The fortified version of strscpy ensures the following before vanilla strscpy
is called:
1. There is no read overflow because we either size is smaller than
src length or we shrink size to src length by calling fortified
strnlen.
2. There is no write overflow because we either failed during
compilation or at runtime by checking that size is smaller than dest
size.
Link: https://lkml.kernel.org/r/20201122162451.27551-4-laniel_francis@privacyrequired.com
Signed-off-by: Francis Laniel <laniel_francis@privacyrequired.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Daniel Axtens <dja@axtens.net>
Cc: Daniel Micay <danielmicay@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
33e56a59e6