From: syzbot <syzbot+c1e04a422bbc0f0f2921@syzkaller.appspotmail.com>
To: andrii@kernel.org, ast@kernel.org, bpf@vger.kernel.org,
daniel@iogearbox.net, davem@davemloft.net, eddyz87@gmail.com,
haoluo@google.com, hawk@kernel.org, john.fastabend@gmail.com,
jolsa@kernel.org, kpsingh@kernel.org, kuba@kernel.org,
linux-kernel@vger.kernel.org, martin.lau@linux.dev,
netdev@vger.kernel.org, sdf@fomichev.me, song@kernel.org,
syzkaller-bugs@googlegroups.com, yonghong.song@linux.dev
Subject: Re: [syzbot] [bpf?] [net?] stack segment fault in dev_hash_map_redirect
Date: Fri, 05 Jul 2024 22:08:22 -0700 [thread overview]
Message-ID: <000000000000432cc7061c8d2b68@google.com> (raw)
In-Reply-To: <00000000000079d168061c36ce83@google.com>
syzbot has found a reproducer for the following issue on:
HEAD commit: 0b58e108042b Add linux-next specific files for 20240703
git tree: linux-next
console+strace: https://syzkaller.appspot.com/x/log.txt?x=165ce371980000
kernel config: https://syzkaller.appspot.com/x/.config?x=ed034204f2e40e53
dashboard link: https://syzkaller.appspot.com/bug?extid=c1e04a422bbc0f0f2921
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=14987969980000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=11955485980000
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/1d079762feae/disk-0b58e108.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/e53996c8d8c2/vmlinux-0b58e108.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a0bf21cdd844/bzImage-0b58e108.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c1e04a422bbc0f0f2921@syzkaller.appspotmail.com
Oops: stack segment: 0000 [#1] PREEMPT SMP KASAN PTI
CPU: 0 UID: 0 PID: 5094 Comm: syz-executor316 Not tainted 6.10.0-rc6-next-20240703-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
RIP: 0010:bpf_net_ctx_get_ri include/linux/filter.h:788 [inline]
RIP: 0010:__bpf_xdp_redirect_map include/linux/filter.h:1699 [inline]
RIP: 0010:dev_hash_map_redirect+0x64/0x620 kernel/bpf/devmap.c:1022
Code: 00 48 89 d8 48 c1 e8 03 42 80 3c 38 00 74 08 48 89 df e8 9f 9c 3d 00 48 8b 03 48 89 44 24 08 48 8d 58 38 48 89 dd 48 c1 ed 03 <42> 0f b6 44 3d 00 84 c0 0f 85 f5 03 00 00 44 8b 33 44 89 f6 83 e6
RSP: 0018:ffffc9000356f958 EFLAGS: 00010202
RAX: 0000000000000000 RBX: 0000000000000038 RCX: ffff8880276e9e00
RDX: 0000000000000000 RSI: 000000000356f9b0 RDI: ffff88802f22f000
RBP: 0000000000000007 R08: 0000000000000007 R09: ffffffff81b5ee2f
R10: 0000000000000004 R11: ffff8880276e9e00 R12: 0000000000000008
R13: 000000000356f9b0 R14: 0000000000000000 R15: dffffc0000000000
FS: 000055557ccb9380(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000021d5ab98 CR3: 0000000022250000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
bpf_prog_ec9efaa32d58ce69+0x56/0x5a
__bpf_prog_run include/linux/filter.h:691 [inline]
bpf_prog_run_xdp include/net/xdp.h:514 [inline]
tun_build_skb drivers/net/tun.c:1711 [inline]
tun_get_user+0x3321/0x4560 drivers/net/tun.c:1819
tun_chr_write_iter+0x113/0x1f0 drivers/net/tun.c:2048
new_sync_write fs/read_write.c:497 [inline]
vfs_write+0xa72/0xc90 fs/read_write.c:590
ksys_write+0x1a0/0x2c0 fs/read_write.c:643
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbd788a7f10
Code: 40 00 48 c7 c2 b8 ff ff ff f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 80 3d b1 e1 07 00 00 74 17 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 58 c3 0f 1f 80 00 00 00 00 48 83 ec 28 48 89
RSP: 002b:00007ffde33a9838 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fbd788a7f10
RDX: 000000000000004e RSI: 0000000020000540 RDI: 00000000000000c8
RBP: 0000000000000000 R08: 00007ffde33a9968 R09: 00007ffde33a9968
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:bpf_net_ctx_get_ri include/linux/filter.h:788 [inline]
RIP: 0010:__bpf_xdp_redirect_map include/linux/filter.h:1699 [inline]
RIP: 0010:dev_hash_map_redirect+0x64/0x620 kernel/bpf/devmap.c:1022
Code: 00 48 89 d8 48 c1 e8 03 42 80 3c 38 00 74 08 48 89 df e8 9f 9c 3d 00 48 8b 03 48 89 44 24 08 48 8d 58 38 48 89 dd 48 c1 ed 03 <42> 0f b6 44 3d 00 84 c0 0f 85 f5 03 00 00 44 8b 33 44 89 f6 83 e6
RSP: 0018:ffffc9000356f958 EFLAGS: 00010202
RAX: 0000000000000000 RBX: 0000000000000038 RCX: ffff8880276e9e00
RDX: 0000000000000000 RSI: 000000000356f9b0 RDI: ffff88802f22f000
RBP: 0000000000000007 R08: 0000000000000007 R09: ffffffff81b5ee2f
R10: 0000000000000004 R11: ffff8880276e9e00 R12: 0000000000000008
R13: 000000000356f9b0 R14: 0000000000000000 R15: dffffc0000000000
FS: 000055557ccb9380(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000021d5ab98 CR3: 0000000022250000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
0: 00 48 89 add %cl,-0x77(%rax)
3: d8 48 c1 fmuls -0x3f(%rax)
6: e8 03 42 80 3c call 0x3c80420e
b: 38 00 cmp %al,(%rax)
d: 74 08 je 0x17
f: 48 89 df mov %rbx,%rdi
12: e8 9f 9c 3d 00 call 0x3d9cb6
17: 48 8b 03 mov (%rbx),%rax
1a: 48 89 44 24 08 mov %rax,0x8(%rsp)
1f: 48 8d 58 38 lea 0x38(%rax),%rbx
23: 48 89 dd mov %rbx,%rbp
26: 48 c1 ed 03 shr $0x3,%rbp
* 2a: 42 0f b6 44 3d 00 movzbl 0x0(%rbp,%r15,1),%eax <-- trapping instruction
30: 84 c0 test %al,%al
32: 0f 85 f5 03 00 00 jne 0x42d
38: 44 8b 33 mov (%rbx),%r14d
3b: 44 89 f6 mov %r14d,%esi
3e: 83 .byte 0x83
3f: e6 .byte 0xe6
---
If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.
prev parent reply other threads:[~2024-07-06 5:08 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-07-01 22:06 [syzbot] [bpf?] [net?] stack segment fault in dev_hash_map_redirect syzbot
2024-07-06 5:08 ` syzbot [this message]
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