syzbot


KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt

Status: upstream: reported on 2026/04/19 15:01
Subsystems: kernel
[Documentation on labels]
Reported-by: syzbot+23d7fcd204e3837866ff@syzkaller.appspotmail.com
First crash: 7d20h, last: 42m
Discussions (2)
Title Replies (including bot) Last reply
[PATCH net] netdevsim: Initialize all fields of ip header when building dummy sk_buff 5 (5) 2026/04/21 11:44
[syzbot] [kernel?] KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt 0 (1) 2026/04/19 15:01

Sample crash report:
wlan1: Created IBSS using preconfigured BSSID 50:50:50:50:50:50
wlan1: Creating new IBSS network, BSSID 50:50:50:50:50:50
=====================================================
BUG: KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt+0xb0/0xc0 include/linux/irq-entry-common.h:472
 irqentry_exit_to_kernel_mode_preempt+0xb0/0xc0 include/linux/irq-entry-common.h:472
 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:547 [inline]
 irqentry_exit+0x7b/0x760 kernel/entry/common.c:164
 sysvec_apic_timer_interrupt+0x52/0x90 arch/x86/kernel/apic/apic.c:1061
 asm_sysvec_apic_timer_interrupt+0x1f/0x30 arch/x86/include/asm/idtentry.h:697
 do_csum lib/checksum.c:72 [inline]
 ip_fast_csum+0x2df/0x3f0 lib/checksum.c:99
 nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:842 [inline]
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:876 [inline]
 nsim_dev_trap_report_work+0x8c0/0x1430 drivers/net/netdevsim/dev.c:922
 process_one_work kernel/workqueue.c:3302 [inline]
 process_scheduled_works+0xb65/0x1e40 kernel/workqueue.c:3385
 worker_thread+0xee4/0x1590 kernel/workqueue.c:3466
 kthread+0x53f/0x600 kernel/kthread.c:436
 ret_from_fork+0x20f/0x8d0 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:4576 [inline]
 slab_alloc_node mm/slub.c:4898 [inline]
 __do_kmalloc_node mm/slub.c:5294 [inline]
 __kmalloc_node_track_caller_noprof+0x4f6/0x1750 mm/slub.c:5403
 kmalloc_reserve net/core/skbuff.c:635 [inline]
 __alloc_skb+0x90d/0x1190 net/core/skbuff.c:713
 alloc_skb include/linux/skbuff.h:1383 [inline]
 nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:819 [inline]
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:876 [inline]
 nsim_dev_trap_report_work+0x3f2/0x1430 drivers/net/netdevsim/dev.c:922
 process_one_work kernel/workqueue.c:3302 [inline]
 process_scheduled_works+0xb65/0x1e40 kernel/workqueue.c:3385
 worker_thread+0xee4/0x1590 kernel/workqueue.c:3466
 kthread+0x53f/0x600 kernel/kthread.c:436
 ret_from_fork+0x20f/0x8d0 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

CPU: 1 UID: 0 PID: 5898 Comm: kworker/u8:10 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Workqueue: events_unbound nsim_dev_trap_report_work
=====================================================

Crashes (28513):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/04/23 10:20 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 10:12 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 10:00 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 09:53 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 09:33 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 09:26 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 09:20 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 09:13 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 09:00 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 08:54 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 08:40 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 08:21 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 08:14 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 08:00 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 07:53 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 07:37 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 07:31 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 07:16 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 07:09 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 07:00 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 06:53 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 06:48 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 06:41 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 06:21 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 06:13 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 06:07 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 05:55 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 05:48 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 05:42 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 05:35 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/19 14:58 upstream faeab166167f 303e2802 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 10:06 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 09:46 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 09:40 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 09:07 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 08:47 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 08:33 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 08:26 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 08:07 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 07:46 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 07:24 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 06:35 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 06:27 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/23 06:01 upstream 2a4c0c11c019 b10da5ec .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
2026/04/15 14:57 upstream 1f5ffc672165 c441f497 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in irqentry_exit_to_kernel_mode_preempt
* Struck through repros no longer work on HEAD.