mm/maccess.c: actually return -EFAULT from strncpy_from_unsafe

As far as I can tell, strncpy_from_unsafe never returns -EFAULT.  ret is
the result of a __copy_from_user_inatomic(), which is 0 for success and
positive (in this case necessarily 1) for access error - it is never
negative.  So we were always returning the length of the, possibly
truncated, destination string.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Rasmus Villemoes 2015-11-05 18:50:11 -08:00 committed by Linus Torvalds
parent 3acaea6804
commit 9dd861d55b
1 changed files with 1 additions and 1 deletions

View File

@ -104,5 +104,5 @@ long strncpy_from_unsafe(char *dst, const void *unsafe_addr, long count)
pagefault_enable();
set_fs(old_fs);
return ret < 0 ? ret : src - unsafe_addr;
return ret ? -EFAULT : src - unsafe_addr;
}