From patchwork Thu Nov 10 14:13:42 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: ChenXiaoSong X-Patchwork-Id: 13038833 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B9A78C4332F for ; Thu, 10 Nov 2022 13:59:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231283AbiKJN7R (ORCPT ); Thu, 10 Nov 2022 08:59:17 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40608 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231308AbiKJN7O (ORCPT ); Thu, 10 Nov 2022 08:59:14 -0500 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 10C3F19C19; Thu, 10 Nov 2022 05:59:13 -0800 (PST) Received: from dggemv704-chm.china.huawei.com (unknown [172.30.72.57]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4N7Njc2LD6zRnvL; Thu, 10 Nov 2022 21:59:00 +0800 (CST) Received: from kwepemm600015.china.huawei.com (7.193.23.52) by dggemv704-chm.china.huawei.com (10.3.19.47) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Thu, 10 Nov 2022 21:59:11 +0800 Received: from huawei.com (10.175.101.6) by kwepemm600015.china.huawei.com (7.193.23.52) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Thu, 10 Nov 2022 21:59:10 +0800 From: ChenXiaoSong To: , , CC: , , , , Subject: [PATCH] btrfs: qgroup: fix sleep from invalid context bug in update_qgroup_limit_item() Date: Thu, 10 Nov 2022 22:13:42 +0800 Message-ID: <20221110141342.2129475-1-chenxiaosong2@huawei.com> X-Mailer: git-send-email 2.31.1 MIME-Version: 1.0 X-Originating-IP: [10.175.101.6] X-ClientProxiedBy: dggems701-chm.china.huawei.com (10.3.19.178) To kwepemm600015.china.huawei.com (7.193.23.52) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org Syzkaller reported BUG as follows: BUG: sleeping function called from invalid context at include/linux/sched/mm.h:274 Call Trace: dump_stack_lvl+0xcd/0x134 __might_resched.cold+0x222/0x26b kmem_cache_alloc+0x2e7/0x3c0 update_qgroup_limit_item+0xe1/0x390 btrfs_qgroup_inherit+0x147b/0x1ee0 create_subvol+0x4eb/0x1710 btrfs_mksubvol+0xfe5/0x13f0 __btrfs_ioctl_snap_create+0x2b0/0x430 btrfs_ioctl_snap_create_v2+0x25a/0x520 btrfs_ioctl+0x2a1c/0x5ce0 __x64_sys_ioctl+0x193/0x200 do_syscall_64+0x35/0x80 Fix this by introducing __update_qgroup_limit_item() helper, allocate memory outside of the spin lock. Signed-off-by: ChenXiaoSong --- fs/btrfs/qgroup.c | 35 ++++++++++++++++++++++++++--------- 1 file changed, 26 insertions(+), 9 deletions(-) diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c index 9334c3157c22..99a61cc04b68 100644 --- a/fs/btrfs/qgroup.c +++ b/fs/btrfs/qgroup.c @@ -768,11 +768,11 @@ static int del_qgroup_item(struct btrfs_trans_handle *trans, u64 qgroupid) return ret; } -static int update_qgroup_limit_item(struct btrfs_trans_handle *trans, - struct btrfs_qgroup *qgroup) +static int __update_qgroup_limit_item(struct btrfs_trans_handle *trans, + struct btrfs_qgroup *qgroup, + struct btrfs_path *path) { struct btrfs_root *quota_root = trans->fs_info->quota_root; - struct btrfs_path *path; struct btrfs_key key; struct extent_buffer *l; struct btrfs_qgroup_limit_item *qgroup_limit; @@ -783,10 +783,6 @@ static int update_qgroup_limit_item(struct btrfs_trans_handle *trans, key.type = BTRFS_QGROUP_LIMIT_KEY; key.offset = qgroup->qgroupid; - path = btrfs_alloc_path(); - if (!path) - return -ENOMEM; - ret = btrfs_search_slot(trans, quota_root, &key, path, 0, 1); if (ret > 0) ret = -ENOENT; @@ -806,6 +802,21 @@ static int update_qgroup_limit_item(struct btrfs_trans_handle *trans, btrfs_mark_buffer_dirty(l); out: + return ret; +} + +static int update_qgroup_limit_item(struct btrfs_trans_handle *trans, + struct btrfs_qgroup *qgroup) +{ + struct btrfs_path *path; + int ret; + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + ret = __update_qgroup_limit_item(trans, qgroup, path); + btrfs_free_path(path); return ret; } @@ -2860,6 +2871,7 @@ int btrfs_qgroup_inherit(struct btrfs_trans_handle *trans, u64 srcid, bool need_rescan = false; u32 level_size = 0; u64 nums; + struct btrfs_path *path; /* * There are only two callers of this function. @@ -2935,6 +2947,11 @@ int btrfs_qgroup_inherit(struct btrfs_trans_handle *trans, u64 srcid, ret = 0; } + path = btrfs_alloc_path(); + if (!path) { + ret = -ENOMEM; + goto out; + } spin_lock(&fs_info->qgroup_lock); @@ -2950,8 +2967,7 @@ int btrfs_qgroup_inherit(struct btrfs_trans_handle *trans, u64 srcid, dstgroup->max_excl = inherit->lim.max_excl; dstgroup->rsv_rfer = inherit->lim.rsv_rfer; dstgroup->rsv_excl = inherit->lim.rsv_excl; - - ret = update_qgroup_limit_item(trans, dstgroup); + ret = __update_qgroup_limit_item(trans, dstgroup, path); if (ret) { qgroup_mark_inconsistent(fs_info); btrfs_info(fs_info, @@ -3053,6 +3069,7 @@ int btrfs_qgroup_inherit(struct btrfs_trans_handle *trans, u64 srcid, unlock: spin_unlock(&fs_info->qgroup_lock); + btrfs_free_path(path); if (!ret) ret = btrfs_sysfs_add_one_qgroup(fs_info, dstgroup); out: