From patchwork Tue Jan 23 00:27:47 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kees Cook X-Patchwork-Id: 13526708 Received: from mail-pf1-f173.google.com (mail-pf1-f173.google.com [209.85.210.173]) (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 D7D171615B5 for ; Tue, 23 Jan 2024 00:36:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.173 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1705970183; cv=none; b=IWepVfquKoTeDOtHKY0wQ70H9OblV1EghcK6rDENLlKGJ2k0HkcSgGxjog/oQkxGTl8W+w6STFTX1jGs+XQXkfU8g39AZJ4q28CWzZ7VHadSbOAy5SG25f0m2tcdQAyb3EZS9nZnMVPlcRiQXZUCV2ff3Q4CLCOXXnvGeYlA3xI= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1705970183; c=relaxed/simple; bh=LBqk/a/7XxyM37MkXdksahXfcAh3M0YpOfyluKrlFV0=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=OY2vElNJvRvdnoP9/xIVcEOiOLchkQDqxHKGeGWfWQdxU76j6mL4FE/9ssBO2Ib5KAXiBpJ24KKulqnj1QTem3cncge8tkSjGYYy3WxbiYq6bOtxHZaloSJ9VvOkhZf/1FiZkfo9QDwPwIOyVIANRTPEnehprz7y71sr/sACo18= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=chromium.org; spf=pass smtp.mailfrom=chromium.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b=GCwh5Ys5; arc=none smtp.client-ip=209.85.210.173 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=chromium.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=chromium.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="GCwh5Ys5" Received: by mail-pf1-f173.google.com with SMTP id d2e1a72fcca58-6dbd07916d0so2222442b3a.0 for ; Mon, 22 Jan 2024 16:36:21 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; t=1705970181; x=1706574981; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=XUCj35B+IoUqLMsvIqNWwmNsYz5bFEZJWHH794ML50A=; b=GCwh5Ys5AreNGnJv/o5MlywdeWL+y/chxDSHj197Kcl65QXHWa/QrusK3ZOTD8lhq9 AoucqwVyfC2267GBWyiT9UUNs0e4MK/Fm63YrIjOfzaz6VsyUcf4aCwCac/yAqDb2vyR PEKbRWcUWlhwUm7GcO+gaCdfhkCEWJy62yo5Y= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1705970181; x=1706574981; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=XUCj35B+IoUqLMsvIqNWwmNsYz5bFEZJWHH794ML50A=; b=KDuVG4blEigjCxSBQKDEmJA6AEasMN3FKsf3CZZsl25FDLmtmUUW3PI7mdC9akKT+6 iCHiU6JFLNWSgl9BPFiwSQzEOeErcLKE+MeE9Q8ygseDgqZb0owxus9PfA7PY5Uio4XT CHIQQzuG6bDRV4hjw5la7ZmTkeYVJ3oSrCMzNzxnIba0rkKHP+AZJMc79L3ynl1w//z8 nJfcAfQySYGH1SapLxyor97YvUE3dIN8aRbrvtiQoKBuQrnPRiEkWdxYRN5G+szonBVP CZMjMroPDSTAyQ0JdWmGpsOtX6CTKc0OwwwplZKP2/bPC/NB3zz/jH3aMkorQY8A7Q5v XdHg== X-Gm-Message-State: AOJu0YyJnGUvooLyhDbM7RoeeyfRNbLI+V7mIt5sDm5rEg9MiLZBFpb3 BfdNZcGo2AJapo+whHc5oK/ru2BkrkUKa9/QbxpruHjH8SDgs3/c5QSG+Aidiw== X-Google-Smtp-Source: AGHT+IGHAOZ5RbrxlekwcgptdcBkTzY/+KlPMJsJzP8k7ICUY18jNvt4AfpnzbQWNGfW72d9WEsgGg== X-Received: by 2002:a05:6a20:72a9:b0:19c:4dca:a86 with SMTP id o41-20020a056a2072a900b0019c4dca0a86mr1877300pzk.66.1705970181377; Mon, 22 Jan 2024 16:36:21 -0800 (PST) Received: from www.outflux.net ([198.0.35.241]) by smtp.gmail.com with ESMTPSA id u20-20020aa78494000000b006dab0d09ef0sm10164283pfn.45.2024.01.22.16.36.13 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 22 Jan 2024 16:36:18 -0800 (PST) From: Kees Cook To: linux-hardening@vger.kernel.org Cc: Kees Cook , "James E.J. Bottomley" , "Martin K. Petersen" , linux-scsi@vger.kernel.org, "Gustavo A. R. Silva" , Bill Wendling , Justin Stitt , linux-kernel@vger.kernel.org Subject: [PATCH 72/82] scsi: sd_zbc: Refactor intentional wrap-around test Date: Mon, 22 Jan 2024 16:27:47 -0800 Message-Id: <20240123002814.1396804-72-keescook@chromium.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240122235208.work.748-kees@kernel.org> References: <20240122235208.work.748-kees@kernel.org> Precedence: bulk X-Mailing-List: linux-hardening@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=1962; i=keescook@chromium.org; h=from:subject; bh=LBqk/a/7XxyM37MkXdksahXfcAh3M0YpOfyluKrlFV0=; b=owEBbQKS/ZANAwAKAYly9N/cbcAmAcsmYgBlrwgLEf/Cz5+23/+enVsVIkLx8QMLFJ93FtDfb s/ses2igzyJAjMEAAEKAB0WIQSlw/aPIp3WD3I+bhOJcvTf3G3AJgUCZa8ICwAKCRCJcvTf3G3A JpEDD/9MrWjc6bOmLUNDTK8C65JpgDJf58ljxn97yBwSxMLQcWeG03LZ2GDDyQBTzP63WppqnI7 ikfMG8tyk4rfJg5sDwA2nSAc0ZBsSwVQFMlPTIH7bAaKqsDDw4a8GBqBMXyJIqODCBt4pT4VDsF cYb3ksk+uVx42hbg+85EHCyBBDtW+UgTWsJnEKTG7SYN2rdS8mxVACStdqvaijZrgDeQucGZBV0 5t3y06uoK9tzxx11ps0PiwZD1Eb30y/j1Puzv+wuIik8LpMUijX/QOF4spJeXn9Uf/kTrdiXrtD CAjxej0vsOSSdJgXMK1SdKvSfYjGaYdXkI8LiM/rUs5o0ZUUvZiZu53llRz5BRrqDAIFfUGeJP/ bvu8LIIJHygXBw0InDKzOgSz7a9VcQOlWz7oHfbeZ8NUVwheYgIl+J4lUiBVKR7eXEg2Gi7L24O HyHMkzEePZv03dkGkLTu9NiV9a5Ncv4emMcauHel4wVwzEk/akthm0xu2LcJFkqvkcL/bN1ayT6 yRwPu5VutSooWXVuKdM3Zq9Q/bn2TJJTuZAZo2zaMG6ugxX/03/6zTGuC0Mz5z17SedNM9c/6sv zA29mGYVnEl4G+dotIhrrvQ2UU2LJZEWJCtvONixSMW665U+C3gyac/J1KHzBgFDXuWD98EU+xD AiN7s4tQdaMO3kA== X-Developer-Key: i=keescook@chromium.org; a=openpgp; fpr=A5C3F68F229DD60F723E6E138972F4DFDC6DC026 In an effort to separate intentional arithmetic wrap-around from unexpected wrap-around, we need to refactor places that depend on this kind of math. One of the most common code patterns of this is: VAR + value < VAR Notably, this is considered "undefined behavior" for signed and pointer types, which the kernel works around by using the -fno-strict-overflow option in the build[1] (which used to just be -fwrapv). Regardless, we want to get the kernel source to the position where we can meaningfully instrument arithmetic wrap-around conditions and catch them when they are unexpected, regardless of whether they are signed[2], unsigned[3], or pointer[4] types. Refactor open-coded wrap-around addition test to use add_would_overflow(). This paves the way to enabling the wrap-around sanitizers in the future. Link: https://git.kernel.org/linus/68df3755e383e6fecf2354a67b08f92f18536594 [1] Link: https://github.com/KSPP/linux/issues/26 [2] Link: https://github.com/KSPP/linux/issues/27 [3] Link: https://github.com/KSPP/linux/issues/344 [4] Cc: "James E.J. Bottomley" Cc: "Martin K. Petersen" Cc: linux-scsi@vger.kernel.org Signed-off-by: Kees Cook --- drivers/scsi/sd_zbc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/scsi/sd_zbc.c b/drivers/scsi/sd_zbc.c index 26af5ab7d7c1..2c377e4cdb2b 100644 --- a/drivers/scsi/sd_zbc.c +++ b/drivers/scsi/sd_zbc.c @@ -295,7 +295,7 @@ int sd_zbc_report_zones(struct gendisk *disk, sector_t sector, (lba < start_lba || lba >= start_lba + zone_length)) || (zone_idx > 0 && start_lba != lba) || - start_lba + zone_length < start_lba) { + add_would_overflow(start_lba, zone_length)) { sd_printk(KERN_ERR, sdkp, "Zone %d at LBA %llu is invalid: %llu + %llu\n", zone_idx, lba, start_lba, zone_length);