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 74C5BC4332F for ; Thu, 22 Dec 2022 04:35:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234956AbiLVEfo (ORCPT ); Wed, 21 Dec 2022 23:35:44 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51674 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234459AbiLVEfm (ORCPT ); Wed, 21 Dec 2022 23:35:42 -0500 Received: from mail-pj1-x102a.google.com (mail-pj1-x102a.google.com [IPv6:2607:f8b0:4864:20::102a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8555FCE5; Wed, 21 Dec 2022 20:35:40 -0800 (PST) Received: by mail-pj1-x102a.google.com with SMTP id p4so721943pjk.2; Wed, 21 Dec 2022 20:35:40 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=eqY8aB/LUfyDhVYKT66+Nu8cgqW1FRD27QDgXDV2/og=; b=WX1AS4fTu8k2ucM0F8HQjqrVnqwQvjUGJs7NuYNkVUbLbYljKNtJ0E5lMn1sF2xaC9 /aRqhwa2w0tUbdZYMzZdE8kyqqLxst5ZFykA2rZFf1OJKMHRl5nGhXv9hfG0btcFRHne oGnMTp5CATjQ48KtWMhJWeI9pQgD+VD/KmehHGpK1NA+AXIH3ZlCFeSIXmf0hOHoR7vI KMshMKyOSjEkCY4Syp9LGTr3jayEhK+vBHtlUItGHw34yvWuBxqRd8EshP0lmgDI70zE neWRHTd2uhuKxClhZ6oEwf3izOYdUg+8lnb6pA0trTJK48jlLAW4JmNMyOJwET8Xcycy NSyA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; 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=eqY8aB/LUfyDhVYKT66+Nu8cgqW1FRD27QDgXDV2/og=; b=7IvrM6Q+IDcQpnGiIKkImtgIgmSc3wsO/G6KUKeE4ThXyogBzbCshXoL1wiYttA20o dqrfRw4q8qsT4Sn/X2Q8Enm6zH/Rryrqss0xVcVAb6GkOrEclxYY6fdege65o0FdOlRA r2PZPIsfgf9SCIGqbOpR+XNsiQCxKhxvwTJhWjq5gjXCqhBKsIC4wzMxbL/xFOJd8x2v 6vnxGx344FKVsYF8Is6BLbhzQbaw4LA2khtd3xbm1yq5Ld8Ru5ZbMzEE6RdO1TBsEzi1 YPjaslTLtrAAVYZFTG1UsGQK0fGevBCmrCIhO4r/JN/n/5vfJ4T4QrMAGb3QvVMU6Ppm wxGA== X-Gm-Message-State: AFqh2kqNQhVYHnxTRa7JbK2ha3bD4DpKrTZDTjow0oFh/mhRilNvbrik fnRI2yK85/w0shFVK/un5w0sKG4MMg== X-Google-Smtp-Source: AMrXdXss7M9uf5pkMQ8aqp9TDlhKYFbx3C5rG31npL32OJsKTPaR8SQRbCClaIR51760pahwS4jAJA== X-Received: by 2002:a17:902:e903:b0:189:6191:a1b4 with SMTP id k3-20020a170902e90300b001896191a1b4mr4594681pld.55.1671683739837; Wed, 21 Dec 2022 20:35:39 -0800 (PST) Received: from localhost.localdomain ([144.214.0.6]) by smtp.gmail.com with ESMTPSA id j5-20020a170903024500b0018971fba556sm12268258plh.139.2022.12.21.20.35.36 (version=TLS1_3 cipher=TLS_CHACHA20_POLY1305_SHA256 bits=256/256); Wed, 21 Dec 2022 20:35:39 -0800 (PST) From: Hao Sun To: bpf@vger.kernel.org Cc: ast@kernel.org, daniel@iogearbox.net, john.fastabend@gmail.com, andrii@kernel.org, martin.lau@linux.dev, song@kernel.org, yhs@fb.com, kpsingh@kernel.org, sdf@google.com, haoluo@google.com, jolsa@kernel.org, davem@davemloft.net, linux-kernel@vger.kernel.org, Hao Sun Subject: kernel panic: Attempted to kill init! Date: Thu, 22 Dec 2022 12:35:07 +0800 Message-Id: <20221222043507.33037-1-sunhao.th@gmail.com> X-Mailer: git-send-email 2.37.1 (Apple Git-137.1) MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org Hi, This crash can be triggered by executing the C reproducer for multiple times, which just keep loading the following prog as raw tracepoint into kmem_cache_free(). The prog send SIGSEGV to current via bpf_send_signal_thread(), after load this, whoever tries to free mem would trigger this, kernel crashed when this happens to init. Seems we should filter init out in bpf_send_signal_common() by is_global_init(current), or maybe we should check this in the verifier? This can be reproduced on: HEAD commit: 59fe41b5255f selftests/bpf: Add verifier test exercising jit PROBE_MEM logic git tree: bpf-next console output: https://pastebin.com/raw/FMgyvEnH kernel config : https://pastebin.com/raw/XeF6jU43 C reproducer : https://pastebin.com/raw/Tag5N893 func#0 @0 0: R1=ctx(off=0,imm=0) R10=fp0 0: (18) r0 = 0x0 ; R0_w=0 2: (18) r6 = 0x0 ; R6_w=0 4: (18) r7 = 0x0 ; R7_w=0 6: (18) r8 = 0x0 ; R8_w=0 8: (18) r9 = 0x0 ; R9_w=0 10: (2d) if r0 > r0 goto pc+2 last_idx 10 first_idx 0 regs=1 stack=0 before 8: (18) r9 = 0x0 regs=1 stack=0 before 6: (18) r8 = 0x0 regs=1 stack=0 before 4: (18) r7 = 0x0 regs=1 stack=0 before 2: (18) r6 = 0x0 regs=1 stack=0 before 0: (18) r0 = 0x0 last_idx 10 first_idx 0 regs=1 stack=0 before 8: (18) r9 = 0x0 regs=1 stack=0 before 6: (18) r8 = 0x0 regs=1 stack=0 before 4: (18) r7 = 0x0 regs=1 stack=0 before 2: (18) r6 = 0x0 regs=1 stack=0 before 0: (18) r0 = 0x0 11: R0_w=0 11: (b7) r1 = 11 ; R1_w=11 12: (85) call bpf_send_signal_thread#117 ; R0=scalar() 13: (95) exit processed 9 insns (limit 1000000) max_states_per_insn 0 total_states 1 peak_states 1 mark_read 1 Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b CPU: 3 PID: 1 Comm: systemd Not tainted 6.1.0-09652-g59fe41b5255f #148 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x100/0x178 lib/dump_stack.c:106 panic+0x2c4/0x60f kernel/panic.c:275 do_exit.cold+0x63/0xe4 kernel/exit.c:789 do_group_exit+0xd4/0x2a0 kernel/exit.c:950 get_signal+0x2460/0x2600 kernel/signal.c:2858 arch_do_signal_or_restart+0x78/0x5d0 arch/x86/kernel/signal.c:306 exit_to_user_mode_loop kernel/entry/common.c:168 [inline] exit_to_user_mode_prepare+0x15f/0x250 kernel/entry/common.c:203 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:296 do_syscall_64+0x44/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x55e738964df0 Code: 00 31 f6 89 ef 4c 8d 05 be 1b 0d 00 48 8d 15 b0 85 0c 00 31 c0 e8 f0 c3 ff ff e9 1c ff ff ff 66 66 2e 0f 1f 84 00 00 00 00 00 <41> 57 41 56 41 55 41 54 41 89 fc 55 53 48 81 ec 48 01 00 00 64 48 RSP: 002b:00007ffeb8e87bb8 EFLAGS: 00000246 ORIG_RAX: 00000000000000f7 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f29dc8a6bc1 RDX: 00007ffeb8e87bc0 RSI: 00007ffeb8e87cf0 RDI: 000000000000000b RBP: 00007ffeb90b73c0 R08: 0000000000000000 R09: 0000000000000002 R10: 0000000000000004 R11: 0000000000000246 R12: 00007f29dc3f76c8 R13: 000000000000294d R14: 0000000000000000 R15: 00007ffeb9686870 Kernel Offset: disabled Rebooting in 86400 seconds..