From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5A16718E354; Mon, 28 Oct 2024 06:42:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730097750; cv=none; b=T4SQhZFSC3GU/pEx5WpXLE8lIUXXTt3cf2sh2XzQBbltLBlpEnilV7gdhkFog9+9fJdczSaKrdtZymjypNZnl2NrWP4gtgSprgi6aLzKLsDG1dav4Uo2fXIbRT5d//1iqMLehDa7e+ALoYaxM9nimCQEedrPKkNVBa6u3r1g8XQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730097750; c=relaxed/simple; bh=zjfrbNPbXHm4J2IfEIQvI4N4z/EsefEXsWTtj14SuNw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=gJ7lDiTPbSaV2xh0VKhdHrooGPHpnyZ5GI9uYREuFc2UHCnKY0EGzevR49ATyW9HXjSBc9HgH3E2ww7ktTEDc78CxyxaimPuZeCQGGcB+6VL//OrLFaMgFNLcvxA1nqk1+1JU619xHUXBY22xkxVhtdRCKthU7MZKwIynNgcApE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=Uj8BGm6Q; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="Uj8BGm6Q" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E19D7C4CEC3; Mon, 28 Oct 2024 06:42:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1730097750; bh=zjfrbNPbXHm4J2IfEIQvI4N4z/EsefEXsWTtj14SuNw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Uj8BGm6QxchSiruqOUvBpuKDW5Gmod9dcze8UuWXjfTOtaFUw625Lp62Evrkm9BHo YmhPBsaPYu3xybNCkzdxpgkjIKahtRhPQLVws7FnZEXFi2xCZrSRKsjjQPhOaZjVEb WZ67+reu18f4J/zutRVprEz4GriR0HnaueAIDM3o= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Mikel Rychliski , "Masami Hiramatsu (Google)" , Sasha Levin Subject: [PATCH 6.6 129/208] tracing/probes: Fix MAX_TRACE_ARGS limit handling Date: Mon, 28 Oct 2024 07:25:09 +0100 Message-ID: <20241028062309.817942889@linuxfoundation.org> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20241028062306.649733554@linuxfoundation.org> References: <20241028062306.649733554@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Mikel Rychliski [ Upstream commit 73f35080477e893aa6f4c8d388352b871b288fbc ] When creating a trace_probe we would set nr_args prior to truncating the arguments to MAX_TRACE_ARGS. However, we would only initialize arguments up to the limit. This caused invalid memory access when attempting to set up probes with more than 128 fetchargs. BUG: kernel NULL pointer dereference, address: 0000000000000020 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: Oops: 0000 [#1] PREEMPT SMP PTI CPU: 0 UID: 0 PID: 1769 Comm: cat Not tainted 6.11.0-rc7+ #8 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-1.fc39 04/01/2014 RIP: 0010:__set_print_fmt+0x134/0x330 Resolve the issue by applying the MAX_TRACE_ARGS limit earlier. Return an error when there are too many arguments instead of silently truncating. Link: https://lore.kernel.org/all/20240930202656.292869-1-mikel@mikelr.com/ Fixes: 035ba76014c0 ("tracing/probes: cleanup: Set trace_probe::nr_args at trace_probe_init") Signed-off-by: Mikel Rychliski Signed-off-by: Masami Hiramatsu (Google) Signed-off-by: Sasha Levin --- kernel/trace/trace_eprobe.c | 7 ++++++- kernel/trace/trace_fprobe.c | 6 +++++- kernel/trace/trace_kprobe.c | 6 +++++- kernel/trace/trace_uprobe.c | 4 +++- 4 files changed, 19 insertions(+), 4 deletions(-) diff --git a/kernel/trace/trace_eprobe.c b/kernel/trace/trace_eprobe.c index b03bc30f85ee3..31bb977670bdf 100644 --- a/kernel/trace/trace_eprobe.c +++ b/kernel/trace/trace_eprobe.c @@ -915,6 +915,11 @@ static int __trace_eprobe_create(int argc, const char *argv[]) } } + if (argc - 2 > MAX_TRACE_ARGS) { + ret = -E2BIG; + goto error; + } + mutex_lock(&event_mutex); event_call = find_and_get_event(sys_name, sys_event); ep = alloc_event_probe(group, event, event_call, argc - 2); @@ -940,7 +945,7 @@ static int __trace_eprobe_create(int argc, const char *argv[]) argc -= 2; argv += 2; /* parse arguments */ - for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) { + for (i = 0; i < argc; i++) { trace_probe_log_set_index(i + 2); ret = trace_eprobe_tp_update_arg(ep, argv, i); if (ret) diff --git a/kernel/trace/trace_fprobe.c b/kernel/trace/trace_fprobe.c index 4f42808155225..f26bb8a90cb54 100644 --- a/kernel/trace/trace_fprobe.c +++ b/kernel/trace/trace_fprobe.c @@ -1103,6 +1103,10 @@ static int __trace_fprobe_create(int argc, const char *argv[]) argc = new_argc; argv = new_argv; } + if (argc > MAX_TRACE_ARGS) { + ret = -E2BIG; + goto out; + } /* setup a probe */ tf = alloc_trace_fprobe(group, event, symbol, tpoint, maxactive, @@ -1119,7 +1123,7 @@ static int __trace_fprobe_create(int argc, const char *argv[]) (unsigned long)tf->tpoint->probestub); /* parse arguments */ - for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) { + for (i = 0; i < argc; i++) { trace_probe_log_set_index(i + 2); ctx.offset = 0; ret = traceprobe_parse_probe_arg(&tf->tp, i, argv[i], &ctx); diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 32c617123f374..12d997bb3e789 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -932,6 +932,10 @@ static int __trace_kprobe_create(int argc, const char *argv[]) argc = new_argc; argv = new_argv; } + if (argc > MAX_TRACE_ARGS) { + ret = -E2BIG; + goto out; + } /* setup a probe */ tk = alloc_trace_kprobe(group, event, addr, symbol, offset, maxactive, @@ -944,7 +948,7 @@ static int __trace_kprobe_create(int argc, const char *argv[]) } /* parse arguments */ - for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) { + for (i = 0; i < argc; i++) { trace_probe_log_set_index(i + 2); ctx.offset = 0; ret = traceprobe_parse_probe_arg(&tk->tp, i, argv[i], &ctx); diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c index d72ac9dde5321..3e7d92d2650bc 100644 --- a/kernel/trace/trace_uprobe.c +++ b/kernel/trace/trace_uprobe.c @@ -556,6 +556,8 @@ static int __trace_uprobe_create(int argc, const char **argv) if (argc < 2) return -ECANCELED; + if (argc - 2 > MAX_TRACE_ARGS) + return -E2BIG; if (argv[0][1] == ':') event = &argv[0][2]; @@ -681,7 +683,7 @@ static int __trace_uprobe_create(int argc, const char **argv) tu->filename = filename; /* parse arguments */ - for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) { + for (i = 0; i < argc; i++) { struct traceprobe_parse_context ctx = { .flags = (is_return ? TPARG_FL_RETURN : 0) | TPARG_FL_USER, }; -- 2.43.0