Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932789Ab2KZSCE (ORCPT ); Mon, 26 Nov 2012 13:02:04 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:47447 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932509Ab2KZRFd (ORCPT ); Mon, 26 Nov 2012 12:05:33 -0500 From: Herton Ronaldo Krzesinski To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Xi Wang , Herton Ronaldo Krzesinski Subject: [PATCH 092/270] libceph: fix overflow in __decode_pool_names() Date: Mon, 26 Nov 2012 14:56:22 -0200 Message-Id: <1353949160-26803-93-git-send-email-herton.krzesinski@canonical.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1353949160-26803-1-git-send-email-herton.krzesinski@canonical.com> References: <1353949160-26803-1-git-send-email-herton.krzesinski@canonical.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1927 Lines: 60 3.5.7u1 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Xi Wang commit ad3b904c07dfa88603689bf9a67bffbb9b99beb5 upstream. `len' is read from network and thus needs validation. Otherwise a large `len' would cause out-of-bounds access via the memcpy() call. In addition, len = 0xffffffff would overflow the kmalloc() size, leading to out-of-bounds write. This patch adds a check of `len' via ceph_decode_need(). Also use kstrndup rather than kmalloc/memcpy. [elder@inktank.com: added -ENOMEM return for null kstrndup() result] Signed-off-by: Xi Wang Reviewed-by: Alex Elder Signed-off-by: Herton Ronaldo Krzesinski --- net/ceph/osdmap.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) diff --git a/net/ceph/osdmap.c b/net/ceph/osdmap.c index 81e3b84..95b2762 100644 --- a/net/ceph/osdmap.c +++ b/net/ceph/osdmap.c @@ -488,15 +488,16 @@ static int __decode_pool_names(void **p, void *end, struct ceph_osdmap *map) ceph_decode_32_safe(p, end, pool, bad); ceph_decode_32_safe(p, end, len, bad); dout(" pool %d len %d\n", pool, len); + ceph_decode_need(p, end, len, bad); pi = __lookup_pg_pool(&map->pg_pools, pool); if (pi) { + char *name = kstrndup(*p, len, GFP_NOFS); + + if (!name) + return -ENOMEM; kfree(pi->name); - pi->name = kmalloc(len + 1, GFP_NOFS); - if (pi->name) { - memcpy(pi->name, *p, len); - pi->name[len] = '\0'; - dout(" name is %s\n", pi->name); - } + pi->name = name; + dout(" name is %s\n", pi->name); } *p += len; } -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/