From 5157da2ca42cbeca01709e29ce7b797cffed2432 Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Tue, 19 May 2020 14:50:37 +0200 Subject: fuse: always allow query of st_dev Fuse mounts without "allow_other" are off-limits to all non-owners. Yet it makes sense to allow querying st_dev on the root, since this value is provided by the kernel, not the userspace filesystem. Allow statx(2) with a zero request mask to succeed on a fuse mounts for all users. Reported-by: Nikolaus Rath Signed-off-by: Miklos Szeredi --- fs/fuse/dir.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) (limited to 'fs/fuse/dir.c') diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c index de1e2fde60bd..26f028bc760b 100644 --- a/fs/fuse/dir.c +++ b/fs/fuse/dir.c @@ -1689,8 +1689,18 @@ static int fuse_getattr(const struct path *path, struct kstat *stat, struct inode *inode = d_inode(path->dentry); struct fuse_conn *fc = get_fuse_conn(inode); - if (!fuse_allow_current_process(fc)) + if (!fuse_allow_current_process(fc)) { + if (!request_mask) { + /* + * If user explicitly requested *nothing* then don't + * error out, but return st_dev only. + */ + stat->result_mask = 0; + stat->dev = inode->i_sb->s_dev; + return 0; + } return -EACCES; + } return fuse_update_get_attr(inode, NULL, stat, request_mask, flags); } -- cgit v1.2.3-59-g8ed1b