diff options
| author | Al Viro <viro@zeniv.linux.org.uk> | 2023-10-17 14:55:42 -0400 |
|---|---|---|
| committer | Al Viro <viro@zeniv.linux.org.uk> | 2023-11-25 02:53:20 -0500 |
| commit | 40dbd071f4b19d9630353c3cd45c2d6adb6799d4 (patch) | |
| tree | c0b9a64213f125315b57e67882ddbc32c08914dc | |
| parent | 7307b73fa5a82661808b5541972176c344978789 (diff) | |
ext4: don't access the source subdirectory content on same-directory rename
We can't really afford locking the source on same-directory rename;
currently vfs_rename() tries to do that, but it will have to be changed.
The logics in ext4 is lazy and goes looking for ".." in source even in
same-directory case. It's not hard to get rid of that, leaving that
behaviour only for cross-directory case; that VFS can get locks safely
(and will keep doing that after the coming changes).
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| -rw-r--r-- | fs/ext4/namei.c | 21 |
1 files changed, 13 insertions, 8 deletions
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c index d252935f9c8a..467ba47a691c 100644 --- a/fs/ext4/namei.c +++ b/fs/ext4/namei.c @@ -3591,10 +3591,14 @@ struct ext4_renament { int dir_inlined; }; -static int ext4_rename_dir_prepare(handle_t *handle, struct ext4_renament *ent) +static int ext4_rename_dir_prepare(handle_t *handle, struct ext4_renament *ent, bool is_cross) { int retval; + ent->is_dir = true; + if (!is_cross) + return 0; + ent->dir_bh = ext4_get_first_dir_block(handle, ent->inode, &retval, &ent->parent_de, &ent->dir_inlined); @@ -3612,6 +3616,9 @@ static int ext4_rename_dir_finish(handle_t *handle, struct ext4_renament *ent, { int retval; + if (!ent->dir_bh) + return 0; + ent->parent_de->inode = cpu_to_le32(dir_ino); BUFFER_TRACE(ent->dir_bh, "call ext4_handle_dirty_metadata"); if (!ent->dir_inlined) { @@ -3900,7 +3907,7 @@ static int ext4_rename(struct mnt_idmap *idmap, struct inode *old_dir, if (new.dir != old.dir && EXT4_DIR_LINK_MAX(new.dir)) goto end_rename; } - retval = ext4_rename_dir_prepare(handle, &old); + retval = ext4_rename_dir_prepare(handle, &old, new.dir != old.dir); if (retval) goto end_rename; } @@ -3964,7 +3971,7 @@ static int ext4_rename(struct mnt_idmap *idmap, struct inode *old_dir, } inode_set_mtime_to_ts(old.dir, inode_set_ctime_current(old.dir)); ext4_update_dx_flag(old.dir); - if (old.dir_bh) { + if (old.is_dir) { retval = ext4_rename_dir_finish(handle, &old, new.dir->i_ino); if (retval) goto end_rename; @@ -3987,7 +3994,7 @@ static int ext4_rename(struct mnt_idmap *idmap, struct inode *old_dir, if (unlikely(retval)) goto end_rename; - if (S_ISDIR(old.inode->i_mode)) { + if (old.is_dir) { /* * We disable fast commits here that's because the * replay code is not yet capable of changing dot dot @@ -4114,14 +4121,12 @@ static int ext4_cross_rename(struct inode *old_dir, struct dentry *old_dentry, ext4_handle_sync(handle); if (S_ISDIR(old.inode->i_mode)) { - old.is_dir = true; - retval = ext4_rename_dir_prepare(handle, &old); + retval = ext4_rename_dir_prepare(handle, &old, new.dir != old.dir); if (retval) goto end_rename; } if (S_ISDIR(new.inode->i_mode)) { - new.is_dir = true; - retval = ext4_rename_dir_prepare(handle, &new); + retval = ext4_rename_dir_prepare(handle, &new, new.dir != old.dir); if (retval) goto end_rename; } |