From: Ludwig Disterhof Date: Mon, 28 Apr 2025 18:16:50 +0000 (+0200) Subject: media: usbtv: Lock resolution while streaming X-Git-Tag: v6.12.44~218 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=c3d75524e10021aa5c223d94da4996640aed46c0;p=thirdparty%2Fkernel%2Fstable.git media: usbtv: Lock resolution while streaming commit 7e40e0bb778907b2441bff68d73c3eb6b6cd319f upstream. When an program is streaming (ffplay) and another program (qv4l2) changes the TV standard from NTSC to PAL, the kernel crashes due to trying to copy to unmapped memory. Changing from NTSC to PAL increases the resolution in the usbtv struct, but the video plane buffer isn't adjusted, so it overflows. Fixes: 0e0fe3958fdd13d ("[media] usbtv: Add support for PAL video source") Cc: stable@vger.kernel.org Signed-off-by: Ludwig Disterhof Signed-off-by: Hans Verkuil [hverkuil: call vb2_is_busy instead of vb2_is_streaming] Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/media/usb/usbtv/usbtv-video.c b/drivers/media/usb/usbtv/usbtv-video.c index 702f1c8bd2ab3..9dc882c1a7809 100644 --- a/drivers/media/usb/usbtv/usbtv-video.c +++ b/drivers/media/usb/usbtv/usbtv-video.c @@ -73,6 +73,10 @@ static int usbtv_configure_for_norm(struct usbtv *usbtv, v4l2_std_id norm) } if (params) { + if (vb2_is_busy(&usbtv->vb2q) && + (usbtv->width != params->cap_width || + usbtv->height != params->cap_height)) + return -EBUSY; usbtv->width = params->cap_width; usbtv->height = params->cap_height; usbtv->n_chunks = usbtv->width * usbtv->height