WARNING in firmware_fallback_sysfs (2)

Status: upstream: reported on 2024/08/09 15:45
Subsystems: kernel
Labels: prio:low
[Documentation on labels]
Reported-by: syzbot+8f06445357a052a92657@syzkaller.appspotmail.com
First crash: 738d, last: 13h08m
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision
268cddb5 assessment-security DenialOfService: ❌ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ✅ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ WARNING in firmware_fallback_sysfs (2) 2026/05/26 07:21 2026/05/26 07:21 2026/05/26 08:21 c69befb3
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [kernel?] WARNING in firmware_fallback_sysfs (2) 0 (1) 2024/08/09 15:45
Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in firmware_fallback_sysfs usb fs -1 syz, C error error 3432 851d 1989d 0/29 auto-obsoleted due to no activity on 2024/06/24 11:12
linux-5.15 WARNING in firmware_fallback_sysfs missing-backport origin:upstream -1 syz, C error 295 9d10h 1236d 0/3 upstream: reported C repro on 2023/03/26 17:15
linux-6.1 WARNING in firmware_fallback_sysfs (2) -1 13 9d10h 9d14h 0/3 upstream: reported on 2026/08/04 21:17
linux-6.6 WARNING in firmware_fallback_sysfs origin:lts-only -1 syz, C inconclusive 580 9d09h 423d 0/2 upstream: reported C repro on 2025/06/17 10:18
linux-6.1 WARNING in firmware_fallback_sysfs origin:upstream missing-backport -1 syz, C error 256 21d 1236d 3/3 fixed on 2026/07/24 15:33

Sample crash report:
usb 2-1: Direct firmware load for v4l-pvrusb2-29xxx-01.fw failed with error -2
usb 2-1: Falling back to sysfs fallback for: v4l-pvrusb2-29xxx-01.fw
------------[ cut here ]------------
ret
WARNING: drivers/base/firmware_loader/fallback.c:148 at fw_load_from_user_helper drivers/base/firmware_loader/fallback.c:148 [inline], CPU#1: pvrusb2-context/2357
WARNING: drivers/base/firmware_loader/fallback.c:148 at firmware_fallback_sysfs+0x755/0xa40 drivers/base/firmware_loader/fallback.c:238, CPU#1: pvrusb2-context/2357
Modules linked in:
CPU: 1 UID: 0 PID: 2357 Comm: pvrusb2-context Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:fw_load_from_user_helper drivers/base/firmware_loader/fallback.c:148 [inline]
RIP: 0010:firmware_fallback_sysfs+0x755/0xa40 drivers/base/firmware_loader/fallback.c:238
Code: 9b fb e9 48 fc ff ff e8 69 e1 9b fb c6 05 a8 ad 15 0a 01 48 c7 c7 40 ea 75 8c e8 66 99 fc fa e9 70 fc ff ff e8 4c e1 9b fb 90 <0f> 0b 90 4c 89 f7 48 c7 c6 40 eb 75 8c 4c 89 e2 e8 56 12 01 fb e9
RSP: 0018:ffffc90006def680 EFLAGS: 00010293
RAX: ffffffff862b2014 RBX: dffffc0000000000 RCX: ffff88802c2f3e00
RDX: 0000000000000000 RSI: 00000000fffffff5 RDI: 0000000000000000
RBP: 0000000000000001 R08: ffffffff90574b37 R09: 1ffffffff20ae966
R10: dffffc0000000000 R11: fffffbfff20ae967 R12: ffffffff8cd0cca0
R13: 0000000000001770 R14: ffff8880543e60b0 R15: 00000000fffffff5
FS:  0000000000000000(0000) GS:ffff888125052000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000ffc000 CR3: 000000000e946000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 _request_firmware+0x1049/0x1780 drivers/base/firmware_loader/main.c:898
 request_firmware+0x36/0x50 drivers/base/firmware_loader/main.c:948
 pvr2_locate_firmware+0xb3/0x500 drivers/media/usb/pvrusb2/pvrusb2-hdw.c:1359
 pvr2_upload_firmware1+0x1bd/0x940 drivers/media/usb/pvrusb2/pvrusb2-hdw.c:1426
 pvr2_hdw_setup_low drivers/media/usb/pvrusb2/pvrusb2-hdw.c:2107 [inline]
 pvr2_hdw_setup drivers/media/usb/pvrusb2/pvrusb2-hdw.c:2261 [inline]
 pvr2_hdw_initialize+0x425/0x3c60 drivers/media/usb/pvrusb2/pvrusb2-hdw.c:2338
 pvr2_context_check drivers/media/usb/pvrusb2/pvrusb2-context.c:111 [inline]
 pvr2_context_thread_func+0x504/0xc10 drivers/media/usb/pvrusb2/pvrusb2-context.c:158
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Crashes (340):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/08/13 23:08 upstream 3aa1dcaa4f6f a9ede23c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/08/13 18:00 upstream 3d6d817622b0 a9ede23c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/08/13 11:01 upstream 3d6d817622b0 67796a05 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/08/12 23:36 upstream 3d6d817622b0 7ae4acc7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/08/11 17:31 upstream f5bbbfec59b4 37a258dd .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/08/10 19:02 upstream db2ddb871435 039457bd .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/08/09 18:04 upstream 06cf61899d64 5d63f80b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/08/08 04:24 upstream 9a143525f62b e4ef95d6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/08/07 11:55 upstream f9a2394a2348 e4ef95d6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/08/07 03:30 upstream 0d8395707651 c38879ea .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/08/04 22:58 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in firmware_fallback_sysfs
2026/08/04 18:47 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in firmware_fallback_sysfs
2026/08/04 17:16 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in firmware_fallback_sysfs
2026/08/04 16:03 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in firmware_fallback_sysfs
2026/08/04 15:03 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in firmware_fallback_sysfs
2026/08/04 14:24 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in firmware_fallback_sysfs
2026/08/03 02:53 upstream bd1dde877520 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/08/02 11:24 upstream 2d2338c93da7 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/07/28 13:41 upstream 62cc90241548 45ae1df4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/07/28 12:01 upstream 62cc90241548 45ae1df4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/07/28 11:52 upstream 62cc90241548 45ae1df4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/07/23 17:25 upstream 4539944e5151 71a13572 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/07/22 16:46 upstream 248951ddc14d b561ce9c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/07/22 08:21 upstream 248951ddc14d b561ce9c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/07/14 08:24 upstream 0f26556c5eee 2130f682 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/07/13 21:35 upstream 0f26556c5eee a870962e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/07/09 17:52 upstream 0e35b9b6ec0f b9f1ceaa .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/07/06 08:19 upstream f105f3631d51 fcece630 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/07/05 20:31 upstream f105f3631d51 fcece630 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/07/02 16:04 upstream 4a50a141f05a 2b70b115 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/06/28 07:20 upstream 780d569e6c4b fb92f11c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in firmware_fallback_sysfs
2026/06/26 09:40 upstream 4edcdefd4083 7ff32d8b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in firmware_fallback_sysfs
2026/06/26 03:42 upstream 962528fef902 432fd51a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/06/25 16:38 upstream ab9de95c9cf9 432fd51a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/06/24 19:26 upstream 840ef6c78e6a c1da772e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/06/24 01:53 upstream f31c00c377cc 042555ff .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/06/23 09:30 upstream 502d801f0ab0 4b1d8f01 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/06/21 17:15 upstream 390d73adf896 43bfcdb0 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root WARNING in firmware_fallback_sysfs
2026/06/20 16:18 upstream 1a3746ccbb0a 43bfcdb0 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/06/19 14:32 upstream 8c13415c8a43 d7ffd47b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/06/18 14:17 upstream e771677c937d a776b0d0 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/06/17 05:30 upstream 6b5a2b7d9bc1 62cc6db3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/06/17 01:32 upstream 6b5a2b7d9bc1 0e4b3e40 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/06/15 21:16 upstream 0e0611827f33 50bb0618 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/06/11 16:17 upstream 9716c086c8e8 d93a6ab6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/06/03 18:21 upstream ba3e43a9e601 234057e5 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/06/03 08:33 upstream ba3e43a9e601 3c0d2131 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/06/02 21:07 upstream 6f3ed7fec72f 62fe1528 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/06/02 06:31 upstream e43ffb69e043 1095583b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/05/30 17:24 upstream f5e5d3509bff 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/05/30 16:02 upstream f5e5d3509bff 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/05/23 00:31 upstream cca95436be15 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2026/03/09 05:45 upstream 014441d1e4b2 5cb44a80 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce WARNING in firmware_fallback_sysfs
2025/07/05 12:32 upstream a79a588fc176 4f67c4ae .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root WARNING in firmware_fallback_sysfs
2024/08/05 15:38 upstream de9c2c66ad8e e35c337f .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-root WARNING in firmware_fallback_sysfs
2026/08/10 08:18 upstream b9b3e33b70b7 5d63f80b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 WARNING in firmware_fallback_sysfs
2026/07/18 04:31 upstream af5e34a41cd6 72524a66 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 WARNING in firmware_fallback_sysfs
2026/08/04 18:19 upstream 848acc8ffe1b 3c5eaa21 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream WARNING in firmware_fallback_sysfs
2026/08/04 13:21 upstream 848acc8ffe1b 3c5eaa21 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 WARNING in firmware_fallback_sysfs
2026/07/03 17:13 bpf d2c9a99135da 58bf2096 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-kasan-gce WARNING in firmware_fallback_sysfs
2026/05/04 17:00 net-next 98878ed91b68 85f1bcf2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce WARNING in firmware_fallback_sysfs
2026/04/29 10:11 bpf-next 9f5b3ffc3f1d 95008c03 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-bpf-next-kasan-gce WARNING in firmware_fallback_sysfs
2026/08/04 20:51 linux-next cc2b5f627e8c d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in firmware_fallback_sysfs
2026/07/14 10:05 linux-next 49362394dad7 2130f682 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in firmware_fallback_sysfs
2026/06/20 18:48 linux-next ec039126b7fa 43bfcdb0 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce WARNING in firmware_fallback_sysfs
2026/03/03 15:42 linux-next c025f6cf4209 4180d919 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING in firmware_fallback_sysfs
* Struck through repros no longer work on HEAD.