general protection fault in keyspan_break_ctl

Status: upstream: reported C repro on 2026/08/27 18:53
Subsystems: usb
Labels: prio:high
[Documentation on labels]
Reported-by: syzbot+473d7477c523b41d4046@syzkaller.appspotmail.com
Fix commit: ae0e61d95677 USB: serial: fix ioctl hangup race
Patched on: [ci-qemu-gce-upstream-auto ci-qemu-upstream ci-qemu-upstream-386 ci-qemu2-arm32 ci-qemu2-arm64 ci-qemu2-arm64-compat ci-qemu2-arm64-mte ci-qemu2-riscv64 ci-snapshot-upstream-root ci-upstream-gce-arm64 ci-upstream-gce-leak ci-upstream-kasan-badwrites-root 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-linux-next-kasan-gce-root ci-upstream-net-kasan-gce ci-upstream-net-this-kasan-gce ci-upstream-rust-kasan-gce ci2-upstream-fs ci2-upstream-kcsan-gce ci2-upstream-usb], missing on: [ci-qemu-native-arm64-kvm ci-upstream-bpf-kasan-gce ci-upstream-bpf-next-kasan-gce ci-upstream-kmsan-gce-386-root ci-upstream-kmsan-gce-root]
First crash: 51d, last: 11d
▶ ▼ ✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision
ba2efeaa assessment-security DenialOfService: ✅ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ✅ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ ❓ general protection fault in keyspan_break_ctl 2026/08/26 00:00 2026/08/26 00:00 2026/08/26 00:08 ee98d2fd
▶ ▼ Discussions (3)
Title Replies (including bot) Last reply
[PATCH] USB: serial: fix ioctl hangup race 1 (1) 2026/09/03 16:31
[syzbot] [usb?] general protection fault in keyspan_break_ctl 1 (7) 2026/09/03 14:55
[PATCH v2 0/2] tty: fix break race 4 (4) 2026/09/03 06:22
▶ ▼ Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 BUG: unable to handle kernel paging request in keyspan_break_ctl 8 syz, C 5 3d17h 3d19h 0/3 upstream: reported C repro on 2026/10/11 16:26
linux-6.6 general protection fault in keyspan_break_ctl 2 syz, C 7 3d18h 4d10h 0/2 upstream: reported C repro on 2026/10/11 02:07
▶ ▼ Last patch testing requests (4)
Created Duration User Patch Repo Result
2026/09/03 03:42 19m adrianox@gmail.com patch upstream OK job log log
2026/09/03 03:25 14m adrianox@gmail.com upstream report job log log
2026/09/03 02:25 14m adrianox@gmail.com patch upstream report job log log
2026/08/28 01:28 22m kartikey406@gmail.com patch upstream error job log

Sample crash report:
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000013: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000098-0x000000000000009f]
CPU: 0 UID: 0 PID: 6021 Comm: syz.1.18 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:keyspan_break_ctl+0x8e/0xe0 drivers/usb/serial/keyspan.c:608
Code: ff ff ff e8 74 d6 41 fa 83 fb ff 48 b8 00 00 00 00 00 fc ff df 49 8d bc 24 9c 00 00 00 0f 94 c3 48 89 fa 0f b6 db 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 1d 41
RSP: 0018:ffffc90003e37cb0 EFLAGS: 00010203
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff87ca3a0c
RDX: 0000000000000013 RSI: 00000000ffffffff RDI: 000000000000009c
RBP: ffff888027302000 R08: 0000000000000005 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: ffff888056451020 R14: ffff8880564510c8 R15: 0000000000000007
FS:  00005555833a3500(0000) GS:ffff8880d5b5c000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000564b17200168 CR3: 00000000243e6000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 serial_break+0xcb/0x160 drivers/usb/serial/usb-serial.c:538
 send_break drivers/tty/tty_io.c:2458 [inline]
 send_break+0x2ec/0x370 drivers/tty/tty_io.c:2441
 tty_ioctl+0xa2c/0x1640 drivers/tty/tty_io.c:2733
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl fs/ioctl.c:583 [inline]
 __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1d0119e159
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffc070cc2c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f1d01425fa0 RCX: 00007f1d0119e159
RDX: 0000000000000007 RSI: 0000000000005425 RDI: 0000000000000004
RBP: 00007f1d0123503b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1d01425fac R14: 00007f1d01425fa0 R15: 00007f1d01425fa0
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:keyspan_break_ctl+0x8e/0xe0 drivers/usb/serial/keyspan.c:608
Code: ff ff ff e8 74 d6 41 fa 83 fb ff 48 b8 00 00 00 00 00 fc ff df 49 8d bc 24 9c 00 00 00 0f 94 c3 48 89 fa 0f b6 db 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 1d 41
RSP: 0018:ffffc90003e37cb0 EFLAGS: 00010203
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff87ca3a0c
RDX: 0000000000000013 RSI: 00000000ffffffff RDI: 000000000000009c
RBP: ffff888027302000 R08: 0000000000000005 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: ffff888056451020 R14: ffff8880564510c8 R15: 0000000000000007
FS:  00005555833a3500(0000) GS:ffff8880d5e5c000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fdde75aedc0 CR3: 00000000243e6000 CR4: 0000000000352ef0
----------------
Code disassembly (best guess), 2 bytes skipped:
   0:	ff                   	ljmp   (bad)
   1:	e8 74 d6 41 fa       	call   0xfa41d67a
   6:	83 fb ff             	cmp    $0xffffffff,%ebx
   9:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  10:	fc ff df
  13:	49 8d bc 24 9c 00 00 	lea    0x9c(%r12),%rdi
  1a:	00
  1b:	0f 94 c3             	sete   %bl
  1e:	48 89 fa             	mov    %rdi,%rdx
  21:	0f b6 db             	movzbl %bl,%ebx
  24:	48 c1 ea 03          	shr    $0x3,%rdx
* 28:	0f b6 14 02          	movzbl (%rdx,%rax,1),%edx <-- trapping instruction
  2c:	48 89 f8             	mov    %rdi,%rax
  2f:	83 e0 07             	and    $0x7,%eax
  32:	83 c0 03             	add    $0x3,%eax
  35:	38 d0                	cmp    %dl,%al
  37:	7c 04                	jl     0x3d
  39:	84 d2                	test   %dl,%dl
  3b:	75 1d                	jne    0x5a
  3d:	41                   	rex.B

Crashes (43):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/09/12 10:55 upstream 3026c6e4f223 70a60e12 .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in keyspan_break_ctl
2026/09/04 20:18 upstream bc35965f6940 44dda43b .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 general protection fault in keyspan_break_ctl
2026/09/03 15:24 upstream 940de590b839 d2e5fb95 .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 general protection fault in keyspan_break_ctl
2026/09/03 14:55 upstream 940de590b839 d2e5fb95 .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 general protection fault in keyspan_break_ctl
2026/10/03 14:22 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci fe98fb51bf62 57bbd979 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 BUG: unable to handle kernel paging request in keyspan_break_ctl
2026/10/03 08:32 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci fe98fb51bf62 57bbd979 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 BUG: unable to handle kernel paging request in keyspan_break_ctl
2026/10/03 06:02 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci fe98fb51bf62 57bbd979 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 BUG: unable to handle kernel paging request in keyspan_break_ctl
2026/08/25 08:47 upstream 818bebeb63dd 614e416a .config console log report syz / log [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in keyspan_break_ctl
2026/08/25 01:27 upstream 818bebeb63dd 614e416a .config console log report syz / log [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in keyspan_break_ctl
2026/08/25 01:09 upstream 818bebeb63dd 614e416a .config console log report syz / log [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in keyspan_break_ctl
2026/08/25 04:58 linux-next 4b18edbd8e70 23caa175 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce general protection fault in keyspan_break_ctl
2026/08/25 01:28 linux-next 4b18edbd8e70 23caa175 .config strace log report syz / log [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce general protection fault in keyspan_break_ctl
2026/09/15 17:08 upstream 587858367581 81a27d1a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root general protection fault in keyspan_break_ctl
2026/09/15 17:06 upstream 587858367581 81a27d1a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root general protection fault in keyspan_break_ctl
2026/09/15 17:05 upstream 587858367581 81a27d1a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root general protection fault in keyspan_break_ctl
2026/09/15 17:05 upstream 587858367581 81a27d1a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root general protection fault in keyspan_break_ctl
2026/09/15 17:03 upstream 587858367581 81a27d1a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root general protection fault in keyspan_break_ctl
2026/09/15 17:03 upstream 587858367581 81a27d1a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root general protection fault in keyspan_break_ctl
2026/09/15 17:01 upstream 587858367581 81a27d1a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root general protection fault in keyspan_break_ctl
2026/09/15 16:24 upstream 587858367581 81a27d1a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root general protection fault in keyspan_break_ctl
2026/10/03 15:56 upstream e767a4ea70a3 57bbd979 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in keyspan_break_ctl
2026/09/27 13:19 upstream fd179f8a05be a3c7249d .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in keyspan_break_ctl
2026/09/25 22:14 upstream 165768bb7026 f281d9d2 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in keyspan_break_ctl
2026/09/25 17:37 upstream 165768bb7026 f281d9d2 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in keyspan_break_ctl
2026/09/25 12:46 upstream 165768bb7026 f281d9d2 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in keyspan_break_ctl
2026/09/24 14:31 upstream 62f4c998b297 3c3cdf19 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in keyspan_break_ctl
2026/09/24 14:26 upstream 62f4c998b297 3c3cdf19 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in keyspan_break_ctl
2026/09/20 17:35 upstream 518e5b794c06 853b104b .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in keyspan_break_ctl
2026/09/19 06:18 upstream 40288c9206c1 853b104b .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in keyspan_break_ctl
2026/09/17 07:17 upstream 238650ef6c7c 95928915 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in keyspan_break_ctl
2026/09/17 02:36 upstream 238650ef6c7c 95928915 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in keyspan_break_ctl
2026/09/15 13:33 upstream 587858367581 f41e228a .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in keyspan_break_ctl
2026/09/14 00:11 upstream d681d7ef617e 70a60e12 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in keyspan_break_ctl
2026/09/13 19:53 upstream d681d7ef617e 70a60e12 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in keyspan_break_ctl
2026/09/13 12:37 upstream 2f0c1cf72f46 70a60e12 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in keyspan_break_ctl
2026/09/12 07:38 upstream 827751b699b7 70a60e12 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in keyspan_break_ctl
2026/09/11 09:35 upstream 50d05c7c76c9 1fe56c0a .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in keyspan_break_ctl
2026/09/03 04:26 upstream 940de590b839 6a988719 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root general protection fault in keyspan_break_ctl
2026/08/25 07:34 upstream 818bebeb63dd 614e416a .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in keyspan_break_ctl
2026/08/25 00:56 upstream 818bebeb63dd 614e416a .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream general protection fault in keyspan_break_ctl
2026/09/14 15:18 upstream 50d05c7c76c9 924033e8 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 general protection fault in keyspan_break_ctl
2026/09/15 22:55 linux-next 9d80aa4617b3 81a27d1a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce general protection fault in keyspan_break_ctl
2026/08/25 00:47 linux-next 4b18edbd8e70 23caa175 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce general protection fault in keyspan_break_ctl
* Struck through repros no longer work on HEAD.