syzbot


WARNING in subflow_data_ready (4)

Status: upstream: reported C repro on 2025/08/20 12:41
Subsystems: mptcp
[Documentation on labels]
Reported-by: syzbot+0ff6b771b4f7a5bce83b@syzkaller.appspotmail.com
First crash: 112d, last: 24m
Discussions (2)
Title Replies (including bot) Last reply
[syzbot] [mptcp?] WARNING in subflow_data_ready (4) 0 (4) 2025/11/27 07:45
[syzbot] Monthly mptcp report (Oct 2025) 0 (1) 2025/10/09 16:31
Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in subflow_data_ready mptcp -1 42 692d 776d 25/29 fixed on 2024/01/20 21:18
upstream WARNING in subflow_data_ready (3) mptcp -1 1 193d 193d 0/29 closed as invalid on 2025/06/27 12:28
linux-6.1 WARNING in subflow_data_ready origin:lts-only -1 C unreliable 6 554d 699d 0/3 upstream: reported C repro on 2024/01/11 08:07
upstream WARNING in subflow_data_ready (2) mptcp -1 C done 9 668d 686d 0/29 auto-obsoleted due to no activity on 2024/05/21 09:30
linux-6.6 WARNING in subflow_data_ready -1 C 2 2h12m 5h28m 0/2 upstream: reported C repro on 2025/12/10 13:17
Last patch testing requests (2)
Created Duration User Patch Repo Result
2025/11/27 07:45 15m pabeni@redhat.com patch git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 8e621c9a3375 report log
2025/11/26 18:25 23m pabeni@redhat.com patch git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git main OK log

Sample crash report:
------------[ cut here ]------------
WARNING: net/mptcp/subflow.c:1527 at subflow_data_ready+0x40b/0x790 net/mptcp/subflow.c:1527, CPU#1: ksoftirqd/1/23
Modules linked in:
CPU: 1 UID: 0 PID: 23 Comm: ksoftirqd/1 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:subflow_data_ready+0x40b/0x790 net/mptcp/subflow.c:1527
Code: 89 ee e8 d8 5b 5e f6 40 84 ed 75 21 e8 8e 61 5e f6 44 89 fe bf 07 00 00 00 e8 21 5c 5e f6 41 83 ff 07 74 09 e8 76 61 5e f6 90 <0f> 0b 90 e8 6d 61 5e f6 48 89 df e8 f5 ac ff ff 31 ff 89 c5 89 c6
RSP: 0018:ffffc900001d7308 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff8880351e3fc0 RCX: ffffffff8b5ff51f
RDX: ffff88801dafdb80 RSI: ffffffff8b5ff52a RDI: 0000000000000005
RBP: 0000000000000000 R08: 0000000000000005 R09: 0000000000000007
R10: 0000000000000004 R11: ffff88801dafe6b0 R12: ffff888078d38000
R13: 1ffff9200003ae61 R14: ffff88807f26c400 R15: 0000000000000004
FS:  0000000000000000(0000) GS:ffff888124a0e000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000023b000 CR3: 000000007567c000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 tcp_data_ready+0x114/0x5a0 net/ipv4/tcp_input.c:5371
 tcp_data_queue+0x1ac2/0x4ff0 net/ipv4/tcp_input.c:5461
 tcp_rcv_state_process+0xfb6/0x6540 net/ipv4/tcp_input.c:7185
 tcp_v4_do_rcv+0x68e/0x10a0 net/ipv4/tcp_ipv4.c:1904
 tcp_v4_rcv+0x3077/0x4db0 net/ipv4/tcp_ipv4.c:2324
 ip_protocol_deliver_rcu+0xba/0x4c0 net/ipv4/ip_input.c:207
 ip_local_deliver_finish+0x3f2/0x720 net/ipv4/ip_input.c:241
 NF_HOOK include/linux/netfilter.h:318 [inline]
 NF_HOOK include/linux/netfilter.h:312 [inline]
 ip_local_deliver+0x18e/0x1f0 net/ipv4/ip_input.c:262
 dst_input include/net/dst.h:474 [inline]
 ip_rcv_finish net/ipv4/ip_input.c:453 [inline]
 NF_HOOK include/linux/netfilter.h:318 [inline]
 NF_HOOK include/linux/netfilter.h:312 [inline]
 ip_rcv+0x2e0/0x600 net/ipv4/ip_input.c:573
 __netif_receive_skb_one_core+0x197/0x1e0 net/core/dev.c:6137
 __netif_receive_skb+0x1d/0x160 net/core/dev.c:6250
 process_backlog+0x4a2/0x1650 net/core/dev.c:6602
 __napi_poll.constprop.0+0xb3/0x540 net/core/dev.c:7666
 napi_poll net/core/dev.c:7729 [inline]
 net_rx_action+0x9f9/0xfa0 net/core/dev.c:7881
 handle_softirqs+0x219/0x950 kernel/softirq.c:622
 run_ksoftirqd kernel/softirq.c:1063 [inline]
 run_ksoftirqd+0x3a/0x60 kernel/softirq.c:1055
 smpboot_thread_fn+0x3f7/0xae0 kernel/smpboot.c:160
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
 </TASK>

Crashes (259):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/12/09 03:25 upstream c2f2b01b74be d1b870e1 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in subflow_data_ready
2025/12/02 08:06 upstream 1d18101a644e d1b870e1 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in subflow_data_ready
2025/11/20 20:57 upstream 8e621c9a3375 2cc4c24a .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in subflow_data_ready
2025/12/10 18:18 upstream 0048fbb4011e d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in subflow_data_ready
2025/12/10 13:26 upstream c9b47175e913 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in subflow_data_ready
2025/12/09 19:31 upstream cb015814f8b6 d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in subflow_data_ready
2025/12/09 14:57 upstream cb015814f8b6 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in subflow_data_ready
2025/12/09 01:59 upstream a110f942672c d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in subflow_data_ready
2025/12/08 23:48 upstream c2f2b01b74be d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in subflow_data_ready
2025/12/08 15:19 upstream ba65a4e7120a d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in subflow_data_ready
2025/12/08 09:06 upstream ba65a4e7120a d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in subflow_data_ready
2025/12/08 08:04 upstream ba65a4e7120a d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in subflow_data_ready
2025/12/08 01:53 upstream 37bb2e7217b0 d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in subflow_data_ready
2025/12/07 09:14 upstream cc3ee4ba57b7 d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in subflow_data_ready
2025/12/07 07:16 upstream cc3ee4ba57b7 d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in subflow_data_ready
2025/12/07 07:11 upstream cc3ee4ba57b7 d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in subflow_data_ready
2025/12/06 21:06 upstream 416f99c3b16f d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in subflow_data_ready
2025/12/06 16:19 upstream 416f99c3b16f d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in subflow_data_ready
2025/12/06 03:19 upstream 51d90a15fedf d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in subflow_data_ready
2025/12/05 15:48 upstream 2061f18ad76e d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in subflow_data_ready
2025/12/05 09:42 upstream aa833fc394ba d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in subflow_data_ready
2025/12/05 04:14 upstream 559e608c4655 d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in subflow_data_ready
2025/12/05 00:47 upstream aa833fc394ba d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in subflow_data_ready
2025/12/04 15:51 upstream 8f7aa3d3c732 d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in subflow_data_ready
2025/12/04 14:21 upstream 8f7aa3d3c732 d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in subflow_data_ready
2025/12/04 10:39 upstream 8f7aa3d3c732 d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in subflow_data_ready
2025/12/04 09:23 upstream 8f7aa3d3c732 d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in subflow_data_ready
2025/12/04 06:28 upstream 8f7aa3d3c732 d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in subflow_data_ready
2025/12/04 02:34 upstream a619fe35ab41 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in subflow_data_ready
2025/12/03 05:20 upstream 3f9f0252130e d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in subflow_data_ready
2025/12/03 02:34 upstream d61f1cc5db79 d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in subflow_data_ready
2025/12/02 07:00 upstream 1d18101a644e d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in subflow_data_ready
2025/12/01 16:04 upstream 7d0a66e4bb90 d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in subflow_data_ready
2025/12/01 13:30 upstream 7d0a66e4bb90 d1b870e1 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in subflow_data_ready
2025/12/07 13:48 upstream 50471f8b7371 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 WARNING in subflow_data_ready
2025/12/08 03:00 upstream 37bb2e7217b0 d1b870e1 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in subflow_data_ready
2025/12/05 10:58 upstream 2061f18ad76e d1b870e1 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in subflow_data_ready
2025/12/04 07:58 upstream cc25df3e2e22 d1b870e1 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in subflow_data_ready
2025/12/01 19:10 upstream 7d0a66e4bb90 d1b870e1 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in subflow_data_ready
2025/12/01 14:43 upstream 7d0a66e4bb90 d1b870e1 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in subflow_data_ready
2025/11/30 23:21 upstream e69c7c175115 d1b870e1 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in subflow_data_ready
2025/08/20 11:14 upstream b19a97d57c15 79512909 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in subflow_data_ready
2025/12/08 17:30 upstream c2f2b01b74be d1b870e1 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in subflow_data_ready
2025/12/05 17:38 upstream 2061f18ad76e d1b870e1 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in subflow_data_ready
2025/11/25 08:59 upstream ac3fd01e4c1e 64219f15 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64 WARNING in subflow_data_ready
2025/12/10 11:51 net 5ace7ef87f05 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING in subflow_data_ready
2025/12/10 10:27 net 5ace7ef87f05 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING in subflow_data_ready
2025/12/10 00:22 net 186468c67fc6 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING in subflow_data_ready
2025/12/09 06:30 net 0373d5c387f2 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING in subflow_data_ready
2025/12/02 19:42 net 108f9405ce81 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING in subflow_data_ready
2025/12/02 12:39 net e5235eb6cfe0 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING in subflow_data_ready
2025/12/01 09:26 net e5235eb6cfe0 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING in subflow_data_ready
2025/12/01 08:02 net e5235eb6cfe0 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING in subflow_data_ready
2025/12/01 01:32 net e5235eb6cfe0 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING in subflow_data_ready
2025/11/30 22:20 net e5235eb6cfe0 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING in subflow_data_ready
2025/11/30 18:28 net e5235eb6cfe0 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce WARNING in subflow_data_ready
2025/12/02 22:50 net-next 31a3ed492dd4 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce WARNING in subflow_data_ready
2025/12/09 09:33 linux-next c75caf76ed86 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in subflow_data_ready
2025/12/06 05:35 linux-next 6987d58a9cbc d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in subflow_data_ready
2025/12/02 11:28 linux-next 7d31f578f323 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in subflow_data_ready
2025/12/01 21:18 linux-next 7d31f578f323 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in subflow_data_ready
2025/11/26 13:59 linux-next 663d0d1af3fa d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in subflow_data_ready
2025/12/08 11:24 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 05c93f3395ed d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in subflow_data_ready
2025/12/03 06:28 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 05c93f3395ed d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in subflow_data_ready
* Struck through repros no longer work on HEAD.