linux-kernel - Re: [PATCH 3/3] btrfs: check io_ctl_prepare_pages return in __btrfs_write_out

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <20150222145852.GB22213@localhost.localdomain>
Date:	Sun, 22 Feb 2015 22:58:53 +0800
From:	Liu Bo <bo.li.liu@...cle.com>
To:	Omar Sandoval <osandov@...ndov.com>
Cc:	Chris Mason <clm@...com>, Josef Bacik <jbacik@...com>,
	David Sterba <dsterba@...e.cz>, linux-btrfs@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH 3/3] btrfs: check io_ctl_prepare_pages return in
 __btrfs_write_out_cache

On Tue, Feb 17, 2015 at 02:51:09AM -0800, Omar Sandoval wrote:
> If io_ctl_prepare_pages fails, the pages in io_ctl.pages are not valid.
> When we try to access them later, things will blow up in various ways.
> 

Looks good.

Reviewed-by: Liu Bo <bo.li.liu@...cle.com>

> Signed-off-by: Omar Sandoval <osandov@...ndov.com>
> ---
>  fs/btrfs/free-space-cache.c | 10 ++++++----
>  1 file changed, 6 insertions(+), 4 deletions(-)
> 
> diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c
> index d6c03f7..0460632 100644
> --- a/fs/btrfs/free-space-cache.c
> +++ b/fs/btrfs/free-space-cache.c
> @@ -1114,7 +1114,7 @@ cleanup_write_cache_enospc(struct inode *inode,
>   *
>   * This function writes out a free space cache struct to disk for quick recovery
>   * on mount.  This will return 0 if it was successfull in writing the cache out,
> - * and -1 if it was not.
> + * or an errno if it was not.
>   */
>  static int __btrfs_write_out_cache(struct btrfs_root *root, struct inode *inode,
>  				   struct btrfs_free_space_ctl *ctl,
> @@ -1130,11 +1130,11 @@ static int __btrfs_write_out_cache(struct btrfs_root *root, struct inode *inode,
>  	int ret;
>  
>  	if (!i_size_read(inode))
> -		return -1;
> +		return -EIO;
>  
>  	ret = io_ctl_init(&io_ctl, inode, root, 1);
>  	if (ret)
> -		return -1;
> +		return ret;
>  
>  	if (block_group && (block_group->flags & BTRFS_BLOCK_GROUP_DATA)) {
>  		down_write(&block_group->data_rwsem);
> @@ -1151,7 +1151,9 @@ static int __btrfs_write_out_cache(struct btrfs_root *root, struct inode *inode,
>  	}
>  
>  	/* Lock all pages first so we can lock the extent safely. */
> -	io_ctl_prepare_pages(&io_ctl, inode, 0);
> +	ret = io_ctl_prepare_pages(&io_ctl, inode, 0);
> +	if (ret)
> +		goto out;
>  
>  	lock_extent_bits(&BTRFS_I(inode)->io_tree, 0, i_size_read(inode) - 1,
>  			 0, &cached_state);
> -- 
> 2.3.0
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
> the body of a message to majordomo@...r.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
Thanks,

-liubo
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/