From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oi1-f208.google.com (mail-oi1-f208.google.com [209.85.167.208]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 06AEF27380A for ; Mon, 4 May 2026 06:39:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.167.208 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777876773; cv=none; b=utFiMKzVQOrWXaDQlXkCUwk+dWCMni4u0reqCaIpDckOCEPCGHJeR41J2U2DYa8QLQicOAuTggbxvhc/hsiUJKwEN3xfkgQG8t4wybfcN/AJ64ftiGeZaD5mBnEWrmyKFc6zrVDhLISxn4HFAEDfvBZ3DouwZqReUYoOnaRotO8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777876773; c=relaxed/simple; bh=1Qs0DDzuGyBjMXbYIUZe00wLbA0MzP8qGoD+rUEysTc=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=NyYjgMLgxHxtRCNmB2dVmsDjy9eLUcjAQ1daEp+OEohoVsYgzVDAs4tmx26PuI98qBGPdnGWsOCn0E9blRBu17lhlAz/I2edX+QnYLA8gjlrBVOpwp//nMqbw2V6zvNsWA+4fgHz/dDie+2dGuu6sqpJgeCn6o+hU1Zlua6iWqY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=209.85.167.208 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-oi1-f208.google.com with SMTP id 5614622812f47-46ff0cb3a36so5225896b6e.2 for ; Sun, 03 May 2026 23:39:31 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1777876771; x=1778481571; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=vUNdkvrNnYEQQkZBw5+AsByBP+nxlstl8VuB452P2JU=; b=oyArVpAjnw88s2Hz3CwNoPo3SDCK2/niAoK+qsXnaz5CxCmT6zTwrgH1acgAqbPA1U GA8EWmxafSaPKPu22y0SFNgSXt60bMRrkWZeJpyv1tvx+cOjqY0PVj4lUFPQzxv7HZlZ igwBG7iUqft/3lpL8Nag5sV9r//mGO5Nh4vbGCPWjGO2JTU1G8Q7VUkjlPxdG/nvuY82 kOMZynIOKRtckyV7+I+sk+JiiTmPBrdkzq//DuUcGEoM+3QBxDsHtBCGMVOdcX1idRqa yEk8W15svMUFi1qanpZu4OZ4hxJ+FsMV4rQULpd/FijGmW41oNsbaH0Dk2YgkaIH3THH twnw== X-Forwarded-Encrypted: i=1; AFNElJ8Dc+cwGyakbtfZQ2QlknJA0vMLXbgS+DBwlNhPROuboTxxYut793ObI6Q4sqreS8NJAx2uU74=@vger.kernel.org X-Gm-Message-State: AOJu0YxLT4HyOHMdt7eDLR2rznylxpnuRZ+CNZgRGzEjtNDFrX73dyw+ e+8zgBDclrvmC7bMCrVycnf1HbM3BF8+uyynoIrfriswt9RQi87ip3l4ZbPSrHhsAH1joyI/gZd FhKpPXTNS2jpGo0CeogxedZnpX36uEKl0ew13OEBa2y6qND7s1W8XpT20UIc= Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6820:61e:b0:67b:baae:3339 with SMTP id 006d021491bc7-69697db76a6mr4298628eaf.45.1777876771001; Sun, 03 May 2026 23:39:31 -0700 (PDT) Date: Sun, 03 May 2026 23:39:30 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <69f83f22.170a0220.13cc2.0004.GAE@google.com> Subject: [syzbot] [net?] general protection fault in rt6_insert_exception From: syzbot To: davem@davemloft.net, dsahern@kernel.org, edumazet@google.com, horms@kernel.org, idosch@nvidia.com, kuba@kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, pabeni@redhat.com, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 66edb901bf87 Merge tag 'v7.1-p3' of git://git.kernel.org/p.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=15b40d06580000 kernel config: https://syzkaller.appspot.com/x/.config?x=d0f0911eedbc130a dashboard link: https://syzkaller.appspot.com/bug?extid=01f005f9c6387ca6f6dd compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44 userspace arch: i386 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-66edb901.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/8741b8f9dedf/vmlinux-66edb901.xz kernel image: https://storage.googleapis.com/syzbot-assets/675ec9fff2a9/bzImage-66edb901.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+01f005f9c6387ca6f6dd@syzkaller.appspotmail.com kvm_intel: set kvm_intel.dump_invalid_vmcs=1 to dump internal KVM state. Oops: general protection fault, probably for non-canonical address 0xdffffc00000000bc: 0000 [#1] SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x00000000000005e0-0x00000000000005e7] CPU: 0 UID: 0 PID: 7890 Comm: syz.2.502 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 RIP: 0010:fib6_mtu net/ipv6/route.c:1648 [inline] RIP: 0010:rt6_insert_exception+0x9eb/0x10a0 net/ipv6/route.c:1753 Code: 3b 14 cf f7 45 85 f6 0f 85 1d 02 00 00 e8 7d 19 cf f7 48 8d bb e0 05 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 89 RSP: 0000:ffffc9000610f120 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffc9000c001000 RDX: 00000000000000bc RSI: ffffffff8a38bc83 RDI: 00000000000005e0 RBP: ffff888052f06000 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffff888042d16c00 R13: ffff888042d16cc8 R14: 0000000000000001 R15: 0000000000000500 FS: 0000000000000000(0000) GS:ffff88809717d000(0063) knlGS:00000000f540db40 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 00000000f73c6d50 CR3: 000000006eff0000 CR4: 0000000000352ef0 Call Trace: __ip6_rt_update_pmtu+0x555/0xd60 net/ipv6/route.c:2982 ip6_update_pmtu+0x34f/0x3b0 net/ipv6/route.c:3014 icmpv6_err+0x2a2/0x3f0 net/ipv6/icmp.c:82 icmpv6_notify+0x35e/0x820 net/ipv6/icmp.c:1087 icmpv6_rcv+0x10bf/0x1ae0 net/ipv6/icmp.c:1228 ip6_protocol_deliver_rcu+0xf97/0x1500 net/ipv6/ip6_input.c:478 ip6_input_finish+0x1e4/0x4a0 net/ipv6/ip6_input.c:529 NF_HOOK include/linux/netfilter.h:318 [inline] NF_HOOK include/linux/netfilter.h:312 [inline] ip6_input+0x105/0x2f0 net/ipv6/ip6_input.c:540 ip6_mc_input+0x513/0xf50 net/ipv6/ip6_input.c:630 dst_input include/net/dst.h:480 [inline] ip6_rcv_finish net/ipv6/ip6_input.c:119 [inline] NF_HOOK include/linux/netfilter.h:318 [inline] NF_HOOK include/linux/netfilter.h:312 [inline] ipv6_rcv+0x34c/0x3d0 net/ipv6/ip6_input.c:351 __netif_receive_skb_one_core+0x12d/0x1e0 net/core/dev.c:6202 __netif_receive_skb+0x1f/0x120 net/core/dev.c:6315 netif_receive_skb_internal net/core/dev.c:6401 [inline] netif_receive_skb+0x13b/0x7f0 net/core/dev.c:6460 tun_rx_batched.isra.0+0x3f6/0x750 drivers/net/tun.c:1511 tun_get_user+0x1e31/0x3c20 drivers/net/tun.c:1955 tun_chr_write_iter+0xdc/0x200 drivers/net/tun.c:2001 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x6ac/0x1070 fs/read_write.c:688 ksys_write+0x12a/0x250 fs/read_write.c:740 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] do_int80_emulation+0x141/0x700 arch/x86/entry/syscall_32.c:172 asm_int80_emulation+0x1a/0x20 arch/x86/include/asm/idtentry.h:621 RIP: 0023:0xf715616b Code: 57 56 53 8b 44 24 14 f6 00 08 75 23 8b 44 24 18 8b 5c 24 1c 8b 4c 24 20 8b 54 24 24 8b 74 24 28 8b 7c 24 2c 8b 6c 24 30 cd 80 <5b> 5e 5f 5d c3 5b 5e 5f 5d e9 f7 a1 ff ff 66 90 66 90 66 90 90 53 RSP: 002b:00000000f540d44c EFLAGS: 00000246 ORIG_RAX: 0000000000000004 RAX: ffffffffffffffda RBX: 00000000000000c8 RCX: 0000000080000640 RDX: 000000000000007a RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:fib6_mtu net/ipv6/route.c:1648 [inline] RIP: 0010:rt6_insert_exception+0x9eb/0x10a0 net/ipv6/route.c:1753 Code: 3b 14 cf f7 45 85 f6 0f 85 1d 02 00 00 e8 7d 19 cf f7 48 8d bb e0 05 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 89 RSP: 0000:ffffc9000610f120 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffc9000c001000 RDX: 00000000000000bc RSI: ffffffff8a38bc83 RDI: 00000000000005e0 RBP: ffff888052f06000 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffff888042d16c00 R13: ffff888042d16cc8 R14: 0000000000000001 R15: 0000000000000500 FS: 0000000000000000(0000) GS:ffff88809717d000(0063) knlGS:00000000f540db40 CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 CR2: 00000000f73c6d50 CR3: 000000006eff0000 CR4: 0000000000352ef0 ---------------- Code disassembly (best guess): 0: 3b 14 cf cmp (%rdi,%rcx,8),%edx 3: f7 45 85 f6 0f 85 1d testl $0x1d850ff6,-0x7b(%rbp) a: 02 00 add (%rax),%al c: 00 e8 add %ch,%al e: 7d 19 jge 0x29 10: cf iret 11: f7 48 8d bb e0 05 00 testl $0x5e0bb,-0x73(%rax) 18: 00 48 b8 add %cl,-0x48(%rax) 1b: 00 00 add %al,(%rax) 1d: 00 00 add %al,(%rax) 1f: 00 fc add %bh,%ah 21: ff lcall (bad) 22: df 48 89 fisttps -0x77(%rax) 25: fa cli 26: 48 c1 ea 03 shr $0x3,%rdx * 2a: 0f b6 14 02 movzbl (%rdx,%rax,1),%edx <-- trapping instruction 2e: 48 89 f8 mov %rdi,%rax 31: 83 e0 07 and $0x7,%eax 34: 83 c0 03 add $0x3,%eax 37: 38 d0 cmp %dl,%al 39: 7c 08 jl 0x43 3b: 84 d2 test %dl,%dl 3d: 0f .byte 0xf 3e: 85 .byte 0x85 3f: 89 .byte 0x89 --- This report is generated by a bot. 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