4.20-stable review patch. If anyone has any objections, please let me know.
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From: Hans Verkuil hverkuil-cisco@xs4all.nl
commit 701f49bc028edb19ffccd101997dd84f0d71e279 upstream.
kthread_run returns an error pointer, but elsewhere in the code dev->kthread_vid_cap/out is checked against NULL.
If kthread_run returns an error, then set the pointer to NULL.
I chose this method over changing all kthread_vid_cap/out tests elsewhere since this is more robust.
Signed-off-by: Hans Verkuil hverkuil-cisco@xs4all.nl Reported-by: syzbot+53d5b2df0d9744411e2e@syzkaller.appspotmail.com Signed-off-by: Mauro Carvalho Chehab mchehab+samsung@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/media/platform/vivid/vivid-kthread-cap.c | 5 ++++- drivers/media/platform/vivid/vivid-kthread-out.c | 5 ++++- 2 files changed, 8 insertions(+), 2 deletions(-)
--- a/drivers/media/platform/vivid/vivid-kthread-cap.c +++ b/drivers/media/platform/vivid/vivid-kthread-cap.c @@ -873,8 +873,11 @@ int vivid_start_generating_vid_cap(struc "%s-vid-cap", dev->v4l2_dev.name);
if (IS_ERR(dev->kthread_vid_cap)) { + int err = PTR_ERR(dev->kthread_vid_cap); + + dev->kthread_vid_cap = NULL; v4l2_err(&dev->v4l2_dev, "kernel_thread() failed\n"); - return PTR_ERR(dev->kthread_vid_cap); + return err; } *pstreaming = true; vivid_grab_controls(dev, true); --- a/drivers/media/platform/vivid/vivid-kthread-out.c +++ b/drivers/media/platform/vivid/vivid-kthread-out.c @@ -244,8 +244,11 @@ int vivid_start_generating_vid_out(struc "%s-vid-out", dev->v4l2_dev.name);
if (IS_ERR(dev->kthread_vid_out)) { + int err = PTR_ERR(dev->kthread_vid_out); + + dev->kthread_vid_out = NULL; v4l2_err(&dev->v4l2_dev, "kernel_thread() failed\n"); - return PTR_ERR(dev->kthread_vid_out); + return err; } *pstreaming = true; vivid_grab_controls(dev, true);