================================================================== 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 ffff88808f8fd5b0 by task syz-executor.4/27879 CPU: 0 PID: 27879 Comm: syz-executor.4 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/29/2022 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 sch_direct_xmit+0x2d6/0xf70 net/sched/sch_generic.c:332 qdisc_restart net/sched/sch_generic.c:395 [inline] __qdisc_run+0x4d0/0x1640 net/sched/sch_generic.c:403 __dev_xmit_skb net/core/dev.c:3500 [inline] __dev_queue_xmit+0x1518/0x2e00 net/core/dev.c:3807 neigh_hh_output include/net/neighbour.h:491 [inline] neigh_output include/net/neighbour.h:499 [inline] ip_finish_output2+0xb6d/0x15a0 net/ipv4/ip_output.c:230 ip_finish_output+0xae9/0x10b0 net/ipv4/ip_output.c:318 NF_HOOK_COND include/linux/netfilter.h:278 [inline] ip_output+0x203/0x5f0 net/ipv4/ip_output.c:406 dst_output include/net/dst.h:455 [inline] ip_local_out+0xaf/0x170 net/ipv4/ip_output.c:125 __ip_queue_xmit+0x91e/0x1c10 net/ipv4/ip_output.c:507 __tcp_transmit_skb+0x1b9c/0x3400 net/ipv4/tcp_output.c:1148 __tcp_send_ack.part.0+0x3d9/0x5c0 net/ipv4/tcp_output.c:3643 __tcp_send_ack net/ipv4/tcp_output.c:3649 [inline] tcp_send_ack+0x7d/0xa0 net/ipv4/tcp_output.c:3649 tcp_compressed_ack_kick+0x1ec/0x220 net/ipv4/tcp_timer.c:739 __run_hrtimer kernel/time/hrtimer.c:1465 [inline] __hrtimer_run_queues+0x3f6/0xe60 kernel/time/hrtimer.c:1527 hrtimer_run_softirq+0x172/0x340 kernel/time/hrtimer.c:1541 __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:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline] RIP: 0010:_raw_spin_unlock_irq+0x50/0x80 kernel/locking/spinlock.c:192 Code: c0 98 82 f1 89 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 31 48 83 3d 01 31 d8 01 00 74 25 fb 66 0f 1f 44 00 00 01 00 00 00 e8 26 1b 28 f9 65 8b 05 9f 8d e8 77 85 c0 74 02 5d RSP: 0018:ffff888059627208 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13 RAX: 1ffffffff13e3053 RBX: ffff888053b62200 RCX: 1ffff1100a76c555 RDX: dffffc0000000000 RSI: ffff888053b62ab0 RDI: ffff888053b62a84 RBP: ffff8880ba02b0c0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8880ba02b0c0 R13: ffff8880b5a4c240 R14: ffff88809b668d00 R15: 0000000000000001 finish_lock_switch kernel/sched/core.c:2578 [inline] finish_task_switch+0x146/0x760 kernel/sched/core.c:2678 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] ip6_dst_lookup_tail+0x491/0x19b0 net/ipv6/ip6_output.c:1000 ip6_dst_lookup_flow+0x8c/0x1d0 net/ipv6/ip6_output.c:1120 sctp_v6_get_dst+0x69f/0x1c90 net/sctp/ipv6.c:291 sctp_transport_pmtu+0x245/0x470 net/sctp/transport.c:242 sctp_transport_route+0x15b/0x350 net/sctp/transport.c:319 sctp_assoc_add_peer+0x5bf/0x1050 net/sctp/associola.c:677 sctp_sendmsg_new_asoc+0x580/0x1040 net/sctp/socket.c:1789 sctp_sendmsg+0x1146/0x1580 net/sctp/socket.c:2122 inet_sendmsg+0x132/0x5a0 net/ipv4/af_inet.c:798 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0xc3/0x120 net/socket.c:661 ___sys_sendmsg+0x7bb/0x8e0 net/socket.c:2227 __sys_sendmsg net/socket.c:2265 [inline] __do_sys_sendmsg net/socket.c:2274 [inline] __se_sys_sendmsg net/socket.c:2272 [inline] __x64_sys_sendmsg+0x132/0x220 net/socket.c:2272 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7fa498ee9209 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fa49785e168 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fa498ffbf60 RCX: 00007fa498ee9209 RDX: 0000000000000040 RSI: 0000000020000300 RDI: 0000000000000004 RBP: 00007fa498f43161 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffc6a9b143f R14: 00007fa49785e300 R15: 0000000000022000 Allocated by task 27870: __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 27869: __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 ffff88808f8fcd80 which belongs to the cache kmalloc-4096 of size 4096 The buggy address is located 2096 bytes inside of 4096-byte region [ffff88808f8fcd80, ffff88808f8fdd80) The buggy address belongs to the page: page:ffffea00023e3f00 count:1 mapcount:0 mapping:ffff88813bff0dc0 index:0x0 compound_mapcount: 0 flags: 0xfff00000008100(slab|head) raw: 00fff00000008100 ffffea000265cc08 ffffea0002536d88 ffff88813bff0dc0 raw: 0000000000000000 ffff88808f8fcd80 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88808f8fd480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88808f8fd500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88808f8fd580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88808f8fd600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88808f8fd680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess), 5 bytes skipped: 0: 48 ba 00 00 00 00 00 movabs $0xdffffc0000000000,%rdx 7: fc ff df a: 48 c1 e8 03 shr $0x3,%rax e: 80 3c 10 00 cmpb $0x0,(%rax,%rdx,1) 12: 75 31 jne 0x45 14: 48 83 3d 01 31 d8 01 cmpq $0x0,0x1d83101(%rip) # 0x1d8311d 1b: 00 1c: 74 25 je 0x43 1e: fb sti 1f: 66 0f 1f 44 00 00 nopw 0x0(%rax,%rax,1) * 25: bf 01 00 00 00 mov $0x1,%edi <-- trapping instruction 2a: e8 26 1b 28 f9 callq 0xf9281b55 2f: 65 8b 05 9f 8d e8 77 mov %gs:0x77e88d9f(%rip),%eax # 0x77e88dd5 36: 85 c0 test %eax,%eax 38: 74 02 je 0x3c 3a: 5d pop %rbp