From mboxrd@z Thu Jan  1 00:00:00 1970
From: =?ISO-8859-15?Q?Luk=E1=A8_Czerner?= <lczerner@redhat.com>
Subject: Re: [PATCH] ext4: fix potential null pointer dereference in
 ext4_free_inode
Date: Tue, 8 Jul 2014 13:00:09 +0200 (CEST)
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Cc: "Theodore Ts'o" <tytso@mit.edu>,
	linux-ext4 <linux-ext4@vger.kernel.org>,
	"'Dan Carpenter'" <dan.carpenter@oracle.com>,
	Ashish Sangwan <a.sangwan@samsung.com>
To: Namjae Jeon <namjae.jeon@samsung.com>
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On Tue, 8 Jul 2014, Namjae Jeon wrote:

> Date: Tue, 08 Jul 2014 14:41:22 +0900
> From: Namjae Jeon <namjae.jeon@samsung.com>
> To: Theodore Ts'o <tytso@mit.edu>
> Cc: linux-ext4 <linux-ext4@vger.kernel.org>,
>     'Dan Carpenter' <dan.carpenter@oracle.com>,
>     Ashish Sangwan <a.sangwan@samsung.com>
> Subject: [PATCH] ext4: fix potential null pointer dereference in
>     ext4_free_inode
> 
> Fix potential null pointer dereferencing problem caused by e43bb4e612
> ("ext4: decrement free clusters/inodes counters when block group declared bad")
> 
> Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
> Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
> Signed-off-by: Ashish Sangwan <a.sangwan@samsung.com>

Looks good.

Reviewed-by: Lukas Czerner <lczerner@redhat.com>

> ---
>  fs/ext4/ialloc.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c
> index a87455d..6bfe7eb 100644
> --- a/fs/ext4/ialloc.c
> +++ b/fs/ext4/ialloc.c
> @@ -338,7 +338,7 @@ out:
>  			fatal = err;
>  	} else {
>  		ext4_error(sb, "bit already cleared for inode %lu", ino);
> -		if (!EXT4_MB_GRP_IBITMAP_CORRUPT(grp)) {
> +		if (gdp && !EXT4_MB_GRP_IBITMAP_CORRUPT(grp)) {
>  			int count;
>  			count = ext4_free_inodes_count(sb, gdp);
>  			percpu_counter_sub(&sbi->s_freeinodes_counter,
>