Hello Aaron Durbin, Yu-Ping Wu,
I'd like you to do a code review. Please visit
https://review.coreboot.org/c/coreboot/+/44691
to review the following change.
Change subject: libpayload: memmove: Don't make expectations of architecture memcpy ......................................................................
libpayload: memmove: Don't make expectations of architecture memcpy
default_memmove() calls memcpy() when (src > dst). This is safe for the default_memcpy() implementation, but just calling memcpy() may invoke an architecture-specific implementation. Architectures are free to implement memcpy() however they want and may assume that buffers don't overlap in either direction. So while this happens to work for all current architecture implementations of memcpy(), it's safer not to rely on that and only rely on the known implementation of default_memcpy() for the forwards-overlapping case.
Signed-off-by: Julius Werner jwerner@chromium.org Change-Id: I7ece4ce9e6622a36612bfade3deb62f351877789 --- M payloads/libpayload/libc/memory.c 1 file changed, 1 insertion(+), 1 deletion(-)
git pull ssh://review.coreboot.org:29418/coreboot refs/changes/91/44691/1
diff --git a/payloads/libpayload/libc/memory.c b/payloads/libpayload/libc/memory.c index daa53f1..cc33eab 100644 --- a/payloads/libpayload/libc/memory.c +++ b/payloads/libpayload/libc/memory.c @@ -90,7 +90,7 @@ ssize_t i;
if (src > dst) - return memcpy(dst, src, n); + return default_memcpy(dst, src, n);
if (!IS_ALIGNED((uintptr_t)dst, sizeof(unsigned long)) || !IS_ALIGNED((uintptr_t)src, sizeof(unsigned long))) {