syzbot


WARNING in comedi_unlocked_ioctl

Status: upstream: reported C repro on 2025/07/04 08:17
Subsystems: comedi mm
[Documentation on labels]
Reported-by: syzbot+d6995b62e5ac7d79557a@syzkaller.appspotmail.com
Fix commit: 08ae4b20f5e8 comedi: Fail COMEDI_INSNLIST ioctl if n_insns is too large
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-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-kmsan-gce-386-root ci-upstream-kmsan-gce-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-qemu2-riscv64 ci-upstream-bpf-kasan-gce ci-upstream-bpf-next-kasan-gce]
First crash: 21d, last: 5d00h
Discussions (2)
Title Replies (including bot) Last reply
[PATCH] comedi: Fail COMEDI_INSNLIST ioctl if n_insns is too large 1 (1) 2025/07/04 12:04
[syzbot] [kernel?] WARNING in comedi_unlocked_ioctl 0 (1) 2025/07/04 08:17
Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.6 WARNING in comedi_unlocked_ioctl origin:upstream -1 C 9 1d20h 14d 0/2 upstream: reported C repro on 2025/07/11 04:26
linux-5.15 WARNING in comedi_unlocked_ioctl origin:upstream -1 C 16 5h57m 15d 0/3 upstream: reported C repro on 2025/07/10 11:52
linux-6.1 WARNING in comedi_unlocked_ioctl origin:upstream -1 C 13 4d06h 14d 0/3 upstream: reported C repro on 2025/07/11 04:55

Sample crash report:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 5545 at mm/page_alloc.c:4935 __alloc_frozen_pages_noprof+0x2c8/0x370 mm/page_alloc.c:4935
Modules linked in:
CPU: 0 UID: 0 PID: 5545 Comm: syz.0.16 Not tainted 6.16.0-rc4-syzkaller-00123-g4c06e63b9203 #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:__alloc_frozen_pages_noprof+0x2c8/0x370 mm/page_alloc.c:4935
Code: 74 10 4c 89 e7 89 54 24 0c e8 24 14 0d 00 8b 54 24 0c 49 83 3c 24 00 0f 85 a5 fe ff ff e9 a6 fe ff ff c6 05 72 f5 74 0d 01 90 <0f> 0b 90 e9 18 ff ff ff a9 00 00 08 00 48 8b 4c 24 10 4c 8d 44 24
RSP: 0018:ffffc90002c0f960 EFLAGS: 00010246
RAX: ffffc90002c0f900 RBX: 0000000000000019 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffc90002c0f9c8
RBP: ffffc90002c0fa50 R08: ffffc90002c0f9c7 R09: 0000000000000000
R10: ffffc90002c0f9a0 R11: fffff52000581f39 R12: 0000000000000000
R13: 1ffff92000581f30 R14: 0000000000040dc0 R15: dffffc0000000000
FS:  00005555918fc500(0000) GS:ffff88808d21c000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000008 CR3: 0000000012196000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 __alloc_pages_noprof+0xa/0x30 mm/page_alloc.c:4993
 __alloc_pages_node_noprof include/linux/gfp.h:284 [inline]
 alloc_pages_node_noprof include/linux/gfp.h:311 [inline]
 ___kmalloc_large_node+0x85/0x210 mm/slub.c:4272
 __kmalloc_large_node_noprof+0x18/0x90 mm/slub.c:4300
 __do_kmalloc_node mm/slub.c:4316 [inline]
 __kmalloc_noprof+0x36f/0x4f0 mm/slub.c:4340
 kmalloc_noprof include/linux/slab.h:909 [inline]
 kmalloc_array_noprof include/linux/slab.h:948 [inline]
 comedi_unlocked_ioctl+0x9ee/0xf40 drivers/comedi/comedi_fops.c:2242
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:907 [inline]
 __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6cd0d8e929
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd9e4829b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f6cd0fb5fa0 RCX: 00007f6cd0d8e929
RDX: 0000200000000000 RSI: 000000008010640b RDI: 0000000000000003
RBP: 00007f6cd0e10b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6cd0fb5fa0 R14: 00007f6cd0fb5fa0 R15: 0000000000000003
 </TASK>

Crashes (262):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/07/04 05:27 upstream 4c06e63b9203 76ad128c .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in comedi_unlocked_ioctl
2025/07/04 04:24 upstream 4c06e63b9203 76ad128c .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in comedi_unlocked_ioctl
2025/07/04 03:28 upstream 4c06e63b9203 76ad128c .config console log report syz / log C [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in comedi_unlocked_ioctl
2025/07/13 09:21 linux-next a62b7a37e6fc 3cda49cf .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in comedi_unlocked_ioctl
2025/07/12 20:38 linux-next a62b7a37e6fc 3cda49cf .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in comedi_unlocked_ioctl
2025/07/07 12:25 linux-next 26ffb3d6f02c 4f67c4ae .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in comedi_unlocked_ioctl
2025/07/20 15:04 upstream f4a40a4282f4 7117feec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in comedi_unlocked_ioctl
2025/07/20 03:40 upstream bf61759db409 7117feec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in comedi_unlocked_ioctl
2025/07/19 19:29 upstream 4871b7cb27f4 7117feec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in comedi_unlocked_ioctl
2025/07/18 09:44 upstream 6832a9317eee 0d1223f1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in comedi_unlocked_ioctl
2025/07/18 00:03 upstream e2291551827f 0d1223f1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in comedi_unlocked_ioctl
2025/07/17 16:11 upstream e2291551827f 0d1223f1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in comedi_unlocked_ioctl
2025/07/17 11:42 upstream e2291551827f 44f8051e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in comedi_unlocked_ioctl
2025/07/16 21:21 upstream 155a3c003e55 c118d736 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in comedi_unlocked_ioctl
2025/07/16 18:43 upstream 155a3c003e55 c118d736 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in comedi_unlocked_ioctl
2025/07/16 06:20 upstream 155a3c003e55 03fcfc4b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in comedi_unlocked_ioctl
2025/07/15 21:43 upstream 155a3c003e55 03fcfc4b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in comedi_unlocked_ioctl
2025/07/10 19:38 upstream 8c2e52ebbe88 19d4829f .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in comedi_unlocked_ioctl
2025/07/21 00:16 upstream 990b11a523a8 7117feec .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in comedi_unlocked_ioctl
2025/07/20 23:59 upstream f4a40a4282f4 7117feec .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in comedi_unlocked_ioctl
2025/07/20 18:32 upstream 990b11a523a8 7117feec .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in comedi_unlocked_ioctl
2025/07/20 11:00 upstream f4a40a4282f4 7117feec .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in comedi_unlocked_ioctl
2025/07/20 08:36 upstream bf61759db409 7117feec .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in comedi_unlocked_ioctl
2025/07/20 05:02 upstream bf61759db409 7117feec .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in comedi_unlocked_ioctl
2025/07/19 13:19 upstream 4871b7cb27f4 7117feec .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in comedi_unlocked_ioctl
2025/07/19 13:18 upstream 4871b7cb27f4 7117feec .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in comedi_unlocked_ioctl
2025/07/19 12:00 upstream c7de79e662b8 7117feec .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in comedi_unlocked_ioctl
2025/07/19 08:49 upstream d786aba32000 7117feec .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in comedi_unlocked_ioctl
2025/07/19 07:07 upstream d786aba32000 7117feec .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in comedi_unlocked_ioctl
2025/07/19 01:19 upstream d786aba32000 7117feec .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in comedi_unlocked_ioctl
2025/07/19 00:01 upstream c7de79e662b8 7117feec .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in comedi_unlocked_ioctl
2025/07/18 20:42 upstream 6832a9317eee f550e092 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in comedi_unlocked_ioctl
2025/07/18 19:03 upstream 6832a9317eee 7117feec .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in comedi_unlocked_ioctl
2025/07/18 16:24 upstream 6832a9317eee 7117feec .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in comedi_unlocked_ioctl
2025/07/18 11:44 upstream 6832a9317eee f550e092 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in comedi_unlocked_ioctl
2025/07/18 11:44 upstream 6832a9317eee f550e092 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in comedi_unlocked_ioctl
2025/07/18 07:56 upstream 6832a9317eee 88248e14 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in comedi_unlocked_ioctl
2025/07/18 02:31 upstream 6832a9317eee 88248e14 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in comedi_unlocked_ioctl
2025/07/17 21:09 upstream e2291551827f 0ea0ca3f .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in comedi_unlocked_ioctl
2025/07/17 19:29 upstream e2291551827f 0ea0ca3f .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in comedi_unlocked_ioctl
2025/07/17 16:29 upstream e2291551827f 0ea0ca3f .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in comedi_unlocked_ioctl
2025/07/17 07:19 upstream e2291551827f 44f8051e .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in comedi_unlocked_ioctl
2025/07/17 05:38 upstream e2291551827f 44f8051e .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in comedi_unlocked_ioctl
2025/07/17 01:31 upstream e2291551827f 44f8051e .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in comedi_unlocked_ioctl
2025/07/16 23:35 upstream 155a3c003e55 44f8051e .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in comedi_unlocked_ioctl
2025/07/16 13:38 upstream 155a3c003e55 124ec9cc .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in comedi_unlocked_ioctl
2025/07/16 12:10 upstream 155a3c003e55 124ec9cc .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in comedi_unlocked_ioctl
2025/07/16 00:36 upstream 155a3c003e55 03fcfc4b .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in comedi_unlocked_ioctl
2025/07/15 23:24 upstream 155a3c003e55 03fcfc4b .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in comedi_unlocked_ioctl
2025/07/15 18:19 upstream 155a3c003e55 03fcfc4b .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-snapshot-upstream-root WARNING in comedi_unlocked_ioctl
2025/07/17 10:13 linux-next e8352908bdcd 44f8051e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in comedi_unlocked_ioctl
2025/07/15 19:28 linux-next 0be23810e32e 03fcfc4b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in comedi_unlocked_ioctl
2025/07/15 03:17 linux-next 0be23810e32e 03fcfc4b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in comedi_unlocked_ioctl
2025/07/20 16:38 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci aaef6f251176 7117feec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in comedi_unlocked_ioctl
2025/07/19 04:38 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci aaef6f251176 f550e092 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in comedi_unlocked_ioctl
2025/07/16 03:56 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci ec4801305969 03fcfc4b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in comedi_unlocked_ioctl
* Struck through repros no longer work on HEAD.