Commit cfaf2d03 authored Jul 24, 2017 by Brian Foster Committed by Darrick J. Wong Jul 24, 2017

xfs: fix quotacheck dquot id overflow infinite loop



If a dquot has an id of U32_MAX, the next lookup index increment
overflows the uint32_t back to 0. This starts the lookup sequence
over from the beginning, repeats indefinitely and results in a
livelock.

Update xfs_qm_dquot_walk() to explicitly check for the lookup
overflow and exit the loop.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

parent 10479e2d

fs/xfs/xfs_qm.c

+3 −0

Original line number	Diff line number	Diff line
		@@ -111,6 +111,9 @@ xfs_qm_dquot_walk(
		skipped = 0;
		break;
		}
		/* we're done if id overflows back to zero */
		if (!next_index)
		break;
		}

		if (skipped) {