From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp-fw-52005.amazon.com (smtp-fw-52005.amazon.com [52.119.213.156]) (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 6A44A282FA for ; Thu, 13 Mar 2025 15:23:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=52.119.213.156 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741879400; cv=none; b=OBbwsULcO532yeEHNSSYav1UR0QAzfm6Yr5RsOSUWu29jTGJMII7f57KEBMopEFiuQUFa16jVUZ4NAiCVK/aWxLvfndE3XFtoQNUrwCLBtix8dZDutgzKYPkWktaQcBqcpIIHKFDfgIcuNdJ1L9nYzXlglG3oaG5h3ehjJgia8E= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741879400; c=relaxed/simple; bh=lXg5w4GFh0c12onPd3EVbRDifrFN8rRiMVvGExc6mJs=; h=From:To:CC:Subject:Date:Message-ID:MIME-Version:Content-Type; b=XyNKKzcT8MUx6oDq0bkoc3bVL4oIk5g/FuLFmBRJ+4Ab/GYmb8UKSX1BHSZgiAKBe2AAqqWxOA4jnYF44Fme2CMN3tKew2wP5TEFmzzDAt2X4+nizofvZ+ziKeL3Pqz0c63lcR06ZqmKb1r9k/BSsvkWqbvL+o3LJ+Al0k6v3Ss= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=amazon.com; spf=pass smtp.mailfrom=amazon.co.uk; dkim=pass (1024-bit key) header.d=amazon.com header.i=@amazon.com header.b=TXAZf1dn; arc=none smtp.client-ip=52.119.213.156 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=amazon.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=amazon.co.uk Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=amazon.com header.i=@amazon.com header.b="TXAZf1dn" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.com; i=@amazon.com; q=dns/txt; s=amazon201209; t=1741879399; x=1773415399; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=+fLBMqQ5/8jupgYIbkgkmnTkr87uIxyMhJ72+6lrbYY=; b=TXAZf1dn3YEyx8hGI/PzhZVhocOE2LbZDX4KsLGbt9Vu93UtF0s6JovY 5Hr0acpsiRLVXKT0uK6icHTylPyn5DWXMVLsWJmAh6JaPZ52ye72iNzsI rumMHJ4aRFHsuvzMFV3sLz68nY8SM1QBoIgeSoYoHc7qatQUuDGzQ/2xY M=; X-IronPort-AV: E=Sophos;i="6.14,245,1736812800"; d="scan'208";a="726539233" Received: from iad12-co-svc-p1-lb1-vlan3.amazon.com (HELO smtpout.prod.us-west-2.prod.farcaster.email.amazon.dev) ([10.43.8.6]) by smtp-border-fw-52005.iad7.amazon.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Mar 2025 15:23:13 +0000 Received: from EX19MTAEUB002.ant.amazon.com [10.0.43.254:12275] by smtpin.naws.eu-west-1.prod.farcaster.email.amazon.dev [10.0.37.123:2525] with esmtp (Farcaster) id 2744bddb-b207-422c-ad6c-bfebac843e1d; Thu, 13 Mar 2025 15:23:12 +0000 (UTC) X-Farcaster-Flow-ID: 2744bddb-b207-422c-ad6c-bfebac843e1d Received: from EX19D016EUA001.ant.amazon.com (10.252.50.245) by EX19MTAEUB002.ant.amazon.com (10.252.51.59) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA) id 15.2.1544.14; Thu, 13 Mar 2025 15:23:12 +0000 Received: from EX19MTAUWA001.ant.amazon.com (10.250.64.204) by EX19D016EUA001.ant.amazon.com (10.252.50.245) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA) id 15.2.1544.14; Thu, 13 Mar 2025 15:23:11 +0000 Received: from email-imr-corp-prod-iad-1box-1a-9bbde7a3.us-east-1.amazon.com (10.25.36.214) by mail-relay.amazon.com (10.250.64.204) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA) id 15.2.1544.14 via Frontend Transport; Thu, 13 Mar 2025 15:23:11 +0000 Received: from dev-dsk-kareemem-1c-885b5fe7.eu-west-1.amazon.com (dev-dsk-kareemem-1c-885b5fe7.eu-west-1.amazon.com [10.13.243.223]) by email-imr-corp-prod-iad-1box-1a-9bbde7a3.us-east-1.amazon.com (Postfix) with ESMTPS id 540BE4061C; Thu, 13 Mar 2025 15:23:10 +0000 (UTC) From: Abdelkareem Abdelsaamad To: CC: Kuan-Wei Chiu , Petr Mladek , Sasha Levin , Abdelkareem Abdelsaamad Subject: [PATCH 5.10.y 5.15.y] printk: Fix signed integer overflow when defining LOG_BUF_LEN_MAX Date: Thu, 13 Mar 2025 15:23:07 +0000 Message-ID: <20250313152307.14830-1-kareemem@amazon.com> X-Mailer: git-send-email 2.47.1 Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain From: Kuan-Wei Chiu [ Upstream commit 3d6f83df8ff2d5de84b50377e4f0d45e25311c7a ] Shifting 1 << 31 on a 32-bit int causes signed integer overflow, which leads to undefined behavior. To prevent this, cast 1 to u32 before performing the shift, ensuring well-defined behavior. This change explicitly avoids any potential overflow by ensuring that the shift occurs on an unsigned 32-bit integer. Signed-off-by: Kuan-Wei Chiu Acked-by: Petr Mladek Link: https://lore.kernel.org/r/20240928113608.1438087-1-visitorckw@gmail.com Signed-off-by: Petr Mladek Signed-off-by: Sasha Levin (cherry picked from commit 9a6d43844de2479a3ff8d674c3e2a16172e01598) Signed-off-by: Abdelkareem Abdelsaamad --- kernel/printk/printk.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index a8af93cbc293..3a7fd61c0e7b 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -420,7 +420,7 @@ static u64 clear_seq; /* record buffer */ #define LOG_ALIGN __alignof__(unsigned long) #define __LOG_BUF_LEN (1 << CONFIG_LOG_BUF_SHIFT) -#define LOG_BUF_LEN_MAX (u32)(1 << 31) +#define LOG_BUF_LEN_MAX ((u32)1 << 31) static char __log_buf[__LOG_BUF_LEN] __aligned(LOG_ALIGN); static char *log_buf = __log_buf; static u32 log_buf_len = __LOG_BUF_LEN; -- 2.47.1