From 2e7682ebfc750177a4944eeb56e97a3f05734528 Mon Sep 17 00:00:00 2001
From: YueHaibing <yuehaibing@huawei.com>
Date: Thu, 14 Mar 2019 22:01:24 -0400
Subject: [PATCH] media: tw5864: Fix possible NULL pointer dereference in tw5864_handle_frame
Git-commit: 2e7682ebfc750177a4944eeb56e97a3f05734528
Patch-mainline: v5.2-rc1
References: CVE-2019-20806 bsc#1172199 bsc#1051510
'vb' null check should be done before dereferencing it in
tw5864_handle_frame, otherwise a NULL pointer dereference
may occur.
Fixes: 34d1324edd31 ("[media] pci: Add tw5864 driver")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/media/pci/tw5864/tw5864-video.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/media/pci/tw5864/tw5864-video.c b/drivers/media/pci/tw5864/tw5864-video.c
index 5a1f3aa4101a..434d313a3c15 100644
--- a/drivers/media/pci/tw5864/tw5864-video.c
+++ b/drivers/media/pci/tw5864/tw5864-video.c
@@ -1395,13 +1395,13 @@ static void tw5864_handle_frame(struct tw5864_h264_frame *frame)
input->vb = NULL;
spin_unlock_irqrestore(&input->slock, flags);
- v4l2_buf = to_vb2_v4l2_buffer(&vb->vb.vb2_buf);
-
if (!vb) { /* Gone because of disabling */
dev_dbg(&dev->pci->dev, "vb is empty, dropping frame\n");
return;
}
+ v4l2_buf = to_vb2_v4l2_buffer(&vb->vb.vb2_buf);
+
/*
* Check for space.
* Mind the overhead of startcode emulation prevention.
--
2.16.4