linux-kernel - Re: [PATCH 2.6.23-rc1] eCryptfs: fix lookup error for special files

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>] [day] [month] [year] [list]

Message-ID: <20070801145740.GF30416@halcrow.austin.ibm.com>
Date:	Wed, 1 Aug 2007 09:57:40 -0500
From:	Michael Halcrow <mhalcrow@...ibm.com>
To:	Ryusuke Konishi <konishi.ryusuke@....ntt.co.jp>
Cc:	Andrew Morton <akpm@...ux-foundation.org>,
	ecryptfs-devel@...ts.sourceforge.net, moriai.satoshi@....ntt.co.jp,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH 2.6.23-rc1] eCryptfs: fix lookup error for special files

On Wed, Aug 01, 2007 at 10:01:14PM +0900, Ryusuke Konishi wrote:
> When ecryptfs_lookup() is called against special files, eCryptfs
> generates the following errors because it tries to treat them like
> regular eCryptfs files.
> 
> Error opening lower file for lower_dentry [0xffff810233a6f150], lower_mnt [0xffff810235bb4c80], and flags 
> [0x8000]
> Error opening lower_file to read header region
> Error attempting to read the [user.ecryptfs] xattr from the lower file; return value = [-95]
> Valid metadata not found in header region or xattr region; treating file as unencrypted
> 
> For instance, the problem can be reproduced by the steps below.
> 
>   # mkdir /root/crypt /mnt/crypt
>   # mount -t ecryptfs /root/crypt /mnt/crypt
>   # mknod /mnt/crypt/c0 c 0 0
>   # umount /mnt/crypt
>   # mount -t ecryptfs /root/crypt /mnt/crypt
>   # ls -l /mnt/crypt
> 
> This patch fixes it by adding a check similar to directories and
> symlinks.
> 
> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@....ntt.co.jp>

Acked-by: Michael Halcrow <mhalcrow@...ibm.com>

> ---
>  fs/ecryptfs/inode.c |    4 ++++
>  1 files changed, 4 insertions(+), 0 deletions(-)
> 
> diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
> index 0a50942..131954b 100644
> --- a/fs/ecryptfs/inode.c
> +++ b/fs/ecryptfs/inode.c
> @@ -353,6 +353,10 @@ static struct dentry *ecryptfs_lookup(struct inode *dir, struct dentry *dentry,
>  		ecryptfs_printk(KERN_DEBUG, "Is a symlink; returning\n");
>  		goto out;
>  	}
> +	if (special_file(lower_inode->i_mode)) {
> +		ecryptfs_printk(KERN_DEBUG, "Is a special file; returning\n");
> +		goto out;
> +	}
>  	if (!nd) {
>  		ecryptfs_printk(KERN_DEBUG, "We have a NULL nd, just leave"
>  				"as we *think* we are about to unlink\n");
-
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/