diff options
| author | Theodore Ts'o <tytso@mit.edu> | 2011-12-12 10:53:02 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-12-21 12:58:33 -0800 |
| commit | 6415da6d18a55702cee3f01662733d0501635bbc (patch) | |
| tree | e475b41774ea3f1310d0c28843bc6a26a6286946 | |
| parent | d7587810a40aee32ec6bdfc2d4bce7ba9fd03c3e (diff) | |
ext4: fix ext4_end_io_dio() racing against fsync()
commit b5a7e97039a80fae673ccc115ce595d5b88fb4ee upstream.
We need to make sure iocb->private is cleared *before* we put the
io_end structure on i_completed_io_list. Otherwise fsync() could
potentially run on another CPU and free the iocb structure out from
under us.
Reported-by: Kent Overstreet <koverstreet@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| -rw-r--r-- | fs/ext4/inode.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index b644b9c164a7..00de8e8a133d 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -2630,10 +2630,11 @@ static void ext4_end_io_dio(struct kiocb *iocb, loff_t offset, iocb->private, io_end->inode->i_ino, iocb, offset, size); + iocb->private = NULL; + /* if not aio dio with unwritten extents, just free io and return */ if (!(io_end->flag & EXT4_IO_END_UNWRITTEN)) { ext4_free_io_end(io_end); - iocb->private = NULL; out: if (is_async) aio_complete(iocb, ret, 0); @@ -2656,7 +2657,6 @@ out: spin_unlock_irqrestore(&ei->i_completed_io_lock, flags); /* queue the work to convert unwritten extents to written */ - iocb->private = NULL; queue_work(wq, &io_end->work); /* XXX: probably should move into the real I/O completion handler */ |