================================================================== BUG: KASAN: use-after-free in hlist_add_head include/linux/list.h:814 [inline] BUG: KASAN: use-after-free in enqueue_timer+0xb7/0x300 kernel/time/timer.c:541 Write of size 8 at addr ffff8881d5b231c8 by task syz.2.400/1569 CPU: 1 PID: 1569 Comm: syz.2.400 Not tainted 5.4.276-syzkaller-00021-g58de09405d1e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1d8/0x241 lib/dump_stack.c:118 print_address_description+0x8c/0x600 mm/kasan/report.c:384 __kasan_report+0xf3/0x120 mm/kasan/report.c:516 kasan_report+0x30/0x60 mm/kasan/common.c:653 hlist_add_head include/linux/list.h:814 [inline] enqueue_timer+0xb7/0x300 kernel/time/timer.c:541 __internal_add_timer kernel/time/timer.c:554 [inline] internal_add_timer+0x240/0x430 kernel/time/timer.c:604 __mod_timer+0x6f1/0x13e0 kernel/time/timer.c:1065 call_timer_fn+0x36/0x390 kernel/time/timer.c:1448 expire_timers kernel/time/timer.c:1493 [inline] __run_timers+0x879/0xbe0 kernel/time/timer.c:1817 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1830 __do_softirq+0x23b/0x6b7 kernel/softirq.c:292 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0x195/0x1c0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:539 [inline] smp_apic_timer_interrupt+0x11a/0x460 arch/x86/kernel/apic/apic.c:1149 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:834 RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:166 [inline] RIP: 0010:unwind_next_frame+0x2a5/0x1ea0 arch/x86/kernel/unwind_orc.c:438 Code: f8 48 8d 1c 85 60 3d b6 86 48 89 d8 48 c1 e8 03 49 bd 00 00 00 00 00 fc ff df 42 0f b6 04 28 84 c0 0f 85 53 18 00 00 44 8b 33 <44> 89 f8 ff c0 48 8d 1c 85 60 3d b6 86 48 89 d8 48 c1 e8 03 42 0f RSP: 0018:ffff8881dec7eb80 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000000 RBX: ffffffff86b6e4b4 RCX: ffffffff86e99903 RDX: 0000000000038021 RSI: ffff8881dec7eb00 RDI: 0000000000000001 RBP: ffff8881dec7ee70 R08: dffffc0000000000 R09: ffff8881dec7efd0 R10: 0000000000000000 R11: dffffc0000000001 R12: ffffffff8129d56c R13: dffffc0000000000 R14: 00000000000082e4 R15: 00000000000029d5 __unwind_start+0x708/0x890 arch/x86/kernel/unwind_orc.c:691 unwind_start arch/x86/include/asm/unwind.h:60 [inline] arch_stack_walk+0xdd/0x140 arch/x86/kernel/stacktrace.c:24 stack_trace_save+0x118/0x1c0 kernel/stacktrace.c:123 save_stack mm/kasan/common.c:70 [inline] set_track mm/kasan/common.c:78 [inline] __kasan_kmalloc+0x171/0x210 mm/kasan/common.c:529 slab_post_alloc_hook mm/slab.h:584 [inline] slab_alloc_node mm/slub.c:2829 [inline] slab_alloc mm/slub.c:2837 [inline] kmem_cache_alloc+0xd9/0x250 mm/slub.c:2842 skb_clone+0x1c0/0x360 net/core/skbuff.c:1467 ____bpf_clone_redirect net/core/filter.c:2136 [inline] bpf_clone_redirect+0xa2/0x350 net/core/filter.c:2123 bpf_prog_76b644e67229c872+0x513/0x1000 bpf_call_func include/linux/filter.h:627 [inline] bpf_test_run+0x2ae/0x6c0 net/bpf/test_run.c:44 bpf_prog_test_run_skb+0x73c/0xf00 net/bpf/test_run.c:311 bpf_prog_test_run kernel/bpf/syscall.c:2124 [inline] __do_sys_bpf kernel/bpf/syscall.c:2909 [inline] __se_sys_bpf+0x2e37/0xbcb0 kernel/bpf/syscall.c:2849 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x5c/0xc1 RIP: 0033:0x7fb865783b99 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fb864a05048 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007fb865911f60 RCX: 00007fb865783b99 RDX: 0000000000000050 RSI: 0000000020000080 RDI: 000000000000000a RBP: 00007fb8657f2a7a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007fb865911f60 R15: 00007ffe4a2eb7b8 The buggy address belongs to the page: page:ffffea000756c8c0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 flags: 0x8000000000000000() raw: 8000000000000000 ffff8881e91efac0 ffffea000756c888 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as freed page last allocated via order 0, migratetype Unmovable, gfp_mask 0x102cc2(GFP_HIGHUSER|__GFP_NOWARN) set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook mm/page_alloc.c:2165 [inline] prep_new_page+0x18f/0x370 mm/page_alloc.c:2171 get_page_from_freelist+0x2d13/0x2d90 mm/page_alloc.c:3794 __alloc_pages_nodemask+0x393/0x840 mm/page_alloc.c:4893 __alloc_pages include/linux/gfp.h:503 [inline] __alloc_pages_node include/linux/gfp.h:516 [inline] alloc_pages_node include/linux/gfp.h:530 [inline] pcpu_alloc_pages mm/percpu-vm.c:94 [inline] pcpu_populate_chunk+0x1bb/0xd00 mm/percpu-vm.c:284 pcpu_alloc+0x79e/0x1050 mm/percpu.c:1714 prealloc_init+0x238/0x800 kernel/bpf/hashtab.c:154 htab_map_alloc+0x638/0x930 kernel/bpf/hashtab.c:382 find_and_alloc_map kernel/bpf/syscall.c:122 [inline] map_create kernel/bpf/syscall.c:573 [inline] __do_sys_bpf kernel/bpf/syscall.c:2873 [inline] __se_sys_bpf+0x3291/0xbcb0 kernel/bpf/syscall.c:2849 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x5c/0xc1 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1176 [inline] free_pcp_prepare mm/page_alloc.c:1233 [inline] free_unref_page_prepare+0x297/0x380 mm/page_alloc.c:3085 free_unref_page mm/page_alloc.c:3134 [inline] free_the_page mm/page_alloc.c:4953 [inline] __free_pages+0xaf/0x140 mm/page_alloc.c:4961 pcpu_free_pages mm/percpu-vm.c:64 [inline] pcpu_depopulate_chunk mm/percpu-vm.c:328 [inline] pcpu_balance_workfn+0x940/0x1450 mm/percpu.c:1865 process_one_work+0x765/0xd20 kernel/workqueue.c:2290 worker_thread+0xaef/0x1470 kernel/workqueue.c:2436 kthread+0x2da/0x360 kernel/kthread.c:288 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:354 Memory state around the buggy address: ffff8881d5b23080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff8881d5b23100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff8881d5b23180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff8881d5b23200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff8881d5b23280: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ================================================================== BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor instruction fetch in kernel mode #PF: error_code(0x0010) - not-present page PGD 0 P4D 0 Oops: 0010 [#1] PREEMPT SMP KASAN CPU: 1 PID: 0 Comm: swapper/1 Tainted: G B 5.4.276-syzkaller-00021-g58de09405d1e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 RIP: 0010:0x0 Code: Bad RIP value. RSP: 0018:ffff8881f6f09d18 EFLAGS: 00010202 RAX: ffffffff8154d48a RBX: 0000000000000101 RCX: ffff8881f5dcde80 RDX: 0000000080000101 RSI: 0000000000000000 RDI: ffff8881d5b231c0 RBP: ffff8881f6f09ec8 R08: ffffffff8154d0ce R09: 0000000000000003 R10: ffffffffffffffff R11: dffffc0000000001 R12: 00000000ffff98e8 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8881d5b231c0 FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 00000001e03af000 CR4: 00000000003406a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: call_timer_fn+0x36/0x390 kernel/time/timer.c:1448 expire_timers kernel/time/timer.c:1493 [inline] __run_timers+0x879/0xbe0 kernel/time/timer.c:1817 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1830 __do_softirq+0x23b/0x6b7 kernel/softirq.c:292 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0x195/0x1c0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:539 [inline] smp_apic_timer_interrupt+0x11a/0x460 arch/x86/kernel/apic/apic.c:1149 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:834 RIP: 0010:default_idle+0x1f/0x30 arch/x86/kernel/process.c:573 Code: 90 90 90 90 90 90 90 90 90 90 90 e8 2b 62 e0 fd bf 01 00 00 00 89 c6 e8 3f ab d7 fc 0f 1f 44 00 00 0f 00 2d a3 b8 53 00 fb f4 0c 62 e0 fd bf ff ff ff ff 89 c6 e9 20 ab d7 fc 41 57 41 56 53 RSP: 0018:ffff8881f5dffd78 EFLAGS: 000002d2 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000001 RBX: dffffc0000000000 RCX: ffff8881f5dcde80 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001 RBP: ffff8881f5dffe80 R08: ffffffff82316961 R09: ffffed103ebb9bd1 R10: 0000000000000000 R11: dffffc0000000001 R12: ffffffff864b6ce8 R13: ffff8881f5dcde80 R14: 1ffff1103ebb9bd0 R15: 0000000000000001 default_idle_call kernel/sched/idle.c:94 [inline] cpuidle_idle_call kernel/sched/idle.c:154 [inline] do_idle+0x248/0x660 kernel/sched/idle.c:264 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:356 start_secondary+0x3a5/0x460 arch/x86/kernel/smpboot.c:277 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:241 Modules linked in: CR2: 0000000000000000 ---[ end trace 473e172a95621639 ]--- RIP: 0010:0x0 Code: Bad RIP value. RSP: 0018:ffff8881f6f09d18 EFLAGS: 00010202 RAX: ffffffff8154d48a RBX: 0000000000000101 RCX: ffff8881f5dcde80 RDX: 0000000080000101 RSI: 0000000000000000 RDI: ffff8881d5b231c0 RBP: ffff8881f6f09ec8 R08: ffffffff8154d0ce R09: 0000000000000003 R10: ffffffffffffffff R11: dffffc0000000001 R12: 00000000ffff98e8 R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8881d5b231c0 FS: 0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 00000001e03af000 CR4: 00000000003406a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: f8 clc 1: 48 8d 1c 85 60 3d b6 lea -0x7949c2a0(,%rax,4),%rbx 8: 86 9: 48 89 d8 mov %rbx,%rax c: 48 c1 e8 03 shr $0x3,%rax 10: 49 bd 00 00 00 00 00 movabs $0xdffffc0000000000,%r13 17: fc ff df 1a: 42 0f b6 04 28 movzbl (%rax,%r13,1),%eax 1f: 84 c0 test %al,%al 21: 0f 85 53 18 00 00 jne 0x187a 27: 44 8b 33 mov (%rbx),%r14d * 2a: 44 89 f8 mov %r15d,%eax <-- trapping instruction 2d: ff c0 inc %eax 2f: 48 8d 1c 85 60 3d b6 lea -0x7949c2a0(,%rax,4),%rbx 36: 86 37: 48 89 d8 mov %rbx,%rax 3a: 48 c1 e8 03 shr $0x3,%rax 3e: 42 rex.X 3f: 0f .byte 0xf