File v4l-conf-fix-CVE-2020-13696.patch of Package xawtv.15326

From 31f31f9cbaee7be806cba38e0ff5431bd44b20a3 Mon Sep 17 00:00:00 2001
From: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Date: Sat, 16 May 2020 01:22:07 +0200
Subject: [PATCH 1/3] v4l-conf: check file type before opening it

Let's avoid open the file if it doesn't exist or it is not
a file of the right type.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
---
 console/v4l-conf.c | 17 ++++++++++-------
 1 file changed, 10 insertions(+), 7 deletions(-)

Index: xawtv-3.103/console/v4l-conf.c
===================================================================
--- xawtv-3.103.orig/console/v4l-conf.c
+++ xawtv-3.103/console/v4l-conf.c
@@ -134,20 +134,23 @@ dev_open(const char *device, int major)
 	exit(1);
     }
 
-    /* open & check v4l device */
-    if (-1 == (fd = open(device,O_RDWR))) {
-	fprintf(stderr, "can't open %s: %s\n", device, strerror(errno));
+    /* First check if the device is really a devnode of the right type */
+    if (-1 == stat(device, &stb)) {
+	fprintf(stderr, "invalid path or file is not of the right type %s\n", device);
 	exit(1);
     }
 
-    if (-1 == fstat(fd,&stb)) {
-	fprintf(stderr, "fstat(%s): %s\n", device, strerror(errno));
+    if (!S_ISCHR(stb.st_mode) || (major(stb.st_rdev) != major)) {
+	fprintf(stderr, "invalid path or file is not of the right type %s\n", device);
 	exit(1);
     }
-    if (!S_ISCHR(stb.st_mode) || (major(stb.st_rdev) != major)) {
-	fprintf(stderr, "%s: wrong device\n", device);
+
+    /* Then open it */
+    if (-1 == (fd = open(device,O_RDWR))) {
+	fprintf(stderr, "can't open %s: %s\n", device, strerror(errno));
 	exit(1);
     }
+
     return fd;
 }