From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 28B9DC4332F for ; Wed, 1 Dec 2021 12:35:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=wWYmpM4wZLZvad7sXpKopLKg+VDHeng5Z3M0O9jL3Z4=; b=GAzHiYMVosdMTa oW/Xm6QNn5VDDgRa3uWvUfQfghg1Sxa8HKJTZmYGEl2bDaojVd+sMf2vj8FTQBdT0sqyS1KhBXSH3 36vWUt/D6nmL9HCa3RmZLAcSJainNL9MUhCilY3hRsYJ+LZpOv9L1zmIciqNV6Yu0NkC+SUeHtz69 F86WhX4iB9MY+Q6bNOWYbVTkqQsMOD6pK2bdLsWYUq2dePgJ8VB+IV6AaFLZaK5HuSFt2YQTdTl1D HLu9aRQ9mA6s8A1IADy8GYntpEjJcF/fbA/4S3T74IAAIA8SMLdQbMvmt0tJfYmO9Vlv2HywWwMG6 lMHQluEW1nED4hEgu8BQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1msOoV-008TpU-Mi; Wed, 01 Dec 2021 12:34:19 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1msOoL-008TmL-1F; Wed, 01 Dec 2021 12:34:10 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 09BE0147A; Wed, 1 Dec 2021 04:34:08 -0800 (PST) Received: from e127744.cambridge.arm.com (e127744.cambridge.arm.com [10.1.32.151]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 841A53F694; Wed, 1 Dec 2021 04:34:04 -0800 (PST) From: German Gomez To: linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, acme@kernel.org Cc: German Gomez , John Garry , Will Deacon , Mathieu Poirier , Leo Yan , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , linux-arm-kernel@lists.infradead.org, linux-csky@vger.kernel.org, linux-riscv@lists.infradead.org Subject: [PATCH v1 1/4] perf tools: Prevent out-of-bounds access to registers Date: Wed, 1 Dec 2021 12:33:29 +0000 Message-Id: <20211201123334.679131-2-german.gomez@arm.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20211201123334.679131-1-german.gomez@arm.com> References: <20211201123334.679131-1-german.gomez@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20211201_043409_150790_4AA6EBF6 X-CRM114-Status: GOOD ( 13.21 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org The size of the cache of register values is arch-dependant (PERF_REGS_MAX). This has the potential of causing an out-of-bounds access in the function "perf_reg_value" if the local architecture contains less registers than the one the perf.data file was recorded on. Since the maximum number of registers is bound by the bitmask "u64 cache_mask", and the size of the cache when running under x86 systems is 64 already, fix the size to 64 and add a range-check to the function "perf_reg_value" to prevent out-of-bounds access. Signed-off-by: German Gomez --- tools/perf/util/event.h | 5 ++++- tools/perf/util/perf_regs.c | 3 +++ 2 files changed, 7 insertions(+), 1 deletion(-) diff --git a/tools/perf/util/event.h b/tools/perf/util/event.h index 95ffed663..c59331eea 100644 --- a/tools/perf/util/event.h +++ b/tools/perf/util/event.h @@ -44,13 +44,16 @@ struct perf_event_attr; /* perf sample has 16 bits size limit */ #define PERF_SAMPLE_MAX_SIZE (1 << 16) +/* number of register is bound by the number of bits in regs_dump::mask (64) */ +#define PERF_SAMPLE_REGS_CACHE_SIZE (8 * sizeof(u64)) + struct regs_dump { u64 abi; u64 mask; u64 *regs; /* Cached values/mask filled by first register access. */ - u64 cache_regs[PERF_REGS_MAX]; + u64 cache_regs[PERF_SAMPLE_REGS_CACHE_SIZE]; u64 cache_mask; }; diff --git a/tools/perf/util/perf_regs.c b/tools/perf/util/perf_regs.c index 5ee47ae15..06a7461ba 100644 --- a/tools/perf/util/perf_regs.c +++ b/tools/perf/util/perf_regs.c @@ -25,6 +25,9 @@ int perf_reg_value(u64 *valp, struct regs_dump *regs, int id) int i, idx = 0; u64 mask = regs->mask; + if ((u64)id >= PERF_SAMPLE_REGS_CACHE_SIZE) + return -EINVAL; + if (regs->cache_mask & (1ULL << id)) goto out; -- 2.25.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel