From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f43.google.com ([209.85.220.43]:33315 "EHLO mail-pa0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933707AbbBQKvc (ORCPT ); Tue, 17 Feb 2015 05:51:32 -0500 Received: by pabkx10 with SMTP id kx10so5491548pab.0 for ; Tue, 17 Feb 2015 02:51:32 -0800 (PST) From: Omar Sandoval To: Chris Mason , Josef Bacik , David Sterba Cc: linux-btrfs@vger.kernel.org, linux-kernel@vger.kernel.org, Omar Sandoval Subject: [PATCH 3/3] btrfs: check io_ctl_prepare_pages return in __btrfs_write_out_cache Date: Tue, 17 Feb 2015 02:51:09 -0800 Message-Id: In-Reply-To: References: In-Reply-To: References: Sender: linux-btrfs-owner@vger.kernel.org List-ID: If io_ctl_prepare_pages fails, the pages in io_ctl.pages are not valid. When we try to access them later, things will blow up in various ways. Signed-off-by: Omar Sandoval --- fs/btrfs/free-space-cache.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c index d6c03f7..0460632 100644 --- a/fs/btrfs/free-space-cache.c +++ b/fs/btrfs/free-space-cache.c @@ -1114,7 +1114,7 @@ cleanup_write_cache_enospc(struct inode *inode, * * This function writes out a free space cache struct to disk for quick recovery * on mount. This will return 0 if it was successfull in writing the cache out, - * and -1 if it was not. + * or an errno if it was not. */ static int __btrfs_write_out_cache(struct btrfs_root *root, struct inode *inode, struct btrfs_free_space_ctl *ctl, @@ -1130,11 +1130,11 @@ static int __btrfs_write_out_cache(struct btrfs_root *root, struct inode *inode, int ret; if (!i_size_read(inode)) - return -1; + return -EIO; ret = io_ctl_init(&io_ctl, inode, root, 1); if (ret) - return -1; + return ret; if (block_group && (block_group->flags & BTRFS_BLOCK_GROUP_DATA)) { down_write(&block_group->data_rwsem); @@ -1151,7 +1151,9 @@ static int __btrfs_write_out_cache(struct btrfs_root *root, struct inode *inode, } /* Lock all pages first so we can lock the extent safely. */ - io_ctl_prepare_pages(&io_ctl, inode, 0); + ret = io_ctl_prepare_pages(&io_ctl, inode, 0); + if (ret) + goto out; lock_extent_bits(&BTRFS_I(inode)->io_tree, 0, i_size_read(inode) - 1, 0, &cached_state); -- 2.3.0