Commit b45bcdf6 authored Jun 24, 2022 by Dan Carpenter Committed by Greg Kroah-Hartman Aug 25, 2022

kfifo: fix kfifo_to_user() return type

[ Upstream commit 045ed31e23aea840648c290dbde04797064960db ]

The kfifo_to_user() macro is supposed to return zero for success or
negative error codes.  Unfortunately, there is a signedness bug so it
returns unsigned int.  This only affects callers which try to save the
result in ssize_t and as far as I can see the only place which does that
is line6_hwdep_read().

TL;DR: s/_uint/_int/.

Link: https://lkml.kernel.org/r/YrVL3OJVLlNhIMFs@kili


Fixes: 144ecf31 ("kfifo: fix kfifo_alloc() to return a signed int value")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Stefani Seibold <stefani@seibold.net>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

parent 8ee5d40a

include/linux/kfifo.h

+1 −1

Original line number	Diff line number	Diff line
		@@ -615,7 +615,7 @@ __kfifo_uint_must_check_helper( \
		* writer, you don't need extra locking to use these macro.
		*/
		#define kfifo_to_user(fifo, to, len, copied) \
		__kfifo_uint_must_check_helper( \
		__kfifo_int_must_check_helper( \
		({ \
		typeof((fifo) + 1) __tmp = (fifo); \
		void __user *__to = (to); \