diff mbox

[2/2] udf: Check length of extended attributes and allocation descriptors

Message ID 1433509796-19402-3-git-send-email-luis.henriques@canonical.com
State New
Headers show

Commit Message

Luis Henriques June 5, 2015, 1:09 p.m. UTC 
From: Jan Kara <jack@suse.cz>

Check length of extended attributes and allocation descriptors when
loading inodes from disk. Otherwise corrupted filesystems could confuse
the code and make the kernel oops.

Reported-by: Carl Henrik Lunde <chlunde@ping.uio.no>
CC: stable@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
(backported from commit 23b133bdc452aa441fcb9b82cbf6dd05cfd342d0)
CVE-2015-4167
BugLink: https://bugs.launchpad.net/bugs/1462173
[ luis: used Ben's backport to 3.16:
  - use make_bad_inode() instead of returning error ]
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
---
 fs/udf/inode.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)
diff mbox

Patch

diff --git a/fs/udf/inode.c b/fs/udf/inode.c
index ca0370c4334f..29ac38e52bfe 100644
--- a/fs/udf/inode.c
+++ b/fs/udf/inode.c
@@ -1481,6 +1481,19 @@  reread:
 		iinfo->i_checkpoint = le32_to_cpu(efe->checkpoint);
 	}
 
+	/*
+	 * Sanity check length of allocation descriptors and extended attrs to
+	 * avoid integer overflows
+	 */
+	if (iinfo->i_lenEAttr > bs || iinfo->i_lenAlloc > bs) {
+		make_bad_inode(inode);
+		return;
+	}
+	/* Now do exact checks */
+	if (udf_file_entry_alloc_offset(inode) + iinfo->i_lenAlloc > bs) {
+		make_bad_inode(inode);
+		return;
+	}
 	/* Sanity checks for files in ICB so that we don't get confused later */
 	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
 		/*