KASAN: unknown-crash Read in futex

Kernel	Title	Rank 🛈	Count	Last	Reported	Patched	Status
upstream	general protection fault in futex_wake (2) kernel	2	2	1772d	1776d	0/29	auto-closed as invalid on 2021/10/21 19:26
upstream	KASAN: null-ptr-deref Read in futex_wake kernel	11	1	1390d	1386d	0/29	auto-obsoleted due to no activity on 2022/11/08 08:41
linux-4.19	general protection fault in futex_wake (2)	2	1	1891d	1891d	0/1	auto-closed as invalid on 2021/07/25 11:26

================================================================== BUG: KASAN: unknown-crash in futex_wake+0x382/0x580 kernel/futex/waitwake.c:191 Read of size 8 at addr ffffc900039dfad8 by task syz.1.9500/26050 CPU: 1 UID: 0 PID: 26050 Comm: syz.1.9500 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 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 futex_wake+0x382/0x580 kernel/futex/waitwake.c:191 do_futex+0x395/0x420 kernel/futex/syscalls.c:135 __do_sys_futex kernel/futex/syscalls.c:207 [inline] __se_sys_futex+0x3a8/0x450 kernel/futex/syscalls.c:188 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0x560 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f3eb3b9ce59 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f3eb3f3fba8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 00000000000002d0 RCX: 00007f3eb3b9ce59 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f3eb3e16278 RBP: 00000000000010e9 R08: 0000000000000000 R09: 0000000000000000 R10: 00007f3eb3e15fa0 R11: 0000000000000246 R12: 0000000000000003 R13: 00007f3eb3e1627c R14: 00007f3eb3e16278 R15: 00007f3eb3e16270 </TASK> The buggy address belongs to a vmalloc virtual mapping The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0xa29e7 memcg:ffff888030daa402 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000000000 00000001ffffffff ffff888030daa402 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x1029c2(GFP_NOWAIT|__GFP_HIGHMEM|__GFP_IO|__GFP_FS|__GFP_ZERO|__GFP_HARDWALL), pid 26050, tgid 26050 (syz.1.9500), ts 2021430196564, free_ts 2021372410361 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x22d/0x280 mm/page_alloc.c:1858 prep_new_page mm/page_alloc.c:1866 [inline] get_page_from_freelist+0x24ba/0x2540 mm/page_alloc.c:3946 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5226 alloc_pages_mpol+0x235/0x490 mm/mempolicy.c:2490 alloc_frozen_pages_noprof mm/mempolicy.c:2561 [inline] alloc_pages_noprof+0xac/0x2a0 mm/mempolicy.c:2581 vm_area_alloc_pages mm/vmalloc.c:3653 [inline] __vmalloc_area_node mm/vmalloc.c:3878 [inline] __vmalloc_node_range_noprof+0x7a7/0x1750 mm/vmalloc.c:4064 __vmalloc_node_noprof+0xc2/0x100 mm/vmalloc.c:4124 alloc_thread_stack_node kernel/fork.c:357 [inline] dup_task_struct+0x298/0x840 kernel/fork.c:926 copy_process+0x89b/0x4440 kernel/fork.c:2090 kernel_clone+0x284/0x8f0 kernel/fork.c:2721 __do_sys_clone3 kernel/fork.c:3025 [inline] __se_sys_clone3+0x33c/0x360 kernel/fork.c:3004 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0x560 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 26050 tgid 26050 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1402 [inline] __free_frozen_pages+0xbc7/0xd30 mm/page_alloc.c:2943 __slab_free+0x274/0x2c0 mm/slub.c:5613 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x99/0x100 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4570 [inline] slab_alloc_node mm/slub.c:4899 [inline] kmem_cache_alloc_noprof+0x2bc/0x650 mm/slub.c:4906 vm_area_dup+0x2b/0x680 mm/vma_init.c:123 __split_vma+0x1dc/0xa40 mm/vma.c:516 split_vma mm/vma.c:599 [inline] vma_modify+0x88a/0x1e10 mm/vma.c:1691 vma_modify_flags+0x24b/0x330 mm/vma.c:1719 mprotect_fixup+0x62a/0xb60 mm/mprotect.c:789 do_mprotect_pkey+0x8d5/0xd20 mm/mprotect.c:967 __do_sys_mprotect mm/mprotect.c:988 [inline] __se_sys_mprotect mm/mprotect.c:985 [inline] __x64_sys_mprotect+0x80/0x90 mm/mprotect.c:985 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0x560 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffffc900039df980: 67 c8 a7 42 00 00 00 00 67 d8 a7 42 00 00 00 00 ffffc900039dfa00: 67 e8 a7 42 00 00 00 00 67 f8 a7 42 00 00 00 00 >ffffc900039dfa80: f1 f1 f1 f1 00 00 00 00 67 18 a8 42 00 00 00 00 ^ ffffc900039dfb00: 00 00 00 00 00 f3 f3 f3 f3 f3 f3 f3 f3 f3 f3 f3 ffffc900039dfb80: 67 48 a8 42 00 00 00 00 67 58 a8 42 00 00 00 00 ==================================================================

Crashes (1):
Time	Kernel	Commit	Syzkaller	Config	Log	Report	Syz repro	C repro	VM info	Assets (help?)	Manager	Title
2026/05/25 22:06	upstream	e7ae89a0c97c	c69befb3	.config	console log	report			info	[disk image] [vmlinux] [kernel image]	ci-upstream-kasan-gce	KASAN: unknown-crash Read in futex_wake

Crashes (1):

Assets (help?)