Add patch to fix XFS memory corruption (rhbz 749166)

1 files changed, 77 insertions, 0 deletions

diff --git a/xfs-Fix-possible-memory-corruption-in-xfs_readlink.patch b/xfs-Fix-possible-memory-corruption-in-xfs_readlink.patch
new file mode 100644
index 000000000..9e810dba8
--- /dev/null
+++ b/xfs-Fix-possible-memory-corruption-in-xfs_readlink.patch
@@ -0,0 +1,77 @@
+X-Spam-Checker-Version: SpamAssassin 3.4.0-r929098 (2010-03-30) on oss.sgi.com
+X-Spam-Level: 
+X-Spam-Status: No, score=-1.8 required=5.0 tests=BAYES_00,J_CHICKENPOX_64
+	autolearn=no version=3.4.0-r929098
+Received: from cuda.sgi.com (cuda1.sgi.com [192.48.157.11])
+	by oss.sgi.com (8.14.3/8.14.3/SuSE Linux 0.8) with ESMTP id p9I1KBVD036341
+	for <xfs@oss.sgi.com>; Mon, 17 Oct 2011 20:20:11 -0500
+X-ASG-Debug-ID: 1318901280-3911029d0000-NocioJ
+X-Barracuda-URL: http://cuda.sgi.com:80/cgi-bin/mark.cgi
+Received: from hades.usersys.redhat.com (localhost [127.0.0.1])
+	by cuda.sgi.com (Spam Firewall) with ESMTP id B9D1DF75F0A
+	for <xfs@oss.sgi.com>; Mon, 17 Oct 2011 18:28:01 -0700 (PDT)
+Received: from hades.usersys.redhat.com ([187.60.101.4]) by cuda.sgi.com with ESMTP id 81CuyNdYBqrtvtnD for <xfs@oss.sgi.com>; Mon, 17 Oct 2011 18:28:01 -0700 (PDT)
+Received: by hades.usersys.redhat.com (Postfix, from userid 500)
+	id 5B763E089B; Tue, 18 Oct 2011 02:18:59 -0200 (BRST)
+From: Carlos Maiolino <cmaiolino@redhat.com>
+To: xfs@oss.sgi.com
+Cc: Carlos Maiolino <cmaiolino@redhat.com>
+X-ASG-Orig-Subj: [PATCH] Fix possible memory corruption in xfs_readlink
+Subject: [PATCH] Fix possible memory corruption in xfs_readlink
+Date: Tue, 18 Oct 2011 02:18:58 -0200
+Message-Id: <1318911538-9174-1-git-send-email-cmaiolino@redhat.com>
+X-Mailer: git-send-email 1.7.6.2
+X-Barracuda-Connect: UNKNOWN[187.60.101.4]
+X-Barracuda-Start-Time: 1318901282
+X-Barracuda-Bayes: INNOCENT GLOBAL 0.0000 1.0000 -2.0210
+X-Barracuda-Virus-Scanned: by cuda.sgi.com at sgi.com
+X-Barracuda-Spam-Score: -1.42
+X-Barracuda-Spam-Status: No, SCORE=-1.42 using per-user scores of TAG_LEVEL=2.0 QUARANTINE_LEVEL=1000.0 KILL_LEVEL=2.1 tests=BSF_SC5_MJ1963, RDNS_NONE
+X-Barracuda-Spam-Report: Code version 3.2, rules version 3.2.2.77645
+	Rule breakdown below
+	 pts rule name              description
+	---- ---------------------- --------------------------------------------------
+	0.10 RDNS_NONE              Delivered to trusted network by a host with no rDNS
+	0.50 BSF_SC5_MJ1963         Custom Rule MJ1963
+X-Virus-Scanned: ClamAV version 0.94.2, clamav-milter version 0.94.2 on oss.sgi.com
+X-Virus-Status: Clean
+
+Fixes a possible memory corruption when the link is larger than
+MAXPATHLEN and XFS_DEBUG is not enabled. This also remove the
+S_ISLNK assert, since the inode mode is checked previously in
+xfs_readlink_by_handle() and via VFS.
+
+Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
+---
+ fs/xfs/xfs_vnodeops.c |   11 ++++++++---
+ 1 files changed, 8 insertions(+), 3 deletions(-)
+
+diff --git a/fs/xfs/xfs_vnodeops.c b/fs/xfs/xfs_vnodeops.c
+index 51fc429..c3288be 100644
+--- a/fs/xfs/xfs_vnodeops.c
++++ b/fs/xfs/xfs_vnodeops.c
+@@ -123,13 +123,18 @@ xfs_readlink(
+ 
+ 	xfs_ilock(ip, XFS_ILOCK_SHARED);
+ 
+-	ASSERT(S_ISLNK(ip->i_d.di_mode));
+-	ASSERT(ip->i_d.di_size <= MAXPATHLEN);
+-
+ 	pathlen = ip->i_d.di_size;
+ 	if (!pathlen)
+ 		goto out;
+ 
++	if (pathlen > MAXPATHLEN) {
++		xfs_alert(mp, "%s: inode (%llu) symlink length (%d) too long",
++			 __func__, (unsigned long long)ip->i_ino, pathlen);
++		ASSERT(0);
++		return XFS_ERROR(EFSCORRUPTED);
++	}
++
++
+ 	if (ip->i_df.if_flags & XFS_IFINLINE) {
+ 		memcpy(link, ip->i_df.if_u1.if_data, pathlen);
+ 		link[pathlen] = '\0';
+-- 
+1.7.6.2
+