From: Theodore Ts'o <tytso@mit.edu>
Date: Sun, 13 Jul 2008 23:10:10 +0000 (-0400)
Subject: libblkid: Make sure we never reference a null dev->bid_type
X-Git-Tag: v1.41.1~127
X-Git-Url: https://git.whamcloud.com/?a=commitdiff_plain;h=bb47c2a4aff6ec6b9be7f30cd04cf7c858a84de4;p=tools%2Fe2fsprogs.git

libblkid: Make sure we never reference a null dev->bid_type

There were a few places where we don't check to make sure
dev->bid_type is non-NULL before dereferencing the pointer, mostly in
debug code.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
---

diff --git a/lib/blkid/dev.c b/lib/blkid/dev.c
index 770632b..5252a8e 100644
--- a/lib/blkid/dev.c
+++ b/lib/blkid/dev.c
@@ -34,7 +34,8 @@ void blkid_free_dev(blkid_dev dev)
 		return;
 
 	DBG(DEBUG_DEV,
-	    printf("  freeing dev %s (%s)\n", dev->bid_name, dev->bid_type));
+	    printf("  freeing dev %s (%s)\n", dev->bid_name, dev->bid_type ?
+		   dev->bid_type : "(null)"));
 	DBG(DEBUG_DEV, blkid_debug_dump_dev(dev));
 
 	list_del(&dev->bid_devs);
diff --git a/lib/blkid/devname.c b/lib/blkid/devname.c
index df96859..65c6cca 100644
--- a/lib/blkid/devname.c
+++ b/lib/blkid/devname.c
@@ -96,7 +96,8 @@ blkid_dev blkid_get_dev(blkid_cache cache, const char *devname, int flags)
 			dev2 = list_entry(p, struct blkid_struct_dev, bid_devs);
 			if (dev2->bid_flags & BLKID_BID_FL_VERIFIED)
 				continue;
-			if (strcmp(dev->bid_type, dev2->bid_type))
+			if (!dev->bid_type || !dev2->bid_type ||
+			    strcmp(dev->bid_type, dev2->bid_type))
 				continue;
 			if (dev->bid_label && dev2->bid_label &&
 			    strcmp(dev->bid_label, dev2->bid_label))
diff --git a/lib/blkid/save.c b/lib/blkid/save.c
index 76f2f9e..60aa6ce 100644
--- a/lib/blkid/save.c
+++ b/lib/blkid/save.c
@@ -34,7 +34,8 @@ static int save_dev(blkid_dev dev, FILE *file)
 		return 0;
 
 	DBG(DEBUG_SAVE,
-	    printf("device %s, type %s\n", dev->bid_name, dev->bid_type));
+	    printf("device %s, type %s\n", dev->bid_name, dev->bid_type ?
+		   dev->bid_type : "(null)"));
 
 	fprintf(file,
 		"<device DEVNO=\"0x%04lx\" TIME=\"%ld\"",