6.7-stable review patch. If anyone has any objections, please let me know.
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From: Al Viro viro@zeniv.linux.org.uk
commit bbe6a7c899e7f265c5a6d01a178336a405e98ed6 upstream.
make it use user_path_locked_at() to get the normal directory protection for modifications, as well as stable ->d_parent and ->d_name in victim
Signed-off-by: Al Viro viro@zeniv.linux.org.uk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/bcachefs/fs-ioctl.c | 31 +++++++++++++++++-------------- 1 file changed, 17 insertions(+), 14 deletions(-)
--- a/fs/bcachefs/fs-ioctl.c +++ b/fs/bcachefs/fs-ioctl.c @@ -451,33 +451,36 @@ static long bch2_ioctl_subvolume_create( static long bch2_ioctl_subvolume_destroy(struct bch_fs *c, struct file *filp, struct bch_ioctl_subvolume arg) { + const char __user *name = (void __user *)(unsigned long)arg.dst_ptr; struct path path; struct inode *dir; + struct dentry *victim; int ret = 0;
if (arg.flags) return -EINVAL;
- ret = user_path_at(arg.dirfd, - (const char __user *)(unsigned long)arg.dst_ptr, - LOOKUP_FOLLOW, &path); - if (ret) - return ret; + victim = user_path_locked_at(arg.dirfd, name, &path); + if (IS_ERR(victim)) + return PTR_ERR(victim);
- if (path.dentry->d_sb->s_fs_info != c) { + if (victim->d_sb->s_fs_info != c) { ret = -EXDEV; goto err; } - - dir = path.dentry->d_parent->d_inode; - - ret = __bch2_unlink(dir, path.dentry, true); - if (ret) + if (!d_is_positive(victim)) { + ret = -ENOENT; goto err; - - fsnotify_rmdir(dir, path.dentry); - d_delete(path.dentry); + } + dir = d_inode(path.dentry); + ret = __bch2_unlink(dir, victim, true); + if (!ret) { + fsnotify_rmdir(dir, victim); + d_delete(victim); + } + inode_unlock(dir); err: + dput(victim); path_put(&path); return ret; }