diff options
| author | Alexander Potapenko <glider@google.com> | 2024-03-20 13:18:50 +0300 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2024-04-26 07:07:02 +0300 |
| commit | 922621a6828430ea3119b869336157d253489334 (patch) | |
| tree | 02a478c708f886648d58b53dc5f6f82b7fe5d4fb | |
| parent | 3429055f0451cd3a281f8ed6691335ead626b136 (diff) | |
| download | linux-922621a6828430ea3119b869336157d253489334.tar.xz | |
instrumented.h: add instrument_memcpy_before, instrument_memcpy_after
Bug detection tools based on compiler instrumentation may miss memory
accesses in custom memcpy implementations (such as copy_mc_to_kernel).
Provide instrumentation hooks that tell KASAN, KCSAN, and KMSAN about such
accesses.
Link: https://lore.kernel.org/all/3b7dbd88-0861-4638-b2d2-911c97a4cadf@I-love.SAKURA.ne.jp/
Link: https://lkml.kernel.org/r/20240320101851.2589698-2-glider@google.com
Signed-off-by: Alexander Potapenko <glider@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| -rw-r--r-- | include/linux/instrumented.h | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/include/linux/instrumented.h b/include/linux/instrumented.h index 1b608e00290a..711a1f0d1a73 100644 --- a/include/linux/instrumented.h +++ b/include/linux/instrumented.h @@ -148,6 +148,41 @@ instrument_copy_from_user_after(const void *to, const void __user *from, } /** + * instrument_memcpy_before - add instrumentation before non-instrumented memcpy + * @to: destination address + * @from: source address + * @n: number of bytes to copy + * + * Instrument memory accesses that happen in custom memcpy implementations. The + * instrumentation should be inserted before the memcpy call. + */ +static __always_inline void instrument_memcpy_before(void *to, const void *from, + unsigned long n) +{ + kasan_check_write(to, n); + kasan_check_read(from, n); + kcsan_check_write(to, n); + kcsan_check_read(from, n); +} + +/** + * instrument_memcpy_after - add instrumentation after non-instrumented memcpy + * @to: destination address + * @from: source address + * @n: number of bytes to copy + * @left: number of bytes not copied (if known) + * + * Instrument memory accesses that happen in custom memcpy implementations. The + * instrumentation should be inserted after the memcpy call. + */ +static __always_inline void instrument_memcpy_after(void *to, const void *from, + unsigned long n, + unsigned long left) +{ + kmsan_memmove(to, from, n - left); +} + +/** * instrument_get_user() - add instrumentation to get_user()-like macros * @to: destination variable, may not be address-taken * |