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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BFCE8C001DB for ; Sun, 13 Aug 2023 15:59:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230110AbjHMP7o (ORCPT ); Sun, 13 Aug 2023 11:59:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56210 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229882AbjHMP7n (ORCPT ); Sun, 13 Aug 2023 11:59:43 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 11B4E19B1; Sun, 13 Aug 2023 08:59:28 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id DCF816337E; Sun, 13 Aug 2023 15:53:23 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id EE6D3C433C8; Sun, 13 Aug 2023 15:53:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1691942003; bh=QhCmGArcIGAUg7xrNAxrgEsBDLrQ7HzLiIbb2cDk0EE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=GV4nCmkyaNbAEyZ+NMIJkMYHWyaqGBsKbkxbgoFo7qEXwGdE8Yefmc/wDXXPrpqOe WM1RRo38/kk2Hv4kn/iy2/ndrLu5JoEFOEHJtI8fx4XYOeEEJIo7pz3jwpbIWhIZWR lUZNXJMO251FeXDX7yIARhzYvGkW5PNPtuW/m0BFvM0P4wHM2rsw8VWRr//lWINfd6 CdAMgTzetQRvPUX04w1H27qqfysReNnrlUtPfH1Vs5DQ7PtGuGlUWiJDpvOejky/VX shcPuB4mIAwzOFi76MG7szfRBMPab3rOhPS4VXyA2yN5X7xHpjXrIDbH3EMiSiE7Lf yrCvYkWcR8f2w== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: "Masami Hiramatsu (Google)" , Steven Rostedt , Sasha Levin , naveen.n.rao@linux.ibm.com, anil.s.keshavamurthy@intel.com, davem@davemloft.net, linux-trace-kernel@vger.kernel.org Subject: [PATCH AUTOSEL 6.4 54/54] kprobes: Prohibit probing on CFI preamble symbol Date: Sun, 13 Aug 2023 11:49:33 -0400 Message-Id: <20230813154934.1067569-54-sashal@kernel.org> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230813154934.1067569-1-sashal@kernel.org> References: <20230813154934.1067569-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.4.10 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-trace-kernel@vger.kernel.org From: "Masami Hiramatsu (Google)" [ Upstream commit de02f2ac5d8cfb311f44f2bf144cc20002f1fbbd ] Do not allow to probe on "__cfi_" or "__pfx_" started symbol, because those are used for CFI and not executed. Probing it will break the CFI. Link: https://lore.kernel.org/all/168904024679.116016.18089228029322008512.stgit@devnote2/ Signed-off-by: Masami Hiramatsu (Google) Reviewed-by: Steven Rostedt (Google) Signed-off-by: Sasha Levin --- kernel/kprobes.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff --git a/kernel/kprobes.c b/kernel/kprobes.c index 00e177de91ccd..3da9726232ff9 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -1545,6 +1545,17 @@ static int check_ftrace_location(struct kprobe *p) return 0; } +static bool is_cfi_preamble_symbol(unsigned long addr) +{ + char symbuf[KSYM_NAME_LEN]; + + if (lookup_symbol_name(addr, symbuf)) + return false; + + return str_has_prefix("__cfi_", symbuf) || + str_has_prefix("__pfx_", symbuf); +} + static int check_kprobe_address_safe(struct kprobe *p, struct module **probed_mod) { @@ -1563,7 +1574,8 @@ static int check_kprobe_address_safe(struct kprobe *p, within_kprobe_blacklist((unsigned long) p->addr) || jump_label_text_reserved(p->addr, p->addr) || static_call_text_reserved(p->addr, p->addr) || - find_bug((unsigned long)p->addr)) { + find_bug((unsigned long)p->addr) || + is_cfi_preamble_symbol((unsigned long)p->addr)) { ret = -EINVAL; goto out; } -- 2.40.1