linux-kernel - [PATCH 4.18 114/145] ubifs: Check data node size before truncate

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20180907210912.789676597@linuxfoundation.org>
Date:   Fri,  7 Sep 2018 23:09:40 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Kees Cook <keescook@...omium.org>,
        Silvio Cesare <silvio.cesare@...il.com>,
        Richard Weinberger <richard@....at>
Subject: [PATCH 4.18 114/145] ubifs: Check data node size before truncate

4.18-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Richard Weinberger <richard@....at>

commit 95a22d2084d72ea067d8323cc85677dba5d97cae upstream.

Check whether the size is within bounds before using it.
If the size is not correct, abort and dump the bad data node.

Cc: Kees Cook <keescook@...omium.org>
Cc: Silvio Cesare <silvio.cesare@...il.com>
Cc: stable@...r.kernel.org
Fixes: 1e51764a3c2ac ("UBIFS: add new flash file system")
Reported-by: Silvio Cesare <silvio.cesare@...il.com>
Signed-off-by: Richard Weinberger <richard@....at>
Reviewed-by: Kees Cook <keescook@...omium.org>
Signed-off-by: Richard Weinberger <richard@....at>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>

---
 fs/ubifs/journal.c |   11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

--- a/fs/ubifs/journal.c
+++ b/fs/ubifs/journal.c
@@ -1387,7 +1387,16 @@ int ubifs_jnl_truncate(struct ubifs_info
 		else if (err)
 			goto out_free;
 		else {
-			if (le32_to_cpu(dn->size) <= dlen)
+			int dn_len = le32_to_cpu(dn->size);
+
+			if (dn_len <= 0 || dn_len > UBIFS_BLOCK_SIZE) {
+				ubifs_err(c, "bad data node (block %u, inode %lu)",
+					  blk, inode->i_ino);
+				ubifs_dump_node(c, dn);
+				goto out_free;
+			}
+
+			if (dn_len <= dlen)
 				dlen = 0; /* Nothing to do */
 			else {
 				err = truncate_data_node(c, inode, blk, dn, &dlen);