tmpfs: generate random sb->s_uuid

This is used by overlayfs to encode intrasystem unique file handles.

Suggested-by: Miklos Szeredi <mszeredi@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
This commit is contained in:
Amir Goldstein 2017-05-18 15:29:33 +03:00 committed by Christoph Hellwig
parent bf47643389
commit 2b4db79618

View File

@ -75,6 +75,7 @@ static struct vfsmount *shm_mnt;
#include <uapi/linux/memfd.h>
#include <linux/userfaultfd_k.h>
#include <linux/rmap.h>
#include <linux/uuid.h>
#include <linux/uaccess.h>
#include <asm/pgtable.h>
@ -3761,6 +3762,7 @@ int shmem_fill_super(struct super_block *sb, void *data, int silent)
#ifdef CONFIG_TMPFS_POSIX_ACL
sb->s_flags |= MS_POSIXACL;
#endif
uuid_gen(&sb->s_uuid);
inode = shmem_get_inode(sb, NULL, S_IFDIR | sbinfo->mode, 0, VM_NORESERVE);
if (!inode)