BUG: kernel NULL pointer dereference, address: 0000000000000008 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 120d05067 P4D 120d05067 PUD 121050067 PMD 0 Oops: 0000 [#1] PREEMPT SMP CPU: 0 PID: 10754 Comm: syz-executor.4 Not tainted 5.10.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:compound_head include/linux/page-flags.h:185 [inline] RIP: 0010:put_page include/linux/mm.h:1180 [inline] RIP: 0010:__skb_frag_unref include/linux/skbuff.h:3019 [inline] RIP: 0010:skb_release_data+0x67/0x180 net/core/skbuff.c:604 Code: 85 0b 01 00 00 31 db 80 7d 02 00 49 89 fc 75 0e eb 4d 0f b6 45 02 48 83 c3 01 39 d8 7e 41 48 89 d8 48 c1 e0 04 48 8b 7c 05 30 <48> 8b 47 08 48 8d 50 ff a8 01 48 0f 45 fa 0f 1f 44 00 00 8b 47 34 RSP: 0018:ffffc90000003d98 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000302 RSI: ffffffff840a0b07 RDI: 0000000000000000 RBP: ffff8881212c7cc0 R08: 0000000000000001 R09: 0000000000000000 R10: ffff888121170d98 R11: 0000000000000000 R12: ffff88810d2d4a00 R13: ffffc90000003e1b R14: ffffffffffffffa3 R15: ffff88810d2d4a00 FS: 00007f260d8e9700(0000) GS:ffff88813bc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000008 CR3: 00000001211f0000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __kfree_skb net/core/skbuff.c:678 [inline] kfree_skb+0x4a/0x140 net/core/skbuff.c:696 validate_xmit_skb+0x275/0x2f0 net/core/dev.c:3667 __dev_queue_xmit+0x77b/0xd30 net/core/dev.c:4131 mrp_queue_xmit net/802/mrp.c:351 [inline] mrp_join_timer+0x48/0x70 net/802/mrp.c:595 call_timer_fn+0xa5/0x300 kernel/time/timer.c:1410 expire_timers kernel/time/timer.c:1455 [inline] __run_timers kernel/time/timer.c:1747 [inline] run_timer_softirq+0x217/0x5c0 kernel/time/timer.c:1760 __do_softirq+0xe9/0x590 kernel/softirq.c:298 asm_call_irq_on_stack+0xf/0x20 __run_on_irqstack arch/x86/include/asm/irq_stack.h:26 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:77 [inline] do_softirq_own_stack+0x7c/0xa0 arch/x86/kernel/irq_64.c:77 invoke_softirq kernel/softirq.c:393 [inline] __irq_exit_rcu kernel/softirq.c:423 [inline] irq_exit_rcu+0xea/0x110 kernel/softirq.c:435 sysvec_apic_timer_interrupt+0x57/0xf0 arch/x86/kernel/apic/apic.c:1091 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:631 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:653 [inline] RIP: 0010:console_unlock+0x4d7/0x620 kernel/printk/printk.c:2507 Code: c0 89 71 84 e8 3a 02 ff ff e8 a5 1c 00 00 4d 85 e4 0f 85 ba 00 00 00 48 83 3d ec 01 48 03 00 0f 84 27 01 00 00 48 89 df 57 9d <0f> 1f 44 00 00 8b 44 24 0c 85 c0 0f 84 c4 fb ff ff 31 d2 be ce 09 RSP: 0018:ffffc9000a203470 EFLAGS: 00000282 RAX: 0000000000040ef1 RBX: 0000000000000282 RCX: 0000000000000006 RDX: 0000000000000000 RSI: ffffffff84154d1b RDI: 0000000000000282 RBP: ffffffff84cc30c8 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000200 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 vprintk_emit+0x156/0x380 kernel/printk/printk.c:2028 printk+0x53/0x6a kernel/printk/printk.c:2076 addrconf_notify+0xb94/0xba0 net/ipv6/addrconf.c:3567 notifier_call_chain+0x2f/0x90 kernel/notifier.c:83 __dev_notify_flags+0xe3/0xf0 net/core/dev.c:8475 rtnl_configure_link+0x83/0x90 net/core/rtnetlink.c:3133 __rtnl_newlink+0x685/0x8a0 net/core/rtnetlink.c:3460 rtnl_newlink+0x3e/0x60 net/core/rtnetlink.c:3500 rtnetlink_rcv_msg+0x173/0x480 net/core/rtnetlink.c:5562 netlink_rcv_skb+0x49/0xf0 net/netlink/af_netlink.c:2494 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline] netlink_unicast+0x19a/0x270 net/netlink/af_netlink.c:1330 netlink_sendmsg+0x248/0x480 net/netlink/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0x2b/0x40 net/socket.c:671 ____sys_sendmsg+0x1ed/0x230 net/socket.c:2353 ___sys_sendmsg+0x77/0xb0 net/socket.c:2407 __sys_sendmsg+0x52/0xa0 net/socket.c:2440 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45d5f9 Code: 5d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 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 0f 83 2b b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f260d8e8c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 000000000002cf00 RCX: 000000000045d5f9 RDX: 0000000000000000 RSI: 0000000020000280 RDI: 0000000000000005 RBP: 000000000118d020 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118cfec R13: 00007fff8ea50f9f R14: 00007f260d8e99c0 R15: 000000000118cfec Modules linked in: CR2: 0000000000000008 ---[ end trace dff33cf1898a24a8 ]--- RIP: 0010:compound_head include/linux/page-flags.h:185 [inline] RIP: 0010:put_page include/linux/mm.h:1180 [inline] RIP: 0010:__skb_frag_unref include/linux/skbuff.h:3019 [inline] RIP: 0010:skb_release_data+0x67/0x180 net/core/skbuff.c:604 Code: 85 0b 01 00 00 31 db 80 7d 02 00 49 89 fc 75 0e eb 4d 0f b6 45 02 48 83 c3 01 39 d8 7e 41 48 89 d8 48 c1 e0 04 48 8b 7c 05 30 <48> 8b 47 08 48 8d 50 ff a8 01 48 0f 45 fa 0f 1f 44 00 00 8b 47 34 RSP: 0018:ffffc90000003d98 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000302 RSI: ffffffff840a0b07 RDI: 0000000000000000 RBP: ffff8881212c7cc0 R08: 0000000000000001 R09: 0000000000000000 R10: ffff888121170d98 R11: 0000000000000000 R12: ffff88810d2d4a00 R13: ffffc90000003e1b R14: ffffffffffffffa3 R15: ffff88810d2d4a00 FS: 00007f260d8e9700(0000) GS:ffff88813bc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000008 CR3: 00000001211f0000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400