asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707 RIP: 0010:synchronize_rcu+0x0/0x360 kernel/rcu/tree.c:4010 Code: e1 07 80 c1 03 38 c1 0f 8c 97 fe ff ff 4c 89 f7 e8 65 38 81 00 e9 8a fe ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 55 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48 RSP: 7620:0000000000000a03 EFLAGS: 1ffff92000156ec0 ================================================================== BUG: KASAN: stack-out-of-bounds in __show_regs+0xa6/0x610 arch/x86/kernel/process_64.c:83 Read of size 8 at addr ffffc90000ab7578 by task syz.4.407/7439 CPU: 0 UID: 0 PID: 7439 Comm: syz.4.407 Not tainted 6.11.0-rc1-next-20240729-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:377 [inline] print_report+0x169/0x550 mm/kasan/report.c:488 kasan_report+0x143/0x180 mm/kasan/report.c:601 __show_regs+0xa6/0x610 arch/x86/kernel/process_64.c:83 show_trace_log_lvl+0x3d4/0x520 arch/x86/kernel/dumpstack.c:301 sched_show_task+0x506/0x6d0 kernel/sched/core.c:7512 report_rtnl_holders+0x327/0x400 net/core/rtnetlink.c:110 call_timer_fn+0x18e/0x650 kernel/time/timer.c:1792 expire_timers kernel/time/timer.c:1843 [inline] __run_timers kernel/time/timer.c:2417 [inline] __run_timer_base+0x66a/0x8e0 kernel/time/timer.c:2428 run_timer_base kernel/time/timer.c:2437 [inline] run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2447 handle_softirqs+0x2c4/0x970 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637 irq_exit_rcu+0x9/0x30 kernel/softirq.c:649 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:finish_task_switch+0x1ea/0x870 kernel/sched/core.c:5113 Code: c9 50 e8 39 b8 0b 00 48 83 c4 08 4c 89 f7 e8 dd 38 00 00 0f 1f 44 00 00 4c 89 f7 e8 e0 b8 5f 0a e8 fb 85 37 00 fb 48 8b 5d c0 <48> 8d bb f8 15 00 00 48 89 f8 48 c1 e8 03 49 be 00 00 00 00 00 fc RSP: 0000:ffffc9000374fca8 EFLAGS: 00000286 RAX: 3e1b8c438cf29800 RBX: ffff888029a01e00 RCX: ffffffff94f2f903 RDX: dffffc0000000000 RSI: ffffffff8c0ad560 RDI: ffffffff8c607c40 RBP: ffffc9000374fcf0 R08: ffffffff9017d76f R09: 1ffffffff202faed R10: dffffc0000000000 R11: fffffbfff202faee R12: 1ffff11017247ef3 R13: dffffc0000000000 R14: ffff8880b923ea00 R15: ffff8880b923f798 context_switch kernel/sched/core.c:5242 [inline] __schedule+0x1808/0x4a60 kernel/sched/core.c:6603 __schedule_loop kernel/sched/core.c:6680 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6695 exit_to_user_mode_loop kernel/entry/common.c:102 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] irqentry_exit_to_user_mode+0xe7/0x280 kernel/entry/common.c:231 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707 RIP: 0033:0x7fa58de4f44b Code: 83 eb 08 49 8b 04 24 48 8b 0b 31 f6 48 89 dd 4c 89 e7 4c 29 e5 48 89 03 48 89 ea 48 c1 fa 03 e8 9b fa ff ff 48 83 fd 08 7f d5 <48> 83 c4 08 5b 5d 41 5c 41 5d c3 66 2e 0f 1f 84 00 00 00 00 00 48 RSP: 002b:00007ffe17ebdc00 EFLAGS: 00000283 RAX: 0000000000000078 RBX: 00007fa58d6655c0 RCX: ffffffff81423d45 RDX: 0000000000000012 RSI: 00007fa58d665638 RDI: 00007fa58d6655c0 RBP: 00007fa58d665550 R08: 00007fa58d6655c0 R09: 00007fa58e0f2000 R10: 0000000081cd36d0 R11: 000000000000000d R12: 00007fa58d6655c0 R13: 0000000000000012 R14: 00007fa58d601008 R15: ffffffffffffffff The buggy address belongs to the virtual mapping at [ffffc90000ab0000, ffffc90000ab9000) created by: copy_process+0x5d1/0x3d90 kernel/fork.c:2206 The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x186cb flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x2dc2(GFP_KERNEL|__GFP_HIGHMEM|__GFP_NOWARN|__GFP_ZERO), pid 2, tgid 2 (kthreadd), ts 2652945322, free_ts 0 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1493 prep_new_page mm/page_alloc.c:1501 [inline] get_page_from_freelist+0x2e4c/0x2f10 mm/page_alloc.c:3442 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4700 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2263 vm_area_alloc_pages mm/vmalloc.c:3584 [inline] __vmalloc_area_node mm/vmalloc.c:3660 [inline] __vmalloc_node_range_noprof+0x971/0x1460 mm/vmalloc.c:3841 alloc_thread_stack_node kernel/fork.c:314 [inline] dup_task_struct+0x444/0x8c0 kernel/fork.c:1115 copy_process+0x5d1/0x3d90 kernel/fork.c:2206 kernel_clone+0x226/0x8f0 kernel/fork.c:2788 kernel_thread+0x1bc/0x240 kernel/fork.c:2850 create_kthread kernel/kthread.c:412 [inline] kthreadd+0x60d/0x810 kernel/kthread.c:765 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:144 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 page_owner free stack trace missing Memory state around the buggy address: ffffc90000ab7400: f2 f2 00 00 00 00 00 00 f2 f2 f2 f2 00 00 00 00 ffffc90000ab7480: 00 f3 f3 f3 f3 f3 f3 f3 00 00 00 00 00 00 00 00 >ffffc90000ab7500: 00 00 00 00 f1 f1 f1 f1 00 f2 f2 f2 00 f3 f3 f3 ^ ffffc90000ab7580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffffc90000ab7600: f1 f1 f1 f1 00 f2 f2 f2 00 f3 f3 f3 00 00 00 00 ================================================================== ---------------- Code disassembly (best guess): 0: e1 07 loope 0x9 2: 80 c1 03 add $0x3,%cl 5: 38 c1 cmp %al,%cl 7: 0f 8c 97 fe ff ff jl 0xfffffea4 d: 4c 89 f7 mov %r14,%rdi 10: e8 65 38 81 00 call 0x81387a 15: e9 8a fe ff ff jmp 0xfffffea4 1a: 90 nop 1b: 90 nop 1c: 90 nop 1d: 90 nop 1e: 90 nop 1f: 90 nop 20: 90 nop 21: 90 nop 22: 90 nop 23: 90 nop 24: 90 nop 25: 90 nop 26: 90 nop 27: 90 nop 28: 90 nop 29: 90 nop * 2a: f3 0f 1e fa endbr64 <-- trapping instruction 2e: 55 push %rbp 2f: 48 89 e5 mov %rsp,%rbp 32: 41 57 push %r15 34: 41 56 push %r14 36: 41 55 push %r13 38: 41 54 push %r12 3a: 53 push %rbx 3b: 48 83 e4 e0 and $0xffffffffffffffe0,%rsp 3f: 48 rex.W