syzbot


KASAN: vmalloc-out-of-bounds Read in kcov_remote_start

Status: upstream: reported on 2025/10/05 04:26
Subsystems: bluetooth usb
Labels: prio:normal
[Documentation on labels]
Reported-by: syzbot+8a173e13208949931dc7@syzkaller.appspotmail.com
First crash: 283d, last: 1h27m
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision Error
4a93e1b2-5dbe-4aa4-aa4c-12062719945b assessment-security DenialOfService: ❌ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ KASAN: vmalloc-out-of-bounds Read in kcov_remote_start 2026/05/23 06:13 2026/05/23 06:13 2026/05/23 07:07 c69befb30ac10e158cc9d1557b508ee3f0eca1de

			
		
Discussions (10)
Title Replies (including bot) Last reply
[PATCH v6] kcov: fix data corruption and race conditions on PREEMPT_RT by moving saved remote state to task_struct 3 (3) 2026/07/10 14:24
Re: [PATCH v5] kcov: fix data corruption and race conditions on PREEMPT_RT by moving saved remote state to task_struct 2 (2) 2026/07/10 10:43
[syzbot] Monthly bluetooth report (Jul 2026) 0 (1) 2026/07/04 04:32
[PATCH] kcov: fix potential kcov_mode corruption under CONFIG_PREEMPT_RT 5 (5) 2026/05/21 08:38
[syzbot] Monthly usb report (May 2026) 0 (1) 2026/05/02 12:32
[syzbot] Monthly bluetooth report (May 2026) 0 (1) 2026/05/02 12:32
[syzbot] Monthly bluetooth report (Apr 2026) 0 (1) 2026/04/01 07:42
[syzbot] Monthly bluetooth report (Jan 2026) 0 (1) 2026/01/28 22:38
[syzbot] Monthly bluetooth report (Dec 2025) 0 (1) 2025/12/29 08:12
[syzbot] [usb?] KASAN: vmalloc-out-of-bounds Read in kcov_remote_start 0 (1) 2025/10/05 04:26

Sample crash report:
==================================================================
BUG: KASAN: vmalloc-out-of-bounds in __list_del_entry_valid_or_report+0xb5/0x190 lib/list_debug.c:65
Read of size 8 at addr ffffc9000eb51008 by task kworker/0:1/16401

CPU: 0 UID: 0 PID: 16401 Comm: kworker/0:1 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Workqueue: usb_hub_wq hub_event
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_address_description+0x55/0x1e0 mm/kasan/report.c:378
 print_report+0x58/0x70 mm/kasan/report.c:482
 kasan_report+0x117/0x150 mm/kasan/report.c:595
 __list_del_entry_valid_or_report+0xb5/0x190 lib/list_debug.c:65
 __list_del_entry_valid include/linux/list.h:132 [inline]
 __list_del_entry include/linux/list.h:246 [inline]
 list_del include/linux/list.h:260 [inline]
 kcov_remote_area_get kernel/kcov.c:143 [inline]
 kcov_remote_start+0x295/0x6f0 kernel/kcov.c:930
 kcov_remote_start_usb include/linux/kcov.h:53 [inline]
 hub_event+0x15d/0x4cf0 drivers/usb/core/hub.c:5889
 process_one_work kernel/workqueue.c:3322 [inline]
 process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405
 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486
 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>

The buggy address belongs to a vmalloc virtual mapping
Memory state around the buggy address:
 ffffc9000eb50f00: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
 ffffc9000eb50f80: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
>ffffc9000eb51000: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
                      ^
 ffffc9000eb51080: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
 ffffc9000eb51100: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
==================================================================

Crashes (3241):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/07/11 14:00 upstream d96fcfe1b7f9 d78ea535 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: vmalloc-out-of-bounds Read in kcov_remote_start
2026/07/10 17:21 upstream a635d6748234 99e64375 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: vmalloc-out-of-bounds Read in kcov_remote_start
2026/07/10 09:34 upstream 2c7c88a412aa 4167ee25 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: vmalloc-out-of-bounds Read in kcov_remote_start
2026/07/10 03:37 upstream 2c7c88a412aa 4167ee25 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: vmalloc-out-of-bounds Read in kcov_remote_start
2026/07/09 21:51 upstream 2c7c88a412aa 4167ee25 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: vmalloc-out-of-bounds Read in kcov_remote_start
2026/07/09 08:56 upstream 0e35b9b6ec0f b9f1ceaa .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: vmalloc-out-of-bounds Read in kcov_remote_start
2026/07/09 02:49 upstream 0e35b9b6ec0f b9f1ceaa .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: vmalloc-out-of-bounds Read in kcov_remote_start
2026/07/09 01:27 upstream 0e35b9b6ec0f b9f1ceaa .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: vmalloc-out-of-bounds Read in kcov_remote_start
2026/07/08 22:38 upstream 0e35b9b6ec0f ab40da58 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: vmalloc-out-of-bounds Read in kcov_remote_start
2026/07/08 17:42 upstream 0e35b9b6ec0f ab40da58 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: vmalloc-out-of-bounds Read in kcov_remote_start
2026/07/07 18:56 upstream 0e35b9b6ec0f 88a4b44c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: vmalloc-out-of-bounds Read in kcov_remote_start
2026/07/07 13:58 upstream 0e35b9b6ec0f 8e71ce95 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: vmalloc-out-of-bounds Read in kcov_remote_start
2026/07/07 13:07 upstream 0e35b9b6ec0f 8e71ce95 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: vmalloc-out-of-bounds Read in kcov_remote_start
2026/07/07 02:20 upstream 8cdeaa50eae8 8e71ce95 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: vmalloc-out-of-bounds Read in kcov_remote_start
2026/07/06 23:28 upstream 8cdeaa50eae8 88b240e4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: vmalloc-out-of-bounds Read in kcov_remote_start
2026/05/22 20:33 upstream 45255ea1ca09 e16cf9f3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: vmalloc-out-of-bounds Read in kcov_remote_start
2026/03/09 04:48 upstream 014441d1e4b2 5cb44a80 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: vmalloc-out-of-bounds Read in kcov_remote_start
2025/10/05 02:43 upstream d104e3d17f7b 49379ee0 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: vmalloc-out-of-bounds Read in kcov_remote_start
2025/10/01 04:17 upstream 50c19e20ed2e 65a0eece .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: vmalloc-out-of-bounds Read in kcov_remote_start
2026/07/08 03:35 linux-next 5c73cd9f0819 88a4b44c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce KASAN: vmalloc-out-of-bounds Read in kcov_remote_start
2026/07/07 22:22 linux-next 5c73cd9f0819 88a4b44c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce KASAN: vmalloc-out-of-bounds Read in kcov_remote_start
2026/07/07 20:25 linux-next 5c73cd9f0819 88a4b44c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root KASAN: vmalloc-out-of-bounds Read in kcov_remote_start
2026/07/06 19:46 linux-next 8e9685d3c41c 88b240e4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce KASAN: vmalloc-out-of-bounds Read in kcov_remote_start
2026/07/06 14:22 linux-next 2b763db0c276 88b240e4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root KASAN: vmalloc-out-of-bounds Read in kcov_remote_start
2026/07/06 09:47 linux-next 2b763db0c276 fcece630 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root KASAN: vmalloc-out-of-bounds Read in kcov_remote_start
2026/07/11 12:44 upstream d96fcfe1b7f9 d78ea535 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root BUG: unable to handle kernel paging request in kcov_remote_start
2026/07/11 09:46 upstream d96fcfe1b7f9 d78ea535 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root BUG: corrupted list in kcov_remote_start
2026/07/11 01:23 upstream a635d6748234 99e64375 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root BUG: unable to handle kernel paging request in kcov_remote_start
2026/07/10 12:59 upstream a635d6748234 4167ee25 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root BUG: unable to handle kernel NULL pointer dereference in kcov_remote_start
2026/07/10 06:34 upstream 2c7c88a412aa 4167ee25 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root BUG: unable to handle kernel NULL pointer dereference in kcov_remote_start
2026/07/10 05:10 upstream 2c7c88a412aa 4167ee25 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root BUG: unable to handle kernel NULL pointer dereference in kcov_remote_start
2026/07/10 02:31 upstream 2c7c88a412aa 4167ee25 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root BUG: unable to handle kernel NULL pointer dereference in kcov_remote_start
2026/07/09 06:18 upstream 0e35b9b6ec0f b9f1ceaa .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root BUG: unable to handle kernel NULL pointer dereference in kcov_remote_start
2026/07/08 19:00 upstream 0e35b9b6ec0f ab40da58 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root BUG: unable to handle kernel NULL pointer dereference in kcov_remote_start
2026/07/08 08:17 upstream 0e35b9b6ec0f 88a4b44c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root BUG: unable to handle kernel NULL pointer dereference in kcov_remote_start
2026/07/07 15:50 upstream 0e35b9b6ec0f 8e71ce95 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root BUG: unable to handle kernel NULL pointer dereference in kcov_remote_start
2026/07/07 06:05 upstream 0e35b9b6ec0f 8e71ce95 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root BUG: unable to handle kernel NULL pointer dereference in kcov_remote_start
2026/07/06 21:36 upstream 8cdeaa50eae8 88b240e4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root BUG: corrupted list in kcov_remote_start
2026/07/06 20:06 upstream 8cdeaa50eae8 88b240e4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root BUG: unable to handle kernel NULL pointer dereference in kcov_remote_start
2026/07/06 17:28 upstream 8cdeaa50eae8 88b240e4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root BUG: unable to handle kernel paging request in kcov_remote_start
2026/07/06 11:21 upstream 8cdeaa50eae8 fcece630 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root BUG: unable to handle kernel NULL pointer dereference in kcov_remote_start
2026/07/08 14:04 linux-next 5c73cd9f0819 ab40da58 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root BUG: unable to handle kernel paging request in kcov_remote_start
2026/07/08 12:33 linux-next 5c73cd9f0819 ab40da58 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root BUG: unable to handle kernel NULL pointer dereference in kcov_remote_start
2026/07/08 11:16 linux-next 5c73cd9f0819 ab40da58 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root BUG: unable to handle kernel NULL pointer dereference in kcov_remote_start
2026/07/08 08:49 linux-next 5c73cd9f0819 88a4b44c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root BUG: unable to handle kernel NULL pointer dereference in kcov_remote_start
2026/07/08 06:44 linux-next 5c73cd9f0819 88a4b44c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root BUG: corrupted list in kcov_remote_start
2026/07/07 10:34 linux-next 8e9685d3c41c 8e71ce95 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce BUG: unable to handle kernel NULL pointer dereference in kcov_remote_start
2026/07/07 08:33 linux-next 8e9685d3c41c 8e71ce95 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce BUG: corrupted list in kcov_remote_start
2026/07/07 07:09 linux-next 8e9685d3c41c 8e71ce95 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce BUG: unable to handle kernel NULL pointer dereference in kcov_remote_start
2026/07/07 04:52 linux-next 8e9685d3c41c 8e71ce95 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root BUG: corrupted list in kcov_remote_start
2026/07/07 00:56 linux-next 8e9685d3c41c 8e71ce95 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-rust-kasan-gce BUG: unable to handle kernel paging request in kcov_remote_start
* Struck through repros no longer work on HEAD.