diff options
| author | Wengang Wang <wen.gang.wang@oracle.com> | 2014-06-23 13:22:08 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-06-23 16:47:45 -0700 |
| commit | 8a8ad1c2f6ef6fbee7487ec293218f42e72ad6a3 (patch) | |
| tree | 02c7a79e46deda38a1be826d93a3463e1c5d79eb | |
| parent | b253bfd87866a38e11baf9b88c9d54c534cd70cd (diff) | |
ocfs2: refcount: take rw_lock in ocfs2_reflink
This patch tries to fix this crash:
#5 [ffff88003c1cd690] do_invalid_op at ffffffff810166d5
#6 [ffff88003c1cd730] invalid_op at ffffffff8159b2de
[exception RIP: ocfs2_direct_IO_get_blocks+359]
RIP: ffffffffa05dfa27 RSP: ffff88003c1cd7e8 RFLAGS: 00010202
RAX: 0000000000000000 RBX: ffff88003c1cdaa8 RCX: 0000000000000000
RDX: 000000000000000c RSI: ffff880027a95000 RDI: ffff88003c79b540
RBP: ffff88003c1cd858 R8: 0000000000000000 R9: ffffffff815f6ba0
R10: 00000000000001c9 R11: 00000000000001c9 R12: ffff88002d271500
R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000001000
ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018
#7 [ffff88003c1cd860] do_direct_IO at ffffffff811cd31b
#8 [ffff88003c1cd950] direct_IO_iovec at ffffffff811cde9c
#9 [ffff88003c1cd9b0] do_blockdev_direct_IO at ffffffff811ce764
#10 [ffff88003c1cdb80] __blockdev_direct_IO at ffffffff811ce7cc
#11 [ffff88003c1cdbb0] ocfs2_direct_IO at ffffffffa05df756 [ocfs2]
#12 [ffff88003c1cdbe0] generic_file_direct_write_iter at ffffffff8112f935
#13 [ffff88003c1cdc40] ocfs2_file_write_iter at ffffffffa0600ccc [ocfs2]
#14 [ffff88003c1cdd50] do_aio_write at ffffffff8119126c
#15 [ffff88003c1cddc0] aio_rw_vect_retry at ffffffff811d9bb4
#16 [ffff88003c1cddf0] aio_run_iocb at ffffffff811db880
#17 [ffff88003c1cde30] io_submit_one at ffffffff811dc238
#18 [ffff88003c1cde80] do_io_submit at ffffffff811dc437
#19 [ffff88003c1cdf70] sys_io_submit at ffffffff811dc530
#20 [ffff88003c1cdf80] system_call_fastpath at ffffffff8159a159
It crashes at
BUG_ON(create && (ext_flags & OCFS2_EXT_REFCOUNTED));
in ocfs2_direct_IO_get_blocks.
ocfs2_direct_IO_get_blocks is expecting the OCFS2_EXT_REFCOUNTED be removed in
ocfs2_prepare_inode_for_write() if it was there. But no cluster lock is taken
during the time before (or inside) ocfs2_prepare_inode_for_write() and after
ocfs2_direct_IO_get_blocks().
It can happen in this case:
Node A(which crashes) Node B
------------------------ ---------------------------
ocfs2_file_aio_write
ocfs2_prepare_inode_for_write
ocfs2_inode_lock
...
ocfs2_inode_unlock
#no refcount found
.... ocfs2_reflink
ocfs2_inode_lock
...
ocfs2_inode_unlock
#now, refcount flag set on extent
...
flush change to disk
ocfs2_direct_IO_get_blocks
ocfs2_get_clusters
#extent map miss
#buffer_head miss
read extents from disk
found refcount flag on extent
crash..
Fix:
Take rw_lock in ocfs2_reflink path
Signed-off-by: Wengang Wang <wen.gang.wang@oracle.com>
Reviewed-by: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | fs/ocfs2/refcounttree.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/fs/ocfs2/refcounttree.c b/fs/ocfs2/refcounttree.c index 714e53b9cc6..636aab69ead 100644 --- a/fs/ocfs2/refcounttree.c +++ b/fs/ocfs2/refcounttree.c @@ -4288,9 +4288,16 @@ static int ocfs2_reflink(struct dentry *old_dentry, struct inode *dir, goto out; } + error = ocfs2_rw_lock(inode, 1); + if (error) { + mlog_errno(error); + goto out; + } + error = ocfs2_inode_lock(inode, &old_bh, 1); if (error) { mlog_errno(error); + ocfs2_rw_unlock(inode, 1); goto out; } @@ -4302,6 +4309,7 @@ static int ocfs2_reflink(struct dentry *old_dentry, struct inode *dir, up_write(&OCFS2_I(inode)->ip_xattr_sem); ocfs2_inode_unlock(inode, 1); + ocfs2_rw_unlock(inode, 1); brelse(old_bh); if (error) { |