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-rw-r--r--arch/x86/Kconfig.debug14
-rw-r--r--arch/x86/include/asm/alternative-asm.h10
-rw-r--r--arch/x86/include/asm/alternative.h1
-rw-r--r--arch/x86/include/asm/cmpxchg_32.h218
-rw-r--r--arch/x86/include/asm/cmpxchg_64.h234
-rw-r--r--arch/x86/include/asm/string_32.h9
-rw-r--r--arch/x86/include/asm/system.h31
-rw-r--r--arch/x86/include/asm/uaccess.h1
-rw-r--r--arch/x86/include/asm/uaccess_32.h27
-rw-r--r--arch/x86/include/asm/uaccess_64.h36
-rw-r--r--arch/x86/kernel/entry_64.S11
-rw-r--r--arch/x86/kernel/head_64.S4
-rw-r--r--arch/x86/kernel/x8664_ksyms_64.c5
-rw-r--r--arch/x86/lib/copy_user_64.S14
-rw-r--r--arch/x86/lib/usercopy_32.c10
-rw-r--r--arch/x86/mm/extable.c31
16 files changed, 302 insertions, 354 deletions
diff --git a/arch/x86/Kconfig.debug b/arch/x86/Kconfig.debug
index 7d0b681a132b..731318e5ac1d 100644
--- a/arch/x86/Kconfig.debug
+++ b/arch/x86/Kconfig.debug
@@ -296,4 +296,18 @@ config OPTIMIZE_INLINING
If unsure, say N.
+config DEBUG_STRICT_USER_COPY_CHECKS
+ bool "Strict copy size checks"
+ depends on DEBUG_KERNEL && !TRACE_BRANCH_PROFILING
+ ---help---
+ Enabling this option turns a certain set of sanity checks for user
+ copy operations into compile time failures.
+
+ The copy_from_user() etc checks are there to help test if there
+ are sufficient security checks on the length argument of
+ the copy operation, by having gcc prove that the argument is
+ within bounds.
+
+ If unsure, or if you run an older (pre 4.4) gcc, say N.
+
endmenu
diff --git a/arch/x86/include/asm/alternative-asm.h b/arch/x86/include/asm/alternative-asm.h
index e2077d343c33..b97f786a48d5 100644
--- a/arch/x86/include/asm/alternative-asm.h
+++ b/arch/x86/include/asm/alternative-asm.h
@@ -1,17 +1,13 @@
#ifdef __ASSEMBLY__
-#ifdef CONFIG_X86_32
-# define X86_ALIGN .long
-#else
-# define X86_ALIGN .quad
-#endif
+#include <asm/asm.h>
#ifdef CONFIG_SMP
.macro LOCK_PREFIX
1: lock
.section .smp_locks,"a"
- .align 4
- X86_ALIGN 1b
+ _ASM_ALIGN
+ _ASM_PTR 1b
.previous
.endm
#else
diff --git a/arch/x86/include/asm/alternative.h b/arch/x86/include/asm/alternative.h
index c240efc74e00..69b74a7b877f 100644
--- a/arch/x86/include/asm/alternative.h
+++ b/arch/x86/include/asm/alternative.h
@@ -84,6 +84,7 @@ static inline void alternatives_smp_switch(int smp) {}
" .byte " __stringify(feature) "\n" /* feature bit */ \
" .byte 662b-661b\n" /* sourcelen */ \
" .byte 664f-663f\n" /* replacementlen */ \
+ " .byte 0xff + (664f-663f) - (662b-661b)\n" /* rlen <= slen */ \
".previous\n" \
".section .altinstr_replacement, \"ax\"\n" \
"663:\n\t" newinstr "\n664:\n" /* replacement */ \
diff --git a/arch/x86/include/asm/cmpxchg_32.h b/arch/x86/include/asm/cmpxchg_32.h
index ee1931be6593..ffb9bb6b6c37 100644
--- a/arch/x86/include/asm/cmpxchg_32.h
+++ b/arch/x86/include/asm/cmpxchg_32.h
@@ -8,14 +8,50 @@
* you need to test for the feature in boot_cpu_data.
*/
-#define xchg(ptr, v) \
- ((__typeof__(*(ptr)))__xchg((unsigned long)(v), (ptr), sizeof(*(ptr))))
+extern void __xchg_wrong_size(void);
+
+/*
+ * Note: no "lock" prefix even on SMP: xchg always implies lock anyway
+ * Note 2: xchg has side effect, so that attribute volatile is necessary,
+ * but generally the primitive is invalid, *ptr is output argument. --ANK
+ */
struct __xchg_dummy {
unsigned long a[100];
};
#define __xg(x) ((struct __xchg_dummy *)(x))
+#define __xchg(x, ptr, size) \
+({ \
+ __typeof(*(ptr)) __x = (x); \
+ switch (size) { \
+ case 1: \
+ asm volatile("xchgb %b0,%1" \
+ : "=q" (__x) \
+ : "m" (*__xg(ptr)), "0" (__x) \
+ : "memory"); \
+ break; \
+ case 2: \
+ asm volatile("xchgw %w0,%1" \
+ : "=r" (__x) \
+ : "m" (*__xg(ptr)), "0" (__x) \
+ : "memory"); \
+ break; \
+ case 4: \
+ asm volatile("xchgl %0,%1" \
+ : "=r" (__x) \
+ : "m" (*__xg(ptr)), "0" (__x) \
+ : "memory"); \
+ break; \
+ default: \
+ __xchg_wrong_size(); \
+ } \
+ __x; \
+})
+
+#define xchg(ptr, v) \
+ __xchg((v), (ptr), sizeof(*ptr))
+
/*
* The semantics of XCHGCMP8B are a bit strange, this is why
* there is a loop and the loading of %%eax and %%edx has to
@@ -71,57 +107,63 @@ static inline void __set_64bit_var(unsigned long long *ptr,
(unsigned int)((value) >> 32)) \
: __set_64bit(ptr, ll_low((value)), ll_high((value))))
-/*
- * Note: no "lock" prefix even on SMP: xchg always implies lock anyway
- * Note 2: xchg has side effect, so that attribute volatile is necessary,
- * but generally the primitive is invalid, *ptr is output argument. --ANK
- */
-static inline unsigned long __xchg(unsigned long x, volatile void *ptr,
- int size)
-{
- switch (size) {
- case 1:
- asm volatile("xchgb %b0,%1"
- : "=q" (x)
- : "m" (*__xg(ptr)), "0" (x)
- : "memory");
- break;
- case 2:
- asm volatile("xchgw %w0,%1"
- : "=r" (x)
- : "m" (*__xg(ptr)), "0" (x)
- : "memory");
- break;
- case 4:
- asm volatile("xchgl %0,%1"
- : "=r" (x)
- : "m" (*__xg(ptr)), "0" (x)
- : "memory");
- break;
- }
- return x;
-}
+extern void __cmpxchg_wrong_size(void);
/*
* Atomic compare and exchange. Compare OLD with MEM, if identical,
* store NEW in MEM. Return the initial value in MEM. Success is
* indicated by comparing RETURN with OLD.
*/
+#define __raw_cmpxchg(ptr, old, new, size, lock) \
+({ \
+ __typeof__(*(ptr)) __ret; \
+ __typeof__(*(ptr)) __old = (old); \
+ __typeof__(*(ptr)) __new = (new); \
+ switch (size) { \
+ case 1: \
+ asm volatile(lock "cmpxchgb %b1,%2" \
+ : "=a"(__ret) \
+ : "q"(__new), "m"(*__xg(ptr)), "0"(__old) \
+ : "memory"); \
+ break; \
+ case 2: \
+ asm volatile(lock "cmpxchgw %w1,%2" \
+ : "=a"(__ret) \
+ : "r"(__new), "m"(*__xg(ptr)), "0"(__old) \
+ : "memory"); \
+ break; \
+ case 4: \
+ asm volatile(lock "cmpxchgl %1,%2" \
+ : "=a"(__ret) \
+ : "r"(__new), "m"(*__xg(ptr)), "0"(__old) \
+ : "memory"); \
+ break; \
+ default: \
+ __cmpxchg_wrong_size(); \
+ } \
+ __ret; \
+})
+
+#define __cmpxchg(ptr, old, new, size) \
+ __raw_cmpxchg((ptr), (old), (new), (size), LOCK_PREFIX)
+
+#define __sync_cmpxchg(ptr, old, new, size) \
+ __raw_cmpxchg((ptr), (old), (new), (size), "lock; ")
+
+#define __cmpxchg_local(ptr, old, new, size) \
+ __raw_cmpxchg((ptr), (old), (new), (size), "")
#ifdef CONFIG_X86_CMPXCHG
#define __HAVE_ARCH_CMPXCHG 1
-#define cmpxchg(ptr, o, n) \
- ((__typeof__(*(ptr)))__cmpxchg((ptr), (unsigned long)(o), \
- (unsigned long)(n), \
- sizeof(*(ptr))))
-#define sync_cmpxchg(ptr, o, n) \
- ((__typeof__(*(ptr)))__sync_cmpxchg((ptr), (unsigned long)(o), \
- (unsigned long)(n), \
- sizeof(*(ptr))))
-#define cmpxchg_local(ptr, o, n) \
- ((__typeof__(*(ptr)))__cmpxchg_local((ptr), (unsigned long)(o), \
- (unsigned long)(n), \
- sizeof(*(ptr))))
+
+#define cmpxchg(ptr, old, new) \
+ __cmpxchg((ptr), (old), (new), sizeof(*ptr))
+
+#define sync_cmpxchg(ptr, old, new) \
+ __sync_cmpxchg((ptr), (old), (new), sizeof(*ptr))
+
+#define cmpxchg_local(ptr, old, new) \
+ __cmpxchg_local((ptr), (old), (new), sizeof(*ptr))
#endif
#ifdef CONFIG_X86_CMPXCHG64
@@ -133,94 +175,6 @@ static inline unsigned long __xchg(unsigned long x, volatile void *ptr,
(unsigned long long)(n)))
#endif
-static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old,
- unsigned long new, int size)
-{
- unsigned long prev;
- switch (size) {
- case 1:
- asm volatile(LOCK_PREFIX "cmpxchgb %b1,%2"
- : "=a"(prev)
- : "q"(new), "m"(*__xg(ptr)), "0"(old)
- : "memory");
- return prev;
- case 2:
- asm volatile(LOCK_PREFIX "cmpxchgw %w1,%2"
- : "=a"(prev)
- : "r"(new), "m"(*__xg(ptr)), "0"(old)
- : "memory");
- return prev;
- case 4:
- asm volatile(LOCK_PREFIX "cmpxchgl %1,%2"
- : "=a"(prev)
- : "r"(new), "m"(*__xg(ptr)), "0"(old)
- : "memory");
- return prev;
- }
- return old;
-}
-
-/*
- * Always use locked operations when touching memory shared with a
- * hypervisor, since the system may be SMP even if the guest kernel
- * isn't.
- */
-static inline unsigned long __sync_cmpxchg(volatile void *ptr,
- unsigned long old,
- unsigned long new, int size)
-{
- unsigned long prev;
- switch (size) {
- case 1:
- asm volatile("lock; cmpxchgb %b1,%2"
- : "=a"(prev)
- : "q"(new), "m"(*__xg(ptr)), "0"(old)
- : "memory");
- return prev;
- case 2:
- asm volatile("lock; cmpxchgw %w1,%2"
- : "=a"(prev)
- : "r"(new), "m"(*__xg(ptr)), "0"(old)
- : "memory");
- return prev;
- case 4:
- asm volatile("lock; cmpxchgl %1,%2"
- : "=a"(prev)
- : "r"(new), "m"(*__xg(ptr)), "0"(old)
- : "memory");
- return prev;
- }
- return old;
-}
-
-static inline unsigned long __cmpxchg_local(volatile void *ptr,
- unsigned long old,
- unsigned long new, int size)
-{
- unsigned long prev;
- switch (size) {
- case 1:
- asm volatile("cmpxchgb %b1,%2"
- : "=a"(prev)
- : "q"(new), "m"(*__xg(ptr)), "0"(old)
- : "memory");
- return prev;
- case 2:
- asm volatile("cmpxchgw %w1,%2"
- : "=a"(prev)
- : "r"(new), "m"(*__xg(ptr)), "0"(old)
- : "memory");
- return prev;
- case 4:
- asm volatile("cmpxchgl %1,%2"
- : "=a"(prev)
- : "r"(new), "m"(*__xg(ptr)), "0"(old)
- : "memory");
- return prev;
- }
- return old;
-}
-
static inline unsigned long long __cmpxchg64(volatile void *ptr,
unsigned long long old,
unsigned long long new)
diff --git a/arch/x86/include/asm/cmpxchg_64.h b/arch/x86/include/asm/cmpxchg_64.h
index 52de72e0de8c..485ae415faec 100644
--- a/arch/x86/include/asm/cmpxchg_64.h
+++ b/arch/x86/include/asm/cmpxchg_64.h
@@ -3,9 +3,6 @@
#include <asm/alternative.h> /* Provides LOCK_PREFIX */
-#define xchg(ptr, v) ((__typeof__(*(ptr)))__xchg((unsigned long)(v), \
- (ptr), sizeof(*(ptr))))
-
#define __xg(x) ((volatile long *)(x))
static inline void set_64bit(volatile unsigned long *ptr, unsigned long val)
@@ -15,167 +12,118 @@ static inline void set_64bit(volatile unsigned long *ptr, unsigned long val)
#define _set_64bit set_64bit
+extern void __xchg_wrong_size(void);
+extern void __cmpxchg_wrong_size(void);
+
/*
* Note: no "lock" prefix even on SMP: xchg always implies lock anyway
* Note 2: xchg has side effect, so that attribute volatile is necessary,
* but generally the primitive is invalid, *ptr is output argument. --ANK
*/
-static inline unsigned long __xchg(unsigned long x, volatile void *ptr,
- int size)
-{
- switch (size) {
- case 1:
- asm volatile("xchgb %b0,%1"
- : "=q" (x)
- : "m" (*__xg(ptr)), "0" (x)
- : "memory");
- break;
- case 2:
- asm volatile("xchgw %w0,%1"
- : "=r" (x)
- : "m" (*__xg(ptr)), "0" (x)
- : "memory");
- break;
- case 4:
- asm volatile("xchgl %k0,%1"
- : "=r" (x)
- : "m" (*__xg(ptr)), "0" (x)
- : "memory");
- break;
- case 8:
- asm volatile("xchgq %0,%1"
- : "=r" (x)
- : "m" (*__xg(ptr)), "0" (x)
- : "memory");
- break;
- }
- return x;
-}
+#define __xchg(x, ptr, size) \
+({ \
+ __typeof(*(ptr)) __x = (x); \
+ switch (size) { \
+ case 1: \
+ asm volatile("xchgb %b0,%1" \
+ : "=q" (__x) \
+ : "m" (*__xg(ptr)), "0" (__x) \
+ : "memory"); \
+ break; \
+ case 2: \
+ asm volatile("xchgw %w0,%1" \
+ : "=r" (__x) \
+ : "m" (*__xg(ptr)), "0" (__x) \
+ : "memory"); \
+ break; \
+ case 4: \
+ asm volatile("xchgl %k0,%1" \
+ : "=r" (__x) \
+ : "m" (*__xg(ptr)), "0" (__x) \
+ : "memory"); \
+ break; \
+ case 8: \
+ asm volatile("xchgq %0,%1" \
+ : "=r" (__x) \
+ : "m" (*__xg(ptr)), "0" (__x) \
+ : "memory"); \
+ break; \
+ default: \
+ __xchg_wrong_size(); \
+ } \
+ __x; \
+})
+
+#define xchg(ptr, v) \
+ __xchg((v), (ptr), sizeof(*ptr))
+
+#define __HAVE_ARCH_CMPXCHG 1
/*
* Atomic compare and exchange. Compare OLD with MEM, if identical,
* store NEW in MEM. Return the initial value in MEM. Success is
* indicated by comparing RETURN with OLD.
*/
+#define __raw_cmpxchg(ptr, old, new, size, lock) \
+({ \
+ __typeof__(*(ptr)) __ret; \
+ __typeof__(*(ptr)) __old = (old); \
+ __typeof__(*(ptr)) __new = (new); \
+ switch (size) { \
+ case 1: \
+ asm volatile(lock "cmpxchgb %b1,%2" \
+ : "=a"(__ret) \
+ : "q"(__new), "m"(*__xg(ptr)), "0"(__old) \
+ : "memory"); \
+ break; \
+ case 2: \
+ asm volatile(lock "cmpxchgw %w1,%2" \
+ : "=a"(__ret) \
+ : "r"(__new), "m"(*__xg(ptr)), "0"(__old) \
+ : "memory"); \
+ break; \
+ case 4: \
+ asm volatile(lock "cmpxchgl %k1,%2" \
+ : "=a"(__ret) \
+ : "r"(__new), "m"(*__xg(ptr)), "0"(__old) \
+ : "memory"); \
+ break; \
+ case 8: \
+ asm volatile(lock "cmpxchgq %1,%2" \
+ : "=a"(__ret) \
+ : "r"(__new), "m"(*__xg(ptr)), "0"(__old) \
+ : "memory"); \
+ break; \
+ default: \
+ __cmpxchg_wrong_size(); \
+ } \
+ __ret; \
+})
-#define __HAVE_ARCH_CMPXCHG 1
+#define __cmpxchg(ptr, old, new, size) \
+ __raw_cmpxchg((ptr), (old), (new), (size), LOCK_PREFIX)
-static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old,
- unsigned long new, int size)
-{
- unsigned long prev;
- switch (size) {
- case 1:
- asm volatile(LOCK_PREFIX "cmpxchgb %b1,%2"
- : "=a"(prev)
- : "q"(new), "m"(*__xg(ptr)), "0"(old)
- : "memory");
- return prev;
- case 2:
- asm volatile(LOCK_PREFIX "cmpxchgw %w1,%2"
- : "=a"(prev)
- : "r"(new), "m"(*__xg(ptr)), "0"(old)
- : "memory");
- return prev;
- case 4:
- asm volatile(LOCK_PREFIX "cmpxchgl %k1,%2"
- : "=a"(prev)
- : "r"(new), "m"(*__xg(ptr)), "0"(old)
- : "memory");
- return prev;
- case 8:
- asm volatile(LOCK_PREFIX "cmpxchgq %1,%2"
- : "=a"(prev)
- : "r"(new), "m"(*__xg(ptr)), "0"(old)
- : "memory");
- return prev;
- }
- return old;
-}
+#define __sync_cmpxchg(ptr, old, new, size) \
+ __raw_cmpxchg((ptr), (old), (new), (size), "lock; ")
-/*
- * Always use locked operations when touching memory shared with a
- * hypervisor, since the system may be SMP even if the guest kernel
- * isn't.
- */
-static inline unsigned long __sync_cmpxchg(volatile void *ptr,
- unsigned long old,
- unsigned long new, int size)
-{
- unsigned long prev;
- switch (size) {
- case 1:
- asm volatile("lock; cmpxchgb %b1,%2"
- : "=a"(prev)
- : "q"(new), "m"(*__xg(ptr)), "0"(old)
- : "memory");
- return prev;
- case 2:
- asm volatile("lock; cmpxchgw %w1,%2"
- : "=a"(prev)
- : "r"(new), "m"(*__xg(ptr)), "0"(old)
- : "memory");
- return prev;
- case 4:
- asm volatile("lock; cmpxchgl %1,%2"
- : "=a"(prev)
- : "r"(new), "m"(*__xg(ptr)), "0"(old)
- : "memory");
- return prev;
- }
- return old;
-}
+#define __cmpxchg_local(ptr, old, new, size) \
+ __raw_cmpxchg((ptr), (old), (new), (size), "")
-static inline unsigned long __cmpxchg_local(volatile void *ptr,
- unsigned long old,
- unsigned long new, int size)
-{
- unsigned long prev;
- switch (size) {
- case 1:
- asm volatile("cmpxchgb %b1,%2"
- : "=a"(prev)
- : "q"(new), "m"(*__xg(ptr)), "0"(old)
- : "memory");
- return prev;
- case 2:
- asm volatile("cmpxchgw %w1,%2"
- : "=a"(prev)
- : "r"(new), "m"(*__xg(ptr)), "0"(old)
- : "memory");
- return prev;
- case 4:
- asm volatile("cmpxchgl %k1,%2"
- : "=a"(prev)
- : "r"(new), "m"(*__xg(ptr)), "0"(old)
- : "memory");
- return prev;
- case 8:
- asm volatile("cmpxchgq %1,%2"
- : "=a"(prev)
- : "r"(new), "m"(*__xg(ptr)), "0"(old)
- : "memory");
- return prev;
- }
- return old;
-}
+#define cmpxchg(ptr, old, new) \
+ __cmpxchg((ptr), (old), (new), sizeof(*ptr))
+
+#define sync_cmpxchg(ptr, old, new) \
+ __sync_cmpxchg((ptr), (old), (new), sizeof(*ptr))
+
+#define cmpxchg_local(ptr, old, new) \
+ __cmpxchg_local((ptr), (old), (new), sizeof(*ptr))
-#define cmpxchg(ptr, o, n) \
- ((__typeof__(*(ptr)))__cmpxchg((ptr), (unsigned long)(o), \
- (unsigned long)(n), sizeof(*(ptr))))
#define cmpxchg64(ptr, o, n) \
({ \
BUILD_BUG_ON(sizeof(*(ptr)) != 8); \
cmpxchg((ptr), (o), (n)); \
})
-#define cmpxchg_local(ptr, o, n) \
- ((__typeof__(*(ptr)))__cmpxchg_local((ptr), (unsigned long)(o), \
- (unsigned long)(n), \
- sizeof(*(ptr))))
-#define sync_cmpxchg(ptr, o, n) \
- ((__typeof__(*(ptr)))__sync_cmpxchg((ptr), (unsigned long)(o), \
- (unsigned long)(n), \
- sizeof(*(ptr))))
+
#define cmpxchg64_local(ptr, o, n) \
({ \
BUILD_BUG_ON(sizeof(*(ptr)) != 8); \
diff --git a/arch/x86/include/asm/string_32.h b/arch/x86/include/asm/string_32.h
index ae907e617181..3d3e8353ee5c 100644
--- a/arch/x86/include/asm/string_32.h
+++ b/arch/x86/include/asm/string_32.h
@@ -177,10 +177,15 @@ static inline void *__memcpy3d(void *to, const void *from, size_t len)
*/
#ifndef CONFIG_KMEMCHECK
+
+#if (__GNUC__ >= 4)
+#define memcpy(t, f, n) __builtin_memcpy(t, f, n)
+#else
#define memcpy(t, f, n) \
(__builtin_constant_p((n)) \
? __constant_memcpy((t), (f), (n)) \
: __memcpy((t), (f), (n)))
+#endif
#else
/*
* kmemcheck becomes very happy if we use the REP instructions unconditionally,
@@ -316,11 +321,15 @@ void *__constant_c_and_count_memset(void *s, unsigned long pattern,
: __memset_generic((s), (c), (count)))
#define __HAVE_ARCH_MEMSET
+#if (__GNUC__ >= 4)
+#define memset(s, c, count) __builtin_memset(s, c, count)
+#else
#define memset(s, c, count) \
(__builtin_constant_p(c) \
? __constant_c_x_memset((s), (0x01010101UL * (unsigned char)(c)), \
(count)) \
: __memset((s), (c), (count)))
+#endif
/*
* find the first occurrence of byte 'c', or 1 past the area if none
diff --git a/arch/x86/include/asm/system.h b/arch/x86/include/asm/system.h
index f08f97374892..022a84386de8 100644
--- a/arch/x86/include/asm/system.h
+++ b/arch/x86/include/asm/system.h
@@ -128,8 +128,6 @@ do { \
"movq %%rsp,%P[threadrsp](%[prev])\n\t" /* save RSP */ \
"movq %P[threadrsp](%[next]),%%rsp\n\t" /* restore RSP */ \
"call __switch_to\n\t" \
- ".globl thread_return\n" \
- "thread_return:\n\t" \
"movq "__percpu_arg([current_task])",%%rsi\n\t" \
__switch_canary \
"movq %P[thread_info](%%rsi),%%r8\n\t" \
@@ -157,19 +155,22 @@ extern void native_load_gs_index(unsigned);
* Load a segment. Fall back on loading the zero
* segment if something goes wrong..
*/
-#define loadsegment(seg, value) \
- asm volatile("\n" \
- "1:\t" \
- "movl %k0,%%" #seg "\n" \
- "2:\n" \
- ".section .fixup,\"ax\"\n" \
- "3:\t" \
- "movl %k1, %%" #seg "\n\t" \
- "jmp 2b\n" \
- ".previous\n" \
- _ASM_EXTABLE(1b,3b) \
- : :"r" (value), "r" (0) : "memory")
-
+#define loadsegment(seg, value) \
+do { \
+ unsigned short __val = (value); \
+ \
+ asm volatile(" \n" \
+ "1: movl %k0,%%" #seg " \n" \
+ \
+ ".section .fixup,\"ax\" \n" \
+ "2: xorl %k0,%k0 \n" \
+ " jmp 1b \n" \
+ ".previous \n" \
+ \
+ _ASM_EXTABLE(1b, 2b) \
+ \
+ : "+r" (__val) : : "memory"); \
+} while (0)
/*
* Save a segment register away
diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h
index d2c6c930b491..abd3e0ea762a 100644
--- a/arch/x86/include/asm/uaccess.h
+++ b/arch/x86/include/asm/uaccess.h
@@ -570,7 +570,6 @@ extern struct movsl_mask {
#ifdef CONFIG_X86_32
# include "uaccess_32.h"
#else
-# define ARCH_HAS_SEARCH_EXTABLE
# include "uaccess_64.h"
#endif
diff --git a/arch/x86/include/asm/uaccess_32.h b/arch/x86/include/asm/uaccess_32.h
index 632fb44b4cb5..0c9825e97f36 100644
--- a/arch/x86/include/asm/uaccess_32.h
+++ b/arch/x86/include/asm/uaccess_32.h
@@ -187,9 +187,34 @@ __copy_from_user_inatomic_nocache(void *to, const void __user *from,
unsigned long __must_check copy_to_user(void __user *to,
const void *from, unsigned long n);
-unsigned long __must_check copy_from_user(void *to,
+unsigned long __must_check _copy_from_user(void *to,
const void __user *from,
unsigned long n);
+
+
+extern void copy_from_user_overflow(void)
+#ifdef CONFIG_DEBUG_STRICT_USER_COPY_CHECKS
+ __compiletime_error("copy_from_user() buffer size is not provably correct")
+#else
+ __compiletime_warning("copy_from_user() buffer size is not provably correct")
+#endif
+;
+
+static inline unsigned long __must_check copy_from_user(void *to,
+ const void __user *from,
+ unsigned long n)
+{
+ int sz = __compiletime_object_size(to);
+ int ret = -EFAULT;
+
+ if (likely(sz == -1 || sz >= n))
+ ret = _copy_from_user(to, from, n);
+ else
+ copy_from_user_overflow();
+
+ return ret;
+}
+
long __must_check strncpy_from_user(char *dst, const char __user *src,
long count);
long __must_check __strncpy_from_user(char *dst,
diff --git a/arch/x86/include/asm/uaccess_64.h b/arch/x86/include/asm/uaccess_64.h
index db24b215fc50..46324c6a4f6e 100644
--- a/arch/x86/include/asm/uaccess_64.h
+++ b/arch/x86/include/asm/uaccess_64.h
@@ -19,12 +19,37 @@ __must_check unsigned long
copy_user_generic(void *to, const void *from, unsigned len);
__must_check unsigned long
-copy_to_user(void __user *to, const void *from, unsigned len);
+_copy_to_user(void __user *to, const void *from, unsigned len);
__must_check unsigned long
-copy_from_user(void *to, const void __user *from, unsigned len);
+_copy_from_user(void *to, const void __user *from, unsigned len);
__must_check unsigned long
copy_in_user(void __user *to, const void __user *from, unsigned len);
+static inline unsigned long __must_check copy_from_user(void *to,
+ const void __user *from,
+ unsigned long n)
+{
+ int sz = __compiletime_object_size(to);
+ int ret = -EFAULT;
+
+ might_fault();
+ if (likely(sz == -1 || sz >= n))
+ ret = _copy_from_user(to, from, n);
+#ifdef CONFIG_DEBUG_VM
+ else
+ WARN(1, "Buffer overflow detected!\n");
+#endif
+ return ret;
+}
+
+static __always_inline __must_check
+int copy_to_user(void __user *dst, const void *src, unsigned size)
+{
+ might_fault();
+
+ return _copy_to_user(dst, src, size);
+}
+
static __always_inline __must_check
int __copy_from_user(void *dst, const void __user *src, unsigned size)
{
@@ -176,8 +201,11 @@ __must_check long strlen_user(const char __user *str);
__must_check unsigned long clear_user(void __user *mem, unsigned long len);
__must_check unsigned long __clear_user(void __user *mem, unsigned long len);
-__must_check long __copy_from_user_inatomic(void *dst, const void __user *src,
- unsigned size);
+static __must_check __always_inline int
+__copy_from_user_inatomic(void *dst, const void __user *src, unsigned size)
+{
+ return copy_user_generic(dst, (__force const void *)src, size);
+}
static __must_check __always_inline int
__copy_to_user_inatomic(void __user *dst, const void *src, unsigned size)
diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S
index 722df1b1152d..4deb8fc849dd 100644
--- a/arch/x86/kernel/entry_64.S
+++ b/arch/x86/kernel/entry_64.S
@@ -1499,12 +1499,17 @@ error_kernelspace:
leaq irq_return(%rip),%rcx
cmpq %rcx,RIP+8(%rsp)
je error_swapgs
- movl %ecx,%ecx /* zero extend */
- cmpq %rcx,RIP+8(%rsp)
- je error_swapgs
+ movl %ecx,%eax /* zero extend */
+ cmpq %rax,RIP+8(%rsp)
+ je bstep_iret
cmpq $gs_change,RIP+8(%rsp)
je error_swapgs
jmp error_sti
+
+bstep_iret:
+ /* Fix truncated RIP */
+ movq %rcx,RIP+8(%rsp)
+ jmp error_swapgs
END(error_entry)
diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S
index 780cd928fcd5..22db86a37643 100644
--- a/arch/x86/kernel/head_64.S
+++ b/arch/x86/kernel/head_64.S
@@ -212,8 +212,8 @@ ENTRY(secondary_startup_64)
*/
lgdt early_gdt_descr(%rip)
- /* set up data segments. actually 0 would do too */
- movl $__KERNEL_DS,%eax
+ /* set up data segments */
+ xorl %eax,%eax
movl %eax,%ds
movl %eax,%ss
movl %eax,%es
diff --git a/arch/x86/kernel/x8664_ksyms_64.c b/arch/x86/kernel/x8664_ksyms_64.c
index 3909e3ba5ce3..a1029769b6f2 100644
--- a/arch/x86/kernel/x8664_ksyms_64.c
+++ b/arch/x86/kernel/x8664_ksyms_64.c
@@ -30,9 +30,8 @@ EXPORT_SYMBOL(__put_user_8);
EXPORT_SYMBOL(copy_user_generic);
EXPORT_SYMBOL(__copy_user_nocache);
-EXPORT_SYMBOL(copy_from_user);
-EXPORT_SYMBOL(copy_to_user);
-EXPORT_SYMBOL(__copy_from_user_inatomic);
+EXPORT_SYMBOL(_copy_from_user);
+EXPORT_SYMBOL(_copy_to_user);
EXPORT_SYMBOL(copy_page);
EXPORT_SYMBOL(clear_page);
diff --git a/arch/x86/lib/copy_user_64.S b/arch/x86/lib/copy_user_64.S
index 6ba0f7bb85ea..cf889d4e076a 100644
--- a/arch/x86/lib/copy_user_64.S
+++ b/arch/x86/lib/copy_user_64.S
@@ -65,7 +65,7 @@
.endm
/* Standard copy_to_user with segment limit checking */
-ENTRY(copy_to_user)
+ENTRY(_copy_to_user)
CFI_STARTPROC
GET_THREAD_INFO(%rax)
movq %rdi,%rcx
@@ -75,10 +75,10 @@ ENTRY(copy_to_user)
jae bad_to_user
ALTERNATIVE_JUMP X86_FEATURE_REP_GOOD,copy_user_generic_unrolled,copy_user_generic_string
CFI_ENDPROC
-ENDPROC(copy_to_user)
+ENDPROC(_copy_to_user)
/* Standard copy_from_user with segment limit checking */
-ENTRY(copy_from_user)
+ENTRY(_copy_from_user)
CFI_STARTPROC
GET_THREAD_INFO(%rax)
movq %rsi,%rcx
@@ -88,7 +88,7 @@ ENTRY(copy_from_user)
jae bad_from_user
ALTERNATIVE_JUMP X86_FEATURE_REP_GOOD,copy_user_generic_unrolled,copy_user_generic_string
CFI_ENDPROC
-ENDPROC(copy_from_user)
+ENDPROC(_copy_from_user)
ENTRY(copy_user_generic)
CFI_STARTPROC
@@ -96,12 +96,6 @@ ENTRY(copy_user_generic)
CFI_ENDPROC
ENDPROC(copy_user_generic)
-ENTRY(__copy_from_user_inatomic)
- CFI_STARTPROC
- ALTERNATIVE_JUMP X86_FEATURE_REP_GOOD,copy_user_generic_unrolled,copy_user_generic_string
- CFI_ENDPROC
-ENDPROC(__copy_from_user_inatomic)
-
.section .fixup,"ax"
/* must zero dest */
ENTRY(bad_from_user)
diff --git a/arch/x86/lib/usercopy_32.c b/arch/x86/lib/usercopy_32.c
index 1f118d462acc..e218d5df85ff 100644
--- a/arch/x86/lib/usercopy_32.c
+++ b/arch/x86/lib/usercopy_32.c
@@ -874,7 +874,7 @@ EXPORT_SYMBOL(copy_to_user);
* data to the requested size using zero bytes.
*/
unsigned long
-copy_from_user(void *to, const void __user *from, unsigned long n)
+_copy_from_user(void *to, const void __user *from, unsigned long n)
{
if (access_ok(VERIFY_READ, from, n))
n = __copy_from_user(to, from, n);
@@ -882,4 +882,10 @@ copy_from_user(void *to, const void __user *from, unsigned long n)
memset(to, 0, n);
return n;
}
-EXPORT_SYMBOL(copy_from_user);
+EXPORT_SYMBOL(_copy_from_user);
+
+void copy_from_user_overflow(void)
+{
+ WARN(1, "Buffer overflow detected!\n");
+}
+EXPORT_SYMBOL(copy_from_user_overflow);
diff --git a/arch/x86/mm/extable.c b/arch/x86/mm/extable.c
index 61b41ca3b5a2..d0474ad2a6e5 100644
--- a/arch/x86/mm/extable.c
+++ b/arch/x86/mm/extable.c
@@ -35,34 +35,3 @@ int fixup_exception(struct pt_regs *regs)
return 0;
}
-
-#ifdef CONFIG_X86_64
-/*
- * Need to defined our own search_extable on X86_64 to work around
- * a B stepping K8 bug.
- */
-const struct exception_table_entry *
-search_extable(const struct exception_table_entry *first,
- const struct exception_table_entry *last,
- unsigned long value)
-{
- /* B stepping K8 bug */
- if ((value >> 32) == 0)
- value |= 0xffffffffUL << 32;
-
- while (first <= last) {
- const struct exception_table_entry *mid;
- long diff;
-
- mid = (last - first) / 2 + first;
- diff = mid->insn - value;
- if (diff == 0)
- return mid;
- else if (diff < 0)
- first = mid+1;
- else
- last = mid-1;
- }
- return NULL;
-}
-#endif
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-17 18:41:06 +0000