From nobody Sat Sep 26 10:04:58 2026 Received: from mailgw.kylinos.cn (mailgw.kylinos.cn [124.126.103.232]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2E7453EFD22; Wed, 2 Sep 2026 10:19:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=124.126.103.232 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788344360; cv=none; b=TfcdZOowoWidT/KK4MAY/1MgdWD4C530gIvvQDGrZmmb72xvptm0GIlo9TChQDRoYP8nL6wUIzx8/QO4T0EH0HC2qMDc7O+Eet7RAF0NSXwZJzsCKJ6fiAhxIMB0uEZVfQiFK6cEpm0hGJhDM+rFHMpRQU0wwjBCro/KzaPtTXY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788344360; c=relaxed/simple; bh=0uXLbFCjKkSc5bdGWkdSocxRnPS4EEyfA57szxibfjw=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=fJAhchA7mqQB93U+np7pQt/xZYsHWra7iCFc79g8tyWIvhPSEfKjGpHeluS/kLPnj5W3zT138nDqJLus0gQ6cE1dszA20zxz6wMVJYJrwPyVRWDX+esTia0AyesMbceKtMbcA/DhNg+mjtjTodVe1SRlCe2fD3i5D0NZvsxt124= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kylinos.cn; spf=pass smtp.mailfrom=kylinos.cn; arc=none smtp.client-ip=124.126.103.232 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kylinos.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=kylinos.cn X-UUID: b9ed5c00a6b711f19a56ed5b684f684d-20260902 X-CTIC-Tags: HR_CC_COUNT, HR_CC_DOMAIN_COUNT, HR_CC_NAME, HR_CC_NO_NAME, HR_CTE_8B HR_CTT_MISS, HR_DATE_H, HR_DATE_WKD, HR_DATE_ZONE, HR_FROM_NAME HR_SJ_LANG, HR_SJ_LEN, HR_SJ_LETTER, HR_SJ_NOR_SYM, HR_SJ_PHRASE HR_SJ_PHRASE_LEN, HR_SJ_WS, HR_TO_COUNT, HR_TO_DOMAIN_COUNT, HR_TO_NAME HR_TO_NO_NAME, IP_TRUSTED, SRC_TRUSTED, DN_TRUSTED, SA_TRUSTED SA_EXISTED, SN_EXISTED, SPF_NOPASS, DKIM_NOPASS, DMARC_NOPASS CIE_BAD, CIE_GOOD, CIE_GOOD_SPF, GTI_FG_BS, GTI_RG_INFO GTI_C_BU, AMN_GOOD, ABX_MISS_RDNS X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.3.19,REQID:9ebfbd50-ea65-42a1-a090-8e18eb9596ca,IP:10, URL:0,TC:0,Content:0,EDM:25,RT:0,SF:0,FILE:0,BULK:0,RULE:Release_Ham,ACTIO N:release,TS:35 X-CID-INFO: VERSION:1.3.19,REQID:9ebfbd50-ea65-42a1-a090-8e18eb9596ca,IP:10,UR L:0,TC:0,Content:0,EDM:25,RT:0,SF:0,FILE:0,BULK:0,RULE:Release_Ham,ACTION: release,TS:35 X-CID-META: VersionHash:7db8b62,CLOUDID:c79026a429cb39097d0fb0fc4418a6ac,BulkI D:260902181910FXD04WUY,BulkQuantity:0,SF:10|38|66|78|102|127|865|898,TC:ni l,Content:0|15|50,EDM:5,IP:-2,URL:0,File:nil,RT:nil,Bulk:nil,QS:nil,BEC:ni l,COL:0,OSI:0,OSA:0,AV:0,LES:1,SPR:NO,DKR:0,DKP:0,BRR:0,BRE:0,ARC:0 X-CID-BVR: 2,SSN|SDN X-CID-BAS: 2,SSN|SDN,0,_ X-CID-FACTOR: TF_CID_SPAM_SNR X-CID-RHF: D41D8CD98F00B204E9800998ECF8427E X-UUID: b9ed5c00a6b711f19a56ed5b684f684d-20260902 X-User: sunshaojie@kylinos.cn Received: from sunshaojie-pc [(223.70.159.239)] by mailgw.kylinos.cn (envelope-from ) (Generic MTA with TLSv1.3 TLS_AES_256_GCM_SHA384 256/256) with ESMTP id 1710416012; Wed, 02 Sep 2026 18:19:05 +0800 From: Shaojie Sun To: Tejun Heo , Johannes Weiner , mkoutny@suse.com Cc: cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, Shaojie Sun Subject: [PATCH] cgroup: namespace: replace BUG_ON() in copy_cgroup_ns() with WARN_ON_ONCE() Date: Wed, 2 Sep 2026 18:18:56 +0800 Message-ID: <20260902101856.225493-1-sunshaojie@kylinos.cn> X-Mailer: git-send-email 2.50.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" copy_cgroup_ns() uses BUG_ON() to guard against a NULL old_ns. The condition cannot currently be triggered by any caller, and the sole caller, create_new_namespaces(), already checks the return value with IS_ERR() and unwinds correctly. Replace the BUG_ON() with WARN_ON_ONCE() and return -EINVAL instead, consistent with the policy of not killing the whole machine for a recoverable programming error. Signed-off-by: Shaojie Sun --- kernel/cgroup/namespace.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/cgroup/namespace.c b/kernel/cgroup/namespace.c index ea4ee13936be..13930955c254 100644 --- a/kernel/cgroup/namespace.c +++ b/kernel/cgroup/namespace.c @@ -53,7 +53,8 @@ struct cgroup_namespace *copy_cgroup_ns(u64 flags, struct ucounts *ucounts; struct css_set *cset; =20 - BUG_ON(!old_ns); + if (WARN_ON_ONCE(!old_ns)) + return ERR_PTR(-EINVAL); =20 if (!(flags & CLONE_NEWCGROUP)) { get_cgroup_ns(old_ns); --=20 2.50.1