diff options
Diffstat (limited to 'fs/fuse')
| -rw-r--r-- | fs/fuse/fuse_i.h | 1 | ||||
| -rw-r--r-- | fs/fuse/inode.c | 44 |
2 files changed, 22 insertions, 23 deletions
diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h index 07829ce78695..a78480933ebe 100644 --- a/fs/fuse/fuse_i.h +++ b/fs/fuse/fuse_i.h @@ -489,6 +489,7 @@ struct fuse_dev { struct fuse_fs_context { int fd; + struct file *file; unsigned int rootmode; kuid_t user_id; kgid_t group_id; diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c index 54379a0c86d3..3d64a68c52f7 100644 --- a/fs/fuse/inode.c +++ b/fs/fuse/inode.c @@ -1509,38 +1509,33 @@ EXPORT_SYMBOL_GPL(fuse_fill_super_common); static int fuse_fill_super(struct super_block *sb, struct fs_context *fsc) { struct fuse_fs_context *ctx = fsc->fs_private; - struct file *file; int err; struct fuse_conn *fc; struct fuse_mount *fm; - if (!ctx->fd_present || !ctx->rootmode_present || + if (!ctx->file || !ctx->rootmode_present || !ctx->user_id_present || !ctx->group_id_present) return -EINVAL; - err = -EINVAL; - file = fget(ctx->fd); - if (!file) - goto err; - /* * Require mount to happen from the same user namespace which * opened /dev/fuse to prevent potential attacks. */ - if ((file->f_op != &fuse_dev_operations) || - (file->f_cred->user_ns != sb->s_user_ns)) - goto err_fput; - ctx->fudptr = &file->private_data; + err = -EINVAL; + if ((ctx->file->f_op != &fuse_dev_operations) || + (ctx->file->f_cred->user_ns != sb->s_user_ns)) + goto err; + ctx->fudptr = &ctx->file->private_data; fc = kmalloc(sizeof(*fc), GFP_KERNEL); err = -ENOMEM; if (!fc) - goto err_fput; + goto err; fm = kzalloc(sizeof(*fm), GFP_KERNEL); if (!fm) { kfree(fc); - goto err_fput; + goto err; } fuse_conn_init(fc, fm, sb->s_user_ns, &fuse_dev_fiq_ops, NULL); @@ -1551,12 +1546,8 @@ static int fuse_fill_super(struct super_block *sb, struct fs_context *fsc) err = fuse_fill_super_common(sb, ctx); if (err) goto err_put_conn; - /* - * atomic_dec_and_test() in fput() provides the necessary - * memory barrier for file->private_data to be visible on all - * CPUs after this - */ - fput(file); + /* file->private_data shall be visible on all CPUs after this */ + smp_mb(); fuse_send_init(get_fuse_mount_super(sb)); return 0; @@ -1564,8 +1555,6 @@ static int fuse_fill_super(struct super_block *sb, struct fs_context *fsc) fuse_conn_put(fc); kfree(fm); sb->s_fs_info = NULL; - err_fput: - fput(file); err: return err; } @@ -1573,12 +1562,21 @@ static int fuse_fill_super(struct super_block *sb, struct fs_context *fsc) static int fuse_get_tree(struct fs_context *fsc) { struct fuse_fs_context *ctx = fsc->fs_private; + int err; + + if (ctx->fd_present) + ctx->file = fget(ctx->fd); if (IS_ENABLED(CONFIG_BLOCK) && ctx->is_bdev) { - return get_tree_bdev(fsc, fuse_fill_super); + err = get_tree_bdev(fsc, fuse_fill_super); + goto out_fput; } - return get_tree_nodev(fsc, fuse_fill_super); + err = get_tree_nodev(fsc, fuse_fill_super); +out_fput: + if (ctx->file) + fput(ctx->file); + return err; } static const struct fs_context_operations fuse_context_ops = { |