From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from out1-smtp.messagingengine.com ([66.111.4.25]:40223 "EHLO out1-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750942AbbJWOP6 (ORCPT ); Fri, 23 Oct 2015 10:15:58 -0400 Received: from compute4.internal (compute4.nyi.internal [10.202.2.44]) by mailout.nyi.internal (Postfix) with ESMTP id 9D4032092C for ; Fri, 23 Oct 2015 10:15:57 -0400 (EDT) Subject: FAILED: patch "[PATCH] btrfs: fix use after free iterating extrefs" failed to apply to 3.10-stable tree To: clm@fb.com, fdmanana@suse.com, mfasheh@suse.de Cc: From: Date: Fri, 23 Oct 2015 07:15:56 -0700 Message-ID: <1445609756180187@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: The patch below does not apply to the 3.10-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >>From dc6c5fb3b514221f2e9d21ee626a9d95d3418dff Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Tue, 13 Oct 2015 14:06:48 -0400 Subject: [PATCH] btrfs: fix use after free iterating extrefs The code for btrfs inode-resolve has never worked properly for files with enough hard links to trigger extrefs. It was trying to get the leaf out of a path after freeing the path: btrfs_release_path(path); leaf = path->nodes[0]; item_size = btrfs_item_size_nr(leaf, slot); The fix here is to use the extent buffer we cloned just a little higher up to avoid deadlocks caused by using the leaf in the path. Signed-off-by: Chris Mason cc: stable@vger.kernel.org # v3.7+ cc: Mark Fasheh Reviewed-by: Filipe Manana Reviewed-by: Mark Fasheh diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c index ecbc63d3143e..9a2ec79e8cfb 100644 --- a/fs/btrfs/backref.c +++ b/fs/btrfs/backref.c @@ -1828,7 +1828,6 @@ static int iterate_inode_extrefs(u64 inum, struct btrfs_root *fs_root, int found = 0; struct extent_buffer *eb; struct btrfs_inode_extref *extref; - struct extent_buffer *leaf; u32 item_size; u32 cur_offset; unsigned long ptr; @@ -1856,9 +1855,8 @@ static int iterate_inode_extrefs(u64 inum, struct btrfs_root *fs_root, btrfs_set_lock_blocking_rw(eb, BTRFS_READ_LOCK); btrfs_release_path(path); - leaf = path->nodes[0]; - item_size = btrfs_item_size_nr(leaf, slot); - ptr = btrfs_item_ptr_offset(leaf, slot); + item_size = btrfs_item_size_nr(eb, slot); + ptr = btrfs_item_ptr_offset(eb, slot); cur_offset = 0; while (cur_offset < item_size) { @@ -1872,7 +1870,7 @@ static int iterate_inode_extrefs(u64 inum, struct btrfs_root *fs_root, if (ret) break; - cur_offset += btrfs_inode_extref_name_len(leaf, extref); + cur_offset += btrfs_inode_extref_name_len(eb, extref); cur_offset += sizeof(*extref); } btrfs_tree_read_unlock_blocking(eb);