From 779e26517b3600830fe58933d5f97627711c9435 Mon Sep 17 00:00:00 2001 From: Eric Whitney Date: Thu, 30 Apr 2020 14:53:19 -0400 Subject: ext4: clean up GET_BLOCKS_PRE_IO error handling If the call to ext4_split_convert_extents() fails in the EXT4_GET_BLOCKS_PRE_IO case within ext4_ext_handle_unwritten_extents(), error out through the exit point at function end rather than jumping through an intermediate point. Fix the error handling in the event ext4_split_convert_extents() returns 0, which it shouldn't do when splitting an existing extent. The current code returns the passed in value of allocated (which is likely non-zero) while failing to set m_flags, m_pblk, and m_len. Signed-off-by: Eric Whitney Link: https://lore.kernel.org/r/20200430185320.23001-4-enwlinux@gmail.com Signed-off-by: Theodore Ts'o --- fs/ext4/extents.c | 26 ++++++++++++++++++++------ 1 file changed, 20 insertions(+), 6 deletions(-) (limited to 'fs') diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index 57f02e2d2f52..c63bc13f9a72 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -3818,12 +3818,25 @@ ext4_ext_handle_unwritten_extents(handle_t *handle, struct inode *inode, trace_ext4_ext_handle_unwritten_extents(inode, map, flags, allocated, newblock); - /* get_block() before submit the IO, split the extent */ + /* get_block() before submitting IO, split the extent */ if (flags & EXT4_GET_BLOCKS_PRE_IO) { ret = ext4_split_convert_extents(handle, inode, map, ppath, flags | EXT4_GET_BLOCKS_CONVERT); - if (ret <= 0) - goto out; + if (ret < 0) { + err = ret; + goto out2; + } + /* + * shouldn't get a 0 return when splitting an extent unless + * m_len is 0 (bug) or extent has been corrupted + */ + if (unlikely(ret == 0)) { + EXT4_ERROR_INODE(inode, + "unexpected ret == 0, m_len = %u", + map->m_len); + err = -EFSCORRUPTED; + goto out2; + } map->m_flags |= EXT4_MAP_UNWRITTEN; goto out; } @@ -3863,12 +3876,13 @@ ext4_ext_handle_unwritten_extents(handle_t *handle, struct inode *inode, ret = ext4_ext_convert_to_initialized(handle, inode, map, ppath, flags); if (ret >= 0) ext4_update_inode_fsync_trans(handle, inode, 1); -out: + if (ret <= 0) { err = ret; goto out2; - } else - allocated = ret; + } +out: + allocated = ret; map->m_flags |= EXT4_MAP_NEW; map_out: map->m_flags |= EXT4_MAP_MAPPED; -- cgit v1.2.3