From: Dan Rosenberg <drosenberg@vsecurity.com>
Date: Sun, 26 Dec 2010 06:54:53 +0000 (+0000)
Subject: CAN: Use inode instead of kernel address for /proc file
X-Git-Tag: v2.6.32.37~5
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=40521c939c106814166d9bc72f85e6aa5bfa868d;p=karo-tx-linux.git

CAN: Use inode instead of kernel address for /proc file

commit 9f260e0efa4766e56d0ac14f1aeea6ee5eb8fe83 upstream.

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@vsecurity.com>
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Cc: Moritz Muehlenhoff <jmm@debian.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

diff --git a/net/can/bcm.c b/net/can/bcm.c
index 4a192f7d93f8..029dcc2b323b 100644
--- a/net/can/bcm.c
+++ b/net/can/bcm.c
@@ -124,7 +124,7 @@ 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)
@@ -1519,7 +1519,7 @@ 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);