diff options
| author | Jan Kara <jack@suse.cz> | 2017-06-13 16:20:25 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-07-27 15:08:06 -0700 |
| commit | fa67ac18eff4b59b7937c59e821f8b4be812113c (patch) | |
| tree | 6fd2547f0ad423c249cb8a531b066b6908b4819a | |
| parent | 9ebfb4fa3ab7ea99b5d93305b10ee3714501b465 (diff) | |
udf: Fix deadlock between writeback and udf_setsize()
commit f2e95355891153f66d4156bf3a142c6489cd78c6 upstream.
udf_setsize() called truncate_setsize() with i_data_sem held. Thus
truncate_pagecache() called from truncate_setsize() could lock a page
under i_data_sem which can deadlock as page lock ranks below
i_data_sem - e. g. writeback can hold page lock and try to acquire
i_data_sem to map a block.
Fix the problem by moving truncate_setsize() calls from under
i_data_sem. It is safe for us to change i_size without holding
i_data_sem as all the places that depend on i_size being stable already
hold inode_lock.
Fixes: 7e49b6f2480cb9a9e7322a91592e56a5c85361f5
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | fs/udf/inode.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/fs/udf/inode.c b/fs/udf/inode.c index 129b18a29c8f..035943501b9f 100644 --- a/fs/udf/inode.c +++ b/fs/udf/inode.c @@ -1243,8 +1243,8 @@ int udf_setsize(struct inode *inode, loff_t newsize) return err; } set_size: - truncate_setsize(inode, newsize); up_write(&iinfo->i_data_sem); + truncate_setsize(inode, newsize); } else { if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) { down_write(&iinfo->i_data_sem); @@ -1261,9 +1261,9 @@ set_size: udf_get_block); if (err) return err; + truncate_setsize(inode, newsize); down_write(&iinfo->i_data_sem); udf_clear_extent_cache(inode); - truncate_setsize(inode, newsize); udf_truncate_extents(inode); up_write(&iinfo->i_data_sem); } |