[PATCH v1 1/2] ext4: find old entry again if failed to rename whiteout
From: "zhangyi (F)" <yi.zhang@huawei.com>
Date: 2021-03-03 15:38:32
Subsystem:
ext4 file system, filesystems (vfs and infrastructure), the rest · Maintainers:
"Theodore Ts'o", Alexander Viro, Christian Brauner, Linus Torvalds
If we failed to add new entry on rename whiteout, we cannot reset the
old->de entry directly, because the old->de could have moved from under
us during make indexed dir. So find the old entry again before reset is
needed, otherwise it may corrupt the filesystem as below.
/dev/sda: Entry '00000001' in ??? (12) has deleted/unused inode 15. CLEARED.
/dev/sda: Unattached inode 75
/dev/sda: UNEXPECTED INCONSISTENCY; RUN fsck MANUALLY.
Fixes: 6b4b8e6b4ad ("ext4: fix bug for rename with RENAME_WHITEOUT")
Cc: stable@vger.kernel.org
Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
---
fs/ext4/namei.c | 29 +++++++++++++++++++++++++++--
1 file changed, 27 insertions(+), 2 deletions(-)
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index cf652ba3e74d..17d9400563fa 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c@@ -3602,6 +3602,31 @@ static int ext4_setent(handle_t *handle, struct ext4_renament *ent, return retval; } +static void ext4_resetent(handle_t *handle, struct ext4_renament *ent, + unsigned ino, unsigned file_type) +{ + struct ext4_renament old = *ent; + int retval = 0; + + /* + * old->de could have moved from under us during make indexed dir, + * so the old->de may no longer valid and need to find it again + * before reset old inode info. + */ + old.bh = ext4_find_entry(old.dir, &old.dentry->d_name, &old.de, NULL); + if (IS_ERR(old.bh)) + retval = PTR_ERR(old.bh); + if (!old.bh) + retval = -ENOENT; + if (retval) { + ext4_std_error(old.dir->i_sb, retval); + return; + } + + ext4_setent(handle, &old, ino, file_type); + brelse(old.bh); +} + static int ext4_find_delete_entry(handle_t *handle, struct inode *dir, const struct qstr *d_name) {
@@ -3924,8 +3949,8 @@ static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry, end_rename: if (whiteout) { if (retval) { - ext4_setent(handle, &old, - old.inode->i_ino, old_file_type); + ext4_resetent(handle, &old, + old.inode->i_ino, old_file_type); drop_nlink(whiteout); } unlock_new_inode(whiteout);
--
2.25.4