================================================================== BUG: KASAN: use-after-free in __read_once_size include/linux/compiler.h:263 [inline] BUG: KASAN: use-after-free in dev_queue_xmit_nit+0x87e/0xa20 net/core/dev.c:2004 Read of size 8 at addr ffff888092a4f470 by task syz-executor117/25955 CPU: 1 PID: 25955 Comm: syz-executor117 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2ef lib/dump_stack.c:118 print_address_description.cold+0x54/0x219 mm/kasan/report.c:256 kasan_report_error.cold+0x8a/0x1b9 mm/kasan/report.c:354 kasan_report mm/kasan/report.c:412 [inline] __asan_report_load8_noabort+0x88/0x90 mm/kasan/report.c:433 __read_once_size include/linux/compiler.h:263 [inline] dev_queue_xmit_nit+0x87e/0xa20 net/core/dev.c:2004 xmit_one net/core/dev.c:3252 [inline] dev_hard_start_xmit+0xaa/0x920 net/core/dev.c:3272 __dev_queue_xmit+0x269d/0x2e00 net/core/dev.c:3838 neigh_hh_output include/net/neighbour.h:491 [inline] neigh_output include/net/neighbour.h:499 [inline] ip6_finish_output2+0xde7/0x2290 net/ipv6/ip6_output.c:120 ip6_finish_output+0x89b/0x10f0 net/ipv6/ip6_output.c:192 NF_HOOK_COND include/linux/netfilter.h:278 [inline] ip6_output+0x205/0x770 net/ipv6/ip6_output.c:209 dst_output include/net/dst.h:455 [inline] NF_HOOK include/linux/netfilter.h:289 [inline] ndisc_send_skb+0xa24/0x1720 net/ipv6/ndisc.c:491 ndisc_send_rs+0x131/0x690 net/ipv6/ndisc.c:685 addrconf_rs_timer+0x384/0x6a0 net/ipv6/addrconf.c:3835 call_timer_fn+0x177/0x700 kernel/time/timer.c:1338 expire_timers+0x243/0x4e0 kernel/time/timer.c:1375 __run_timers kernel/time/timer.c:1696 [inline] run_timer_softirq+0x21c/0x670 kernel/time/timer.c:1709 __do_softirq+0x265/0x980 kernel/softirq.c:292 invoke_softirq kernel/softirq.c:372 [inline] irq_exit+0x215/0x260 kernel/softirq.c:412 exiting_irq arch/x86/include/asm/apic.h:536 [inline] smp_apic_timer_interrupt+0x136/0x550 arch/x86/kernel/apic/apic.c:1098 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:789 [inline] RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xa3/0xe0 kernel/locking/spinlock.c:184 Code: 48 c7 c0 88 82 f1 89 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 2f 48 83 3d 7c 31 d8 01 00 74 15 48 89 df 57 9d <0f> 1f 44 00 00 eb b2 e8 fb eb e6 f8 eb c0 0f 0b 0f 0b 48 c7 c7 88 RSP: 0018:ffff888092137680 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13 RAX: 1ffffffff13e3051 RBX: 0000000000000286 RCX: 0000000000000000 RDX: dffffc0000000000 RSI: ffff8880a6534b08 RDI: 0000000000000286 RBP: ffffffff8d3e1408 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: dead000000000200 R13: ffff88809abc0000 R14: 0000000000000000 R15: dffffc0000000000 __debug_check_no_obj_freed lib/debugobjects.c:798 [inline] debug_check_no_obj_freed+0x201/0x490 lib/debugobjects.c:817 free_pages_prepare mm/page_alloc.c:1056 [inline] __free_pages_ok+0x22d/0xd30 mm/page_alloc.c:1279 free_thread_stack kernel/fork.c:270 [inline] release_task_stack kernel/fork.c:385 [inline] put_task_stack+0xd2/0x1f0 kernel/fork.c:396 finish_task_switch+0x523/0x760 kernel/sched/core.c:2710 context_switch kernel/sched/core.c:2831 [inline] __schedule+0x88f/0x2040 kernel/sched/core.c:3517 preempt_schedule_common+0x45/0xc0 kernel/sched/core.c:3641 ___preempt_schedule+0x16/0x18 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline] _raw_spin_unlock_irqrestore+0xaf/0xe0 kernel/locking/spinlock.c:184 __rcu_read_unlock+0x158/0x160 kernel/rcu/tree_plugin.h:428 rcu_read_unlock include/linux/rcupdate.h:680 [inline] is_bpf_text_address+0xdf/0x1b0 kernel/bpf/core.c:548 kernel_text_address kernel/extable.c:152 [inline] kernel_text_address+0xbd/0xf0 kernel/extable.c:122 __kernel_text_address+0x9/0x30 kernel/extable.c:107 unwind_get_return_address arch/x86/kernel/unwind_orc.c:297 [inline] unwind_get_return_address+0x51/0x90 arch/x86/kernel/unwind_orc.c:292 __save_stack_trace+0xaf/0x190 arch/x86/kernel/stacktrace.c:45 save_stack mm/kasan/kasan.c:448 [inline] set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xeb/0x160 mm/kasan/kasan.c:553 kmem_cache_alloc+0x122/0x370 mm/slab.c:3559 __d_alloc+0x2b/0xa10 fs/dcache.c:1612 d_alloc_pseudo+0x19/0x70 fs/dcache.c:1743 alloc_file_pseudo+0xc6/0x250 fs/file_table.c:224 sock_alloc_file+0x48/0x180 net/socket.c:406 sock_map_fd net/socket.c:429 [inline] __sys_socket+0x13d/0x200 net/socket.c:1462 __do_sys_socket net/socket.c:1467 [inline] __se_sys_socket net/socket.c:1465 [inline] __x64_sys_socket+0x6f/0xb0 net/socket.c:1465 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7fb022342e89 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 31 19 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fb021ae01f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000029 RAX: ffffffffffffffda RBX: 0000000000000014 RCX: 00007fb022342e89 RDX: 0000000000000300 RSI: 0000000000000002 RDI: 0000000000000011 RBP: 00007fb0223cb280 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fb0223cb28c R13: 00007fff4176abaf R14: 00007fb021ae0300 R15: 0000000000022000 Allocated by task 25951: __do_kmalloc mm/slab.c:3727 [inline] __kmalloc+0x15a/0x3c0 mm/slab.c:3736 kmalloc include/linux/slab.h:520 [inline] sk_prot_alloc+0x1e2/0x2d0 net/core/sock.c:1483 sk_alloc+0x36/0xec0 net/core/sock.c:1537 packet_create+0x117/0x850 net/packet/af_packet.c:3259 __sock_create+0x3d8/0x740 net/socket.c:1365 sock_create net/socket.c:1416 [inline] __sys_socket+0xef/0x200 net/socket.c:1458 __do_sys_socket net/socket.c:1467 [inline] __se_sys_socket net/socket.c:1465 [inline] __x64_sys_socket+0x6f/0xb0 net/socket.c:1465 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 25959: __cache_free mm/slab.c:3503 [inline] kfree+0xcc/0x210 mm/slab.c:3822 sk_prot_free net/core/sock.c:1520 [inline] __sk_destruct+0x684/0x8a0 net/core/sock.c:1602 sk_destruct net/core/sock.c:1617 [inline] __sk_free+0x165/0x3b0 net/core/sock.c:1628 sk_free+0x3b/0x50 net/core/sock.c:1639 sock_put include/net/sock.h:1713 [inline] packet_release+0x890/0xb70 net/packet/af_packet.c:3088 __sock_release+0xcd/0x2a0 net/socket.c:599 sock_close+0x15/0x20 net/socket.c:1214 __fput+0x2ce/0x890 fs/file_table.c:278 task_work_run+0x148/0x1c0 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0xbf3/0x2be0 kernel/exit.c:870 do_group_exit+0x125/0x310 kernel/exit.c:967 get_signal+0x3f2/0x1f70 kernel/signal.c:2589 do_signal+0x8f/0x1670 arch/x86/kernel/signal.c:799 exit_to_usermode_loop+0x204/0x2a0 arch/x86/entry/common.c:163 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline] syscall_return_slowpath arch/x86/entry/common.c:271 [inline] do_syscall_64+0x538/0x620 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff888092a4ec40 which belongs to the cache kmalloc-4096 of size 4096 The buggy address is located 2096 bytes inside of 4096-byte region [ffff888092a4ec40, ffff888092a4fc40) The buggy address belongs to the page: page:ffffea00024a9380 count:1 mapcount:0 mapping:ffff88813bff0dc0 index:0x0 compound_mapcount: 0 flags: 0xfff00000008100(slab|head) raw: 00fff00000008100 ffffea0002953d88 ffffea0002408e88 ffff88813bff0dc0 raw: 0000000000000000 ffff888092a4ec40 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888092a4f300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888092a4f380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888092a4f400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888092a4f480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888092a4f500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 48 c7 c0 88 82 f1 89 mov $0xffffffff89f18288,%rax 7: 48 ba 00 00 00 00 00 movabs $0xdffffc0000000000,%rdx e: fc ff df 11: 48 c1 e8 03 shr $0x3,%rax 15: 80 3c 10 00 cmpb $0x0,(%rax,%rdx,1) 19: 75 2f jne 0x4a 1b: 48 83 3d 7c 31 d8 01 cmpq $0x0,0x1d8317c(%rip) # 0x1d8319f 22: 00 23: 74 15 je 0x3a 25: 48 89 df mov %rbx,%rdi 28: 57 push %rdi 29: 9d popfq * 2a: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) <-- trapping instruction 2f: eb b2 jmp 0xffffffe3 31: e8 fb eb e6 f8 callq 0xf8e6ec31 36: eb c0 jmp 0xfffffff8 38: 0f 0b ud2 3a: 0f 0b ud2 3c: 48 rex.W 3d: c7 .byte 0xc7 3e: c7 (bad) 3f: 88 .byte 0x88