Searched hist:"5474 bf40" (Results 1 – 1 of 1) sorted by relevance
/openbmc/linux/fs/btrfs/ |
H A D | ioctl.c | 5474bf40 Tue Jul 27 05:48:51 CDT 2021 Christian Brauner <christian.brauner@ubuntu.com> btrfs: check whether fsgid/fsuid are mapped during subvolume creation
When a new subvolume is created btrfs currently doesn't check whether the fsgid/fsuid of the caller actually have a mapping in the user namespace attached to the filesystem. The VFS always checks this to make sure that the caller's fsgid/fsuid can be represented on-disk. This is most relevant for filesystems that can be mounted inside user namespaces but it is in general a good hardening measure to prevent unrepresentable gid/uid from being written to disk.
Since we want to support idmapped mounts for btrfs ioctls to create subvolumes in follow-up patches this becomes important since we want to make sure the fsgid/fsuid of the caller as mapped according to the idmapped mount can be represented on-disk. Simply add the missing fsuidgid_has_mapping() line from the VFS may_create() version to btrfs_may_create().
Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
|