From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wr1-f53.google.com (mail-wr1-f53.google.com [209.85.221.53]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 044B730C637 for ; Fri, 26 Jun 2026 08:38:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.221.53 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782463120; cv=none; b=XWZqi8kWa2vfM7BX5pIgi8ghGDHfb8AgSdcDrph/odGvgW2mD7GiZEgdW83Dvs3KILWQEfV1r7Ba4sG2cIHiS0iqkcgiVEiquujyuZyIO+0WuPBAuIkEtiHmE5pN8emi0+Z4U4JoMbTcEP3MNUCT8a5RXa0pv37YCOxiU1mY4fI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782463120; c=relaxed/simple; bh=vnFHcqH8IDVtsBE+Gqq+qvfqnPUS/7yK6vgR180USfY=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=M81KiNx7+4A6pDRbS8kc+XVVHqF3HesTJwRbq3QWpXCFinxK8jUyevtzew7opc0rQLCXdvB1yues84KpqlBhx7x/zDyTGPHFfZOCP/P/JWmG6eiwd6YQHkjXTke3V7MS42L4D2zIIVQQEM/EgLuiosCi+ZXg8lgTu0IZpCSg5sg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=Yv8pfmxn; arc=none smtp.client-ip=209.85.221.53 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Yv8pfmxn" Received: by mail-wr1-f53.google.com with SMTP id ffacd0b85a97d-46ed4f66256so507317f8f.3 for ; Fri, 26 Jun 2026 01:38:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1782463117; x=1783067917; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=knUtWGfRpywQ0S6NVky1uviDI0wg0VlA10MLXXuY7Ac=; b=Yv8pfmxnOY82baWnmeWS6qk9u7Bc59QeoqgKLWM460/vMtGLvZk3hstUE0d+GFQo7E 7lMzzyDgw1q5CulfiUFNHnP47hO/xaRPklKqEPBO5Xv4qpdAPRJ4Vw5UeylvtJ0cIYQw AnU8ZivcdAE+0r6JV8yrZcRxgKW2z2DE5NKmCEfkouD4Ed8SmpRV/aN0Xl8aFCzFjRC+ ocxL58YmCXh+GG+ungw38kmNO+flHsP1KwL++ViDPP5pGr6iwYB8YWqCFxHQ+0NXk8nd D/GYt6wyu6/KibDDVB83auJmfPUuA16uE0QEwcMp9dec78akxuAVK++RlfhKDhJYnOl0 4Wmg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1782463117; x=1783067917; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-gg:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=knUtWGfRpywQ0S6NVky1uviDI0wg0VlA10MLXXuY7Ac=; b=hreUesjpYdtwZF7r5BplkQFShqDy5P5oY2aoQVuZBaepU9sBLwgGfJgUEqzx88qbGX r73vAY8Z5Hee+UNuXyY68J5WIAkf+FDbFRHk+X9G/7bmCAm1wcC1TV+n3wOPmjOyMh/W B1zwItz0UDMh/dM2dr2yCO28krUauRi3qt+FBh95QmT6o38T1MNiVGfqY5UvU3+hSpaW jqVR7efS/sRcC64VSoWUo7//wg8/v0sUBcTNRlzufPtEsKNcBCEESNSDjpIG/mvKLCcw y+VoMf08Jtmyxoe/jVBsywH9erY8+ZlY4NyzId4rs412FCFpn7CqkJFP4WhI2vZQZGv4 rNyQ== X-Forwarded-Encrypted: i=1; AHgh+Rq71TasHoWbVbIm0U3IRlxoXDQWGR+e6j5FMT1aYdxcSgMRDDdFjRryXKf8h6ojeo4r1Ooz/G0xu7gPEhQ=@vger.kernel.org X-Gm-Message-State: AOJu0Yx/GqS8iyI6M76YQSgPJc/UAc+HK/j3IjINNOQsk4fjq3TvIA7v hzteYuY6KC/GVt8P4vTUeaK9UMsocDiKWTd7nNxAOAhnKV2ULuJ1FAyX X-Gm-Gg: AfdE7ckSfBtfFeuRsUfq71R3l6K8vleUdfMUkxS6rUT/E49TExjvatjqxsdPpyi9zV6 s47WE5mZY4L7E47EYh7ZtvqAOQ3bnQJNQNTVFSCrU/cc9ddOfRw3KiVJ9tARLPbUPzJnhS9sFb2 o0wp+OD53NqENmLSTRTDYIShfae/B6Yw0hAJuEACuVfMMfRvB2qHo/vVRDhpcNKNU3hVEwPSl3D BH223/aRmg2VmL4vYHb0qFqHhejh8R2OUtnolM7fOcTohTjyMuaYkcCgCcmr3qyjkSZS9cEgLwk WF3TL2oOen04d8ikx0CkzMKRxFx2WYpS05NwnivKK9Pby+s5NUNwtF9DZJfulfNprbvqfr2Ui2F vNrhEbPieLKkfR3CkIbhaSB5YJbUGeEn0KxzZl450WhV2tTR7GctQRs85qa1mgGrPx5BnjnPy0k sZyHYP+aBLZWGdTwQ7tTwnCLjuCHYxkH3ED5A9GCTs61kA6mlrKptKXPMI/kE3+kZxI5jepw== X-Received: by 2002:a05:6000:24c2:b0:46d:654:d1f1 with SMTP id ffacd0b85a97d-46dc1a91830mr10182515f8f.21.1782463117309; Fri, 26 Jun 2026 01:38:37 -0700 (PDT) Received: from snowdrop.snailnet.com (82-69-66-36.dsl.in-addr.zen.co.uk. [82.69.66.36]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-46c1ee0189esm23876057f8f.9.2026.06.26.01.38.36 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 26 Jun 2026 01:38:36 -0700 (PDT) From: David Laight To: Kees Cook , linux-hardening@vger.kernel.org, kgdb-bugreport@lists.sourceforge.net, linux-kernel@vger.kernel.org Cc: Arnd Bergmann , Arnd Bergmann , Daniel Thompson , Greg Kroah-Hartman , Jason Wessel , David Laight Subject: [PATCH v2 next] drivers/misc/kgdbts: Replace strlen() strcpy() pair with strscpy() Date: Fri, 26 Jun 2026 09:38:21 +0100 Message-Id: <20260626083821.2981-1-david.laight.linux@gmail.com> X-Mailer: git-send-email 2.39.5 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Use the result of strscpy() for the options overflow check, if too long delete the config string. Use two argument strscpy(config, kmessage) to ensure no overflow. Signed-off-by: David Laight --- v2: Note that an overlong config string gets deleted. This is one of a group of patches that remove potentially unbounded strcpy() calls. They are mostly replaced by strscpy() or, when strlen() has just been called, with memcpy() (usually including the '\0'). Calls with copy string literals into arrays are left unchanged. They are safe and easily detected as such. The changes were made by getting the compiler to detect the calls and then fixing the code by hand. Note that all the changes are only compile tested. Some Makefiles were changed to allow files to contain strcpy(). As well as 'difficult to fix' files, this included 'show' functions as they really need to use sysfs_emit() or seq_printf(). All the patches are being sent individually to avoid very long cc lists. Apologies for the terse commit messages and likely unexpected tags. (There are about 100 patches in total.) drivers/misc/kgdbts.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/drivers/misc/kgdbts.c b/drivers/misc/kgdbts.c index 9d3218330f0a..2c8f10b8ac74 100644 --- a/drivers/misc/kgdbts.c +++ b/drivers/misc/kgdbts.c @@ -1069,11 +1069,10 @@ static void kgdbts_run_tests(void) static int __init kgdbts_option_setup(char *opt) { - if (strlen(opt) >= MAX_CONFIG_LEN) { + if (strscpy(config, opt) < 0) { + config[0] = 0; printk(KERN_ERR "kgdbts: config string too long\n"); - return 1; } - strcpy(config, opt); return 1; } @@ -1144,7 +1143,7 @@ static int param_set_kgdbts_var(const char *kmessage, /* Only copy in the string if the init function has not run yet */ if (configured < 0) { - strcpy(config, kmessage); + strscpy(config, kmessage); return 0; } @@ -1153,7 +1152,7 @@ static int param_set_kgdbts_var(const char *kmessage, return -EBUSY; } - strcpy(config, kmessage); + strscpy(config, kmessage); /* Chop out \n char as a result of echo */ if (len && config[len - 1] == '\n') config[len - 1] = '\0'; -- 2.39.5