This is a note to let you know that I've just added the patch titled
media: hdpvr: fix error value returns in hdpvr_read
to the 4.19-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:
media-hdpvr-fix-error-value-returns-in-hdpvr_read.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit a4f3d52fa02fa38b3fd759c4be7d678b3f8d8ca0
Author: Niels Dossche <dossche.niels@xxxxxxxxx>
Date: Tue Jun 14 18:50:02 2022 +0100
media: hdpvr: fix error value returns in hdpvr_read
[ 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@xxxxxxxxx>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/media/usb/hdpvr/hdpvr-video.c b/drivers/media/usb/hdpvr/hdpvr-video.c
index ce46f8721470..1fb2cdd9c4b2 100644
--- a/drivers/media/usb/hdpvr/hdpvr-video.c
+++ b/drivers/media/usb/hdpvr/hdpvr-video.c
@@ -413,7 +413,7 @@ 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)
