syzbot


divide error in __tcp_select_window (2)

Status: fixed on 2021/11/10 00:50
Subsystems: net
[Documentation on labels]
Fix commit: a7150e382267 Revert "tcp: Reset tcp connections in SYN-SENT state"
First crash: 1161d, last: 1160d
Cause bisection: introduced by (bisect log) :
commit 997acaf6b4b59c6a9c259740312a69ea549cc684
Author: Mark Rutland <mark.rutland@arm.com>
Date: Mon Jan 11 15:37:07 2021 +0000

  lockdep: report broken irq restoration

Crash: WARNING in corrupted (log)
Repro: C syz .config
  
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-49 divide error in __tcp_select_window 2 2494d 2494d 0/3 closed as invalid on 2019/01/01 20:10
upstream divide error in __tcp_select_window net C done 1119 1294d 1300d 19/28 fixed on 2021/03/10 01:48

Sample crash report:
divide error: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 8426 Comm: syz-executor478 Not tainted 5.12.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__tcp_select_window+0x56d/0xad0 net/ipv4/tcp_output.c:3015
Code: 44 89 ff e8 d5 cd f0 f9 45 39 e7 0f 8d 20 ff ff ff e8 f7 c7 f0 f9 44 89 e3 e9 13 ff ff ff e8 ea c7 f0 f9 44 89 e0 44 89 e3 99 <f7> 7c 24 04 29 d3 e9 fc fe ff ff e8 d3 c7 f0 f9 41 f7 dc bf 1f 00
RSP: 0018:ffffc9000184fac0 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff87832e76 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff87832e14 R11: 0000000000000000 R12: 0000000000000000
R13: 1ffff92000309f5c R14: 0000000000000000 R15: 0000000000000000
FS:  00000000023eb300(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc2b5f426c0 CR3: 000000001c5cf000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 tcp_select_window net/ipv4/tcp_output.c:264 [inline]
 __tcp_transmit_skb+0xa82/0x38f0 net/ipv4/tcp_output.c:1351
 tcp_transmit_skb net/ipv4/tcp_output.c:1423 [inline]
 tcp_send_active_reset+0x475/0x8e0 net/ipv4/tcp_output.c:3449
 tcp_disconnect+0x15a9/0x1e60 net/ipv4/tcp.c:2955
 inet_shutdown+0x260/0x430 net/ipv4/af_inet.c:905
 __sys_shutdown_sock net/socket.c:2189 [inline]
 __sys_shutdown_sock net/socket.c:2183 [inline]
 __sys_shutdown+0xf1/0x1b0 net/socket.c:2201
 __do_sys_shutdown net/socket.c:2209 [inline]
 __se_sys_shutdown net/socket.c:2207 [inline]
 __x64_sys_shutdown+0x50/0x70 net/socket.c:2207
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x43ef39
Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff9ef5fe08 EFLAGS: 00000246 ORIG_RAX: 0000000000000030
RAX: ffffffffffffffda RBX: 0000000000400488 RCX: 000000000043ef39
RDX: 000000000043ef39 RSI: 0000000000000001 RDI: 0000000000000003
RBP: 0000000000402f20 R08: 0000000000400488 R09: 0000000000400488
R10: 0000000000400488 R11: 0000000000000246 R12: 0000000000402fb0
R13: 0000000000000000 R14: 00000000004ac018 R15: 0000000000400488
Modules linked in:
---[ end trace 8d7a55047d07ab8a ]---
RIP: 0010:__tcp_select_window+0x56d/0xad0 net/ipv4/tcp_output.c:3015
Code: 44 89 ff e8 d5 cd f0 f9 45 39 e7 0f 8d 20 ff ff ff e8 f7 c7 f0 f9 44 89 e3 e9 13 ff ff ff e8 ea c7 f0 f9 44 89 e0 44 89 e3 99 <f7> 7c 24 04 29 d3 e9 fc fe ff ff e8 d3 c7 f0 f9 41 f7 dc bf 1f 00
RSP: 0018:ffffc9000184fac0 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff87832e76 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff87832e14 R11: 0000000000000000 R12: 0000000000000000
R13: 1ffff92000309f5c R14: 0000000000000000 R15: 0000000000000000
FS:  00000000023eb300(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc2b5f426c0 CR3: 000000001c5cf000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/04/08 19:38 net-next-old 3cd52c1e32fe 6a81331a .config console log report syz C ci-upstream-net-kasan-gce divide error in __tcp_select_window
2021/04/09 20:47 net-next-old 4438669eb703 6a81331a .config console log report info ci-upstream-net-kasan-gce divide error in __tcp_select_window
2021/04/08 19:15 net-next-old 3cd52c1e32fe 6a81331a .config console log report info ci-upstream-net-kasan-gce divide error in __tcp_select_window
2021/04/10 01:41 linux-next e99d8a849517 6a81331a .config console log report info ci-upstream-linux-next-kasan-gce-root divide error in __tcp_select_window
* Struck through repros no longer work on HEAD.