V4L/DVB (6581): Fix: avoids negative vma usage count
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
diff --git a/drivers/media/video/em28xx/em28xx-video.c b/drivers/media/video/em28xx/em28xx-video.c
index d3dd6a0..0906bc5 100644
--- a/drivers/media/video/em28xx/em28xx-video.c
+++ b/drivers/media/video/em28xx/em28xx-video.c
@@ -571,7 +571,9 @@
{
/* NOTE: buffers are not freed here */
struct em28xx_frame_t *f = vma->vm_private_data;
- f->vma_use_count--;
+
+ if (f->vma_use_count)
+ f->vma_use_count--;
}
static struct vm_operations_struct em28xx_vm_ops = {