "AND <Rd>,<Rn>,<Rm>,<shift> <Rs>" - * - * DECODE_EMULATEX (0x0e000090, 0x00000010, emulate_rd12rn16rm0rs8_rwflags, - * REGS(ANY, ANY, NOPC, 0, ANY)), - * ^ ^ ^ ^ - * Rn Rd Rs Rm - * - * Decoding the instruction "AND R4, R5, R6, ASL R15" will be rejected because - * Rs == R15 - * - * Decoding the instruction "AND R4, R5, R6, ASL R7" will be accepted and the - * instruction will be modified to "AND R0, R2, R3, ASL R1" and then placed into - * the kprobes instruction slot. This can then be called later by the handler - * function emulate_rd12rn16rm0rs8_rwflags in order to simulate the instruction. - */ - -enum decode_type { - DECODE_TYPE_END, - DECODE_TYPE_TABLE, - DECODE_TYPE_CUSTOM, - DECODE_TYPE_SIMULATE, - DECODE_TYPE_EMULATE, - DECODE_TYPE_OR, - DECODE_TYPE_REJECT, - NUM_DECODE_TYPES /* Must be last enum */ -}; - -#define DECODE_TYPE_BITS 4 -#define DECODE_TYPE_MASK ((1 << DECODE_TYPE_BITS) - 1) - -enum decode_reg_type { - REG_TYPE_NONE = 0, /* Not a register, ignore */ - REG_TYPE_ANY, /* Any register allowed */ - REG_TYPE_SAMEAS16, /* Register should be same as that at bits 19..16 */ - REG_TYPE_SP, /* Register must be SP */ - REG_TYPE_PC, /* Register must be PC */ - REG_TYPE_NOSP, /* Register must not be SP */ - REG_TYPE_NOSPPC, /* Register must not be SP or PC */ - REG_TYPE_NOPC, /* Register must not be PC */ - REG_TYPE_NOPCWB, /* No PC if load/store write-back flag also set */ - - /* The following types are used when the encoding for PC indicates - * another instruction form. This distiction only matters for test - * case coverage checks. - */ - REG_TYPE_NOPCX, /* Register must not be PC */ - REG_TYPE_NOSPPCX, /* Register must not be SP or PC */ - - /* Alias to allow '0' arg to be used in REGS macro. */ - REG_TYPE_0 = REG_TYPE_NONE -}; - -#define REGS(r16, r12, r8, r4, r0) \ - ((REG_TYPE_##r16) << 16) + \ - ((REG_TYPE_##r12) << 12) + \ - ((REG_TYPE_##r8) << 8) + \ - ((REG_TYPE_##r4) << 4) + \ - (REG_TYPE_##r0) - -union decode_item { - u32 bits; - const union decode_item *table; - kprobe_insn_handler_t *handler; - kprobe_decode_insn_t *decoder; -}; - - -#define DECODE_END \ - {.bits = DECODE_TYPE_END} - - -struct decode_header { - union decode_item type_regs; - union decode_item mask; - union decode_item value; -}; - -#define DECODE_HEADER(_type, _mask, _value, _regs) \ - {.bits = (_type) | ((_regs) << DECODE_TYPE_BITS)}, \ - {.bits = (_mask)}, \ - {.bits = (_value)} - - -struct decode_table { - struct decode_header header; - union decode_item table; -}; - -#define DECODE_TABLE(_mask, _value, _table) \ - DECODE_HEADER(DECODE_TYPE_TABLE, _mask, _value, 0), \ - {.table = (_table)} - - -struct decode_custom { - struct decode_header header; - union decode_item decoder; -}; - -#define DECODE_CUSTOM(_mask, _value, _decoder) \ - DECODE_HEADER(DECODE_TYPE_CUSTOM, _mask, _value, 0), \ - {.decoder = (_decoder)} - - -struct decode_simulate { - struct decode_header header; - union decode_item handler; -}; - -#define DECODE_SIMULATEX(_mask, _value, _handler, _regs) \ - DECODE_HEADER(DECODE_TYPE_SIMULATE, _mask, _value, _regs), \ - {.handler = (_handler)} - -#define DECODE_SIMULATE(_mask, _value, _handler) \ - DECODE_SIMULATEX(_mask, _value, _handler, 0) - - -struct decode_emulate { - struct decode_header header; - union decode_item handler; -}; - -#define DECODE_EMULATEX(_mask, _value, _handler, _regs) \ - DECODE_HEADER(DECODE_TYPE_EMULATE, _mask, _value, _regs), \ - {.handler = (_handler)} - -#define DECODE_EMULATE(_mask, _value, _handler) \ - DECODE_EMULATEX(_mask, _value, _handler, 0) - - -struct decode_or { - struct decode_header header; -}; - -#define DECODE_OR(_mask, _value) \ - DECODE_HEADER(DECODE_TYPE_OR, _mask, _value, 0) - - -struct decode_reject { - struct decode_header header; -}; - -#define DECODE_REJECT(_mask, _value) \ - DECODE_HEADER(DECODE_TYPE_REJECT, _mask, _value, 0) - - -#ifdef CONFIG_THUMB2_KERNEL -extern const union decode_item kprobe_decode_thumb16_table[]; -extern const union decode_item kprobe_decode_thumb32_table[]; -#else -extern const union decode_item kprobe_decode_arm_table[]; -#endif - - -int kprobe_decode_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi, - const union decode_item *table, bool thumb16); - +#include "probes.h" #endif /* _ARM_KERNEL_KPROBES_H */ diff --git a/arch/arm/kernel/probes-arm.c b/arch/arm/kernel/probes-arm.c new file mode 100644 index 000000000000..57e08b28e87f --- /dev/null +++ b/arch/arm/kernel/probes-arm.c @@ -0,0 +1,731 @@ +/* + * arch/arm/kernel/probes-arm.c + * + * Some code moved here from arch/arm/kernel/kprobes-arm.c + * + * Copyright (C) 2006, 2007 Motorola Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/stddef.h> +#include <linux/ptrace.h> +#include <linux/kprobes.h> + +#include "kprobes.h" +#include "probes-arm.h" + +#define sign_extend(x, signbit) ((x) | (0 - ((x) & (1 << (signbit))))) + +#define branch_displacement(insn) sign_extend(((insn) & 0xffffff) << 2, 25) + +/* + * To avoid the complications of mimicing single-stepping on a + * processor without a Next-PC or a single-step mode, and to + * avoid having to deal with the side-effects of boosting, we + * simulate or emulate (almost) all ARM instructions. + * + * "Simulation" is where the instruction's behavior is duplicated in + * C code. "Emulation" is where the original instruction is rewritten + * and executed, often by altering its registers. + * + * By having all behavior of the kprobe'd instruction completed before + * returning from the kprobe_handler(), all locks (scheduler and + * interrupt) can safely be released. There is no need for secondary + * breakpoints, no race with MP or preemptable kernels, nor having to + * clean up resources counts at a later time impacting overall system + * performance. By rewriting the instruction, only the minimum registers + * need to be loaded and saved back optimizing performance. + * + * Calling the insnslot_*_rwflags version of a function doesn't hurt + * anything even when the CPSR flags aren't updated by the + * instruction. It's just a little slower in return for saving + * a little space by not having a duplicate function that doesn't + * update the flags. (The same optimization can be said for + * instructions that do or don't perform register writeback) + * Also, instructions can either read the flags, only write the + * flags, or read and write the flags. To save combinations + * rather than for sheer performance, flag functions just assume + * read and write of flags. + */ + +void __kprobes simulate_bbl(struct kprobe *p, struct pt_regs *regs) +{ + kprobe_opcode_t insn = p->opcode; + long iaddr = (long)p->addr; + int disp = branch_displacement(insn); + + if (insn & (1 << 24)) + regs->ARM_lr = iaddr + 4; + + regs->ARM_pc = iaddr + 8 + disp; +} + +void __kprobes simulate_blx1(struct kprobe *p, struct pt_regs *regs) +{ + kprobe_opcode_t insn = p->opcode; + long iaddr = (long)p->addr; + int disp = branch_displacement(insn); + + regs->ARM_lr = iaddr + 4; + regs->ARM_pc = iaddr + 8 + disp + ((insn >> 23) & 0x2); + regs->ARM_cpsr |= PSR_T_BIT; +} + +void __kprobes simulate_blx2bx(struct kprobe *p, struct pt_regs *regs) +{ + kprobe_opcode_t insn = p->opcode; + int rm = insn & 0xf; + long rmv = regs->uregs[rm]; + + if (insn & (1 << 5)) + regs->ARM_lr = (long)p->addr + 4; + + regs->ARM_pc = rmv & ~0x1; + regs->ARM_cpsr &= ~PSR_T_BIT; + if (rmv & 0x1) + regs->ARM_cpsr |= PSR_T_BIT; +} + +void __kprobes simulate_mrs(struct kprobe *p, struct pt_regs *regs) +{ + kprobe_opcode_t insn = p->opcode; + int rd = (insn >> 12) & 0xf; + unsigned long mask = 0xf8ff03df; /* Mask out execution state */ + regs->uregs[rd] = regs->ARM_cpsr & mask; +} + +void __kprobes simulate_mov_ipsp(struct kprobe *p, struct pt_regs *regs) +{ + regs->uregs[12] = regs->uregs[13]; +} + +/* + * For the instruction masking and comparisons in all the "space_*" + * functions below, Do _not_ rearrange the order of tests unless + * you're very, very sure of what you are doing. For the sake of + * efficiency, the masks for some tests sometimes assume other test + * have been done prior to them so the number of patterns to test + * for an instruction set can be as broad as possible to reduce the + * number of tests needed. + */ + +static const union decode_item arm_1111_table[] = { + /* Unconditional instructions */ + + /* memory hint 1111 0100 x001 xxxx xxxx xxxx xxxx xxxx */ + /* PLDI (immediate) 1111 0100 x101 xxxx xxxx xxxx xxxx xxxx */ + /* PLDW (immediate) 1111 0101 x001 xxxx xxxx xxxx xxxx xxxx */ + /* PLD (immediate) 1111 0101 x101 xxxx xxxx xxxx xxxx xxxx */ + DECODE_SIMULATE (0xfe300000, 0xf4100000, kprobe_simulate_nop), + + /* memory hint 1111 0110 x001 xxxx xxxx xxxx xxx0 xxxx */ + /* PLDI (register) 1111 0110 x101 xxxx xxxx xxxx xxx0 xxxx */ + /* PLDW (register) 1111 0111 x001 xxxx xxxx xxxx xxx0 xxxx */ + /* PLD (register) 1111 0111 x101 xxxx xxxx xxxx xxx0 xxxx */ + DECODE_SIMULATE (0xfe300010, 0xf6100000, kprobe_simulate_nop), + + /* BLX (immediate) 1111 101x xxxx xxxx xxxx xxxx xxxx xxxx */ + DECODE_SIMULATE (0xfe000000, 0xfa000000, simulate_blx1), + + /* CPS 1111 0001 0000 xxx0 xxxx xxxx xx0x xxxx */ + /* SETEND 1111 0001 0000 0001 xxxx xxxx 0000 xxxx */ + /* SRS 1111 100x x1x0 xxxx xxxx xxxx xxxx xxxx */ + /* RFE 1111 100x x0x1 xxxx xxxx xxxx xxxx xxxx */ + + /* Coprocessor instructions... */ + /* MCRR2 1111 1100 0100 xxxx xxxx xxxx xxxx xxxx */ + /* MRRC2 1111 1100 0101 xxxx xxxx xxxx xxxx xxxx */ + /* LDC2 1111 110x xxx1 xxxx xxxx xxxx xxxx xxxx */ + /* STC2 1111 110x xxx0 xxxx xxxx xxxx xxxx xxxx */ + /* CDP2 1111 1110 xxxx xxxx xxxx xxxx xxx0 xxxx */ + /* MCR2 1111 1110 xxx0 xxxx xxxx xxxx xxx1 xxxx */ + /* MRC2 1111 1110 xxx1 xxxx xxxx xxxx xxx1 xxxx */ + + /* Other unallocated instructions... */ + DECODE_END +}; + +static const union decode_item arm_cccc_0001_0xx0____0xxx_table[] = { + /* Miscellaneous instructions */ + + /* MRS cpsr cccc 0001 0000 xxxx xxxx xxxx 0000 xxxx */ + DECODE_SIMULATEX(0x0ff000f0, 0x01000000, simulate_mrs, + REGS(0, NOPC, 0, 0, 0)), + + /* BX cccc 0001 0010 xxxx xxxx xxxx 0001 xxxx */ + DECODE_SIMULATE (0x0ff000f0, 0x01200010, simulate_blx2bx), + + /* BLX (register) cccc 0001 0010 xxxx xxxx xxxx 0011 xxxx */ + DECODE_SIMULATEX(0x0ff000f0, 0x01200030, simulate_blx2bx, + REGS(0, 0, 0, 0, NOPC)), + + /* CLZ cccc 0001 0110 xxxx xxxx xxxx 0001 xxxx */ + DECODE_EMULATEX (0x0ff000f0, 0x01600010, emulate_rd12rm0_noflags_nopc, + REGS(0, NOPC, 0, 0, NOPC)), + + /* QADD cccc 0001 0000 xxxx xxxx xxxx 0101 xxxx */ + /* QSUB cccc 0001 0010 xxxx xxxx xxxx 0101 xxxx */ + /* QDADD cccc 0001 0100 xxxx xxxx xxxx 0101 xxxx */ + /* QDSUB cccc 0001 0110 xxxx xxxx xxxx 0101 xxxx */ + DECODE_EMULATEX (0x0f9000f0, 0x01000050, emulate_rd12rn16rm0_rwflags_nopc, + REGS(NOPC, NOPC, 0, 0, NOPC)), + + /* BXJ cccc 0001 0010 xxxx xxxx xxxx 0010 xxxx */ + /* MSR cccc 0001 0x10 xxxx xxxx xxxx 0000 xxxx */ + /* MRS spsr cccc 0001 0100 xxxx xxxx xxxx 0000 xxxx */ + /* BKPT 1110 0001 0010 xxxx xxxx xxxx 0111 xxxx */ + /* SMC cccc 0001 0110 xxxx xxxx xxxx 0111 xxxx */ + /* And unallocated instructions... */ + DECODE_END +}; + +static const union decode_item arm_cccc_0001_0xx0____1xx0_table[] = { + /* Halfword multiply and multiply-accumulate */ + + /* SMLALxy cccc 0001 0100 xxxx xxxx xxxx 1xx0 xxxx */ + DECODE_EMULATEX (0x0ff00090, 0x01400080, emulate_rdlo12rdhi16rn0rm8_rwflags_nopc, + REGS(NOPC, NOPC, NOPC, 0, NOPC)), + + /* SMULWy cccc 0001 0010 xxxx xxxx xxxx 1x10 xxxx */ + DECODE_OR (0x0ff000b0, 0x012000a0), + /* SMULxy cccc 0001 0110 xxxx xxxx xxxx 1xx0 xxxx */ + DECODE_EMULATEX (0x0ff00090, 0x01600080, emulate_rd16rn12rm0rs8_rwflags_nopc, + REGS(NOPC, 0, NOPC, 0, NOPC)), + + /* SMLAxy cccc 0001 0000 xxxx xxxx xxxx 1xx0 xxxx */ + DECODE_OR (0x0ff00090, 0x01000080), + /* SMLAWy cccc 0001 0010 xxxx xxxx xxxx 1x00 xxxx */ + DECODE_EMULATEX (0x0ff000b0, 0x01200080, emulate_rd16rn12rm0rs8_rwflags_nopc, + REGS(NOPC, NOPC, NOPC, 0, NOPC)), + + DECODE_END +}; + +static const union decode_item arm_cccc_0000_____1001_table[] = { + /* Multiply and multiply-accumulate */ + + /* MUL cccc 0000 0000 xxxx xxxx xxxx 1001 xxxx */ + /* MULS cccc 0000 0001 xxxx xxxx xxxx 1001 xxxx */ + DECODE_EMULATEX (0x0fe000f0, 0x00000090, emulate_rd16rn12rm0rs8_rwflags_nopc, + REGS(NOPC, 0, NOPC, 0, NOPC)), + + /* MLA cccc 0000 0010 xxxx xxxx xxxx 1001 xxxx */ + /* MLAS cccc 0000 0011 xxxx xxxx xxxx 1001 xxxx */ + DECODE_OR (0x0fe000f0, 0x00200090), + /* MLS cccc 0000 0110 xxxx xxxx xxxx 1001 xxxx */ + DECODE_EMULATEX (0x0ff000f0, 0x00600090, emulate_rd16rn12rm0rs8_rwflags_nopc, + REGS(NOPC, NOPC, NOPC, 0, NOPC)), + + /* UMAAL cccc 0000 0100 xxxx xxxx xxxx 1001 xxxx */ + DECODE_OR (0x0ff000f0, 0x00400090), + /* UMULL cccc 0000 1000 xxxx xxxx xxxx 1001 xxxx */ + /* UMULLS cccc 0000 1001 xxxx xxxx xxxx 1001 xxxx */ + /* UMLAL cccc 0000 1010 xxxx xxxx xxxx 1001 xxxx */ + /* UMLALS cccc 0000 1011 xxxx xxxx xxxx 1001 xxxx */ + /* SMULL cccc 0000 1100 xxxx xxxx xxxx 1001 xxxx */ + /* SMULLS cccc 0000 1101 xxxx xxxx xxxx 1001 xxxx */ + /* SMLAL cccc 0000 1110 xxxx xxxx xxxx 1001 xxxx */ + /* SMLALS cccc 0000 1111 xxxx xxxx xxxx 1001 xxxx */ + DECODE_EMULATEX (0x0f8000f0, 0x00800090, emulate_rdlo12rdhi16rn0rm8_rwflags_nopc, + REGS(NOPC, NOPC, NOPC, 0, NOPC)), + + DECODE_END +}; + +static const union decode_item arm_cccc_0001_____1001_table[] = { + /* Synchronization primitives */ + +#if __LINUX_ARM_ARCH__ < 6 + /* Deprecated on ARMv6 and may be UNDEFINED on v7 */ + /* SMP/SWPB cccc 0001 0x00 xxxx xxxx xxxx 1001 xxxx */ + DECODE_EMULATEX (0x0fb000f0, 0x01000090, emulate_rd12rn16rm0_rwflags_nopc, + REGS(NOPC, NOPC, 0, 0, NOPC)), +#endif + /* LDREX/STREX{,D,B,H} cccc 0001 1xxx xxxx xxxx xxxx 1001 xxxx */ + /* And unallocated instructions... */ + DECODE_END +}; + +static const union decode_item arm_cccc_000x_____1xx1_table[] = { + /* Extra load/store instructions */ + + /* STRHT cccc 0000 xx10 xxxx xxxx xxxx 1011 xxxx */ + /* ??? cccc 0000 xx10 xxxx xxxx xxxx 11x1 xxxx */ + /* LDRHT cccc 0000 xx11 xxxx xxxx xxxx 1011 xxxx */ + /* LDRSBT cccc 0000 xx11 xxxx xxxx xxxx 1101 xxxx */ + /* LDRSHT cccc 0000 xx11 xxxx xxxx xxxx 1111 xxxx */ + DECODE_REJECT (0x0f200090, 0x00200090), + + /* LDRD/STRD lr,pc,{... cccc 000x x0x0 xxxx 111x xxxx 1101 xxxx */ + DECODE_REJECT (0x0e10e0d0, 0x0000e0d0), + + /* LDRD (register) cccc 000x x0x0 xxxx xxxx xxxx 1101 xxxx */ + /* STRD (register) cccc 000x x0x0 xxxx xxxx xxxx 1111 xxxx */ + DECODE_EMULATEX (0x0e5000d0, 0x000000d0, emulate_ldrdstrd, + REGS(NOPCWB, NOPCX, 0, 0, NOPC)), + + /* LDRD (immediate) cccc 000x x1x0 xxxx xxxx xxxx 1101 xxxx */ + /* STRD (immediate) cccc 000x x1x0 xxxx xxxx xxxx 1111 xxxx */ + DECODE_EMULATEX (0x0e5000d0, 0x004000d0, emulate_ldrdstrd, + REGS(NOPCWB, NOPCX, 0, 0, 0)), + + /* STRH (register) cccc 000x x0x0 xxxx xxxx xxxx 1011 xxxx */ + DECODE_EMULATEX (0x0e5000f0, 0x000000b0, emulate_str, + REGS(NOPCWB, NOPC, 0, 0, NOPC)), + + /* LDRH (register) cccc 000x x0x1 xxxx xxxx xxxx 1011 xxxx */ + /* LDRSB (register) cccc 000x x0x1 xxxx xxxx xxxx 1101 xxxx */ + /* LDRSH (register) cccc 000x x0x1 xxxx xxxx xxxx 1111 xxxx */ + DECODE_EMULATEX (0x0e500090, 0x00100090, emulate_ldr, + REGS(NOPCWB, NOPC, 0, 0, NOPC)), + + /* STRH (immediate) cccc 000x x1x0 xxxx xxxx xxxx 1011 xxxx */ + DECODE_EMULATEX (0x0e5000f0, 0x004000b0, emulate_str, + REGS(NOPCWB, NOPC, 0, 0, 0)), + + /* LDRH (immediate) cccc 000x x1x1 xxxx xxxx xxxx 1011 xxxx */ + /* LDRSB (immediate) cccc 000x x1x1 xxxx xxxx xxxx 1101 xxxx */ + /* LDRSH (immediate) cccc 000x x1x1 xxxx xxxx xxxx 1111 xxxx */ + DECODE_EMULATEX (0x0e500090, 0x00500090, emulate_ldr, + REGS(NOPCWB, NOPC, 0, 0, 0)), + + DECODE_END +}; + +static const union decode_item arm_cccc_000x_table[] = { + /* Data-processing (register) */ + + /* <op>S PC, ... cccc 000x xxx1 xxxx 1111 xxxx xxxx xxxx */ + DECODE_REJECT (0x0e10f000, 0x0010f000), + + /* MOV IP, SP 1110 0001 1010 0000 1100 0000 0000 1101 */ + DECODE_SIMULATE (0xffffffff, 0xe1a0c00d, simulate_mov_ipsp), + + /* TST (register) cccc 0001 0001 xxxx xxxx xxxx xxx0 xxxx */ + /* TEQ (register) cccc 0001 0011 xxxx xxxx xxxx xxx0 xxxx */ + /* CMP (register) cccc 0001 0101 xxxx xxxx xxxx xxx0 xxxx */ + /* CMN (register) cccc 0001 0111 xxxx xxxx xxxx xxx0 xxxx */ + DECODE_EMULATEX (0x0f900010, 0x01100000, emulate_rd12rn16rm0rs8_rwflags, + REGS(ANY, 0, 0, 0, ANY)), + + /* MOV (register) cccc 0001 101x xxxx xxxx xxxx xxx0 xxxx */ + /* MVN (register) cccc 0001 111x xxxx xxxx xxxx xxx0 xxxx */ + DECODE_EMULATEX (0x0fa00010, 0x01a00000, emulate_rd12rn16rm0rs8_rwflags, + REGS(0, ANY, 0, 0, ANY)), + + /* AND (register) cccc 0000 000x xxxx xxxx xxxx xxx0 xxxx */ + /* EOR (register) cccc 0000 001x xxxx xxxx xxxx xxx0 xxxx */ + /* SUB (register) cccc 0000 010x xxxx xxxx xxxx xxx0 xxxx */ + /* RSB (register) cccc 0000 011x xxxx xxxx xxxx xxx0 xxxx */ + /* ADD (register) cccc 0000 100x xxxx xxxx xxxx xxx0 xxxx */ + /* ADC (register) cccc 0000 101x xxxx xxxx xxxx xxx0 xxxx */ + /* SBC (register) cccc 0000 110x xxxx xxxx xxxx xxx0 xxxx */ + /* RSC (register) cccc 0000 111x xxxx xxxx xxxx xxx0 xxxx */ + /* ORR (register) cccc 0001 100x xxxx xxxx xxxx xxx0 xxxx */ + /* BIC (register) cccc 0001 110x xxxx xxxx xxxx xxx0 xxxx */ + DECODE_EMULATEX (0x0e000010, 0x00000000, emulate_rd12rn16rm0rs8_rwflags, + REGS(ANY, ANY, 0, 0, ANY)), + + /* TST (reg-shift reg) cccc 0001 0001 xxxx xxxx xxxx 0xx1 xxxx */ + /* TEQ (reg-shift reg) cccc 0001 0011 xxxx xxxx xxxx 0xx1 xxxx */ + /* CMP (reg-shift reg) cccc 0001 0101 xxxx xxxx xxxx 0xx1 xxxx */ + /* CMN (reg-shift reg) cccc 0001 0111 xxxx xxxx xxxx 0xx1 xxxx */ + DECODE_EMULATEX (0x0f900090, 0x01100010, emulate_rd12rn16rm0rs8_rwflags, + REGS(ANY, 0, NOPC, 0, ANY)), + + /* MOV (reg-shift reg) cccc 0001 101x xxxx xxxx xxxx 0xx1 xxxx */ + /* MVN (reg-shift reg) cccc 0001 111x xxxx xxxx xxxx 0xx1 xxxx */ + DECODE_EMULATEX (0x0fa00090, 0x01a00010, emulate_rd12rn16rm0rs8_rwflags, + REGS(0, ANY, NOPC, 0, ANY)), + + /* AND (reg-shift reg) cccc 0000 000x xxxx xxxx xxxx 0xx1 xxxx */ + /* EOR (reg-shift reg) cccc 0000 001x xxxx xxxx xxxx 0xx1 xxxx */ + /* SUB (reg-shift reg) cccc 0000 010x xxxx xxxx xxxx 0xx1 xxxx */ + /* RSB (reg-shift reg) cccc 0000 011x xxxx xxxx xxxx 0xx1 xxxx */ + /* ADD (reg-shift reg) cccc 0000 100x xxxx xxxx xxxx 0xx1 xxxx */ + /* ADC (reg-shift reg) cccc 0000 101x xxxx xxxx xxxx 0xx1 xxxx */ + /* SBC (reg-shift reg) cccc 0000 110x xxxx xxxx xxxx 0xx1 xxxx */ + /* RSC (reg-shift reg) cccc 0000 111x xxxx xxxx xxxx 0xx1 xxxx */ + /* ORR (reg-shift reg) cccc 0001 100x xxxx xxxx xxxx 0xx1 xxxx */ + /* BIC (reg-shift reg) cccc 0001 110x xxxx xxxx xxxx 0xx1 xxxx */ + DECODE_EMULATEX (0x0e000090, 0x00000010, emulate_rd12rn16rm0rs8_rwflags, + REGS(ANY, ANY, NOPC, 0, ANY)), + + DECODE_END +}; + +static const union decode_item arm_cccc_001x_table[] = { + /* Data-processing (immediate) */ + + /* MOVW cccc 0011 0000 xxxx xxxx xxxx xxxx xxxx */ + /* MOVT cccc 0011 0100 xxxx xxxx xxxx xxxx xxxx */ + DECODE_EMULATEX (0x0fb00000, 0x03000000, emulate_rd12rm0_noflags_nopc, + REGS(0, NOPC, 0, 0, 0)), + + /* YIELD cccc 0011 0010 0000 xxxx xxxx 0000 0001 */ + DECODE_OR (0x0fff00ff, 0x03200001), + /* SEV cccc 0011 0010 0000 xxxx xxxx 0000 0100 */ + DECODE_EMULATE (0x0fff00ff, 0x03200004, kprobe_emulate_none), + /* NOP cccc 0011 0010 0000 xxxx xxxx 0000 0000 */ + /* WFE cccc 0011 0010 0000 xxxx xxxx 0000 0010 */ + /* WFI cccc 0011 0010 0000 xxxx xxxx 0000 0011 */ + DECODE_SIMULATE (0x0fff00fc, 0x03200000, kprobe_simulate_nop), + /* DBG cccc 0011 0010 0000 xxxx xxxx ffff xxxx */ + /* unallocated hints cccc 0011 0010 0000 xxxx xxxx xxxx xxxx */ + /* MSR (immediate) cccc 0011 0x10 xxxx xxxx xxxx xxxx xxxx */ + DECODE_REJECT (0x0fb00000, 0x03200000), + + /* <op>S PC, ... cccc 001x xxx1 xxxx 1111 xxxx xxxx xxxx */ + DECODE_REJECT (0x0e10f000, 0x0210f000), + + /* TST (immediate) cccc 0011 0001 xxxx xxxx xxxx xxxx xxxx */ + /* TEQ (immediate) cccc 0011 0011 xxxx xxxx xxxx xxxx xxxx */ + /* CMP (immediate) cccc 0011 0101 xxxx xxxx xxxx xxxx xxxx */ + /* CMN (immediate) cccc 0011 0111 xxxx xxxx xxxx xxxx xxxx */ + DECODE_EMULATEX (0x0f900000, 0x03100000, emulate_rd12rn16rm0rs8_rwflags, + REGS(ANY, 0, 0, 0, 0)), + + /* MOV (immediate) cccc 0011 101x xxxx xxxx xxxx xxxx xxxx */ + /* MVN (immediate) cccc 0011 111x xxxx xxxx xxxx xxxx xxxx */ + DECODE_EMULATEX (0x0fa00000, 0x03a00000, emulate_rd12rn16rm0rs8_rwflags, + REGS(0, ANY, 0, 0, 0)), + + /* AND (immediate) cccc 0010 000x xxxx xxxx xxxx xxxx xxxx */ + /* EOR (immediate) cccc 0010 001x xxxx xxxx xxxx xxxx xxxx */ + /* SUB (immediate) cccc 0010 010x xxxx xxxx xxxx xxxx xxxx */ + /* RSB (immediate) cccc 0010 011x xxxx xxxx xxxx xxxx xxxx */ + /* ADD (immediate) cccc 0010 100x xxxx xxxx xxxx xxxx xxxx */ + /* ADC (immediate) cccc 0010 101x xxxx xxxx xxxx xxxx xxxx */ + /* SBC (immediate) cccc 0010 110x xxxx xxxx xxxx xxxx xxxx */ + /* RSC (immediate) cccc 0010 111x xxxx xxxx xxxx xxxx xxxx */ + /* ORR (immediate) cccc 0011 100x xxxx xxxx xxxx xxxx xxxx */ + /* BIC (immediate) cccc 0011 110x xxxx xxxx xxxx xxxx xxxx */ + DECODE_EMULATEX (0x0e000000, 0x02000000, emulate_rd12rn16rm0rs8_rwflags, + REGS(ANY, ANY, 0, 0, 0)), + + DECODE_END +}; + +static const union decode_item arm_cccc_0110_____xxx1_table[] = { + /* Media instructions */ + + /* SEL cccc 0110 1000 xxxx xxxx xxxx 1011 xxxx */ + DECODE_EMULATEX (0x0ff000f0, 0x068000b0, emulate_rd12rn16rm0_rwflags_nopc, + REGS(NOPC, NOPC, 0, 0, NOPC)), + + /* SSAT cccc 0110 101x xxxx xxxx xxxx xx01 xxxx */ + /* USAT cccc 0110 111x xxxx xxxx xxxx xx01 xxxx */ + DECODE_OR(0x0fa00030, 0x06a00010), + /* SSAT16 cccc 0110 1010 xxxx xxxx xxxx 0011 xxxx */ + /* USAT16 cccc 0110 1110 xxxx xxxx xxxx 0011 xxxx */ + DECODE_EMULATEX (0x0fb000f0, 0x06a00030, emulate_rd12rn16rm0_rwflags_nopc, + REGS(0, NOPC, 0, 0, NOPC)), + + /* REV cccc 0110 1011 xxxx xxxx xxxx 0011 xxxx */ + /* REV16 cccc 0110 1011 xxxx xxxx xxxx 1011 xxxx */ + /* RBIT cccc 0110 1111 xxxx xxxx xxxx 0011 xxxx */ + /* REVSH cccc 0110 1111 xxxx xxxx xxxx 1011 xxxx */ + DECODE_EMULATEX (0x0fb00070, 0x06b00030, emulate_rd12rm0_noflags_nopc, + REGS(0, NOPC, 0, 0, NOPC)), + + /* ??? cccc 0110 0x00 xxxx xxxx xxxx xxx1 xxxx */ + DECODE_REJECT (0x0fb00010, 0x06000010), + /* ??? cccc 0110 0xxx xxxx xxxx xxxx 1011 xxxx */ + DECODE_REJECT (0x0f8000f0, 0x060000b0), + /* ??? cccc 0110 0xxx xxxx xxxx xxxx 1101 xxxx */ + DECODE_REJECT (0x0f8000f0, 0x060000d0), + /* SADD16 cccc 0110 0001 xxxx xxxx xxxx 0001 xxxx */ + /* SADDSUBX cccc 0110 0001 xxxx xxxx xxxx 0011 xxxx */ + /* SSUBADDX cccc 0110 0001 xxxx xxxx xxxx 0101 xxxx */ + /* SSUB16 cccc 0110 0001 xxxx xxxx xxxx 0111 xxxx */ + /* SADD8 cccc 0110 0001 xxxx xxxx xxxx 1001 xxxx */ + /* SSUB8 cccc 0110 0001 xxxx xxxx xxxx 1111 xxxx */ + /* QADD16 cccc 0110 0010 xxxx xxxx xxxx 0001 xxxx */ + /* QADDSUBX cccc 0110 0010 xxxx xxxx xxxx 0011 xxxx */ + /* QSUBADDX cccc 0110 0010 xxxx xxxx xxxx 0101 xxxx */ + /* QSUB16 cccc 0110 0010 xxxx xxxx xxxx 0111 xxxx */ + /* QADD8 cccc 0110 0010 xxxx xxxx xxxx 1001 xxxx */ + /* QSUB8 cccc 0110 0010 xxxx xxxx xxxx 1111 xxxx */ + /* SHADD16 cccc 0110 0011 xxxx xxxx xxxx 0001 xxxx */ + /* SHADDSUBX cccc 0110 0011 xxxx xxxx xxxx 0011 xxxx */ + /* SHSUBADDX cccc 0110 0011 xxxx xxxx xxxx 0101 xxxx */ + /* SHSUB16 cccc 0110 0011 xxxx xxxx xxxx 0111 xxxx */ + /* SHADD8 cccc 0110 0011 xxxx xxxx xxxx 1001 xxxx */ + /* SHSUB8 cccc 0110 0011 xxxx xxxx xxxx 1111 xxxx */ + /* UADD16 cccc 0110 0101 xxxx xxxx xxxx 0001 xxxx */ + /* UADDSUBX cccc 0110 0101 xxxx xxxx xxxx 0011 xxxx */ + /* USUBADDX cccc 0110 0101 xxxx xxxx xxxx 0101 xxxx */ + /* USUB16 cccc 0110 0101 xxxx xxxx xxxx 0111 xxxx */ + /* UADD8 cccc 0110 0101 xxxx xxxx xxxx 1001 xxxx */ + /* USUB8 cccc 0110 0101 xxxx xxxx xxxx 1111 xxxx */ + /* UQADD16 cccc 0110 0110 xxxx xxxx xxxx 0001 xxxx */ + /* UQADDSUBX cccc 0110 0110 xxxx xxxx xxxx 0011 xxxx */ + /* UQSUBADDX cccc 0110 0110 xxxx xxxx xxxx 0101 xxxx */ + /* UQSUB16 cccc 0110 0110 xxxx xxxx xxxx 0111 xxxx */ + /* UQADD8 cccc 0110 0110 xxxx xxxx xxxx 1001 xxxx */ + /* UQSUB8 cccc 0110 0110 xxxx xxxx xxxx 1111 xxxx */ + /* UHADD16 cccc 0110 0111 xxxx xxxx xxxx 0001 xxxx */ + /* UHADDSUBX cccc 0110 0111 xxxx xxxx xxxx 0011 xxxx */ + /* UHSUBADDX cccc 0110 0111 xxxx xxxx xxxx 0101 xxxx */ + /* UHSUB16 cccc 0110 0111 xxxx xxxx xxxx 0111 xxxx */ + /* UHADD8 cccc 0110 0111 xxxx xxxx xxxx 1001 xxxx */ + /* UHSUB8 cccc 0110 0111 xxxx xxxx xxxx 1111 xxxx */ + DECODE_EMULATEX (0x0f800010, 0x06000010, emulate_rd12rn16rm0_rwflags_nopc, + REGS(NOPC, NOPC, 0, 0, NOPC)), + + /* PKHBT cccc 0110 1000 xxxx xxxx xxxx x001 xxxx */ + /* PKHTB cccc 0110 1000 xxxx xxxx xxxx x101 xxxx */ + DECODE_EMULATEX (0x0ff00030, 0x06800010, emulate_rd12rn16rm0_rwflags_nopc, + REGS(NOPC, NOPC, 0, 0, NOPC)), + + /* ??? cccc 0110 1001 xxxx xxxx xxxx 0111 xxxx */ + /* ??? cccc 0110 1101 xxxx xxxx xxxx 0111 xxxx */ + DECODE_REJECT (0x0fb000f0, 0x06900070), + + /* SXTB16 cccc 0110 1000 1111 xxxx xxxx 0111 xxxx */ + /* SXTB cccc 0110 1010 1111 xxxx xxxx 0111 xxxx */ + /* SXTH cccc 0110 1011 1111 xxxx xxxx 0111 xxxx */ + /* UXTB16 cccc 0110 1100 1111 xxxx xxxx 0111 xxxx */ + /* UXTB cccc 0110 1110 1111 xxxx xxxx 0111 xxxx */ + /* UXTH cccc 0110 1111 1111 xxxx xxxx 0111 xxxx */ + DECODE_EMULATEX (0x0f8f00f0, 0x068f0070, emulate_rd12rm0_noflags_nopc, + REGS(0, NOPC, 0, 0, NOPC)), + + /* SXTAB16 cccc 0110 1000 xxxx xxxx xxxx 0111 xxxx */ + /* SXTAB cccc 0110 1010 xxxx xxxx xxxx 0111 xxxx */ + /* SXTAH cccc 0110 1011 xxxx xxxx xxxx 0111 xxxx */ + /* UXTAB16 cccc 0110 1100 xxxx xxxx xxxx 0111 xxxx */ + /* UXTAB cccc 0110 1110 xxxx xxxx xxxx 0111 xxxx */ + /* UXTAH cccc 0110 1111 xxxx xxxx xxxx 0111 xxxx */ + DECODE_EMULATEX (0x0f8000f0, 0x06800070, emulate_rd12rn16rm0_rwflags_nopc, + REGS(NOPCX, NOPC, 0, 0, NOPC)), + + DECODE_END +}; + +static const union decode_item arm_cccc_0111_____xxx1_table[] = { + /* Media instructions */ + + /* UNDEFINED cccc 0111 1111 xxxx xxxx xxxx 1111 xxxx */ + DECODE_REJECT (0x0ff000f0, 0x07f000f0), + + /* SMLALD cccc 0111 0100 xxxx xxxx xxxx 00x1 xxxx */ + /* SMLSLD cccc 0111 0100 xxxx xxxx xxxx 01x1 xxxx */ + DECODE_EMULATEX (0x0ff00090, 0x07400010, emulate_rdlo12rdhi16rn0rm8_rwflags_nopc, + REGS(NOPC, NOPC, NOPC, 0, NOPC)), + + /* SMUAD cccc 0111 0000 xxxx 1111 xxxx 00x1 xxxx */ + /* SMUSD cccc 0111 0000 xxxx 1111 xxxx 01x1 xxxx */ + DECODE_OR (0x0ff0f090, 0x0700f010), + /* SMMUL cccc 0111 0101 xxxx 1111 xxxx 00x1 xxxx */ + DECODE_OR (0x0ff0f0d0, 0x0750f010), + /* USAD8 cccc 0111 1000 xxxx 1111 xxxx 0001 xxxx */ + DECODE_EMULATEX (0x0ff0f0f0, 0x0780f010, emulate_rd16rn12rm0rs8_rwflags_nopc, + REGS(NOPC, 0, NOPC, 0, NOPC)), + + /* SMLAD cccc 0111 0000 xxxx xxxx xxxx 00x1 xxxx */ + /* SMLSD cccc 0111 0000 xxxx xxxx xxxx 01x1 xxxx */ + DECODE_OR (0x0ff00090, 0x07000010), + /* SMMLA cccc 0111 0101 xxxx xxxx xxxx 00x1 xxxx */ + DECODE_OR (0x0ff000d0, 0x07500010), + /* USADA8 cccc 0111 1000 xxxx xxxx xxxx 0001 xxxx */ + DECODE_EMULATEX (0x0ff000f0, 0x07800010, emulate_rd16rn12rm0rs8_rwflags_nopc, + REGS(NOPC, NOPCX, NOPC, 0, NOPC)), + + /* SMMLS cccc 0111 0101 xxxx xxxx xxxx 11x1 xxxx */ + DECODE_EMULATEX (0x0ff000d0, 0x075000d0, emulate_rd16rn12rm0rs8_rwflags_nopc, + REGS(NOPC, NOPC, NOPC, 0, NOPC)), + + /* SBFX cccc 0111 101x xxxx xxxx xxxx x101 xxxx */ + /* UBFX cccc 0111 111x xxxx xxxx xxxx x101 xxxx */ + DECODE_EMULATEX (0x0fa00070, 0x07a00050, emulate_rd12rm0_noflags_nopc, + REGS(0, NOPC, 0, 0, NOPC)), + + /* BFC cccc 0111 110x xxxx xxxx xxxx x001 1111 */ + DECODE_EMULATEX (0x0fe0007f, 0x07c0001f, emulate_rd12rm0_noflags_nopc, + REGS(0, NOPC, 0, 0, 0)), + + /* BFI cccc 0111 110x xxxx xxxx xxxx x001 xxxx */ + DECODE_EMULATEX (0x0fe00070, 0x07c00010, emulate_rd12rm0_noflags_nopc, + REGS(0, NOPC, 0, 0, NOPCX)), + + DECODE_END +}; + +static const union decode_item arm_cccc_01xx_table[] = { + /* Load/store word and unsigned byte */ + + /* LDRB/STRB pc,[...] cccc 01xx x0xx xxxx xxxx xxxx xxxx xxxx */ + DECODE_REJECT (0x0c40f000, 0x0440f000), + + /* STRT cccc 01x0 x010 xxxx xxxx xxxx xxxx xxxx */ + /* LDRT cccc 01x0 x011 xxxx xxxx xxxx xxxx xxxx */ + /* STRBT cccc 01x0 x110 xxxx xxxx xxxx xxxx xxxx */ + /* LDRBT cccc 01x0 x111 xxxx xxxx xxxx xxxx xxxx */ + DECODE_REJECT (0x0d200000, 0x04200000), + + /* STR (immediate) cccc 010x x0x0 xxxx xxxx xxxx xxxx xxxx */ + /* STRB (immediate) cccc 010x x1x0 xxxx xxxx xxxx xxxx xxxx */ + DECODE_EMULATEX (0x0e100000, 0x04000000, emulate_str, + REGS(NOPCWB, ANY, 0, 0, 0)), + + /* LDR (immediate) cccc 010x x0x1 xxxx xxxx xxxx xxxx xxxx */ + /* LDRB (immediate) cccc 010x x1x1 xxxx xxxx xxxx xxxx xxxx */ + DECODE_EMULATEX (0x0e100000, 0x04100000, emulate_ldr, + REGS(NOPCWB, ANY, 0, 0, 0)), + + /* STR (register) cccc 011x x0x0 xxxx xxxx xxxx xxxx xxxx */ + /* STRB (register) cccc 011x x1x0 xxxx xxxx xxxx xxxx xxxx */ + DECODE_EMULATEX (0x0e100000, 0x06000000, emulate_str, + REGS(NOPCWB, ANY, 0, 0, NOPC)), + + /* LDR (register) cccc 011x x0x1 xxxx xxxx xxxx xxxx xxxx */ + /* LDRB (register) cccc 011x x1x1 xxxx xxxx xxxx xxxx xxxx */ + DECODE_EMULATEX (0x0e100000, 0x06100000, emulate_ldr, + REGS(NOPCWB, ANY, 0, 0, NOPC)), + + DECODE_END +}; + +static const union decode_item arm_cccc_100x_table[] = { + /* Block data transfer instructions */ + + /* LDM cccc 100x x0x1 xxxx xxxx xxxx xxxx xxxx */ + /* STM cccc 100x x0x0 xxxx xxxx xxxx xxxx xxxx */ + DECODE_CUSTOM (0x0e400000, 0x08000000, kprobe_decode_ldmstm), + + /* STM (user registers) cccc 100x x1x0 xxxx xxxx xxxx xxxx xxxx */ + /* LDM (user registers) cccc 100x x1x1 xxxx 0xxx xxxx xxxx xxxx */ + /* LDM (exception ret) cccc 100x x1x1 xxxx 1xxx xxxx xxxx xxxx */ + DECODE_END +}; + +const union decode_item kprobe_decode_arm_table[] = { + /* + * Unconditional instructions + * 1111 xxxx xxxx xxxx xxxx xxxx xxxx xxxx + */ + DECODE_TABLE (0xf0000000, 0xf0000000, arm_1111_table), + + /* + * Miscellaneous instructions + * cccc 0001 0xx0 xxxx xxxx xxxx 0xxx xxxx + */ + DECODE_TABLE (0x0f900080, 0x01000000, arm_cccc_0001_0xx0____0xxx_table), + + /* + * Halfword multiply and multiply-accumulate + * cccc 0001 0xx0 xxxx xxxx xxxx 1xx0 xxxx + */ + DECODE_TABLE (0x0f900090, 0x01000080, arm_cccc_0001_0xx0____1xx0_table), + + /* + * Multiply and multiply-accumulate + * cccc 0000 xxxx xxxx xxxx xxxx 1001 xxxx + */ + DECODE_TABLE (0x0f0000f0, 0x00000090, arm_cccc_0000_____1001_table), + + /* + * Synchronization primitives + * cccc 0001 xxxx xxxx xxxx xxxx 1001 xxxx + */ + DECODE_TABLE (0x0f0000f0, 0x01000090, arm_cccc_0001_____1001_table), + + /* + * Extra load/store instructions + * cccc 000x xxxx xxxx xxxx xxxx 1xx1 xxxx + */ + DECODE_TABLE (0x0e000090, 0x00000090, arm_cccc_000x_____1xx1_table), + + /* + * Data-processing (register) + * cccc 000x xxxx xxxx xxxx xxxx xxx0 xxxx + * Data-processing (register-shifted register) + * cccc 000x xxxx xxxx xxxx xxxx 0xx1 xxxx + */ + DECODE_TABLE (0x0e000000, 0x00000000, arm_cccc_000x_table), + + /* + * Data-processing (immediate) + * cccc 001x xxxx xxxx xxxx xxxx xxxx xxxx + */ + DECODE_TABLE (0x0e000000, 0x02000000, arm_cccc_001x_table), + + /* + * Media instructions + * cccc 011x xxxx xxxx xxxx xxxx xxx1 xxxx + */ + DECODE_TABLE (0x0f000010, 0x06000010, arm_cccc_0110_____xxx1_table), + DECODE_TABLE (0x0f000010, 0x07000010, arm_cccc_0111_____xxx1_table), + + /* + * Load/store word and unsigned byte + * cccc 01xx xxxx xxxx xxxx xxxx xxxx xxxx + */ + DECODE_TABLE (0x0c000000, 0x04000000, arm_cccc_01xx_table), + + /* + * Block data transfer instructions + * cccc 100x xxxx xxxx xxxx xxxx xxxx xxxx + */ + DECODE_TABLE (0x0e000000, 0x08000000, arm_cccc_100x_table), + + /* B cccc 1010 xxxx xxxx xxxx xxxx xxxx xxxx */ + /* BL cccc 1011 xxxx xxxx xxxx xxxx xxxx xxxx */ + DECODE_SIMULATE (0x0e000000, 0x0a000000, simulate_bbl), + + /* + * Supervisor Call, and coprocessor instructions + */ + + /* MCRR cccc 1100 0100 xxxx xxxx xxxx xxxx xxxx */ + /* MRRC cccc 1100 0101 xxxx xxxx xxxx xxxx xxxx */ + /* LDC cccc 110x xxx1 xxxx xxxx xxxx xxxx xxxx */ + /* STC cccc 110x xxx0 xxxx xxxx xxxx xxxx xxxx */ + /* CDP cccc 1110 xxxx xxxx xxxx xxxx xxx0 xxxx */ + /* MCR cccc 1110 xxx0 xxxx xxxx xxxx xxx1 xxxx */ + /* MRC cccc 1110 xxx1 xxxx xxxx xxxx xxx1 xxxx */ + /* SVC cccc 1111 xxxx xxxx xxxx xxxx xxxx xxxx */ + DECODE_REJECT (0x0c000000, 0x0c000000), + + DECODE_END +}; +#ifdef CONFIG_ARM_KPROBES_TEST_MODULE +EXPORT_SYMBOL_GPL(kprobe_decode_arm_table); +#endif + +static void __kprobes arm_singlestep(struct kprobe *p, struct pt_regs *regs) +{ + regs->ARM_pc += 4; + p->ainsn.insn_handler(p, regs); +} + +/* Return: + * INSN_REJECTED If instruction is one not allowed to kprobe, + * INSN_GOOD If instruction is supported and uses instruction slot, + * INSN_GOOD_NO_SLOT If instruction is supported but doesn't use its slot. + * + * For instructions we don't want to kprobe (INSN_REJECTED return result): + * These are generally ones that modify the processor state making + * them "hard" to simulate such as switches processor modes or + * make accesses in alternate modes. Any of these could be simulated + * if the work was put into it, but low return considering they + * should also be very rare. + */ +enum kprobe_insn __kprobes +arm_kprobe_decode_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi) +{ + asi->insn_singlestep = arm_singlestep; + asi->insn_check_cc = kprobe_condition_checks[insn>>28]; + return kprobe_decode_insn(insn, asi, kprobe_decode_arm_table, false); +} diff --git a/arch/arm/kernel/probes-arm.h b/arch/arm/kernel/probes-arm.h new file mode 100644 index 000000000000..86084727d36d --- /dev/null +++ b/arch/arm/kernel/probes-arm.h @@ -0,0 +1,38 @@ +/* + * arch/arm/kernel/probes-arm.h + * + * Copyright 2013 Linaro Ltd. + * Written by: David A. Long + * + * The code contained herein is licensed under the GNU General Public + * License. You may obtain a copy of the GNU General Public License + * Version 2 or later at the following locations: + * + * http://www.opensource.org/licenses/gpl-license.html + * http://www.gnu.org/copyleft/gpl.html + */ + +#ifndef _ARM_KERNEL_PROBES_ARM_H +#define _ARM_KERNEL_PROBES_ARM_H + +void __kprobes simulate_bbl(struct kprobe *p, struct pt_regs *regs); +void __kprobes simulate_blx1(struct kprobe *p, struct pt_regs *regs); +void __kprobes simulate_blx2bx(struct kprobe *p, struct pt_regs *regs); +void __kprobes simulate_mrs(struct kprobe *p, struct pt_regs *regs); +void __kprobes simulate_mov_ipsp(struct kprobe *p, struct pt_regs *regs); + +void __kprobes emulate_ldrdstrd(struct kprobe *p, struct pt_regs *regs); +void __kprobes emulate_ldr(struct kprobe *p, struct pt_regs *regs); +void __kprobes emulate_str(struct kprobe *p, struct pt_regs *regs); +void __kprobes emulate_rd12rn16rm0rs8_rwflags(struct kprobe *p, + struct pt_regs *regs); +void __kprobes emulate_rd12rn16rm0_rwflags_nopc(struct kprobe *p, + struct pt_regs *regs); +void __kprobes emulate_rd16rn12rm0rs8_rwflags_nopc(struct kprobe *p, + struct pt_regs *regs); +void __kprobes emulate_rd12rm0_noflags_nopc(struct kprobe *p, + struct pt_regs *regs); +void __kprobes emulate_rdlo12rdhi16rn0rm8_rwflags_nopc(struct kprobe *p, + struct pt_regs *regs); + +#endif diff --git a/arch/arm/kernel/probes.c b/arch/arm/kernel/probes.c new file mode 100644 index 000000000000..3a63f8f83cf8 --- /dev/null +++ b/arch/arm/kernel/probes.c @@ -0,0 +1,443 @@ +/* + * arch/arm/kernel/probes.c + * + * Copyright (C) 2011 Jon Medhurst <tixy@yxit.co.uk>. + * + * Some contents moved here from arch/arm/include/asm/kprobes-arm.c which is + * Copyright (C) 2006, 2007 Motorola Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/kernel.h> +#include <linux/types.h> +#include <linux/kprobes.h> +#include <asm/system_info.h> +#include <asm/ptrace.h> +#include <linux/bug.h> + +#include "kprobes.h" + + +#ifndef find_str_pc_offset + +/* + * For STR and STM instructions, an ARM core may choose to use either + * a +8 or a +12 displacement from the current instruction's address. + * Whichever value is chosen for a given core, it must be the same for + * both instructions and may not change. This function measures it. + */ + +int str_pc_offset; + +void __init find_str_pc_offset(void) +{ + int addr, scratch, ret; + + __asm__ ( + "sub %[ret], pc, #4 \n\t" + "str pc, %[addr] \n\t" + "ldr %[scr], %[addr] \n\t" + "sub %[ret], %[scr], %[ret] \n\t" + : [ret] "=r" (ret), [scr] "=r" (scratch), [addr] "+m" (addr)); + + str_pc_offset = ret; +} + +#endif /* !find_str_pc_offset */ + + +#ifndef test_load_write_pc_interworking + +bool load_write_pc_interworks; + +void __init test_load_write_pc_interworking(void) +{ + int arch = cpu_architecture(); + BUG_ON(arch == CPU_ARCH_UNKNOWN); + load_write_pc_interworks = arch >= CPU_ARCH_ARMv5T; +} + +#endif /* !test_load_write_pc_interworking */ + + +#ifndef test_alu_write_pc_interworking + +bool alu_write_pc_interworks; + +void __init test_alu_write_pc_interworking(void) +{ + int arch = cpu_architecture(); + BUG_ON(arch == CPU_ARCH_UNKNOWN); + alu_write_pc_interworks = arch >= CPU_ARCH_ARMv7; +} + +#endif /* !test_alu_write_pc_interworking */ + + +void __init arm_kprobe_decode_init(void) +{ + find_str_pc_offset(); + test_load_write_pc_interworking(); + test_alu_write_pc_interworking(); +} + + +static unsigned long __kprobes __check_eq(unsigned long cpsr) +{ + return cpsr & PSR_Z_BIT; +} + +static unsigned long __kprobes __check_ne(unsigned long cpsr) +{ + return (~cpsr) & PSR_Z_BIT; +} + +static unsigned long __kprobes __check_cs(unsigned long cpsr) +{ + return cpsr & PSR_C_BIT; +} + +static unsigned long __kprobes __check_cc(unsigned long cpsr) +{ + return (~cpsr) & PSR_C_BIT; +} + +static unsigned long __kprobes __check_mi(unsigned long cpsr) +{ + return cpsr & PSR_N_BIT; +} + +static unsigned long __kprobes __check_pl(unsigned long cpsr) +{ + return (~cpsr) & PSR_N_BIT; +} + +static unsigned long __kprobes __check_vs(unsigned long cpsr) +{ + return cpsr & PSR_V_BIT; +} + +static unsigned long __kprobes __check_vc(unsigned long cpsr) +{ + return (~cpsr) & PSR_V_BIT; +} + +static unsigned long __kprobes __check_hi(unsigned long cpsr) +{ + cpsr &= ~(cpsr >> 1); /* PSR_C_BIT &= ~PSR_Z_BIT */ + return cpsr & PSR_C_BIT; +} + +static unsigned long __kprobes __check_ls(unsigned long cpsr) +{ + cpsr &= ~(cpsr >> 1); /* PSR_C_BIT &= ~PSR_Z_BIT */ + return (~cpsr) & PSR_C_BIT; +} + +static unsigned long __kprobes __check_ge(unsigned long cpsr) +{ + cpsr ^= (cpsr << 3); /* PSR_N_BIT ^= PSR_V_BIT */ + return (~cpsr) & PSR_N_BIT; +} + +static unsigned long __kprobes __check_lt(unsigned long cpsr) +{ + cpsr ^= (cpsr << 3); /* PSR_N_BIT ^= PSR_V_BIT */ + return cpsr & PSR_N_BIT; +} + +static unsigned long __kprobes __check_gt(unsigned long cpsr) +{ + unsigned long temp = cpsr ^ (cpsr << 3); /* PSR_N_BIT ^= PSR_V_BIT */ + temp |= (cpsr << 1); /* PSR_N_BIT |= PSR_Z_BIT */ + return (~temp) & PSR_N_BIT; +} + +static unsigned long __kprobes __check_le(unsigned long cpsr) +{ + unsigned long temp = cpsr ^ (cpsr << 3); /* PSR_N_BIT ^= PSR_V_BIT */ + temp |= (cpsr << 1); /* PSR_N_BIT |= PSR_Z_BIT */ + return temp & PSR_N_BIT; +} + +static unsigned long __kprobes __check_al(unsigned long cpsr) +{ + return true; +} + +kprobe_check_cc * const kprobe_condition_checks[16] = { + &__check_eq, &__check_ne, &__check_cs, &__check_cc, + &__check_mi, &__check_pl, &__check_vs, &__check_vc, + &__check_hi, &__check_ls, &__check_ge, &__check_lt, + &__check_gt, &__check_le, &__check_al, &__check_al +}; + + +void __kprobes kprobe_simulate_nop(struct kprobe *p, struct pt_regs *regs) +{ +} + +void __kprobes kprobe_emulate_none(struct kprobe *p, struct pt_regs *regs) +{ + p->ainsn.insn_fn(); +} + +/* + * Prepare an instruction slot to receive an instruction for emulating. + * This is done by placing a subroutine return after the location where the + * instruction will be placed. We also modify ARM instructions to be + * unconditional as the condition code will already be checked before any + * emulation handler is called. + */ +static kprobe_opcode_t __kprobes +prepare_emulated_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi, + bool thumb) +{ +#ifdef CONFIG_THUMB2_KERNEL + if (thumb) { + u16 *thumb_insn = (u16 *)asi->insn; + thumb_insn[1] = 0x4770; /* Thumb bx lr */ + thumb_insn[2] = 0x4770; /* Thumb bx lr */ + return insn; + } + asi->insn[1] = 0xe12fff1e; /* ARM bx lr */ +#else + asi->insn[1] = 0xe1a0f00e; /* mov pc, lr */ +#endif + /* Make an ARM instruction unconditional */ + if (insn < 0xe0000000) + insn = (insn | 0xe0000000) & ~0x10000000; + return insn; +} + +/* + * Write a (probably modified) instruction into the slot previously prepared by + * prepare_emulated_insn + */ +static void __kprobes +set_emulated_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi, + bool thumb) +{ +#ifdef CONFIG_THUMB2_KERNEL + if (thumb) { + u16 *ip = (u16 *)asi->insn; + if (is_wide_instruction(insn)) + *ip++ = insn >> 16; + *ip++ = insn; + return; + } +#endif + asi->insn[0] = insn; +} + +/* + * When we modify the register numbers encoded in an instruction to be emulated, + * the new values come from this define. For ARM and 32-bit Thumb instructions + * this gives... + * + * bit position 16 12 8 4 0 + * ---------------+---+---+---+---+---+ + * register r2 r0 r1 -- r3 + */ +#define INSN_NEW_BITS 0x00020103 + +/* Each nibble has same value as that at INSN_NEW_BITS bit 16 */ +#define INSN_SAMEAS16_BITS 0x22222222 + +/* + * Validate and modify each of the registers encoded in an instruction. + * + * Each nibble in regs contains a value from enum decode_reg_type. For each + * non-zero value, the corresponding nibble in pinsn is validated and modified + * according to the type. + */ +static bool __kprobes decode_regs(kprobe_opcode_t *pinsn, u32 regs) +{ + kprobe_opcode_t insn = *pinsn; + kprobe_opcode_t mask = 0xf; /* Start at least significant nibble */ + + for (; regs != 0; regs >>= 4, mask <<= 4) { + + kprobe_opcode_t new_bits = INSN_NEW_BITS; + + switch (regs & 0xf) { + + case REG_TYPE_NONE: + /* Nibble not a register, skip to next */ + continue; + + case REG_TYPE_ANY: + /* Any register is allowed */ + break; + + case REG_TYPE_SAMEAS16: + /* Replace register with same as at bit position 16 */ + new_bits = INSN_SAMEAS16_BITS; + break; + + case REG_TYPE_SP: + /* Only allow SP (R13) */ + if ((insn ^ 0xdddddddd) & mask) + goto reject; + break; + + case REG_TYPE_PC: + /* Only allow PC (R15) */ + if ((insn ^ 0xffffffff) & mask) + goto reject; + break; + + case REG_TYPE_NOSP: + /* Reject SP (R13) */ + if (((insn ^ 0xdddddddd) & mask) == 0) + goto reject; + break; + + case REG_TYPE_NOSPPC: + case REG_TYPE_NOSPPCX: + /* Reject SP and PC (R13 and R15) */ + if (((insn ^ 0xdddddddd) & 0xdddddddd & mask) == 0) + goto reject; + break; + + case REG_TYPE_NOPCWB: + if (!is_writeback(insn)) + break; /* No writeback, so any register is OK */ + /* fall through... */ + case REG_TYPE_NOPC: + case REG_TYPE_NOPCX: + /* Reject PC (R15) */ + if (((insn ^ 0xffffffff) & mask) == 0) + goto reject; + break; + } + + /* Replace value of nibble with new register number... */ + insn &= ~mask; + insn |= new_bits & mask; + } + + *pinsn = insn; + return true; + +reject: + return false; +} + +static const int decode_struct_sizes[NUM_DECODE_TYPES] = { + [DECODE_TYPE_TABLE] = sizeof(struct decode_table), + [DECODE_TYPE_CUSTOM] = sizeof(struct decode_custom), + [DECODE_TYPE_SIMULATE] = sizeof(struct decode_simulate), + [DECODE_TYPE_EMULATE] = sizeof(struct decode_emulate), + [DECODE_TYPE_OR] = sizeof(struct decode_or), + [DECODE_TYPE_REJECT] = sizeof(struct decode_reject) +}; + +/* + * kprobe_decode_insn operates on data tables in order to decode an ARM + * architecture instruction onto which a kprobe has been placed. + * + * These instruction decoding tables are a concatenation of entries each + * of which consist of one of the following structs: + * + * decode_table + * decode_custom + * decode_simulate + * decode_emulate + * decode_or + * decode_reject + * + * Each of these starts with a struct decode_header which has the following + * fields: + * + * type_regs + * mask + * value + * + * The least significant DECODE_TYPE_BITS of type_regs contains a value + * from enum decode_type, this indicates which of the decode_* structs + * the entry contains. The value DECODE_TYPE_END indicates the end of the + * table. + * + * When the table is parsed, each entry is checked in turn to see if it + * matches the instruction to be decoded using the test: + * + * (insn & mask) == value + * + * If no match is found before the end of the table is reached then decoding + * fails with INSN_REJECTED. + * + * When a match is found, decode_regs() is called to validate and modify each + * of the registers encoded in the instruction; the data it uses to do this + * is (type_regs >> DECODE_TYPE_BITS). A validation failure will cause decoding + * to fail with INSN_REJECTED. + * + * Once the instruction has passed the above tests, further processing + * depends on the type of the table entry's decode struct. + * + */ +int __kprobes +kprobe_decode_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi, + const union decode_item *table, bool thumb) +{ + const struct decode_header *h = (struct decode_header *)table; + const struct decode_header *next; + bool matched = false; + + insn = prepare_emulated_insn(insn, asi, thumb); + + for (;; h = next) { + enum decode_type type = h->type_regs.bits & DECODE_TYPE_MASK; + u32 regs = h->type_regs.bits >> DECODE_TYPE_BITS; + + if (type == DECODE_TYPE_END) + return INSN_REJECTED; + + next = (struct decode_header *) + ((uintptr_t)h + decode_struct_sizes[type]); + + if (!matched && (insn & h->mask.bits) != h->value.bits) + continue; + + if (!decode_regs(&insn, regs)) + return INSN_REJECTED; + + switch (type) { + + case DECODE_TYPE_TABLE: { + struct decode_table *d = (struct decode_table *)h; + next = (struct decode_header *)d->table.table; + break; + } + + case DECODE_TYPE_CUSTOM: { + struct decode_custom *d = (struct decode_custom *)h; + return (*d->decoder.decoder)(insn, asi); + } + + case DECODE_TYPE_SIMULATE: { + struct decode_simulate *d = (struct decode_simulate *)h; + asi->insn_handler = d->handler.handler; + return INSN_GOOD_NO_SLOT; + } + + case DECODE_TYPE_EMULATE: { + struct decode_emulate *d = (struct decode_emulate *)h; + asi->insn_handler = d->handler.handler; + set_emulated_insn(insn, asi, thumb); + return INSN_GOOD; + } + + case DECODE_TYPE_OR: + matched = true; + break; + + case DECODE_TYPE_REJECT: + default: + return INSN_REJECTED; + } + } +} diff --git a/arch/arm/kernel/probes.h b/arch/arm/kernel/probes.h new file mode 100644 index 000000000000..17f656011aa3 --- /dev/null +++ b/arch/arm/kernel/probes.h @@ -0,0 +1,397 @@ +/* + * arch/arm/kernel/probes.h + * + * Copyright (C) 2011 Jon Medhurst <tixy@yxit.co.uk>. + * + * Some contents moved here from arch/arm/include/asm/kprobes.h which is + * Copyright (C) 2006, 2007 Motorola Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + */ + +#ifndef _ARM_KERNEL_PROBES_H +#define _ARM_KERNEL_PROBES_H + +#include <linux/types.h> +#include <linux/stddef.h> +#include <linux/kprobes.h> + +#if __LINUX_ARM_ARCH__ >= 7 + +/* str_pc_offset is architecturally defined from ARMv7 onwards */ +#define str_pc_offset 8 +#define find_str_pc_offset() + +#else /* __LINUX_ARM_ARCH__ < 7 */ + +/* We need a run-time check to determine str_pc_offset */ +extern int str_pc_offset; +void __init find_str_pc_offset(void); + +#endif + + +/* + * Update ITSTATE after normal execution of an IT block instruction. + * + * The 8 IT state bits are split into two parts in CPSR: + * ITSTATE<1:0> are in CPSR<26:25> + * ITSTATE<7:2> are in CPSR<15:10> + */ +static inline unsigned long it_advance(unsigned long cpsr) + { + if ((cpsr & 0x06000400) == 0) { + /* ITSTATE<2:0> == 0 means end of IT block, so clear IT state */ + cpsr &= ~PSR_IT_MASK; + } else { + /* We need to shift left ITSTATE<4:0> */ + const unsigned long mask = 0x06001c00; /* Mask ITSTATE<4:0> */ + unsigned long it = cpsr & mask; + it <<= 1; + it |= it >> (27 - 10); /* Carry ITSTATE<2> to correct place */ + it &= mask; + cpsr &= ~mask; + cpsr |= it; + } + return cpsr; +} + +static inline void __kprobes bx_write_pc(long pcv, struct pt_regs *regs) +{ + long cpsr = regs->ARM_cpsr; + if (pcv & 0x1) { + cpsr |= PSR_T_BIT; + pcv &= ~0x1; + } else { + cpsr &= ~PSR_T_BIT; + pcv &= ~0x2; /* Avoid UNPREDICTABLE address allignment */ + } + regs->ARM_cpsr = cpsr; + regs->ARM_pc = pcv; +} + + +#if __LINUX_ARM_ARCH__ >= 6 + +/* Kernels built for >= ARMv6 should never run on <= ARMv5 hardware, so... */ +#define load_write_pc_interworks true +#define test_load_write_pc_interworking() + +#else /* __LINUX_ARM_ARCH__ < 6 */ + +/* We need run-time testing to determine if load_write_pc() should interwork. */ +extern bool load_write_pc_interworks; +void __init test_load_write_pc_interworking(void); + +#endif + +static inline void __kprobes load_write_pc(long pcv, struct pt_regs *regs) +{ + if (load_write_pc_interworks) + bx_write_pc(pcv, regs); + else + regs->ARM_pc = pcv; +} + + +#if __LINUX_ARM_ARCH__ >= 7 + +#define alu_write_pc_interworks true +#define test_alu_write_pc_interworking() + +#elif __LINUX_ARM_ARCH__ <= 5 + +/* Kernels built for <= ARMv5 should never run on >= ARMv6 hardware, so... */ +#define alu_write_pc_interworks false +#define test_alu_write_pc_interworking() + +#else /* __LINUX_ARM_ARCH__ == 6 */ + +/* We could be an ARMv6 binary on ARMv7 hardware so we need a run-time check. */ +extern bool alu_write_pc_interworks; +void __init test_alu_write_pc_interworking(void); + +#endif /* __LINUX_ARM_ARCH__ == 6 */ + +static inline void __kprobes alu_write_pc(long pcv, struct pt_regs *regs) +{ + if (alu_write_pc_interworks) + bx_write_pc(pcv, regs); + else + regs->ARM_pc = pcv; +} + + +void __kprobes kprobe_simulate_nop(struct kprobe *p, struct pt_regs *regs); +void __kprobes kprobe_emulate_none(struct kprobe *p, struct pt_regs *regs); + +enum kprobe_insn __kprobes +kprobe_decode_ldmstm(kprobe_opcode_t insn, struct arch_specific_insn *asi); + +/* + * Test if load/store instructions writeback the address register. + * if P (bit 24) == 0 or W (bit 21) == 1 + */ +#define is_writeback(insn) ((insn ^ 0x01000000) & 0x01200000) + +/* + * The following definitions and macros are used to build instruction + * decoding tables for use by kprobe_decode_insn. + * + * These tables are a concatenation of entries each of which consist of one of + * the decode_* structs. All of the fields in every type of decode structure + * are of the union type decode_item, therefore the entire decode table can be + * viewed as an array of these and declared like: + * + * static const union decode_item table_name[] = {}; + * + * In order to construct each entry in the table, macros are used to + * initialise a number of sequential decode_item values in a layout which + * matches the relevant struct. E.g. DECODE_SIMULATE initialise a struct + * decode_simulate by initialising four decode_item objects like this... + * + * {.bits = _type}, + * {.bits = _mask}, + * {.bits = _value}, + * {.handler = _handler}, + * + * Initialising a specified member of the union means that the compiler + * will produce a warning if the argument is of an incorrect type. + * + * Below is a list of each of the macros used to initialise entries and a + * description of the action performed when that entry is matched to an + * instruction. A match is found when (instruction & mask) == value. + * + * DECODE_TABLE(mask, value, table) + * Instruction decoding jumps to parsing the new sub-table 'table'. + * + * DECODE_CUSTOM(mask, value, decoder) + * The custom function 'decoder' is called to the complete decoding + * of an instruction. + * + * DECODE_SIMULATE(mask, value, handler) + * Set the probes instruction handler to 'handler', this will be used + * to simulate the instruction when the probe is hit. Decoding returns + * with INSN_GOOD_NO_SLOT. + * + * DECODE_EMULATE(mask, value, handler) + * Set the probes instruction handler to 'handler', this will be used + * to emulate the instruction when the probe is hit. The modified + * instruction (see below) is placed in the probes instruction slot so it + * may be called by the emulation code. Decoding returns with INSN_GOOD. + * + * DECODE_REJECT(mask, value) + * Instruction decoding fails with INSN_REJECTED + * + * DECODE_OR(mask, value) + * This allows the mask/value test of multiple table entries to be + * logically ORed. Once an 'or' entry is matched the decoding action to + * be performed is that of the next entry which isn't an 'or'. E.g. + * + * DECODE_OR (mask1, value1) + * DECODE_OR (mask2, value2) + * DECODE_SIMULATE (mask3, value3, simulation_handler) + * + * This means that if any of the three mask/value pairs match the + * instruction being decoded, then 'simulation_handler' will be used + * for it. + * + * Both the SIMULATE and EMULATE macros have a second form which take an + * additional 'regs' argument. + * + * DECODE_SIMULATEX(mask, value, handler, regs) + * DECODE_EMULATEX (mask, value, handler, regs) + * + * These are used to specify what kind of CPU register is encoded in each of the + * least significant 5 nibbles of the instruction being decoded. The regs value + * is specified using the REGS macro, this takes any of the REG_TYPE_* values + * from enum decode_reg_type as arguments; only the '*' part of the name is + * given. E.g. + * + * REGS(0, ANY, NOPC, 0, ANY) + * + * This indicates an instruction is encoded like: + * + * bits 19..16 ignore + * bits 15..12 any register allowed here + * bits 11.. 8 any register except PC allowed here + * bits 7.. 4 ignore + * bits 3.. 0 any register allowed here + * + * This register specification is checked after a decode table entry is found to + * match an instruction (through the mask/value test). Any invalid register then + * found in the instruction will cause decoding to fail with INSN_REJECTED. In + * the above example this would happen if bits 11..8 of the instruction were + * 1111, indicating R15 or PC. + * + * As well as checking for legal combinations of registers, this data is also + * used to modify the registers encoded in the instructions so that an + * emulation routines can use it. (See decode_regs() and INSN_NEW_BITS.) + * + * Here is a real example which matches ARM instructions of the form + * "AND <Rd>,<Rn>,<Rm>,<shift> <Rs>" + * + * DECODE_EMULATEX (0x0e000090, 0x00000010, emulate_rd12rn16rm0rs8_rwflags, + * REGS(ANY, ANY, NOPC, 0, ANY)), + * ^ ^ ^ ^ + * Rn Rd Rs Rm + * + * Decoding the instruction "AND R4, R5, R6, ASL R15" will be rejected because + * Rs == R15 + * + * Decoding the instruction "AND R4, R5, R6, ASL R7" will be accepted and the + * instruction will be modified to "AND R0, R2, R3, ASL R1" and then placed into + * the kprobes instruction slot. This can then be called later by the handler + * function emulate_rd12rn16rm0rs8_rwflags in order to simulate the instruction. + */ + +enum decode_type { + DECODE_TYPE_END, + DECODE_TYPE_TABLE, + DECODE_TYPE_CUSTOM, + DECODE_TYPE_SIMULATE, + DECODE_TYPE_EMULATE, + DECODE_TYPE_OR, + DECODE_TYPE_REJECT, + NUM_DECODE_TYPES /* Must be last enum */ +}; + +#define DECODE_TYPE_BITS 4 +#define DECODE_TYPE_MASK ((1 << DECODE_TYPE_BITS) - 1) + +enum decode_reg_type { + REG_TYPE_NONE = 0, /* Not a register, ignore */ + REG_TYPE_ANY, /* Any register allowed */ + REG_TYPE_SAMEAS16, /* Register should be same as that at bits 19..16 */ + REG_TYPE_SP, /* Register must be SP */ + REG_TYPE_PC, /* Register must be PC */ + REG_TYPE_NOSP, /* Register must not be SP */ + REG_TYPE_NOSPPC, /* Register must not be SP or PC */ + REG_TYPE_NOPC, /* Register must not be PC */ + REG_TYPE_NOPCWB, /* No PC if load/store write-back flag also set */ + + /* The following types are used when the encoding for PC indicates + * another instruction form. This distiction only matters for test + * case coverage checks. + */ + REG_TYPE_NOPCX, /* Register must not be PC */ + REG_TYPE_NOSPPCX, /* Register must not be SP or PC */ + + /* Alias to allow '0' arg to be used in REGS macro. */ + REG_TYPE_0 = REG_TYPE_NONE +}; + +#define REGS(r16, r12, r8, r4, r0) \ + (((REG_TYPE_##r16) << 16) + \ + ((REG_TYPE_##r12) << 12) + \ + ((REG_TYPE_##r8) << 8) + \ + ((REG_TYPE_##r4) << 4) + \ + (REG_TYPE_##r0)) + +union decode_item { + u32 bits; + const union decode_item *table; + kprobe_insn_handler_t *handler; + kprobe_decode_insn_t *decoder; +}; + + +#define DECODE_END \ + {.bits = DECODE_TYPE_END} + + +struct decode_header { + union decode_item type_regs; + union decode_item mask; + union decode_item value; +}; + +#define DECODE_HEADER(_type, _mask, _value, _regs) \ + {.bits = (_type) | ((_regs) << DECODE_TYPE_BITS)}, \ + {.bits = (_mask)}, \ + {.bits = (_value)} + + +struct decode_table { + struct decode_header header; + union decode_item table; +}; + +#define DECODE_TABLE(_mask, _value, _table) \ + DECODE_HEADER(DECODE_TYPE_TABLE, _mask, _value, 0), \ + {.table = (_table)} + + +struct decode_custom { + struct decode_header header; + union decode_item decoder; +}; + +#define DECODE_CUSTOM(_mask, _value, _decoder) \ + DECODE_HEADER(DECODE_TYPE_CUSTOM, _mask, _value, 0), \ + {.decoder = (_decoder)} + + +struct decode_simulate { + struct decode_header header; + union decode_item handler; +}; + +#define DECODE_SIMULATEX(_mask, _value, _handler, _regs) \ + DECODE_HEADER(DECODE_TYPE_SIMULATE, _mask, _value, _regs), \ + {.handler = (_handler)} + +#define DECODE_SIMULATE(_mask, _value, _handler) \ + DECODE_SIMULATEX(_mask, _value, _handler, 0) + + +struct decode_emulate { + struct decode_header header; + union decode_item handler; +}; + +#define DECODE_EMULATEX(_mask, _value, _handler, _regs) \ + DECODE_HEADER(DECODE_TYPE_EMULATE, _mask, _value, _regs), \ + {.handler = (_handler)} + +#define DECODE_EMULATE(_mask, _value, _handler) \ + DECODE_EMULATEX(_mask, _value, _handler, 0) + + +struct decode_or { + struct decode_header header; +}; + +#define DECODE_OR(_mask, _value) \ + DECODE_HEADER(DECODE_TYPE_OR, _mask, _value, 0) + + +struct decode_reject { + struct decode_header header; +}; + +#define DECODE_REJECT(_mask, _value) \ + DECODE_HEADER(DECODE_TYPE_REJECT, _mask, _value, 0) + + +#ifdef CONFIG_THUMB2_KERNEL +extern const union decode_item kprobe_decode_thumb16_table[]; +extern const union decode_item kprobe_decode_thumb32_table[]; +#else +extern const union decode_item kprobe_decode_arm_table[]; +#endif + +extern kprobe_check_cc * const kprobe_condition_checks[16]; + + +int kprobe_decode_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi, + const union decode_item *table, bool thumb16); + +#endif |