From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from bombadil.infradead.org ([65.50.211.133]:49393 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753241AbdJSOXj (ORCPT ); Thu, 19 Oct 2017 10:23:39 -0400 From: Christoph Hellwig Subject: [PATCH 14/16] xfs: handle error if xfs_btree_get_bufs fails Date: Thu, 19 Oct 2017 16:22:57 +0200 Message-Id: <20171019142259.20082-15-hch@lst.de> In-Reply-To: <20171019142259.20082-1-hch@lst.de> References: <20171019142259.20082-1-hch@lst.de> Sender: linux-xfs-owner@vger.kernel.org List-ID: List-Id: xfs To: stable@vger.kernel.org Cc: linux-xfs@vger.kernel.org, Eric Sandeen , Eric Sandeen , "Darrick J . Wong" From: Eric Sandeen commit 93e8befc17f6d6ea92b0aee3741ceac8bca4590f upstream. Jason reported that a corrupted filesystem failed to replay the log with a metadata block out of bounds warning: XFS (dm-2): _xfs_buf_find: Block out of range: block 0x80270fff8, EOFS 0x9c40000 _xfs_buf_find() and xfs_btree_get_bufs() return NULL if that happens, and then when xfs_alloc_fix_freelist() calls xfs_trans_binval() on that NULL bp, we oops with: BUG: unable to handle kernel NULL pointer dereference at 00000000000000f8 We don't handle _xfs_buf_find errors very well, every caller higher up the stack gets to guess at why it failed. But we should at least handle it somehow, so return EFSCORRUPTED here. Reported-by: Jason L Tibbitts III Signed-off-by: Eric Sandeen Reviewed-by: Christoph Hellwig Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong --- fs/xfs/libxfs/xfs_alloc.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/fs/xfs/libxfs/xfs_alloc.c b/fs/xfs/libxfs/xfs_alloc.c index 9f06a211e157..c3702cda010a 100644 --- a/fs/xfs/libxfs/xfs_alloc.c +++ b/fs/xfs/libxfs/xfs_alloc.c @@ -1579,6 +1579,10 @@ xfs_alloc_ag_vextent_small( bp = xfs_btree_get_bufs(args->mp, args->tp, args->agno, fbno, 0); + if (!bp) { + error = -EFSCORRUPTED; + goto error0; + } xfs_trans_binval(args->tp, bp); } args->len = 1; @@ -2136,6 +2140,10 @@ xfs_alloc_fix_freelist( if (error) goto out_agbp_relse; bp = xfs_btree_get_bufs(mp, tp, args->agno, bno, 0); + if (!bp) { + error = -EFSCORRUPTED; + goto out_agbp_relse; + } xfs_trans_binval(tp, bp); } -- 2.14.2