From nobody Sat Jun 13 03:33:48 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 3FDAE33B97A; Mon, 11 May 2026 06:08:22 +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=1778479706; cv=none; b=L2Wsw9HlZ19N8XahonCw3rw/qjXp2Yep4TuK/G/Il0QmduMoS8o66O+fClRW0pJMTDqhWVeTxUSzXXbdWwl0GWdHEdmCoO4UIW2MyyXdckIofLHoRzeucVh1oRG2539IdsRP5RmgJ6WBsUhawk5Nj2DLV+OFBKVH/uTHykriR0g= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778479706; c=relaxed/simple; bh=Kq9+irIQ+Aybd2yCzFk8K/Gk+K5vfmjQpmy4GsHmGy0=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=PghddgEKDxFBhtYXYGwzFgJUbJs0vBZyJslmBFqlty7YzUJegiMF8m8jmTPmUf9ElglubrHTYP70JIS0u++8upJEiY29eCLbsxuEjHNZsinwWdHF6vdJG/yOKrPgQ/qxM+eur6foBGqfULEjaOaLKvAQ4DY4jS8/tyukIiaF3XA= 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: cdd4ab544cff11f1aa26b74ffac11d73-20260511 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_NO_NAME IP_TRUSTED, SRC_TRUSTED, DN_TRUSTED, SA_TRUSTED, SA_EXISTED SN_TRUSTED, 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:1.3.12,REQID:af430201-01df-4919-835e-98a5072227c1,IP:10, URL:0,TC:0,Content:0,EDM:0,RT:0,SF:-5,FILE:0,BULK:0,RULE:Release_Ham,ACTIO N:release,TS:5 X-CID-INFO: VERSION:1.3.12,REQID:af430201-01df-4919-835e-98a5072227c1,IP:10,UR L:0,TC:0,Content:0,EDM:0,RT:0,SF:-5,FILE:0,BULK:0,RULE:Release_Ham,ACTION: release,TS:5 X-CID-META: VersionHash:e7bac3a,CLOUDID:1904734c7ddded50cbbd212d5c935b79,BulkI D:2605111408189JNWAS71,BulkQuantity:0,Recheck:0,SF:17|19|38|66|78|102|127| 850|898,TC:nil,Content:0|15|50,EDM:-3,IP:-2,URL:0,File:nil,RT:nil,Bulk:nil ,QS:nil,BEC:nil,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,TF_CID_SPAM_FAS,TF_CID_SPAM_FSD X-CID-RHF: D41D8CD98F00B204E9800998ECF8427E X-UUID: cdd4ab544cff11f1aa26b74ffac11d73-20260511 X-User: lihongfu@kylinos.cn Received: from localhost.localdomain [(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 768878464; Mon, 11 May 2026 14:08:17 +0800 From: Hongfu Li To: tj@kernel.org, hannes@cmpxchg.org, mkoutny@suse.com, shuah@kernel.org, jthoughton@google.com, seanjc@google.com, zhangguopeng@kylinos.cn Cc: cgroups@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, Hongfu Li Subject: [PATCH] selftests/cgroup: Add NULL check after malloc in cgroup_util.c Date: Mon, 11 May 2026 14:08:53 +0800 Message-Id: <20260511060853.1873161-1-lihongfu@kylinos.cn> X-Mailer: git-send-email 2.25.1 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" Add NULL checks after malloc() in three helper functions to prevent NULL pointer dereference on memory allocation failure. - cg_name() - cg_name_indexed() - cg_control() These functions allocate memory with malloc() but previously called snprintf() unconditionally, which would trigger undefined behavior if allocation fails. Signed-off-by: Hongfu Li Reviewed-by: Vishal Moola --- tools/testing/selftests/cgroup/lib/cgroup_util.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/tools/testing/selftests/cgroup/lib/cgroup_util.c b/tools/testi= ng/selftests/cgroup/lib/cgroup_util.c index 6a7295347e90..0c5e6d4bbc3a 100644 --- a/tools/testing/selftests/cgroup/lib/cgroup_util.c +++ b/tools/testing/selftests/cgroup/lib/cgroup_util.c @@ -59,7 +59,8 @@ char *cg_name(const char *root, const char *name) size_t len =3D strlen(root) + strlen(name) + 2; char *ret =3D malloc(len); =20 - snprintf(ret, len, "%s/%s", root, name); + if (ret) + snprintf(ret, len, "%s/%s", root, name); =20 return ret; } @@ -69,7 +70,8 @@ char *cg_name_indexed(const char *root, const char *name,= int index) size_t len =3D strlen(root) + strlen(name) + 10; char *ret =3D malloc(len); =20 - snprintf(ret, len, "%s/%s_%d", root, name, index); + if (ret) + snprintf(ret, len, "%s/%s_%d", root, name, index); =20 return ret; } @@ -79,7 +81,8 @@ char *cg_control(const char *cgroup, const char *control) size_t len =3D strlen(cgroup) + strlen(control) + 2; char *ret =3D malloc(len); =20 - snprintf(ret, len, "%s/%s", cgroup, control); + if (ret) + snprintf(ret, len, "%s/%s", cgroup, control); =20 return ret; } --=20 2.25.1