On Wed, Nov 29, 2023 at 03:58:31PM +0800, Jiachen Zhang wrote:
> In the case of returning -ENOSPC, ensure logflagsp is initialized by 0.
> Otherwise the caller __xfs_bunmapi will set uninitialized illegal
> tmp_logflags value into xfs log, which might cause unpredictable error
> in the log recovery procedure.
>
> Also, remove the flags variable and set the *logflagsp directly, so that
> the code should be more robust in the long run.
>
> Fixes: 1b24b633aafe ("xfs: move some more code into xfs_bmap_del_extent_real")
> Signed-off-by: Jiachen Zhang <zhangjiachen.jaycee@xxxxxxxxxxxxx>
> Reviewed-by: Christoph Hellwig <hch@xxxxxx>
> ---
> fs/xfs/libxfs/xfs_bmap.c | 26 ++++++++++++++------------
> 1 file changed, 14 insertions(+), 12 deletions(-)
>
> diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c
> index be62acffad6c..9435bd6c950b 100644
> --- a/fs/xfs/libxfs/xfs_bmap.c
> +++ b/fs/xfs/libxfs/xfs_bmap.c
> @@ -5010,7 +5010,6 @@ xfs_bmap_del_extent_real(
> xfs_fileoff_t del_endoff; /* first offset past del */
> int do_fx; /* free extent at end of routine */
> int error; /* error return value */
> - int flags = 0;/* inode logging flags */
> struct xfs_bmbt_irec got; /* current extent entry */
> xfs_fileoff_t got_endoff; /* first offset past got */
> int i; /* temp state */
> @@ -5023,6 +5022,8 @@ xfs_bmap_del_extent_real(
> uint32_t state = xfs_bmap_fork_to_state(whichfork);
> struct xfs_bmbt_irec old;
>
> + *logflagsp = 0;
> +
> mp = ip->i_mount;
> XFS_STATS_INC(mp, xs_del_exlist);
>
> @@ -5048,10 +5049,12 @@ xfs_bmap_del_extent_real(
> if (tp->t_blk_res == 0 &&
> ifp->if_format == XFS_DINODE_FMT_EXTENTS &&
> ifp->if_nextents >= XFS_IFORK_MAXEXT(ip, whichfork) &&
> - del->br_startoff > got.br_startoff && del_endoff < got_endoff)
> - return -ENOSPC;
> + del->br_startoff > got.br_startoff && del_endoff < got_endoff) {
> + error = -ENOSPC;
> + goto done;
> + }
Now that you've added initialisation of logflagsp, the need for the
error stacking goto pattern goes away completely. Anywhere that has
a "goto done" can be converted to a direct 'return error' call and
the done label can be removed.
-Dave.
--
Dave Chinner
david@xxxxxxxxxxxxx
