From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wm1-f47.google.com (mail-wm1-f47.google.com [209.85.128.47]) (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 6434F37B3EB for ; Fri, 27 Feb 2026 18:43:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.47 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772217797; cv=none; b=hcVOIylPOu9hz1M+majW/m9da5iR5dw0QNKG008djp3ZFgW337E2YpqTAWhuQJH9VHwVHasjgOpJCPKO6B+481EU1N27SfJTlm5E2XGRpLBWT7zOcpTuU8MJC5pMX1LOrUrKIn3+n11qk7TTz/DDjpqU56XnGAt+hHWJKqTXIac= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772217797; c=relaxed/simple; bh=Xg9SkSYuyIP7K2AwvcRP9+RTQbFoRux2qRCLJkKXhwU=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=pVDCYvgUA95GOMighPEkZWs/VG0kSE0QpniSnNiKxb81TGhXT5UvtriZr4Kn/ujlM7zWMkApwi0VOBM/Up6u6stVrwQdBPbMEArsuTkzy1ZYeMs1R68+iGjVxECnJ1nL4+2n/FKlHA1ypjtrr2pGJpnBB1lCE8wzzHTJyQU0ZlI= 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=WqUQNX2G; arc=none smtp.client-ip=209.85.128.47 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="WqUQNX2G" Received: by mail-wm1-f47.google.com with SMTP id 5b1f17b1804b1-4833115090dso23816095e9.3 for ; Fri, 27 Feb 2026 10:43:16 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1772217795; x=1772822595; 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=u1t26u1cjkcfN9Mbxl35GlBg7KXEUFupFnY7P32WIcQ=; b=WqUQNX2G5D+lYekVLbW3bH/yIJt8vTdj+qNHEHLYNPAgqmMtQn0mn/SSt1C3934Pai KzKTbJUPupxu5ANOFX7fbMEN4OLhkehFdd6OO/JY4WLhP/6E98LfC9oanSeGXJLAYogq ezQsAjVYIbrh7YFtnzr0fYAnkFlbOqjMvnpyMfJEJayqZVj/DIKRlXi36LdBo78poxWv HaBshglK0dUkQRW065FuC8sYDZNij+ymB2/LLHzR2IZqpaJwnUQz43ZKaduSkvgE/r28 mbGcFuQSIVlwqeTF9Nb7EBlS345JgKAdVzCHBnVGaCvyKQDcwMY3dP8vlA44cQ1yIRum aVOw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1772217795; x=1772822595; 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=u1t26u1cjkcfN9Mbxl35GlBg7KXEUFupFnY7P32WIcQ=; b=BJ9l/eE6AVeqdSuyKTK9/n3Kg/UxGa1O1nsTdClXP7bapksv6ZP4BJuXFm4nTbeLfU 5Q2ouXnAZhwlXCXCP7qzSsS+pikuQh3lOihbz7Qi+l5Lj9cfgG6HDiB8oODkoJOJysqP 14/laXmW/6QvfQZaGygpWw5pNMlTcsGDZfS/2kFnk/nqWgNfYtomVPALGolz8PhUW7ux h9ABZpypmyJUBYMO1PkscwAh9SxQ7SjL9Alt9u2gmhjcqi+jTcAX/xJHUM69QAG/bgEA qbBt2fWst2SoZpeMIAYAkWPnvle6pV/QoJ+sP7eMYQRW+vEaHZKZ1BMx8+iWxZZIbuTQ yGUg== X-Gm-Message-State: AOJu0Yw0VR75CqBQTNo6deZf6wJK7fByz8xC50Ksm0g5u7cpNXAVOE0P 3iHVmkRTqcv8xEupcWvrn2jsa7jbTLiFYi+cMiwUbnFkols2WmVrSegi X-Gm-Gg: ATEYQzwUfPEVTsifkY0XEImWufzzs/3wXS/oHt0ViF2MFW9rWVnDtuZonDb2f6TcdT6 a4f0Cvnkds2ww0IKux+gLeFHH9fUyi9hK0yc5AoXNvbagvh9V3a92wm11gRUAX5MbI1/gP8JfbX 1lEKjpvGUGpxBfoFC76pjvXKFHBCBL8O+3ROVPdUVuDzapMYq0bLOcAeSMS+cwijDlHXdS/CxxT YWBUJCh8a/fUE4FSLQob0G/3Y/L7C7YtaAwzss4g/hLpSb71FX4Jx+L+rZtD5h6bXPAPqYN64vC Odak5OUcqool7kAhILGcMKm7d6zTiCHdkpvVl84G+T+fq+E8qyappNuzGOjN3ws6HjVjj5okKDQ gKH67uTZhC6LOWBrwy5TEgLb5XSkrr7F/t1jANF9hTMGPNun6VNPfzinl7XNyRWwO6jgh4EpzHb wXB+kLVFYZTjUiwyiaWn6D7/Tq/fqulStaQHmPAuJDI+bgbA9gkNzl0xeE3Nhh9wT+73+Wm4Q98 +aXkQunPlrv7YlE2uW2BcfTyB+ApNk= X-Received: by 2002:a05:600c:4591:b0:482:eec4:74c with SMTP id 5b1f17b1804b1-483c9bf0b3cmr59724685e9.22.1772217794576; Fri, 27 Feb 2026 10:43:14 -0800 (PST) Received: from rozandragon.chello.ie (188-141-5-72.dynamic.upc.ie. [188.141.5.72]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-483bfb9d9c6sm64569545e9.14.2026.02.27.10.43.13 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 27 Feb 2026 10:43:14 -0800 (PST) From: David Carlier To: Tejun Heo , David Vernet Cc: linux-kernel@vger.kernel.org, David Carlier Subject: [PATCH] tools/sched_ext: fix strtoul() misuse in scx_hotplug_seq() Date: Fri, 27 Feb 2026 18:43:09 +0000 Message-ID: <20260227184309.13183-1-devnexen@gmail.com> X-Mailer: git-send-email 2.51.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit scx_hotplug_seq() uses strtoul() but validates the result with a negative check (val < 0), which can never be true for an unsigned return value. Use the endptr mechanism to verify the entire string was consumed, and check errno == ERANGE for overflow detection. Signed-off-by: David Carlier --- tools/sched_ext/include/scx/compat.h | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/tools/sched_ext/include/scx/compat.h b/tools/sched_ext/include/scx/compat.h index 8b4897fc8b99..edccc99c7294 100644 --- a/tools/sched_ext/include/scx/compat.h +++ b/tools/sched_ext/include/scx/compat.h @@ -125,6 +125,7 @@ static inline long scx_hotplug_seq(void) { int fd; char buf[32]; + char *endptr; ssize_t len; long val; @@ -137,8 +138,10 @@ static inline long scx_hotplug_seq(void) buf[len] = 0; close(fd); - val = strtoul(buf, NULL, 10); - SCX_BUG_ON(val < 0, "invalid num hotplug events: %lu", val); + errno = 0; + val = strtoul(buf, &endptr, 10); + SCX_BUG_ON(errno == ERANGE || endptr == buf || + (*endptr != '\n' && *endptr != '\0'), "invalid num hotplug events: %ld", val); return val; } -- 2.51.0