From: Niels Dossche <dossche.niels@gmail.com> stable inclusion from stable-v5.10.137 commit bb480bffc1fd439f12635302957ed932bb1a5e9f category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I60PLB Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit 359c27c6ddbde404f44a9c0d3ec88ccd1e2042f2 ] Error return values are supposed to be negative in hdpvr_read. Most error returns are currently handled via an unsigned integer "ret". When setting a negative error value to "ret", the value actually becomes a large positive value, because "ret" is unsigned. Later on, the "ret" value is returned. But as ssize_t is a 64-bit signed number, the error return value stays a large positive integer instead of a negative integer. This can cause an error value to be interpreted as the read size, which can cause a buffer overread for applications relying on the returned size. Fixes: 9aba42efe85b ("V4L/DVB (11096): V4L2 Driver for the Hauppauge HD PVR usb capture device") Signed-off-by: Niels Dossche <dossche.niels@gmail.com> Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> Reviewed-by: Wei Li <liwei391@huawei.com> --- drivers/media/usb/hdpvr/hdpvr-video.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/media/usb/hdpvr/hdpvr-video.c b/drivers/media/usb/hdpvr/hdpvr-video.c index 60e57e0f1927..fd7d2a9d0449 100644 --- a/drivers/media/usb/hdpvr/hdpvr-video.c +++ b/drivers/media/usb/hdpvr/hdpvr-video.c @@ -409,7 +409,7 @@ static ssize_t hdpvr_read(struct file *file, char __user *buffer, size_t count, struct hdpvr_device *dev = video_drvdata(file); struct hdpvr_buffer *buf = NULL; struct urb *urb; - unsigned int ret = 0; + int ret = 0; int rem, cnt; if (*pos) -- 2.20.1