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 vkms_vblank_simulate: vblank timer overrun RSP: 0018:ffffc900001075d8 EFLAGS: 00000206 ================================================================== BUG: KASAN: stack-out-of-bounds in __show_regs+0xa6/0x610 arch/x86/kernel/process_64.c:83 Read of size 8 at addr ffffc90000107578 by task syz.3.712/8701 CPU: 0 UID: 0 PID: 8701 Comm: syz.3.712 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:__sanitizer_cov_trace_pc+0x5d/0x70 kernel/kcov.c:225 Code: f8 15 00 00 83 fa 02 75 21 48 8b 91 00 16 00 00 48 8b 32 48 8d 7e 01 8b 89 fc 15 00 00 48 39 cf 73 08 48 89 3a 48 89 44 f2 08 cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 90 90 90 RSP: 0018:ffffc9000c36f2b8 EFLAGS: 00000287 RAX: ffffffff81cc49de RBX: ffffffff950ddfb8 RCX: 0000000000040000 RDX: ffffc9000e034000 RSI: 00000000000325ff RDI: 0000000000032600 RBP: ffffc9000c36f418 R08: ffffffff848f3648 R09: 1ffffd40002a48f0 R10: dffffc0000000000 R11: fffff940002a48f1 R12: ffffc9000c36f360 R13: 0000000000000cc0 R14: dffffc0000000000 R15: 0000000000000cc0 mempool_alloc_noprof+0x9e/0x5a0 mm/mempool.c:385 bio_alloc_bioset+0x26f/0x1130 block/bio.c:554 bio_alloc include/linux/bio.h:374 [inline] do_mpage_readpage+0x17ad/0x1c80 fs/mpage.c:290 mpage_read_folio+0x108/0x1e0 fs/mpage.c:392 filemap_read_folio+0x1a0/0x790 mm/filemap.c:2355 do_read_cache_folio+0x134/0x820 mm/filemap.c:3789 do_read_cache_page+0x30/0x200 mm/filemap.c:3855 read_mapping_page include/linux/pagemap.h:907 [inline] inode_read_data+0x85/0x450 fs/ntfs3/inode.c:1110 ntfs_fill_super+0x3f29/0x4730 fs/ntfs3/super.c:1486 get_tree_bdev+0x3f7/0x570 fs/super.c:1635 vfs_get_tree+0x90/0x2a0 fs/super.c:1800 do_new_mount+0x2be/0xb40 fs/namespace.c:3472 do_mount fs/namespace.c:3812 [inline] __do_sys_mount fs/namespace.c:4020 [inline] __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:3997 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f9f98d78aba Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 7e 1a 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f9f99b53e78 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f9f99b53f00 RCX: 00007f9f98d78aba RDX: 000000002001f180 RSI: 0000000020000000 RDI: 00007f9f99b53ec0 RBP: 000000002001f180 R08: 00007f9f99b53f00 R09: 0000000001214010 R10: 0000000001214010 R11: 0000000000000202 R12: 0000000020000000 R13: 00007f9f99b53ec0 R14: 000000000001f252 R15: 0000000020000380 The buggy address belongs to the virtual mapping at [ffffc90000100000, ffffc90000109000) 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:0x17a9d 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 2573716852, 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: ffffc90000107400: f2 f2 00 00 00 00 00 00 f2 f2 f2 f2 00 00 00 00 ffffc90000107480: 00 f3 f3 f3 f3 f3 f3 f3 00 00 00 00 00 00 00 00 >ffffc90000107500: 00 00 00 00 f1 f1 f1 f1 00 f2 f2 f2 00 f3 f3 f3 ^ ffffc90000107580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffffc90000107600: f1 f1 f1 f1 00 f2 f2 f2 00 f3 f3 f3 00 00 00 00 ================================================================== vkms_vblank_simulate: vblank timer overrun ---------------- 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