[CVE-2010-4565 Maverick] CAN: Use inode instead of kernel address for /proc file, CVE-2010-4565

[Brad Figg]

On 04/18/2011 01:52 PM, Leann Ogasawara wrote:
> The following changes since commit edf1830290f88fb7c7c8baebd1fa7c49e8c522c4:
>    Mel Gorman (1):
>          UBUNTU: (pre-stable) mm: page allocator: adjust the per-cpu counter threshold when memory is low
>
> are available in the git repository at:
>
>    git://kernel.ubuntu.com/ogasawara/ubuntu-maverick.git CVE-2010-4565
>
> Dan Rosenberg (1):
>        CAN: Use inode instead of kernel address for /proc file, CVE-2010-4565
>
>   net/can/bcm.c |    4 ++--
>   1 files changed, 2 insertions(+), 2 deletions(-)
>
>  From 3e9b5670cda97a3a3d6810f3095ff8d2430e0b85 Mon Sep 17 00:00:00 2001
> From: Dan Rosenberg<drosenberg at vsecurity.com>
> Date: Sun, 26 Dec 2010 06:54:53 +0000
> Subject: [PATCH] CAN: Use inode instead of kernel address for /proc file, CVE-2010-4565
>
> BugLink: http://bugs.launchpad.net/bugs/765007
>
> CVE-2010-4565
>
> Since the socket address is just being used as a unique identifier, its
> inode number is an alternative that does not leak potentially sensitive
> information.
>
> CC-ing stable because MITRE has assigned CVE-2010-4565 to the issue.
>
> Signed-off-by: Dan Rosenberg<drosenberg at vsecurity.com>
> Acked-by: Oliver Hartkopp<socketcan at hartkopp.net>
> Signed-off-by: David S. Miller<davem at davemloft.net>
> (cherry picked from commit 9f260e0efa4766e56d0ac14f1aeea6ee5eb8fe83)
>
> Signed-off-by: Leann Ogasawara<leann.ogasawara at canonical.com>
> ---
>   net/can/bcm.c |    4 ++--
>   1 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/net/can/bcm.c b/net/can/bcm.c
> index 6faa825..9d5e8ac 100644
> --- a/net/can/bcm.c
> +++ b/net/can/bcm.c
> @@ -125,7 +125,7 @@ struct bcm_sock {
>   	struct list_head tx_ops;
>   	unsigned long dropped_usr_msgs;
>   	struct proc_dir_entry *bcm_proc_read;
> -	char procname [20]; /* pointer printed in ASCII with \0 */
> +	char procname [32]; /* inode number in decimal with \0 */
>   };
>
>   static inline struct bcm_sock *bcm_sk(const struct sock *sk)
> @@ -1521,7 +1521,7 @@ static int bcm_connect(struct socket *sock, struct sockaddr *uaddr, int len,
>
>   	if (proc_dir) {
>   		/* unique socket address as filename */
> -		sprintf(bo->procname, "%p", sock);
> +		sprintf(bo->procname, "%lu", sock_i_ino(sk));
>   		bo->bcm_proc_read = proc_create_data(bo->procname, 0644,
>   						     proc_dir,
>   						&bcm_proc_fops, sk);

Seems clean enough.

Acked-by: Brad Figg <brad.figg at canonical.com>

-- 
Brad Figg brad.figg at canonical.com http://www.canonical.com