kernel/linux.git/lib/strscpy_kunit.c, branch v6.6.132Linux kernel stable tree (mirror)https://git.radix-linux.su/kernel/linux.git/atom?h=v6.6.1322022-11-01T17:04:52+00:00fortify: Short-circuit known-safe calls to strscpy()2022-11-01T17:04:52+00:00Kees Cookkeescook@chromium.org2022-10-02T16:17:03+00:00urn:sha1:62e1cbfc5d795381a0f237ae7ee229a92d51cf9e
Replacing compile-time safe calls of strcpy()-related functions with
strscpy() was always calling the full strscpy() logic when a builtin
would be better. For example:
char buf[16];
strcpy(buf, "yes");
would reduce to __builtin_memcpy(buf, "yes", 4), but not if it was:
strscpy(buf, yes, sizeof(buf));
Fix this by checking if all sizes are known at compile-time.
Cc: linux-hardening@vger.kernel.org
Tested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
string: Convert strscpy() self-test to KUnit2022-11-01T17:04:52+00:00Kees Cookkeescook@chromium.org2022-10-02T16:51:46+00:00urn:sha1:41eefc46a3a4682976afb5f8c4b9734ed6bfd406
Convert the strscpy() self-test to a KUnit test.
Cc: David Gow <davidgow@google.com>
Cc: Tobin C. Harding <tobin@kernel.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/lkml/Y072ZMk/hNkfwqMv@dev-arch.thelio-3990X
Signed-off-by: Kees Cook <keescook@chromium.org>