Syzbot reported a crash in video_usercopy(). It turns out when we
broke video_get_user() into a separate function then we accidentally
moved it outside the if block so it tries to memset a user pointer.
Reported-by: syzbot+9240c422be249a8422bd@xxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: c8ef1a6076bf ("media: v4l2-core: split out data copy from video_usercopy")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
---
Not actually tested. :( Sorry.
drivers/media/v4l2-core/v4l2-ioctl.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
index b68ff06009cd..aaf83e254272 100644
--- a/drivers/media/v4l2-core/v4l2-ioctl.c
+++ b/drivers/media/v4l2-core/v4l2-ioctl.c
@@ -3205,12 +3205,12 @@ video_usercopy(struct file *file, unsigned int orig_cmd, unsigned long arg,
parg = mbuf;
}
+ err = video_get_user((void __user *)arg, parg, orig_cmd,
+ &always_copy);
+ if (err)
+ goto out;
}
- err = video_get_user((void __user *)arg, parg, orig_cmd, &always_copy);
- if (err)
- goto out;
-
err = check_array_args(cmd, parg, &array_size, &user_ptr, &kernel_ptr);
if (err < 0)
goto out;
--
2.11.0
