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author | Kees Cook <keescook@chromium.org> | 2021-06-16 14:48:19 -0700 |
---|---|---|
committer | Kees Cook <keescook@chromium.org> | 2022-02-13 16:50:06 -0800 |
commit | 938a000e3f9bead24ea753286b3e4d2423275c9e (patch) | |
tree | f3cdcabaea66b2f14b5488b6180cf552814b5aec | |
parent | f68f2ff91512c199ec24883001245912afc17873 (diff) | |
download | linux-938a000e3f9bead24ea753286b3e4d2423275c9e.tar.bz2 |
fortify: Detect struct member overflows in memmove() at compile-time
As done for memcpy(), also update memmove() to use the same tightened
compile-time checks under CONFIG_FORTIFY_SOURCE.
Signed-off-by: Kees Cook <keescook@chromium.org>
-rw-r--r-- | arch/x86/boot/compressed/misc.c | 3 | ||||
-rw-r--r-- | arch/x86/lib/memcpy_32.c | 1 | ||||
-rw-r--r-- | include/linux/fortify-string.h | 21 | ||||
-rw-r--r-- | lib/test_fortify/read_overflow2_field-memmove.c | 5 | ||||
-rw-r--r-- | lib/test_fortify/write_overflow_field-memmove.c | 5 |
5 files changed, 17 insertions, 18 deletions
diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c index a4339cb2d247..1cdcaf34ee36 100644 --- a/arch/x86/boot/compressed/misc.c +++ b/arch/x86/boot/compressed/misc.c @@ -37,10 +37,11 @@ * try to define their own functions if these are not defined as macros. */ #define memzero(s, n) memset((s), 0, (n)) +#ifndef memmove #define memmove memmove - /* Functions used by the included decompressor code below. */ void *memmove(void *dest, const void *src, size_t n); +#endif /* * This is set up by the setup-routine at boot-time diff --git a/arch/x86/lib/memcpy_32.c b/arch/x86/lib/memcpy_32.c index 3a6e6cfe8c35..ef3af7ff2c8a 100644 --- a/arch/x86/lib/memcpy_32.c +++ b/arch/x86/lib/memcpy_32.c @@ -4,6 +4,7 @@ #undef memcpy #undef memset +#undef memmove __visible void *memcpy(void *to, const void *from, size_t n) { diff --git a/include/linux/fortify-string.h b/include/linux/fortify-string.h index f578d00403ad..098d8a322a7a 100644 --- a/include/linux/fortify-string.h +++ b/include/linux/fortify-string.h @@ -309,22 +309,10 @@ __FORTIFY_INLINE void fortify_memcpy_chk(__kernel_size_t size, __builtin_object_size(p, 0), __builtin_object_size(q, 0), \ __builtin_object_size(p, 1), __builtin_object_size(q, 1), \ memcpy) - -__FORTIFY_INLINE void *memmove(void *p, const void *q, __kernel_size_t size) -{ - size_t p_size = __builtin_object_size(p, 0); - size_t q_size = __builtin_object_size(q, 0); - - if (__builtin_constant_p(size)) { - if (p_size < size) - __write_overflow(); - if (q_size < size) - __read_overflow2(); - } - if (p_size < size || q_size < size) - fortify_panic(__func__); - return __underlying_memmove(p, q, size); -} +#define memmove(p, q, s) __fortify_memcpy_chk(p, q, s, \ + __builtin_object_size(p, 0), __builtin_object_size(q, 0), \ + __builtin_object_size(p, 1), __builtin_object_size(q, 1), \ + memmove) extern void *__real_memscan(void *, int, __kernel_size_t) __RENAME(memscan); __FORTIFY_INLINE void *memscan(void *p, int c, __kernel_size_t size) @@ -413,7 +401,6 @@ __FORTIFY_INLINE char *strcpy(char *p, const char *q) /* Don't use these outside the FORITFY_SOURCE implementation */ #undef __underlying_memchr #undef __underlying_memcmp -#undef __underlying_memmove #undef __underlying_memset #undef __underlying_strcat #undef __underlying_strcpy diff --git a/lib/test_fortify/read_overflow2_field-memmove.c b/lib/test_fortify/read_overflow2_field-memmove.c new file mode 100644 index 000000000000..6cc2724c8f62 --- /dev/null +++ b/lib/test_fortify/read_overflow2_field-memmove.c @@ -0,0 +1,5 @@ +// SPDX-License-Identifier: GPL-2.0-only +#define TEST \ + memmove(large, instance.buf, sizeof(instance.buf) + 1) + +#include "test_fortify.h" diff --git a/lib/test_fortify/write_overflow_field-memmove.c b/lib/test_fortify/write_overflow_field-memmove.c new file mode 100644 index 000000000000..377fcf9bb2fd --- /dev/null +++ b/lib/test_fortify/write_overflow_field-memmove.c @@ -0,0 +1,5 @@ +// SPDX-License-Identifier: GPL-2.0-only +#define TEST \ + memmove(instance.buf, large, sizeof(instance.buf) + 1) + +#include "test_fortify.h" |