strcmp: fix overflow and possibly signedness error
Doing the strcmp return value as
signed char __res = *cs - *ct;
is wrong for two reasons. The subtraction can overflow because __res
doesn't use a type big enough. Moreover the compared bytes should be
interpreted as unsigned char as specified by POSIX.
The same problem is fixed in strncmp.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Michael Buesch <mb@bu3sch.de>
Cc: Andreas Schwab <schwab@linux-m68k.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 file changed