From: Christoph Hellwig Date: Sun, 2 Oct 2016 22:47:34 +0000 (+1100) Subject: xfs: update atime before I/O in xfs_file_dio_aio_read X-Git-Tag: v4.9-rc1~31^2~77 X-Git-Url: http://git.cascardo.info/?p=cascardo%2Flinux.git;a=commitdiff_plain;h=a447d7cd15c759d8ab7f3c9c8183aa8c999d7ed4 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 Reported-and-tested-by: Darrick J. Wong Reviewed-by: Darrick J. Wong Signed-off-by: Dave Chinner --- diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c index e612a0233710..b927ea9abe33 100644 --- a/fs/xfs/xfs_file.c +++ b/fs/xfs/xfs_file.c @@ -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; }