[PATCH] jbd2: deregister proc on failure in jbd2_journal_init_inode

[PATCH] jbd2: deregister proc on failure in jbd2_journal_init_inode

[Sami Liedes]

jbd2_journal_init_inode() does not call jbd2_stats_proc_exit() on all
failure paths after calling jbd2_stats_proc_init(). This leaves
dangling references to the fs in proc.

This patch fixes bug #11493.

Signed-off-by: Sami Liedes <sliedes@cc.hut.fi>

---

I hope this is correct. I don't understand the code very well, but I
did test my patch and it seems to fix the problem. Please don't hit me
too hard, this is the first kernel patch I have ever submitted.

diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
index 783de11..e70d657 100644
--- a/fs/jbd2/journal.c
+++ b/fs/jbd2/journal.c
@@ -1089,6 +1089,7 @@ journal_t * jbd2_journal_init_inode (struct inode *inode)
 	if (!journal->j_wbuf) {
 		printk(KERN_ERR "%s: Cant allocate bhs for commit thread\n",
 			__func__);
+		jbd2_stats_proc_exit(journal);
 		kfree(journal);
 		return NULL;
 	}
@@ -1098,6 +1099,7 @@ journal_t * jbd2_journal_init_inode (struct inode *inode)
 	if (err) {
 		printk(KERN_ERR "%s: Cannnot locate journal superblock\n",
 		       __func__);
+		jbd2_stats_proc_exit(journal);
 		kfree(journal);
 		return NULL;
 	}

Re: [PATCH] jbd2: deregister proc on failure in jbd2_journal_init_inode

[Theodore Tso]

On Sun, Nov 02, 2008 at 09:58:57PM +0200, Sami Liedes wrote:
> jbd2_journal_init_inode() does not call jbd2_stats_proc_exit() on all
> failure paths after calling jbd2_stats_proc_init(). This leaves
> dangling references to the fs in proc.
> 
> This patch fixes bug #11493.
> 
> Signed-off-by: Sami Liedes <sliedes@cc.hut.fi>
> 
> ---
> 
> I hope this is correct. I don't understand the code very well, but I
> did test my patch and it seems to fix the problem. Please don't hit me
> too hard, this is the first kernel patch I have ever submitted.

The patch looks good.  I'll get this into the ext4 patch queue and
queue it for submission to Linus.  I normally reference kernel bugs
via the full URL, i.e:

This patch fixes a bug reported by Sami Leides at:
http://bugzilla.kernel.org/show_bug.cgi?id=11493

...but that's just a tiny nit.   Thanks!!

							- Ted