svn commit: r326646 - head/lib/libcam

[Alan Somers]

Author: asomers
Date: Wed Dec  6 23:24:11 2017
New Revision: 326646
URL: https://svnweb.freebsd.org/changeset/base/326646

Log:
  Fix a null-pointer dereference and a tautological check in cam_get_device
  
  Reported by:	Coverity
  CID:		1017964
  MFC after:	3 weeks
  Sponsored by:	Spectra Logic Corp
  Differential Revision:	https://reviews.freebsd.org/D13184

Modified:
  head/lib/libcam/camlib.c

Modified: head/lib/libcam/camlib.c
==============================================================================
--- head/lib/libcam/camlib.c	Wed Dec  6 23:05:22 2017	(r326645)
+++ head/lib/libcam/camlib.c	Wed Dec  6 23:24:11 2017	(r326646)
@@ -30,6 +30,7 @@ __FBSDID("$FreeBSD$");
 
 #include <sys/types.h>
 #include <sys/param.h>
+#include <assert.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <stdint.h>
@@ -132,6 +133,9 @@ cam_get_device(const char *path, char *dev_name, int d
 	 * it so we don't hose the user's string.
 	 */
 	newpath = (char *)strdup(path);
+	if (newpath == NULL)
+		return (-1);
+
 	tmpstr = newpath;
 
 	/*
@@ -140,8 +144,9 @@ cam_get_device(const char *path, char *dev_name, int d
 	if (*tmpstr == '/') {
 		tmpstr2 = tmpstr;
 		tmpstr = strrchr(tmpstr2, '/');
-		if ((tmpstr != NULL) && (*tmpstr != '\0'))
-			tmpstr++;
+		/* We know that tmpstr2 contains a '/', so strrchr can't fail */
+		assert(tmpstr != NULL && *tmpstr != '\0');
+		tmpstr++;
 	}
 
 	if (*tmpstr == '\0') {