KCSAN: data-race in __anon_vma_prepare / do_wp

ID	Workflow	Result	Correct	Bug	Created	Started	Finished	Revision	Error
327fb49f-b9ac-4cb6-8335-958fba032aaa	assessment-security	DenialOfService: ❌ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ✅ UserNamespace: ✅ VMGuestTrigger: ❌ VMHostTrigger: ❌	❓	KCSAN: data-race in __anon_vma_prepare / do_wp_page (3)	2026/05/30 10:01	2026/05/30 10:01	2026/05/30 10:41	6b4a844333e83556da95d61d7f207e7ef5cd4bc6
b78a986f-c960-42fc-acb5-de06b4aabaa2	assessment-security		💥	KCSAN: data-race in __anon_vma_prepare / do_wp_page (3)	2026/05/14 09:35	2026/05/14 09:35	2026/05/14 09:36	6ccb967e465e832a7bfd7a116ad00d52a0923a5d	failed to run ["git" "pull" "origin" "HEAD" "--depth=1" "--allow-unrelated-histories"]: exit status 128 From /app/workdir/repo/linux * branch HEAD -> FETCH_HEAD Updating files: ... truncated to first 200 bytes; open job for full error
8c1472fb-26b1-466a-9343-43d28cc2562d	assessment-kcsan	Benign: ✅	❓	KCSAN: data-race in __anon_vma_prepare / do_wp_page (3)	2026/05/09 07:21	2026/05/09 07:21	2026/05/09 07:24	29233ece713919081e9069c2a18be92526041f39

Kernel	Title	Rank 🛈	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in __anon_vma_prepare / do_wp_page mm	6				1	999d	999d	0/29	auto-obsoleted due to no activity on 2023/11/02 18:12
upstream	KCSAN: data-race in __anon_vma_prepare / do_wp_page (2) mm	6				1	952d	926d	0/29	auto-obsoleted due to no activity on 2023/12/25 00:10

Kernel

Title

Rank 🛈

upstream

KCSAN: data-race in __anon_vma_prepare / do_wp_page mm

999d

0/29

auto-obsoleted due to no activity on 2023/11/02 18:12

upstream

KCSAN: data-race in __anon_vma_prepare / do_wp_page (2) mm

952d

926d

0/29

auto-obsoleted due to no activity on 2023/12/25 00:10

================================================================== BUG: KCSAN: data-race in __anon_vma_prepare / do_wp_page write to 0xffff888133dbf040 of 8 bytes by task 14997 on cpu 0: __anon_vma_prepare+0x172/0x2f0 mm/rmap.c:212 __vmf_anon_prepare mm/memory.c:3813 [inline] vmf_anon_prepare mm/internal.h:503 [inline] do_anonymous_page mm/memory.c:5372 [inline] do_pte_missing mm/memory.c:4548 [inline] handle_pte_fault mm/memory.c:6411 [inline] __handle_mm_fault mm/memory.c:6549 [inline] handle_mm_fault+0x24ae/0x2e70 mm/memory.c:6718 faultin_page mm/gup.c:1126 [inline] __get_user_pages+0x1290/0x1f10 mm/gup.c:1428 populate_vma_page_range mm/gup.c:1860 [inline] __mm_populate+0x242/0x390 mm/gup.c:1963 mm_populate include/linux/mm.h:4137 [inline] vm_mmap_pgoff+0x23b/0x2d0 mm/util.c:586 ksys_mmap_pgoff+0xc1/0x310 mm/mmap.c:606 x64_sys_call+0x14df/0x3020 arch/x86/include/generated/asm/syscalls_64.h:10 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x12c/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f read to 0xffff888133dbf040 of 8 bytes by task 14993 on cpu 1: __vmf_anon_prepare mm/memory.c:3807 [inline] vmf_anon_prepare mm/internal.h:503 [inline] wp_page_copy mm/memory.c:3854 [inline] do_wp_page+0x65c/0x2040 mm/memory.c:4320 handle_pte_fault mm/memory.c:6427 [inline] __handle_mm_fault mm/memory.c:6549 [inline] handle_mm_fault+0x8b9/0x2e70 mm/memory.c:6718 do_user_addr_fault+0x3fd/0x1050 arch/x86/mm/fault.c:1385 handle_page_fault arch/x86/mm/fault.c:1474 [inline] exc_page_fault+0x62/0xa0 arch/x86/mm/fault.c:1527 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618 __put_user_nocheck_4+0x3/0x10 arch/x86/lib/putuser.S:97 ____sys_recvmsg+0x1a1/0x280 net/socket.c:2931 ___sys_recvmsg+0x11f/0x3b0 net/socket.c:2960 do_recvmmsg+0x1ef/0x560 net/socket.c:3055 __sys_recvmmsg net/socket.c:3129 [inline] __do_sys_recvmmsg net/socket.c:3152 [inline] __se_sys_recvmmsg net/socket.c:3145 [inline] __x64_sys_recvmmsg+0xe5/0x170 net/socket.c:3145 x64_sys_call+0x80f/0x3020 arch/x86/include/generated/asm/syscalls_64.h:300 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x12c/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f value changed: 0x0000000000000000 -> 0xffff888119e6fde0 Reported by Kernel Concurrency Sanitizer on: CPU: 1 UID: 0 PID: 14993 Comm: syz.4.3335 Tainted: G W syzkaller #0 PREEMPT(full) Tainted: [W]=WARN Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 ==================================================================

Crashes (1):
Time	Kernel	Commit	Syzkaller	Config	Log	Report	Syz repro	C repro	VM info	Assets (help?)	Manager	Title
2026/05/09 00:04	upstream	917719c412c4	b2988c17	.config	console log	report			info	[disk image] [vmlinux] [kernel image]	ci2-upstream-kcsan-gce	KCSAN: data-race in __anon_vma_prepare / do_wp_page

Crashes (1):

Assets (help?)