xfs: bulkstat doesn't release AGI buffer on error

The recent refactoring of the bulkstat code left a small landmine in
the code. If a inobt read fails, then the tree walk is aborted and
returns without releasing the AGI buffer or freeing the cursor. This
can lead to a subsequent bulkstat call hanging trying to grab the
AGI buffer again.

cc: <stable@vger.kernel.org>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
This commit is contained in:
Dave Chinner 2014-10-29 08:22:18 +11:00 committed by Dave Chinner
parent cac7f24298
commit a6bbce54ef
1 changed files with 10 additions and 6 deletions

View File

@ -427,7 +427,7 @@ xfs_bulkstat(
error = xfs_bulkstat_grab_ichunk(cur, agino, &icount, &r);
if (error)
break;
goto del_cursor;
if (icount) {
irbp->ir_startino = r.ir_startino;
irbp->ir_freecount = r.ir_freecount;
@ -442,7 +442,7 @@ xfs_bulkstat(
error = xfs_inobt_lookup(cur, 0, XFS_LOOKUP_GE, &tmp);
}
if (error)
break;
goto del_cursor;
/*
* Loop through inode btree records in this ag,
@ -454,7 +454,7 @@ xfs_bulkstat(
error = xfs_inobt_get_rec(cur, &r, &i);
if (error || i == 0) {
end_of_ag = 1;
break;
goto del_cursor;
}
/*
@ -476,13 +476,17 @@ xfs_bulkstat(
error = xfs_btree_increment(cur, 0, &tmp);
cond_resched();
}
/*
* Drop the btree buffers and the agi buffer.
* We can't hold any of the locks these represent
* when calling iget.
* Drop the btree buffers and the agi buffer as we can't hold any
* of the locks these represent when calling iget. If there is a
* pending error, then we are done.
*/
del_cursor:
xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
xfs_buf_relse(agbp);
if (error)
break;
/*
* Now format all the good inodes into the user's buffer.
*/