From: Rajeshwar R Shinde coolrrsh@gmail.com

stable inclusion from stable-v4.19.300 commit 2eee8edfff90e22980a6b22079d238c3c9d323bb bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9R4M7 CVE: CVE-2023-52764

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...

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[ Upstream commit 099be1822d1f095433f4b08af9cc9d6308ec1953 ]

Syzkaller reported the following issue: UBSAN: shift-out-of-bounds in drivers/media/usb/gspca/cpia1.c:1031:27 shift exponent 245 is too large for 32-bit type 'int'

When the value of the variable "sd->params.exposure.gain" exceeds the number of bits in an integer, a shift-out-of-bounds error is reported. It is triggered because the variable "currentexp" cannot be left-shifted by more than the number of bits in an integer. In order to avoid invalid range during left-shift, the conditional expression is added.

Reported-by: syzbot+e27f3dbdab04e43b9f73@syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/20230818164522.12806-1-coolrrsh@gmail.com Link: https://syzkaller.appspot.com/bug?extid=e27f3dbdab04e43b9f73 Signed-off-by: Rajeshwar R Shinde coolrrsh@gmail.com Signed-off-by: Hans Verkuil hverkuil-cisco@xs4all.nl Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Felix Fu fuzhen5@huawei.com --- drivers/media/usb/gspca/cpia1.c | 3 +++ 1 file changed, 3 insertions(+)

diff --git a/drivers/media/usb/gspca/cpia1.c b/drivers/media/usb/gspca/cpia1.c index 2b09af8865f4..5e785343528c 100644 --- a/drivers/media/usb/gspca/cpia1.c +++ b/drivers/media/usb/gspca/cpia1.c @@ -28,6 +28,7 @@

#include <linux/input.h> #include <linux/sched/signal.h> +#include <linux/bitops.h>

#include "gspca.h"

@@ -1033,6 +1034,8 @@ static int set_flicker(struct gspca_dev *gspca_dev, int on, int apply) sd->params.exposure.expMode = 2; sd->exposure_status = EXPOSURE_NORMAL; } + if (sd->params.exposure.gain >= BITS_PER_TYPE(currentexp)) + return -EINVAL; currentexp = currentexp << sd->params.exposure.gain; sd->params.exposure.gain = 0; /* round down current exposure to nearest value */