syzbot


WARNING in tcp_enter_loss (3)

Status: internal: reported C repro on 2022/01/06 17:42
Reported-by: syzbot+@syzkaller.appspotmail.com
Fix commit: 0c175da7b037 tcp: prohibit TCP_REPAIR_OPTIONS if data was already sent
Patched on: [ci-qemu-upstream ci-qemu-upstream-386 ci-qemu2-arm32 ci-qemu2-arm64 ci-qemu2-arm64-compat ci-qemu2-arm64-mte ci-upstream-bpf-kasan-gce ci-upstream-bpf-next-kasan-gce ci-upstream-gce-arm64 ci-upstream-gce-leak ci-upstream-kasan-gce ci-upstream-kasan-gce-386 ci-upstream-kasan-gce-root ci-upstream-kasan-gce-selinux-root ci-upstream-kasan-gce-smack-root ci-upstream-kmsan-gce ci-upstream-kmsan-gce-386 ci-upstream-linux-next-kasan-gce-root ci-upstream-net-kasan-gce ci-upstream-net-this-kasan-gce ci2-upstream-fs ci2-upstream-kcsan-gce ci2-upstream-usb], missing on: [ci-qemu2-riscv64]
First crash: 394d, last: 98d

Cause bisection: the issue happens on the oldest tested release (bisect log)
Crash: WARNING in tcp_enter_loss (log)
Repro: C syz .config
similar bugs (4):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in tcp_enter_loss 1 1889d 1884d 0/24 closed as invalid on 2018/02/13 19:39
linux-4.19 WARNING in tcp_enter_loss C error 1 393d 393d 0/1 upstream: reported C repro on 2022/01/07 14:26
android-49 WARNING in tcp_enter_loss C 4 1746d 1393d 0/3 public: reported C repro on 2019/04/14 00:00
upstream WARNING in tcp_enter_loss (2) C done unreliable 4 1740d 1790d 16/24 fixed on 2020/02/18 10:28

Sample crash report:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 3601 at net/ipv4/tcp_input.c:2132 tcp_enter_loss+0xf86/0x14b0 net/ipv4/tcp_input.c:2145
Modules linked in:
CPU: 0 PID: 3601 Comm: strace-static-x Not tainted 6.1.0-rc2-syzkaller-00105-gb229b6ca5abb #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/11/2022
RIP: 0010:tcp_timeout_mark_lost net/ipv4/tcp_input.c:2132 [inline]
RIP: 0010:tcp_enter_loss+0xf86/0x14b0 net/ipv4/tcp_input.c:2145
Code: 41 5d 41 5e 41 5f 5d c3 e8 17 31 be f8 e9 13 fc ff ff e8 0d 31 be f8 31 ed eb b0 e8 04 31 be f8 e9 ac f9 ff ff e8 fa 30 be f8 <0f> 0b e9 f6 f8 ff ff e8 ee 30 be f8 0f 0b e9 7a fc ff ff 48 8b 4c
RSP: 0018:ffffc900000079a8 EFLAGS: 00010246
RAX: ffffffff88cb7516 RBX: 0000000000000011 RCX: ffff8880218457c0
RDX: 0000000000000101 RSI: 0000000000000009 RDI: 0000000000000011
RBP: 0000000000000009 R08: ffffffff88cb6e06 R09: ffffffff88d1f216
R10: 0000000000000002 R11: ffff8880218457c0 R12: ffff8880738a954c
R13: ffff8880738a8c00 R14: 1ffff110039bf8a6 R15: dffffc0000000000
FS:  0000000000d96340(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe39b338718 CR3: 000000001f8ab000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 tcp_retransmit_timer+0x18c4/0x2890 net/ipv4/tcp_timer.c:503
 tcp_write_timer+0x176/0x280 net/ipv4/tcp_timer.c:637
 call_timer_fn+0xf5/0x210 kernel/time/timer.c:1474
 expire_timers kernel/time/timer.c:1519 [inline]
 __run_timers+0x76a/0x980 kernel/time/timer.c:1790
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1803
 __do_softirq+0x277/0x75b kernel/softirq.c:571
 __irq_exit_rcu+0xec/0x170 kernel/softirq.c:650
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:662
 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1107
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649
RIP: 0010:stack_trace_consume_entry+0xd2/0x270 kernel/stacktrace.c:93
Code: 49 89 f5 4d 89 c6 e8 2d 45 67 00 4d 89 f0 4c 8b 0c 24 4c 89 ee 48 ba 00 00 00 00 00 fc ff df 48 8b 1b 45 8d 70 01 41 8a 04 17 <84> c0 0f 85 2c 01 00 00 45 89 31 4a 8d 1c c3 48 89 d8 48 c1 e8 03
RSP: 0018:ffffc90003c1f4f0 EFLAGS: 00000246
RAX: 1ffff92000783e00 RBX: ffffc90003c1f6d0 RCX: ffffffff8f74e000
RDX: dffffc0000000000 RSI: ffffffff8830ab24 RDI: ffffc90003c1f62c
RBP: ffffc90003c1f628 R08: 0000000000000007 R09: ffffc90003c1f630
R10: fffff52000783eb4 R11: 1ffff92000783eb2 R12: 1ffff92000783ec5
R13: 1ffff92000783ec5 R14: 0000000000000008 R15: 1ffff92000783ec6
 arch_stack_walk+0x106/0x140 arch/x86/kernel/stacktrace.c:27
 stack_trace_save+0x12d/0x1f0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4c/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:511
 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1724 [inline]
 slab_free_freelist_hook+0x12e/0x1a0 mm/slub.c:1750
 slab_free mm/slub.c:3661 [inline]
 kmem_cache_free+0x94/0x1d0 mm/slub.c:3683
 netlink_recvmsg+0x5c1/0x10f0 net/netlink/af_netlink.c:1998
 ____sys_recvmsg+0x285/0x530
 ___sys_recvmsg net/socket.c:2743 [inline]
 __sys_recvmsg+0x294/0x390 net/socket.c:2773
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x46c083
Code: c7 c2 b8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb bf 0f 1f 44 00 00 64 8b 04 25 18 00 00 00 85 c0 75 14 b8 2f 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 55 c3 0f 1f 40 00 48 83 ec 28 89 54 24 1c 48
RSP: 002b:00007fff768fbf58 EFLAGS: 00000246 ORIG_RAX: 000000000000002f
RAX: ffffffffffffffda RBX: 0000000000000014 RCX: 000000000046c083
RDX: 0000000000000040 RSI: 00007fff768fbfa0 RDI: 0000000000000003
RBP: 0000000000562195 R08: 0000000000562195 R09: 0000000000562195
R10: 000000000045be50 R11: 0000000000000246 R12: 000000000045bfc0
R13: 0000000000006ffb R14: 0000000000000040 R15: 0000000000000000
 </TASK>
----------------
Code disassembly (best guess):
   0:	49 89 f5             	mov    %rsi,%r13
   3:	4d 89 c6             	mov    %r8,%r14
   6:	e8 2d 45 67 00       	callq  0x674538
   b:	4d 89 f0             	mov    %r14,%r8
   e:	4c 8b 0c 24          	mov    (%rsp),%r9
  12:	4c 89 ee             	mov    %r13,%rsi
  15:	48 ba 00 00 00 00 00 	movabs $0xdffffc0000000000,%rdx
  1c:	fc ff df
  1f:	48 8b 1b             	mov    (%rbx),%rbx
  22:	45 8d 70 01          	lea    0x1(%r8),%r14d
  26:	41 8a 04 17          	mov    (%r15,%rdx,1),%al
* 2a:	84 c0                	test   %al,%al <-- trapping instruction
  2c:	0f 85 2c 01 00 00    	jne    0x15e
  32:	45 89 31             	mov    %r14d,(%r9)
  35:	4a 8d 1c c3          	lea    (%rbx,%r8,8),%rbx
  39:	48 89 d8             	mov    %rbx,%rax
  3c:	48 c1 e8 03          	shr    $0x3,%rax

Fix bisection attempts:
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets Title
ci-upstream-kasan-gce 2022/07/12 17:25 upstream 72a8e05d4f66 6acc789a .config console log report syz C
ci-upstream-kasan-gce 2022/06/09 08:14 upstream 6bfb56e93bce 6acc789a .config console log report syz C
ci-upstream-kasan-gce 2022/05/09 23:06 upstream 9be9ed2612b5 6acc789a .config console log report syz C
ci-upstream-kasan-gce 2022/04/06 18:43 upstream 3e732ebf7316 6acc789a .config console log report syz C
ci-upstream-kasan-gce 2022/03/07 18:23 upstream ffb217a13a2e 6acc789a .config console log report syz C
ci-upstream-kasan-gce 2022/02/05 18:01 upstream fbc04bf01a8d 6acc789a .config console log report syz C
* Struck through repros no longer work on HEAD.
Crashes (7):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets Title
ci-upstream-kasan-gce-smack-root 2022/10/30 11:42 upstream b229b6ca5abb 2a71366b .config strace log report syz C [disk image] [vmlinux] [kernel image] WARNING in tcp_enter_loss
ci-upstream-kasan-gce-root 2022/08/22 13:47 upstream e3f259d33c0e 26a13b38 .config strace log report syz C WARNING in tcp_enter_loss
ci-upstream-kasan-gce 2022/08/12 18:42 upstream 7ebfc85e2cd7 402cd70d .config strace log report syz C WARNING in tcp_enter_loss
ci-upstream-kasan-gce 2022/01/06 17:41 upstream 75acfdb6fd92 6acc789a .config console log report syz C WARNING in tcp_enter_loss
ci-upstream-net-this-kasan-gce 2022/08/12 18:25 net 7ebfc85e2cd7 402cd70d .config strace log report syz C WARNING in tcp_enter_loss
ci-upstream-net-kasan-gce 2022/08/12 18:25 net-next 7ebfc85e2cd7 402cd70d .config strace log report syz C WARNING in tcp_enter_loss
ci-upstream-linux-next-kasan-gce-root 2022/10/05 09:30 linux-next aaa11ce2ffc8 eab8f949 .config strace log report syz C [disk image] [vmlinux] WARNING in tcp_enter_loss
* Struck through repros no longer work on HEAD.