From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-00082601.pphosted.com ([67.231.145.42]:43130 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754710AbbDGPYj (ORCPT ); Tue, 7 Apr 2015 11:24:39 -0400 Received: from pps.filterd (m0004348 [127.0.0.1]) by m0004348.ppops.net (8.14.5/8.14.5) with SMTP id t37FOZrf031341 for ; Tue, 7 Apr 2015 08:24:38 -0700 Received: from mail.thefacebook.com ([199.201.64.23]) by m0004348.ppops.net with ESMTP id 1tmghpg62v-5 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=NOT) for ; Tue, 07 Apr 2015 08:24:38 -0700 Date: Tue, 7 Apr 2015 11:24:24 -0400 From: Chris Mason To: Subject: [PATCH v2] Btrfs: fix use after free when close_ctree frees the orphan_rsv Message-ID: <20150407152424.GA11741@ret.masoncoding.com> References: <20150407150926.GA10738@ret.masoncoding.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" In-Reply-To: <20150407150926.GA10738@ret.masoncoding.com> Sender: linux-btrfs-owner@vger.kernel.org List-ID: >>From 471717f48f9d853a6ced290d91e8b7f1d1c039da Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Mon, 6 Apr 2015 18:17:00 -0700 Subject: [PATCH] Btrfs: fix use after free when close_ctree frees the orphan_rsv Near the end of close_ctree, we're calling btrfs_free_block_rsv to free up the orphan rsv. The problem is this call updates the space_info, which has already been freed. This adds a new __ function that directly calls kfree instead of trying to update the space infos. Signed-off-by: Chris Mason --- v1 -> v2: whoops, get __btrfs-free_block_rsv in the right commit fs/btrfs/ctree.h | 1 + fs/btrfs/disk-io.c | 2 +- fs/btrfs/extent-tree.c | 7 +++++++ 3 files changed, 9 insertions(+), 1 deletion(-) diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index e1800d4..21032ed 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -3488,6 +3488,7 @@ struct btrfs_block_rsv *btrfs_alloc_block_rsv(struct btrfs_root *root, unsigned short type); void btrfs_free_block_rsv(struct btrfs_root *root, struct btrfs_block_rsv *rsv); +void __btrfs_free_block_rsv(struct btrfs_block_rsv *rsv); int btrfs_block_rsv_add(struct btrfs_root *root, struct btrfs_block_rsv *block_rsv, u64 num_bytes, enum btrfs_reserve_flush_enum flush); diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index bb589b5..a123626 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -3746,7 +3746,7 @@ void close_ctree(struct btrfs_root *root) btrfs_free_stripe_hash_table(fs_info); - btrfs_free_block_rsv(root, root->orphan_block_rsv); + __btrfs_free_block_rsv(root->orphan_block_rsv); root->orphan_block_rsv = NULL; lock_chunks(root); diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 9a53afc..0f1be4a 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -4925,6 +4925,13 @@ void btrfs_free_block_rsv(struct btrfs_root *root, kfree(rsv); } +void __btrfs_free_block_rsv(struct btrfs_block_rsv *rsv) +{ + if (!rsv) + return; + kfree(rsv); +} + int btrfs_block_rsv_add(struct btrfs_root *root, struct btrfs_block_rsv *block_rsv, u64 num_bytes, enum btrfs_reserve_flush_enum flush) -- 1.8.1