3.16.58-rc1 review patch. If anyone has any objections, please let me know.
------------------
From: Eric Sandeen sandeen@redhat.com
commit 2c4306f719b083d17df2963bc761777576b8ad1b upstream.
If xfs_bmap_extents_to_btree fails in a mode where we call xfs_iroot_realloc(-1) to de-allocate the root, set the format back to extents.
Otherwise we can assume we can dereference ifp->if_broot based on the XFS_DINODE_FMT_BTREE format, and crash.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=199423 Signed-off-by: Eric Sandeen sandeen@redhat.com Reviewed-by: Christoph Hellwig hch@lst.de Reviewed-by: Darrick J. Wong darrick.wong@oracle.com Signed-off-by: Darrick J. Wong darrick.wong@oracle.com [bwh: Backported to 3.16: - Only one failure path needs to be patched - Adjust filename] Signed-off-by: Ben Hutchings ben@decadent.org.uk --- fs/xfs/xfs_bmap.c | 4 ++++ 1 file changed, 4 insertions(+)
--- a/fs/xfs/xfs_bmap.c +++ b/fs/xfs/xfs_bmap.c @@ -822,6 +822,8 @@ xfs_bmap_extents_to_btree( *logflagsp = 0; if ((error = xfs_alloc_vextent(&args))) { xfs_iroot_realloc(ip, -1, whichfork); + ASSERT(ifp->if_broot == NULL); + XFS_IFORK_FMT_SET(ip, whichfork, XFS_DINODE_FMT_EXTENTS); xfs_btree_del_cursor(cur, XFS_BTREE_ERROR); return error; }