diff options
Diffstat (limited to 'arch/powerpc/kernel/ptrace.c')
-rw-r--r-- | arch/powerpc/kernel/ptrace.c | 120 |
1 files changed, 89 insertions, 31 deletions
diff --git a/arch/powerpc/kernel/ptrace.c b/arch/powerpc/kernel/ptrace.c index 8feb93e7890c..6b66cd85b433 100644 --- a/arch/powerpc/kernel/ptrace.c +++ b/arch/powerpc/kernel/ptrace.c @@ -22,6 +22,7 @@ #include <linux/errno.h> #include <linux/ptrace.h> #include <linux/regset.h> +#include <linux/tracehook.h> #include <linux/elf.h> #include <linux/user.h> #include <linux/security.h> @@ -703,7 +704,7 @@ void user_enable_single_step(struct task_struct *task) if (regs != NULL) { #if defined(CONFIG_40x) || defined(CONFIG_BOOKE) - task->thread.dbcr0 = DBCR0_IDM | DBCR0_IC; + task->thread.dbcr0 |= DBCR0_IDM | DBCR0_IC; regs->msr |= MSR_DE; #else regs->msr |= MSR_SE; @@ -716,9 +717,16 @@ void user_disable_single_step(struct task_struct *task) { struct pt_regs *regs = task->thread.regs; + +#if defined(CONFIG_BOOKE) + /* If DAC then do not single step, skip */ + if (task->thread.dabr) + return; +#endif + if (regs != NULL) { #if defined(CONFIG_40x) || defined(CONFIG_BOOKE) - task->thread.dbcr0 = 0; + task->thread.dbcr0 &= ~(DBCR0_IC | DBCR0_IDM); regs->msr &= ~MSR_DE; #else regs->msr &= ~MSR_SE; @@ -727,22 +735,76 @@ void user_disable_single_step(struct task_struct *task) clear_tsk_thread_flag(task, TIF_SINGLESTEP); } -static int ptrace_set_debugreg(struct task_struct *task, unsigned long addr, +int ptrace_set_debugreg(struct task_struct *task, unsigned long addr, unsigned long data) { - /* We only support one DABR and no IABRS at the moment */ + /* For ppc64 we support one DABR and no IABR's at the moment (ppc64). + * For embedded processors we support one DAC and no IAC's at the + * moment. + */ if (addr > 0) return -EINVAL; - /* The bottom 3 bits are flags */ + /* The bottom 3 bits in dabr are flags */ if ((data & ~0x7UL) >= TASK_SIZE) return -EIO; - /* Ensure translation is on */ +#ifndef CONFIG_BOOKE + + /* For processors using DABR (i.e. 970), the bottom 3 bits are flags. + * It was assumed, on previous implementations, that 3 bits were + * passed together with the data address, fitting the design of the + * DABR register, as follows: + * + * bit 0: Read flag + * bit 1: Write flag + * bit 2: Breakpoint translation + * + * Thus, we use them here as so. + */ + + /* Ensure breakpoint translation bit is set */ if (data && !(data & DABR_TRANSLATION)) return -EIO; + /* Move contents to the DABR register */ task->thread.dabr = data; + +#endif +#if defined(CONFIG_BOOKE) + + /* As described above, it was assumed 3 bits were passed with the data + * address, but we will assume only the mode bits will be passed + * as to not cause alignment restrictions for DAC-based processors. + */ + + /* DAC's hold the whole address without any mode flags */ + task->thread.dabr = data & ~0x3UL; + + if (task->thread.dabr == 0) { + task->thread.dbcr0 &= ~(DBSR_DAC1R | DBSR_DAC1W | DBCR0_IDM); + task->thread.regs->msr &= ~MSR_DE; + return 0; + } + + /* Read or Write bits must be set */ + + if (!(data & 0x3UL)) + return -EINVAL; + + /* Set the Internal Debugging flag (IDM bit 1) for the DBCR0 + register */ + task->thread.dbcr0 = DBCR0_IDM; + + /* Check for write and read flags and set DBCR0 + accordingly */ + if (data & 0x1UL) + task->thread.dbcr0 |= DBSR_DAC1R; + if (data & 0x2UL) + task->thread.dbcr0 |= DBSR_DAC1W; + + task->thread.regs->msr |= MSR_DE; +#endif return 0; } @@ -953,31 +1015,24 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data) return ret; } -static void do_syscall_trace(void) +/* + * We must return the syscall number to actually look up in the table. + * This can be -1L to skip running any syscall at all. + */ +long do_syscall_trace_enter(struct pt_regs *regs) { - /* the 0x80 provides a way for the tracing parent to distinguish - between a syscall stop and SIGTRAP delivery */ - ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD) - ? 0x80 : 0)); - - /* - * this isn't the same as continuing with a signal, but it will do - * for normal use. strace only continues with a signal if the - * stopping signal is not SIGTRAP. -brl - */ - if (current->exit_code) { - send_sig(current->exit_code, current, 1); - current->exit_code = 0; - } -} + long ret = 0; -void do_syscall_trace_enter(struct pt_regs *regs) -{ secure_computing(regs->gpr[0]); - if (test_thread_flag(TIF_SYSCALL_TRACE) - && (current->ptrace & PT_PTRACED)) - do_syscall_trace(); + if (test_thread_flag(TIF_SYSCALL_TRACE) && + tracehook_report_syscall_entry(regs)) + /* + * Tracing decided this syscall should not happen. + * We'll return a bogus call number to get an ENOSYS + * error, but leave the original number in regs->gpr[0]. + */ + ret = -1L; if (unlikely(current->audit_context)) { #ifdef CONFIG_PPC64 @@ -995,16 +1050,19 @@ void do_syscall_trace_enter(struct pt_regs *regs) regs->gpr[5] & 0xffffffff, regs->gpr[6] & 0xffffffff); } + + return ret ?: regs->gpr[0]; } void do_syscall_trace_leave(struct pt_regs *regs) { + int step; + if (unlikely(current->audit_context)) audit_syscall_exit((regs->ccr&0x10000000)?AUDITSC_FAILURE:AUDITSC_SUCCESS, regs->result); - if ((test_thread_flag(TIF_SYSCALL_TRACE) - || test_thread_flag(TIF_SINGLESTEP)) - && (current->ptrace & PT_PTRACED)) - do_syscall_trace(); + step = test_thread_flag(TIF_SINGLESTEP); + if (step || test_thread_flag(TIF_SYSCALL_TRACE)) + tracehook_report_syscall_exit(regs, step); } |