Re: 2.5.70-mm1 bootcrash, possibly RAID-1

[Neil Brown]

On Thursday May 29, [e-mail] wrote:
> How does the following patch look for the double free.
> 

Thanks. It is a good start, but there are other problems with freeing
things on error paths.   This patch should fix it all.

NeilBrown

--------------------------------------------
Fix up freeing of kmalloc structures

Some paths free things twice, others free un-initialised values :-(
Not any more.

 ----------- Diffstat output ------------
 ./drivers/md/raid0.c |   17 ++++++++---------
 1 files changed, 8 insertions(+), 9 deletions(-)

diff ./drivers/md/raid0.c~current~ ./drivers/md/raid0.c
--- ./drivers/md/raid0.c~current~	2003-05-30 11:40:06.000000000 +1000
+++ ./drivers/md/raid0.c	2003-05-30 11:47:03.000000000 +1000
@@ -85,10 +85,8 @@ static int create_strip_zones (mddev_t *
 	conf->devlist = kmalloc(sizeof(mdk_rdev_t*)*
 				conf->nr_strip_zones*mddev->raid_disks,
 				GFP_KERNEL);
-	if (!conf->devlist) {
-		kfree(conf);
+	if (!conf->devlist)
 		return 1;
-	}
 
 	memset(conf->strip_zone, 0,sizeof(struct strip_zone)*
 				   conf->nr_strip_zones);
@@ -235,6 +233,8 @@ static int raid0_run (mddev_t *mddev)
 		goto out;
 	mddev->private = (void *)conf;
  
+	mddev->strip_zone = NULL;
+	mddev->devlist = NULL;
 	if (create_strip_zones (mddev)) 
 		goto out_free_conf;
 
@@ -273,7 +273,7 @@ static int raid0_run (mddev_t *mddev)
 				nb_zone*sizeof(struct strip_zone*));
 	conf->hash_table = kmalloc (sizeof (struct strip_zone *)*nb_zone, GFP_KERNEL);
 	if (!conf->hash_table)
-		goto out_free_zone_conf;
+		goto out_free_conf;
 	size = conf->strip_zone[cur].size;
 
 	for (i=0; i< nb_zone; i++) {
@@ -296,12 +296,11 @@ static int raid0_run (mddev_t *mddev)
 	blk_queue_merge_bvec(&mddev->queue, raid0_mergeable_bvec);
 	return 0;
 
-out_free_zone_conf:
-	kfree(conf->strip_zone);
-	conf->strip_zone = NULL;
-
 out_free_conf:
-	kfree (conf->devlist);
+	if (conf->strip_zone)
+		kfree(conf->strip_zone);
+	if (conf->devlist)
+		kfree (conf->devlist);
 	kfree(conf);
 	mddev->private = NULL;
 out: