From 60979115a69e0e7916a1c1796f902264f1350977 Mon Sep 17 00:00:00 2001 From: Jaegeuk Kim Date: Sat, 13 Sep 2014 00:35:58 +0900 Subject: f2fs: fix double lock for inode page during roll-foward recovery If the inode is same and its data index are needed to truncate, we can fall into double lock for its inode page via get_dnode_of_data. Error case is like this. 1. write data 1, 2, 3, 4, 5 in inode #4. 2. write data 100, 102, 103, 104, 105 in dnode #6 of inode #4. 3. sync 4. update data 100->106 in dnode #6. 5. fsync inode #4. 6. power-cut -> Then, 1. go back to #3's checkpoint 2. in do_recover_data, get_dnode_of_data() gets inode #4. 3. detect 100->106 in dnode #6. 4. check_index_in_prev_nodes tries to truncate 100 in dnode #6. 5. to trigger truncate_hole, get_dnode_of_data should grab inode #4. 6. detect *kernel hang* This patch should resolve that bug. Signed-off-by: Jaegeuk Kim --- fs/f2fs/recovery.c | 28 +++++++++++++++++++++------- 1 file changed, 21 insertions(+), 7 deletions(-) (limited to 'fs/f2fs') diff --git a/fs/f2fs/recovery.c b/fs/f2fs/recovery.c index 6c5a74a45f33..e587ee128e17 100644 --- a/fs/f2fs/recovery.c +++ b/fs/f2fs/recovery.c @@ -279,16 +279,30 @@ got_it: ino = ino_of_node(node_page); f2fs_put_page(node_page, 1); - /* Deallocate previous index in the node page */ - inode = f2fs_iget(sbi->sb, ino); - if (IS_ERR(inode)) - return PTR_ERR(inode); + if (ino != dn->inode->i_ino) { + /* Deallocate previous index in the node page */ + inode = f2fs_iget(sbi->sb, ino); + if (IS_ERR(inode)) + return PTR_ERR(inode); + } else { + inode = dn->inode; + } bidx = start_bidx_of_node(offset, F2FS_I(inode)) + - le16_to_cpu(sum.ofs_in_node); + le16_to_cpu(sum.ofs_in_node); - truncate_hole(inode, bidx, bidx + 1); - iput(inode); + if (ino != dn->inode->i_ino) { + truncate_hole(inode, bidx, bidx + 1); + iput(inode); + } else { + struct dnode_of_data tdn; + set_new_dnode(&tdn, inode, dn->inode_page, NULL, 0); + if (get_dnode_of_data(&tdn, bidx, LOOKUP_NODE)) + return 0; + if (tdn.data_blkaddr != NULL_ADDR) + truncate_data_blocks_range(&tdn, 1); + f2fs_put_page(tdn.node_page, 1); + } return 0; } -- cgit v1.2.3