4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Hans Verkuil <hverkuil-cisco@xxxxxxxxx> 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@xxxxxxxxx> Reported-by: syzbot+53d5b2df0d9744411e2e@xxxxxxxxxxxxxxxxxxxxxxxxx Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- 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 @@ -877,8 +877,11 @@ 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 @@ -248,8 +248,11 @@ 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);