diff --git a/fs/namespace.c b/fs/namespace.c index 156771f5745a227127e0788b6c6a4bfad7cfea32..0354cb6ac2d37b357bd217f1a42c8b78207510aa 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -2479,29 +2479,6 @@ static int do_move_mount(struct path *path, const char *old_name) return err; } -static struct vfsmount *fs_set_subtype(struct vfsmount *mnt, const char *fstype) -{ - int err; - const char *subtype = strchr(fstype, '.'); - if (subtype) { - subtype++; - err = -EINVAL; - if (!subtype[0]) - goto err; - } else - subtype = ""; - - mnt->mnt_sb->s_subtype = kstrdup(subtype, GFP_KERNEL); - err = -ENOMEM; - if (!mnt->mnt_sb->s_subtype) - goto err; - return mnt; - - err: - mntput(mnt); - return ERR_PTR(err); -} - /* * add a mount into a namespace's mount tree */ @@ -2557,7 +2534,9 @@ static int do_new_mount(struct path *path, const char *fstype, int sb_flags, { struct file_system_type *type; struct vfsmount *mnt; - int err; + struct fs_context *fc; + const char *subtype = NULL; + int err = 0; if (!fstype) return -EINVAL; @@ -2566,23 +2545,59 @@ static int do_new_mount(struct path *path, const char *fstype, int sb_flags, if (!type) return -ENODEV; - mnt = vfs_kern_mount(type, sb_flags, name, data); - if (!IS_ERR(mnt) && (type->fs_flags & FS_HAS_SUBTYPE) && - !mnt->mnt_sb->s_subtype) - mnt = fs_set_subtype(mnt, fstype); + if (type->fs_flags & FS_HAS_SUBTYPE) { + subtype = strchr(fstype, '.'); + if (subtype) { + subtype++; + if (!*subtype) { + put_filesystem(type); + return -EINVAL; + } + } else { + subtype = ""; + } + } + fc = fs_context_for_mount(type, sb_flags); put_filesystem(type); - if (IS_ERR(mnt)) - return PTR_ERR(mnt); + if (IS_ERR(fc)) + return PTR_ERR(fc); + + if (subtype) { + fc->subtype = kstrdup(subtype, GFP_KERNEL); + if (!fc->subtype) + err = -ENOMEM; + } + if (!err && name) { + fc->source = kstrdup(name, GFP_KERNEL); + if (!fc->source) + err = -ENOMEM; + } + if (!err) + err = parse_monolithic_mount_data(fc, data); + if (!err) + err = vfs_get_tree(fc); + if (err) + goto out; + + up_write(&fc->root->d_sb->s_umount); + mnt = vfs_create_mount(fc); + if (IS_ERR(mnt)) { + err = PTR_ERR(mnt); + goto out; + } if (mount_too_revealing(mnt, &mnt_flags)) { mntput(mnt); - return -EPERM; + err = -EPERM; + goto out; } err = do_add_mount(real_mount(mnt), path, mnt_flags); if (err) mntput(mnt); +out: + put_fs_context(fc); return err; } diff --git a/fs/super.c b/fs/super.c index fc3887277ad19983d0a3f7380d7c2827fddfbca2..b91b6df05b67c347c2e7d5dbd890bb3b0e922b7c 100644 --- a/fs/super.c +++ b/fs/super.c @@ -1262,6 +1262,11 @@ int vfs_get_tree(struct fs_context *fc) sb = fc->root->d_sb; WARN_ON(!sb->s_bdi); + if (fc->subtype && !sb->s_subtype) { + sb->s_subtype = fc->subtype; + fc->subtype = NULL; + } + /* * Write barrier is for super_cache_count(). We place it before setting * SB_BORN as the data dependency between the two functions is the diff --git a/include/linux/fs.h b/include/linux/fs.h index 811c77743dad2870282e6c3c85e8f238f8643767..36fff12ab8904f9eaec8b1f8164eb0eaddf3c37f 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1447,7 +1447,7 @@ struct super_block { * Filesystem subtype. If non-empty the filesystem type field * in /proc/mounts will be "type.subtype" */ - char *s_subtype; + const char *s_subtype; const struct dentry_operations *s_d_op; /* default d_op for dentries */