diff options
| author | Baokun Li <[email protected]> | 2024-08-22 10:35:22 +0800 |
|---|---|---|
| committer | Theodore Ts'o <[email protected]> | 2024-09-03 22:12:16 -0400 |
| commit | 3e8a584c82cc999b99ea17c31fc2da101201545f (patch) | |
| tree | 05dc3408262d27639dec41d5e25132d8c29d94a0 | |
| parent | edfa71dbe841075109e3e1da7d3925b45328ed25 (diff) | |
ext4: prevent partial update of the extents path
In ext4_ext_rm_idx() and ext4_ext_correct_indexes(), there is no proper
rollback of already executed updates when updating a level of the extents
path fails, so we may get an inconsistent extents tree, which may trigger
some bad things in errors=continue mode.
Hence clear the verified bit of modified extents buffers if the tree fails
to be updated in ext4_ext_rm_idx() or ext4_ext_correct_indexes(), which
forces the extents buffers to be checked in ext4_valid_extent_entries(),
ensuring that the extents tree is consistent.
Signed-off-by: zhanchengbin <[email protected]>
Link: https://lore.kernel.org/r/[email protected]/
Signed-off-by: Baokun Li <[email protected]>
Reviewed-by: Jan Kara <[email protected]>
Reviewed-by: Ojaswin Mujoo <[email protected]>
Tested-by: Ojaswin Mujoo <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Theodore Ts'o <[email protected]>
| -rw-r--r-- | fs/ext4/extents.c | 31 |
1 files changed, 27 insertions, 4 deletions
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index ca08b4036e28..4395e2b668ec 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -1749,12 +1749,23 @@ static int ext4_ext_correct_indexes(handle_t *handle, struct inode *inode, break; err = ext4_ext_get_access(handle, inode, path + k); if (err) - break; + goto clean; path[k].p_idx->ei_block = border; err = ext4_ext_dirty(handle, inode, path + k); if (err) - break; + goto clean; } + return 0; + +clean: + /* + * The path[k].p_bh is either unmodified or with no verified bit + * set (see ext4_ext_get_access()). So just clear the verified bit + * of the successfully modified extents buffers, which will force + * these extents to be checked to avoid using inconsistent data. + */ + while (++k < depth) + clear_buffer_verified(path[k].p_bh); return err; } @@ -2312,12 +2323,24 @@ static int ext4_ext_rm_idx(handle_t *handle, struct inode *inode, break; err = ext4_ext_get_access(handle, inode, path + k); if (err) - break; + goto clean; path[k].p_idx->ei_block = path[k + 1].p_idx->ei_block; err = ext4_ext_dirty(handle, inode, path + k); if (err) - break; + goto clean; } + return 0; + +clean: + /* + * The path[k].p_bh is either unmodified or with no verified bit + * set (see ext4_ext_get_access()). So just clear the verified bit + * of the successfully modified extents buffers, which will force + * these extents to be checked to avoid using inconsistent data. + */ + while (++k < depth) + clear_buffer_verified(path[k].p_bh); + return err; } |