syzbot


KMSAN: kernel-infoleak in irqentry_exit

Status: fixed on 2026/07/15 08:27
Subsystems: kernel
Labels: prio:high
[Documentation on labels]
Reported-by: syzbot+185a631927096f9da2fc@syzkaller.appspotmail.com
Fix commit: 6d99479799c6 rseq: Fix using an uninitialized stack variable in rseq_exit_user_update()
First crash: 56d, last: 7d03h
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision Error
4fe5b83a-a4b7-4c51-a162-f562d209edae assessment-security DenialOfService: ✅ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ✅ UserNamespace: ✅ VMGuestTrigger: ❌ VMHostTrigger: ❌ KMSAN: kernel-infoleak in irqentry_exit 2026/05/29 20:06 2026/05/29 20:06 2026/05/29 20:41 6b4a844333e83556da95d61d7f207e7ef5cd4bc6

			
		
Discussions (2)
Title Replies (including bot) Last reply
[PATCH] rseq: fix using an uninitialized stack variable in rseq_exit_user_update 12 (12) 2026/06/25 09:18
[syzbot] [kernel?] KMSAN: kernel-infoleak in irqentry_exit 0 (1) 2026/05/31 00:27
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KMSAN: kernel-infoleak in irqentry_exit (2) kernel prio:high 9 11110 1d23h 3d02h 29/29 fixed on 2026/07/20 12:16

Sample crash report:
=====================================================
BUG: KMSAN: kernel-infoleak in rseq_set_ids_get_csaddr include/linux/rseq_entry.h:502 [inline]
BUG: KMSAN: kernel-infoleak in rseq_update_usr include/linux/rseq_entry.h:536 [inline]
BUG: KMSAN: kernel-infoleak in rseq_exit_user_update include/linux/rseq_entry.h:645 [inline]
BUG: KMSAN: kernel-infoleak in __rseq_exit_to_user_mode_restart include/linux/rseq_entry.h:674 [inline]
BUG: KMSAN: kernel-infoleak in rseq_exit_to_user_mode_restart include/linux/rseq_entry.h:703 [inline]
BUG: KMSAN: kernel-infoleak in exit_to_user_mode_loop kernel/entry/common.c:103 [inline]
BUG: KMSAN: kernel-infoleak in __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
BUG: KMSAN: kernel-infoleak in irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:244 [inline]
BUG: KMSAN: kernel-infoleak in irqentry_exit_to_user_mode include/linux/irq-entry-common.h:315 [inline]
BUG: KMSAN: kernel-infoleak in irqentry_exit+0x4a6/0xa40 kernel/entry/common.c:165
 rseq_set_ids_get_csaddr include/linux/rseq_entry.h:502 [inline]
 rseq_update_usr include/linux/rseq_entry.h:536 [inline]
 rseq_exit_user_update include/linux/rseq_entry.h:645 [inline]
 __rseq_exit_to_user_mode_restart include/linux/rseq_entry.h:674 [inline]
 rseq_exit_to_user_mode_restart include/linux/rseq_entry.h:703 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:103 [inline]
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:244 [inline]
 irqentry_exit_to_user_mode include/linux/irq-entry-common.h:315 [inline]
 irqentry_exit+0x4a6/0xa40 kernel/entry/common.c:165
 exc_page_fault+0x7e/0xb0 arch/x86/mm/fault.c:1539
 asm_exc_page_fault+0x2b/0x30 arch/x86/include/asm/idtentry.h:595

Local variable st.i.i created at:
 __do_sys_statfs fs/statfs.c:193 [inline]
 __se_sys_statfs fs/statfs.c:191 [inline]
 __x64_sys_statfs+0x73/0x200 fs/statfs.c:191
 x64_sys_call+0x334c/0x3ea0 arch/x86/include/generated/asm/syscalls_64.h:138

Bytes 0-3 of 4 are uninitialized
Memory access of size 4 starts at ffff888118b3fe78
Data copied to user address 00007fb8e058dac0

CPU: 1 UID: 0 PID: 5246 Comm: rm Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/25/2026
=====================================================

Crashes (61732):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/07/15 08:06 upstream 4a50a141f05a 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 07:56 upstream 4a50a141f05a 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 07:20 upstream 4a50a141f05a 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 07:08 upstream 4a50a141f05a 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 06:40 upstream 4a50a141f05a 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 06:27 upstream 4a50a141f05a 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 06:14 upstream 4a50a141f05a 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 05:59 upstream 4a50a141f05a 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 05:46 upstream 4a50a141f05a 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 05:33 upstream 4a50a141f05a 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 05:20 upstream 4a50a141f05a 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 05:08 upstream 4a50a141f05a 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 04:52 upstream 4a50a141f05a 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 04:28 upstream 4a50a141f05a 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 04:06 upstream 4a50a141f05a 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 03:45 upstream 4a50a141f05a 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 03:32 upstream 4a50a141f05a 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 03:22 upstream 4a50a141f05a 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 03:09 upstream 4a50a141f05a 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 02:57 upstream 4a50a141f05a 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 02:46 upstream 4a50a141f05a 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 02:20 upstream 4a50a141f05a 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 02:03 upstream 4a50a141f05a 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 01:52 upstream 4a50a141f05a 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 01:14 upstream 4a50a141f05a 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 01:00 upstream 4a50a141f05a 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 00:45 upstream 4a50a141f05a 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 00:30 upstream 4a50a141f05a 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 00:19 upstream 4a50a141f05a 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/14 23:51 upstream 4a50a141f05a 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: kernel-infoleak in irqentry_exit
2026/05/30 23:53 upstream 670b77dfebe7 6b4a8443 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: kernel-infoleak in irqentry_exit
2026/05/29 19:44 upstream 8fde5d1d47f6 6b4a8443 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 08:20 upstream a13c140cc289 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 07:42 upstream a13c140cc289 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 07:30 upstream a13c140cc289 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 06:55 upstream a13c140cc289 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 04:40 upstream a13c140cc289 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 04:19 upstream a13c140cc289 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 03:54 upstream a13c140cc289 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 02:35 upstream a13c140cc289 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 01:39 upstream a13c140cc289 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 01:26 upstream a13c140cc289 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 00:19 upstream a13c140cc289 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/15 00:04 upstream a13c140cc289 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: kernel-infoleak in irqentry_exit
2026/07/14 23:39 upstream a13c140cc289 2130f682 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: kernel-infoleak in irqentry_exit
2026/05/27 00:22 upstream d60ec36cab33 2b01f00e .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: kernel-infoleak in irqentry_exit
* Struck through repros no longer work on HEAD.