| Message ID | cover.1684120990.git.zegao@tencent.com (mailing list archive) |
|---|---|
| Headers | show
Return-Path: <linux-trace-kernel-owner@vger.kernel.org>
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 56138C77B7D
for <linux-trace-kernel@archiver.kernel.org>;
Mon, 15 May 2023 03:54:10 +0000 (UTC)
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
id S238489AbjEODyJ (ORCPT
<rfc822;linux-trace-kernel@archiver.kernel.org>);
Sun, 14 May 2023 23:54:09 -0400
Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52910 "EHLO
lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
with ESMTP id S235181AbjEODyI (ORCPT
<rfc822;linux-trace-kernel@vger.kernel.org>);
Sun, 14 May 2023 23:54:08 -0400
Received: from mail-pf1-x433.google.com (mail-pf1-x433.google.com
[IPv6:2607:f8b0:4864:20::433])
by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 63B4E11B;
Sun, 14 May 2023 20:54:06 -0700 (PDT)
Received: by mail-pf1-x433.google.com with SMTP id
d2e1a72fcca58-64a9335a8e7so17555271b3a.0;
Sun, 14 May 2023 20:54:06 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
d=gmail.com; s=20221208; t=1684122846; x=1686714846;
h=content-transfer-encoding:mime-version:message-id:date:subject:cc
:to:from:from:to:cc:subject:date:message-id:reply-to;
bh=lxpFGoxleToaQwkHibZ+pniT5a0w07wmiTEGO0b16Vo=;
b=JEJP8JtxrzOYfYh3wxVkWNM94qY7zq+DFb35tzFWu7j5IhB7XTbREo9kli6pifyp9V
IoYK1Ya7DP4J32r5YEKtlGuD3MWH0KrpjJdUl+VoWMv5Agj6oouAx8jZaquzF+Ly6ZUA
1O+wdperJ3hT+pgWQ35tWN5TlbeAi6VMqQ8fvZ8W9gdfO6Yxeudo7pDOBbDusD9xMPc5
6RrnLOh1IjAQfgcB0wH8TQOONTgnvCDSOb8Uz3SeSHT73NL71/3On+FrTZ9IEjk2GZU/
NN1hQ7dYRfohetAdsZ8z7+4fE9shjtTVfJ6Ue1Wf2bqPCphzcNlK+gp7GqbkU0xpChjN
C89Q==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
d=1e100.net; s=20221208; t=1684122846; x=1686714846;
h=content-transfer-encoding:mime-version:message-id:date:subject:cc
:to:from:x-gm-message-state:from:to:cc:subject:date:message-id
:reply-to;
bh=lxpFGoxleToaQwkHibZ+pniT5a0w07wmiTEGO0b16Vo=;
b=XwwflQesWe1Vha+7lVHxlYpkPun0sX4ayYgemWCjlFkXi+GZocNqqmIWApfNMFmQTN
Z2mQnDST4KZfwt1mlZzE6kscJQdS/AR1LX4CSgutk/IvCe3wUbvZQzAcXpUTTsAfnigE
MrO+6+7kupndsb/psmtLJQ1shQqpJkiAIY4iMXoPwZKOC/FuGEf9kBE9hTVN6cdbfqCN
h9368teb7eB7evglLuzrobx0nGu4/7y7ktFkbcRZgsEj3cx4aVydCd9s9NVxjxc+PiIA
uGYLJ+z3xJYaSswAbDYFIaoYfkh4MJrjRLxjAnocstx8upxjTP9FAfAtcZ+s5rrUs1oJ
WLeg==
X-Gm-Message-State: AC+VfDzIyJSTEOL8+CfpDi1CKIvqq7ZYyAITZTSu7a3hIrkDQfEgyFH2
0+2MGmfpB5ljY5kOKrKkrS4=
X-Google-Smtp-Source:
ACHHUZ7ZfBxQ4wAM3LwICvh9F8OS1vJ6ac+QqRliDCR133i5ogB8OHH2ppv0BdgUn7eHolk68mFyhw==
X-Received: by 2002:a05:6a00:a23:b0:63d:45f3:9fc with SMTP id
p35-20020a056a000a2300b0063d45f309fcmr39837519pfh.5.1684122845628;
Sun, 14 May 2023 20:54:05 -0700 (PDT)
Received: from localhost.localdomain ([43.132.98.42])
by smtp.googlemail.com with ESMTPSA id
e13-20020a62aa0d000000b00625d84a0194sm10793564pff.107.2023.05.14.20.54.03
(version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256);
Sun, 14 May 2023 20:54:05 -0700 (PDT)
From: Ze Gao <zegao2021@gmail.com>
X-Google-Original-From: Ze Gao <zegao@tencent.com>
To: Paul Walmsley <paul.walmsley@sifive.com>,
Palmer Dabbelt <palmer@dabbelt.com>,
Albert Ou <aou@eecs.berkeley.edu>
Cc: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org,
Ze Gao <zegao@tencent.com>, linux-riscv@lists.infradead.org,
bpf@vger.kernel.org
Subject: [PATCH 0/4] Make fpobe + rethook immune to recursion
Date: Mon, 15 May 2023 11:52:15 +0800
Message-Id: <cover.1684120990.git.zegao@tencent.com>
X-Mailer: git-send-email 2.40.1
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk
List-ID: <linux-trace-kernel.vger.kernel.org>
X-Mailing-List: linux-trace-kernel@vger.kernel.org
|
| Series |
Make fpobe + rethook immune to recursion
|
expand
|
Current fprobe and rethook has some pitfalls and may introduce kernel stack recusion, especially in massive tracing scenario. For example, if (DEBUG_PREEMPT | TRACE_PREEMPT_TOGGLE) , preempt_count_{add, sub} can be traced via ftrace, if we happens to use fprobe + rethook based on ftrace to hook on those functions, recursion is introduced in functions like rethook_trampoline_handler and leads to kernel crash because of stack overflow. Snippets of such bug are like this: [ 56.038709] BUG: #DF stack guard page was hit at 000000000b5b7199 (stack is 00000000f4b5a9b2..00000000af4160ce) [ 56.038713] stack guard page: 0000 [#1] PREEMPT SMP NOPTI [ 56.038715] CPU: 5 PID: 1836 Comm: retsnoop Kdump: loaded Not tainted 6.1.18 #2 [ 56.038717] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.1 05/05/2021 [ 56.038717] BUG: #DF stack guard page was hit at 0000000069dc65a2 (stack is 000000006b9345c5..00000000a221349b) [ 56.038718] RIP: 0010:ftrace_ops_test+0x1a/0x70 [ 56.038721] Code: 89 df e8 79 e2 ff ff e9 6e ff ff ff 0f 1f 40 00 48 81 ec b0 00 00 00 49 89 f1 49 89 f8 31 c0 48 89 e6 b9 16 00 00 00 48 89 f7 <f3> 48 ab 48 85 d2 74 35 49 8b 80 d8 00 00 00 48 8b 40 08 48 89 44 [ 56.038722] RSP: 0018:fffffe5a8bba5fa0 EFLAGS: 00010046 [ 56.038724] RAX: 0000000000000000 RBX: fffffe5a8bba6090 RCX: 0000000000000016 [ 56.038725] RDX: fffffe5a8bba6090 RSI: fffffe5a8bba5fa0 RDI: fffffe5a8bba5fa0 [ 56.038726] RBP: ffffffffb7137910 R08: ffff8b967f827c70 R09: ffffffffb7137910 [ 56.038727] R10: 0000000000000000 R11: 0000000000000000 R12: fffffe5a8bba6090 [ 56.038727] R13: ffffffffb729e2bf R14: ffffffffffffffdf R15: ffff8b967f827c70 [ 56.038728] FS: 00007f6592d6ed00(0000) GS:ffff8b977da00000(0000) knlGS:0000000000000000 [ 56.038730] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 56.038730] CR2: fffffe5a8bba5f98 CR3: 000000010ed94002 CR4: 00000000003726e0 [ 56.038733] Call Trace: [ 56.038735] <#DF> [ 56.038740] ? exc_int3+0xa/0xc0 [ 56.038743] arch_ftrace_ops_list_func+0xc2/0x190 [ 56.038745] ? rethook_trampoline_handler+0x5f/0x140 [ 56.038748] ftrace_regs_call+0x5/0x52 [ 56.038751] ? rethook_trampoline_handler+0x5f/0x140 [ 56.038754] ? osnoise_arch_unregister+0x210/0x210 [ 56.038757] ? preempt_count_add+0x5/0xa0 [ 56.038760] preempt_count_add+0x5/0xa0 [ 56.038762] rethook_trampoline_handler+0x5f/0x140 [ 56.038764] ? rethook_trampoline_handler+0x5f/0x140 [ 56.038766] arch_rethook_trampoline_callback+0x3b/0x50 [ 56.038768] arch_rethook_trampoline+0x2c/0x60 [ 56.038770] ? rethook_trampoline_handler+0x5f/0x140 [ 56.038775] ? rethook_trampoline_handler+0x5f/0x140 [ 56.038778] osnoise_arch_unregister+0x210/0x210 [ 56.038780] ? rethook_trampoline_handler+0x5f/0x140 [ 56.038781] arch_rethook_trampoline_callback+0x3b/0x50 [ 56.038783] arch_rethook_trampoline+0x2c/0x60 [ 56.038785] ? rethook_trampoline_handler+0x5f/0x140 [ 56.038790] ? rethook_trampoline_handler+0x5f/0x140 [ 56.038792] osnoise_arch_unregister+0x210/0x210 [ 56.038794] ? rethook_trampoline_handler+0x5f/0x140 [ 56.038795] arch_rethook_trampoline_callback+0x3b/0x50 [ 56.038797] arch_rethook_trampoline+0x2c/0x60 [ 56.038799] ? rethook_trampoline_handler+0x5f/0x140 [ 56.038804] ? rethook_trampoline_handler+0x5f/0x140 [ 56.038806] osnoise_arch_unregister+0x210/0x210 [ 56.038808] ? rethook_trampoline_handler+0x5f/0x140 [ 56.038810] arch_rethook_trampoline_callback+0x3b/0x50 [ 56.038811] arch_rethook_trampoline+0x2c/0x60 ... [ 56.039133] ? rethook_trampoline_handler+0x5f/0x140 [ 56.039137] ? rethook_trampoline_handler+0x5f/0x140 [ 56.039139] osnoise_arch_unregister+0x210/0x210 [ 56.039141] ? rethook_trampoline_handler+0x5f/0x140 [ 56.039143] arch_rethook_trampoline_callback+0x3b/0x50 [ 56.039144] arch_rethook_trampoline+0x2c/0x60 [ 56.039147] ? rethook_trampoline_handler+0x5f/0x140 [ 56.039151] ? rethook_trampoline_handler+0x5f/0x140 [ 56.039156] ? vsnprintf+0x2a3/0x550 [ 56.039161] ? sprintf+0x4e/0x60 [ 56.039163] ? kallsyms_lookup_buildid+0x5f/0x130 [ 56.039167] ? __sprint_symbol.constprop.0+0xec/0x110 [ 56.039171] ? symbol_string+0xc5/0x150 [ 56.039197] ? vsnprintf+0x33a/0x550 [ 56.039201] ? exc_int3+0xa/0xc0 [ 56.039204] ? exc_int3+0xa/0xc0 [ 56.039205] ? ftrace_regs_call+0x5/0x52 [ 56.039208] ? ftrace_regs_call+0x5/0x52 [ 56.039211] ? lock_acquire+0x25d/0x2e0 [ 56.039214] ? lock_release+0x208/0x460 [ 56.039218] ? is_bpf_text_address+0x67/0xf0 [ 56.039220] ? kernel_text_address+0x111/0x120 [ 56.039223] ? __kernel_text_address+0xe/0x40 [ 56.039225] ? show_trace_log_lvl+0x1d7/0x336 [ 56.039227] ? show_trace_log_lvl+0x1d7/0x336 [ 56.039236] ? __die_body.cold+0x1a/0x1f [ 56.039239] ? die+0x2a/0x50 [ 56.039242] ? handle_stack_overflow+0x49/0x60 [ 56.039245] ? exc_double_fault+0x148/0x180 [ 56.039248] ? asm_exc_double_fault+0x1f/0x30 [ 56.039251] ? rethook_trampoline_handler+0x5f/0x140 [ 56.039252] ? cpu_cgroup_css_free+0x30/0x30 [ 56.039254] ? cpu_cgroup_css_free+0x30/0x30 [ 56.039258] ? ftrace_ops_test+0x1a/0x70 [ 56.039260] </#DF> This bug is found via tool retsnoop which internally uses bpf based on fprobe + rethook Discussion of this bug can be found here: Link: https://lore.kernel.org/bpf/20230510122045.2259-1-zegao@tencent.com/ This patch series fix this problem by adding more recursion detection in each possible entry functions, and also mark these specific to fprobe or rethook which are beyond the recusion-free guarded region notrace. Ze Gao (4): rethook: use preempt_{disable, enable}_notrace in rethook_trampoline_handler fprobe: make fprobe_kprobe_handler recursion free fprobe: add recursion detection in fprobe_exit_handler rehook, fprobe: mark rethook related functions notrace arch/riscv/kernel/probes/rethook.c | 4 +- arch/s390/kernel/rethook.c | 6 +-- arch/x86/kernel/rethook.c | 8 ++-- kernel/trace/fprobe.c | 76 +++++++++++++++++++++++------- kernel/trace/rethook.c | 12 ++--- 5 files changed, 75 insertions(+), 31 deletions(-)