WARNING in __netif_receive_skb_core

Status: upstream: reported C repro on 2026/09/15 15:56
Subsystems: can
Labels: prio:low
[Documentation on labels]
Reported-by: syzbot+1aae11dc8d42ec1a87ec@syzkaller.appspotmail.com
First crash: 46d, last: 24d
Cause bisection: failed (error log, bisect log)
  
▶ ▼ ✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision
ca584b60 assessment-security DenialOfService: ❌ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ ❓ WARNING in __netif_receive_skb_core 2026/09/15 02:21 2026/09/15 02:21 2026/09/15 03:19 81a27d1a
▶ ▼ Discussions (2)
Title Replies (including bot) Last reply
[PATCH] can: dev: fix missing skb header initialization in init_can_skb 2 (2) 2026/09/18 17:33
[syzbot] [can?] WARNING in __netif_receive_skb_core 0 (3) 2026/09/17 20:39
▶ ▼ Last patch testing requests (12)
Created Duration User Patch Repo Result
2026/10/30 13:10 23m retest repro git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci job log log
2026/10/30 09:11 24m retest repro upstream no crash job log log
2026/10/30 09:11 26m retest repro upstream no crash job log log
2026/10/30 09:11 26m retest repro upstream no crash job log log
2026/10/30 09:11 24m retest repro upstream no crash job log log
2026/10/30 09:11 23m retest repro git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci no crash job log log
2026/10/20 17:59 19m retest repro upstream no crash job log log
2026/10/20 17:59 18m retest repro upstream no crash job log log
2026/10/20 17:59 19m retest repro upstream no crash job log log
2026/10/20 17:59 19m retest repro upstream no crash job log log
2026/09/17 20:39 5h02m shaunakkdatar@gmail.com patch upstream OK job log log
2026/09/17 20:31 4h49m shaunakkdatar@gmail.com patch upstream OK job log log

Sample crash report:
------------[ cut here ]------------
WARNING: ./include/linux/skbuff.h:3003 at skb_reset_mac_len include/linux/skbuff.h:-1 [inline], CPU#0: kworker/u8:9/1476
WARNING: ./include/linux/skbuff.h:3003 at __netif_receive_skb_core+0x260/0x2b60 net/core/dev.c:6061, CPU#0: kworker/u8:9/1476
Modules linked in:
CPU: 0 UID: 0 PID: 1476 Comm: kworker/u8:9 Not tainted syzkaller #0 PREEMPT 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/14/2026
Workqueue: events_unbound flush_to_ldisc
pstate: 43400005 (nZcv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--)
pc : skb_reset_mac_len include/linux/skbuff.h:-1 [inline]
pc : __netif_receive_skb_core+0x260/0x2b60 net/core/dev.c:6061
lr : skb_reset_mac_len include/linux/skbuff.h:3003 [inline]
lr : __netif_receive_skb_core+0x25c/0x2b60 net/core/dev.c:6061
sp : ffff80008ec37880
x29: ffff80008ec37ac0 x28: ffff700011d86f30 x27: dfff800000000000
x26: 1ffff00011d1bfc0 x25: ffff0000d8ff8000 x24: ffff80008ec37980
x23: ffff0000c93ad880 x22: 0000000000000000 x21: 0000000000000000
x20: 000000000000ffff x19: ffff0000dee54c80 x18: 00000000ffffffff
x17: ffff800125154000 x16: ffff80008ec30000 x15: ffff800084ca2bec
x14: ffff80008b0df2b0 x13: 0000000000000009 x12: 0000000000000000
x11: 0000000009528823 x10: 0000000000000003 x9 : 0000000000000101
x8 : 0000000000000000 x7 : ffff800084d0f334 x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000000 x3 : ffff800084d05aac
x2 : 000000000000ffff x1 : ffff0000c93ad880 x0 : 0000000000000000
Call trace:
 skb_reset_mac_len include/linux/skbuff.h:-1 [inline] (P)
 __netif_receive_skb_core+0x260/0x2b60 net/core/dev.c:6061 (P)
 __netif_receive_skb_one_core+0x70/0x110 net/core/dev.c:6262
 __netif_receive_skb+0x34/0x128 net/core/dev.c:6377
 process_backlog+0x5f4/0x16f8 net/core/dev.c:6728
 __napi_poll+0xb4/0x328 net/core/dev.c:7787
 napi_poll net/core/dev.c:7850 [inline]
 net_rx_action+0x5b0/0xc14 net/core/dev.c:8007
 handle_softirqs+0x2ec/0xd98 kernel/softirq.c:645
 __do_softirq+0x14/0x20 kernel/softirq.c:679
 ____do_softirq+0x14/0x20 arch/arm64/kernel/irq.c:78
 call_on_irq_stack+0x30/0x48 arch/arm64/kernel/entry.S:885
 do_softirq_own_stack+0x20/0x2c arch/arm64/kernel/irq.c:83
 do_softirq+0x90/0xf8 kernel/softirq.c:546
 __local_bh_enable_ip+0x240/0x35c kernel/softirq.c:473
 local_bh_enable include/linux/bottom_half.h:33 [inline]
 netif_rx+0xb4/0xd4 net/core/dev.c:5837
 slcan_bump_err drivers/net/can/slcan/slcan-core.c:448 [inline]
 slcan_bump drivers/net/can/slcan/slcan-core.c:463 [inline]
 slcan_unesc drivers/net/can/slcan/slcan-core.c:476 [inline]
 slcan_receive_buf+0x12f8/0x1a68 drivers/net/can/slcan/slcan-core.c:807
 tty_ldisc_receive_buf+0x12c/0x15c drivers/tty/tty_buffer.c:398
 tty_port_default_receive_buf+0x74/0xac drivers/tty/tty_port.c:37
 receive_buf drivers/tty/tty_buffer.c:452 [inline]
 flush_to_ldisc+0x1d8/0x578 drivers/tty/tty_buffer.c:502
 process_one_work kernel/workqueue.c:3387 [inline]
 process_scheduled_works+0x91c/0x1250 kernel/workqueue.c:3470
 worker_thread+0x798/0xbd0 kernel/workqueue.c:3551
 kthread+0x304/0x3d4 kernel/kthread.c:436
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:838
irq event stamp: 239269
hardirqs last  enabled at (239268): [<ffff8000869a99e0>] __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:219 [inline]
hardirqs last  enabled at (239268): [<ffff8000869a99e0>] _raw_spin_unlock_irq+0x30/0x80 kernel/locking/spinlock.c:229
hardirqs last disabled at (239269): [<ffff8000869841d4>] el1_brk64+0x20/0x54 arch/arm64/kernel/entry-common.c:445
softirqs last  enabled at (239262): [<ffff800084cde728>] local_bh_enable include/linux/bottom_half.h:33 [inline]
softirqs last  enabled at (239262): [<ffff800084cde728>] netif_rx+0xac/0xd4 net/core/dev.c:5837
softirqs last disabled at (239263): [<ffff8000800204c0>] __do_softirq+0x14/0x20 kernel/softirq.c:679
---[ end trace 0000000000000000 ]---

Crashes (97):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/09/14 20:16 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 5445d6419962 924033e8 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in __netif_receive_skb_core
2026/09/24 04:56 upstream 62f4c998b297 0a1606bc .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in __netif_receive_skb_core
2026/09/23 12:09 upstream fe2ec83746e5 abce1216 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in __netif_receive_skb_core
2026/09/22 22:30 upstream c4e9f74da438 3e2106e5 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in __netif_receive_skb_core
2026/09/22 10:31 upstream f0100363d8c3 e12281bd .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in __netif_receive_skb_core
2026/09/22 07:42 upstream f0100363d8c3 e12281bd .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in __netif_receive_skb_core
2026/09/19 22:40 upstream 40288c9206c1 853b104b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in __netif_receive_skb_core
2026/09/18 16:46 upstream 5dd1818b15d9 8d7d05f1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in __netif_receive_skb_core
2026/09/18 11:09 upstream 5dd1818b15d9 8d7d05f1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in __netif_receive_skb_core
2026/09/18 11:08 upstream 5dd1818b15d9 8d7d05f1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in __netif_receive_skb_core
2026/09/17 23:04 upstream 4982d3552a3b 95928915 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in __netif_receive_skb_core
2026/09/17 22:45 upstream 4982d3552a3b 95928915 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in __netif_receive_skb_core
2026/09/17 22:41 upstream 4982d3552a3b 95928915 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in __netif_receive_skb_core
2026/09/17 22:40 upstream 4982d3552a3b 95928915 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in __netif_receive_skb_core
2026/09/14 22:05 upstream 704340f1cd0d 924033e8 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in __netif_receive_skb_core
2026/09/14 21:23 upstream 704340f1cd0d 924033e8 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in __netif_receive_skb_core
2026/09/14 21:18 upstream 704340f1cd0d 924033e8 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in __netif_receive_skb_core
2026/09/14 20:44 upstream 704340f1cd0d 924033e8 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in __netif_receive_skb_core
2026/09/14 20:09 upstream 704340f1cd0d 924033e8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in __netif_receive_skb_core
2026/09/14 20:09 upstream 704340f1cd0d 924033e8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in __netif_receive_skb_core
2026/09/14 19:50 upstream 704340f1cd0d 924033e8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in __netif_receive_skb_core
2026/09/14 19:50 upstream 704340f1cd0d 924033e8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in __netif_receive_skb_core
2026/09/14 19:47 upstream 704340f1cd0d 924033e8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in __netif_receive_skb_core
2026/10/05 22:56 upstream 67f0943b394d 1995e6c7 .config console log report syz / log [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __netif_receive_skb_core
2026/10/05 21:48 upstream 67f0943b394d 1995e6c7 .config console log report syz / log [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __netif_receive_skb_core
2026/10/05 20:43 upstream 67f0943b394d 1995e6c7 .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __netif_receive_skb_core
2026/10/05 14:27 upstream a90ee4305c4a 1995e6c7 .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __netif_receive_skb_core
2026/10/05 09:11 upstream a90ee4305c4a 57bbd979 .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __netif_receive_skb_core
2026/09/22 06:34 upstream f0100363d8c3 e12281bd .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in __netif_receive_skb_core
2026/09/17 21:21 upstream 4982d3552a3b 4a607247 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __netif_receive_skb_core
2026/09/17 21:21 upstream 4982d3552a3b 4a607247 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __netif_receive_skb_core
2026/09/14 20:22 upstream 704340f1cd0d 924033e8 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __netif_receive_skb_core
2026/09/14 20:22 upstream 704340f1cd0d 924033e8 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in __netif_receive_skb_core
2026/10/06 15:37 upstream 2c3418fffa9d f7710056 .config console log report syz / log [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in __netif_receive_skb_core
2026/10/06 14:33 upstream 2c3418fffa9d f7710056 .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in __netif_receive_skb_core
2026/10/06 12:20 upstream 2c3418fffa9d f7710056 .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in __netif_receive_skb_core
2026/10/06 11:15 upstream 2c3418fffa9d f7710056 .config console log report syz / log [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in __netif_receive_skb_core
2026/10/06 08:05 upstream 2c3418fffa9d f7710056 .config console log report syz / log [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in __netif_receive_skb_core
2026/09/19 19:40 upstream 50d05c7c76c9 853b104b .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in __netif_receive_skb_core
2026/09/17 21:03 upstream 50d05c7c76c9 4a607247 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in __netif_receive_skb_core
2026/09/17 21:03 upstream 50d05c7c76c9 4a607247 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in __netif_receive_skb_core
2026/09/17 10:55 upstream 50d05c7c76c9 95928915 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in __netif_receive_skb_core
2026/09/14 19:43 upstream 50d05c7c76c9 924033e8 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in __netif_receive_skb_core
2026/09/14 19:43 upstream 50d05c7c76c9 924033e8 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in __netif_receive_skb_core
2026/09/14 19:42 upstream 50d05c7c76c9 924033e8 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in __netif_receive_skb_core
2026/09/23 00:33 linux-next a8c591ed6b67 3e2106e5 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in __netif_receive_skb_core
2026/09/17 10:59 linux-next 9d80aa4617b3 95928915 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in __netif_receive_skb_core
2026/09/17 10:57 linux-next 9d80aa4617b3 95928915 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in __netif_receive_skb_core
2026/09/17 10:52 linux-next 9d80aa4617b3 95928915 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in __netif_receive_skb_core
2026/09/14 20:29 linux-next 9d80aa4617b3 924033e8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in __netif_receive_skb_core
2026/09/14 20:26 linux-next 9d80aa4617b3 924033e8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in __netif_receive_skb_core
2026/09/14 20:01 linux-next 9d80aa4617b3 924033e8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in __netif_receive_skb_core
2026/09/22 04:47 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 38872197cae2 e12281bd .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in __netif_receive_skb_core
2026/09/19 19:11 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 38872197cae2 853b104b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in __netif_receive_skb_core
2026/09/17 20:56 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 5445d6419962 95928915 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in __netif_receive_skb_core
2026/09/17 10:51 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 5445d6419962 95928915 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in __netif_receive_skb_core
2026/09/17 10:51 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 5445d6419962 95928915 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in __netif_receive_skb_core
2026/09/14 20:46 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 5445d6419962 924033e8 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in __netif_receive_skb_core
2026/09/14 19:39 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 5445d6419962 924033e8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in __netif_receive_skb_core
2026/09/14 19:39 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 5445d6419962 924033e8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in __netif_receive_skb_core
2026/09/22 13:15 https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master 73ae59e97596 e12281bd .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64-mte WARNING in __netif_receive_skb_core
2026/09/22 13:15 https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master 73ae59e97596 e12281bd .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64-mte WARNING in __netif_receive_skb_core
2026/09/21 08:19 https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master 73ae59e97596 853b104b .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64-compat WARNING in __netif_receive_skb_core
2026/09/19 21:34 https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master 73ae59e97596 853b104b .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64 WARNING in __netif_receive_skb_core
2026/09/18 19:51 https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master 73ae59e97596 853b104b .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64-mte WARNING in __netif_receive_skb_core
2026/09/17 21:25 https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master 73ae59e97596 4a607247 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64-mte WARNING in __netif_receive_skb_core
2026/09/14 21:27 https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master 73ae59e97596 924033e8 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64-mte WARNING in __netif_receive_skb_core
2026/09/14 21:26 https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux master 73ae59e97596 924033e8 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-arm64-mte WARNING in __netif_receive_skb_core
* Struck through repros no longer work on HEAD.