From: Miloslav Trmac <mitr@redhat.com>
Date: Thu, 19 Mar 2009 13:52:47 +0000 (-0400)
Subject: audit: ignore terminating NUL in AUDIT_USER_TTY messages
X-Git-Url: http://pilppa.com/gitweb/?a=commitdiff_plain;h=55ad2f8d340678397de5916b9cd960f17ebd7150;p=linux-2.6-omap-h63xx.git

audit: ignore terminating NUL in AUDIT_USER_TTY messages

AUDIT_USER_TTY, like all other messages sent from user-space, is sent
NUL-terminated.  Unlike other user-space audit messages, which come only
from trusted sources, AUDIT_USER_TTY messages are processed using
audit_log_n_untrustedstring().

This patch modifies AUDIT_USER_TTY handling to ignore the trailing NUL
and use the "quoted_string" representation of the message if possible.

Signed-off-by: Miloslav Trmac <mitr@redhat.com>
Cc: Eric Paris <eparis@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Steve Grubb <sgrubb@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---

diff --git a/kernel/audit.c b/kernel/audit.c
index fa3805516df..5560390cb0f 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -766,6 +766,9 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 
 				audit_log_format(ab, " msg=");
 				size = nlmsg_len(nlh);
+				if (size > 0 &&
+				    ((unsigned char *)data)[size - 1] == '\0')
+					size--;
 				audit_log_n_untrustedstring(ab, data, size);
 			}
 			audit_set_pid(ab, pid);