diff options
| -rw-r--r-- | fs/fuse/inode.c | 38 |
1 files changed, 37 insertions, 1 deletions
diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c index 3d64a68c52f7..a3e7fb484938 100644 --- a/fs/fuse/inode.c +++ b/fs/fuse/inode.c @@ -1559,9 +1559,26 @@ static int fuse_fill_super(struct super_block *sb, struct fs_context *fsc) return err; } +/* + * This is the path where user supplied an already initialized fuse dev. In + * this case never create a new super if the old one is gone. + */ +static int fuse_set_no_super(struct super_block *sb, struct fs_context *fsc) +{ + return -ENOTCONN; +} + +static int fuse_test_super(struct super_block *sb, struct fs_context *fsc) +{ + + return fsc->sget_key == get_fuse_conn_super(sb); +} + static int fuse_get_tree(struct fs_context *fsc) { struct fuse_fs_context *ctx = fsc->fs_private; + struct fuse_dev *fud; + struct super_block *sb; int err; if (ctx->fd_present) @@ -1571,8 +1588,27 @@ static int fuse_get_tree(struct fs_context *fsc) err = get_tree_bdev(fsc, fuse_fill_super); goto out_fput; } + /* + * While block dev mount can be initialized with a dummy device fd + * (found by device name), normal fuse mounts can't + */ + if (!ctx->file) + return -EINVAL; - err = get_tree_nodev(fsc, fuse_fill_super); + /* + * Allow creating a fuse mount with an already initialized fuse + * connection + */ + fud = READ_ONCE(ctx->file->private_data); + if (ctx->file->f_op == &fuse_dev_operations && fud) { + fsc->sget_key = fud->fc; + sb = sget_fc(fsc, fuse_test_super, fuse_set_no_super); + err = PTR_ERR_OR_ZERO(sb); + if (!IS_ERR(sb)) + fsc->root = dget(sb->s_root); + } else { + err = get_tree_nodev(fsc, fuse_fill_super); + } out_fput: if (ctx->file) fput(ctx->file); |