Commit a447d7cd authored Oct 03, 2016 by Christoph Hellwig Committed by Dave Chinner Oct 03, 2016

xfs: update atime before I/O in xfs_file_dio_aio_read



After the call to __blkdev_direct_IO the final reference to the file
might have been dropped by aio_complete already, and the call to
file_accessed might cause a use after free.

Instead update the access time before the I/O, similar to how we
update the time stamps before writes.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-and-tested-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>

parent 5694fe9a

fs/xfs/xfs_file.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -269,6 +269,8 @@ xfs_file_dio_aio_read(
		return -EINVAL;
		}

		file_accessed(iocb->ki_filp);

		/*
		* Locking is a bit tricky here. If we take an exclusive lock for direct
		* IO, we effectively serialise all new concurrent read IO to this file
		@@ -323,7 +325,6 @@ xfs_file_dio_aio_read(
		}
		xfs_rw_iunlock(ip, XFS_IOLOCK_SHARED);

		file_accessed(iocb->ki_filp);
		return ret;
		}