This is a note to let you know that I've just added the patch titled kfifo: fix kfifo_to_user() return type to the 5.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: kfifo-fix-kfifo_to_user-return-type.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 792e786ed431c74dbacd54a6059c6c0e60c8c316 Author: Dan Carpenter <dan.carpenter@xxxxxxxxxx> Date: Fri Jun 24 08:30:04 2022 +0300 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: 144ecf310eb5 ("kfifo: fix kfifo_alloc() to return a signed int value") Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> Cc: Stefani Seibold <stefani@xxxxxxxxxxx> Cc: Randy Dunlap <randy.dunlap@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/include/linux/kfifo.h b/include/linux/kfifo.h index fc4b0b10210f..d3e0f9dc2587 100644 --- a/include/linux/kfifo.h +++ b/include/linux/kfifo.h @@ -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); \