skbuff: skb_over_panic: text:ffffffff843b87ee len:76 put:20 head:ffff88816184f000 data:ffff88816184f040 tail:0x8c end:0x80 dev:ip6gretap1 ------------[ cut here ]------------ kernel BUG at net/core/skbuff.c:110! invalid opcode: 0000 [#1] PREEMPT SMP KASAN CPU: 1 PID: 5184 Comm: syz-executor.0 Not tainted 5.10.93-syzkaller-01028-g0347b1658399 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:skb_panic+0x14f/0x160 net/core/skbuff.c:106 Code: 87 85 48 8b 75 c0 48 8b 55 b8 8b 4d d4 44 8b 45 d0 4c 8b 4d c8 b8 00 00 00 00 53 41 56 41 55 41 54 e8 0c 3f 89 fd 48 83 c4 20 <0f> 0b 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 55 48 89 e5 41 RSP: 0018:ffffc90000160af8 EFLAGS: 00010282 RAX: 0000000000000089 RBX: ffff8881179d8000 RCX: d2e0eac952fc1200 RDX: 0000000000000502 RSI: 0000000000000502 RDI: 0000000000000000 RBP: ffffc90000160b40 R08: ffffffff815457c8 R09: ffffed103ee2a5d8 R10: ffffed103ee2a5d8 R11: 0000000000000000 R12: ffff88816184f040 R13: 000000000000008c R14: 0000000000000080 R15: dffffc0000000000 FS: 00007ff924776700(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555555d28af8 CR3: 000000011926e000 CR4: 00000000003506a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: skb_over_panic+0x2c/0x30 net/core/skbuff.c:115 skb_put+0x205/0x210 net/core/skbuff.c:1877 add_grhead net/ipv6/mcast.c:1711 [inline] add_grec+0xf5e/0x1370 net/ipv6/mcast.c:1838 mld_send_cr net/ipv6/mcast.c:1964 [inline] mld_ifc_timer_expire+0x781/0xc50 net/ipv6/mcast.c:2471 call_timer_fn+0x35/0x280 kernel/time/timer.c:1420 expire_timers+0x21f/0x3b0 kernel/time/timer.c:1465 __run_timers+0x548/0x680 kernel/time/timer.c:1756 run_timer_softirq+0x69/0xf0 kernel/time/timer.c:1769 __do_softirq+0x27e/0x598 kernel/softirq.c:305 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+0x60/0x80 arch/x86/kernel/irq_64.c:77 invoke_softirq kernel/softirq.c:402 [inline] __irq_exit_rcu+0x128/0x150 kernel/softirq.c:432 irq_exit_rcu+0x9/0x10 kernel/softirq.c:444 sysvec_apic_timer_interrupt+0xbf/0xe0 arch/x86/kernel/apic/apic.c:1095 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:635 RIP: 0010:mpage_map_and_submit_extent fs/ext4/inode.c:2471 [inline] RIP: 0010:ext4_writepages+0x15c1/0x3950 fs/ext4/inode.c:2822 Code: e8 03 42 80 3c 20 00 4c 89 e3 74 08 4c 89 f7 e8 65 2b c4 ff 4d 89 3e 48 8b bc 24 a8 00 00 00 4c 89 ee e8 b2 7d 00 00 41 89 c6 <31> ff 89 c6 e8 16 3a 8a ff 45 85 f6 0f 88 f0 0a 00 00 ba 80 00 00 RSP: 0018:ffffc90008817040 EFLAGS: 00000282 RAX: 0000000000000000 RBX: dffffc0000000000 RCX: 0000000000040000 RDX: ffffc90000f19000 RSI: 0000000000003697 RDI: 0000000000003698 RBP: ffffc90008817430 R08: ffffffff81e337ab R09: ffffed102c0a3984 R10: ffffed102c0a3984 R11: 0000000000000000 R12: dffffc0000000000 R13: ffffc90008817300 R14: 0000000000000000 R15: 0000000000001000 do_writepages+0x13a/0x280 mm/page-writeback.c:2358 __filemap_fdatawrite_range+0x356/0x420 mm/filemap.c:427 filemap_write_and_wait_range+0x64/0xe0 mm/filemap.c:660 __iomap_dio_rw+0x621/0x10c0 fs/iomap/direct-io.c:495 iomap_dio_rw+0x35/0x80 fs/iomap/direct-io.c:611 ext4_dio_read_iter fs/ext4/file.c:79 [inline] ext4_file_read_iter+0x3c8/0x4d0 fs/ext4/file.c:131 call_read_iter include/linux/fs.h:1941 [inline] generic_file_splice_read+0x479/0x760 fs/splice.c:311 do_splice_to fs/splice.c:788 [inline] splice_direct_to_actor+0x42c/0xbc0 fs/splice.c:867 do_splice_direct+0x28b/0x3e0 fs/splice.c:976 do_sendfile+0x914/0x1390 fs/read_write.c:1257 __do_sys_sendfile64 fs/read_write.c:1318 [inline] __se_sys_sendfile64 fs/read_write.c:1304 [inline] __x64_sys_sendfile64+0x1c4/0x220 fs/read_write.c:1304 do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7ff925600059 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:00007ff924776168 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007ff925712f60 RCX: 00007ff925600059 RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000004 RBP: 00007ff92565a08d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000010000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffcf04db48f R14: 00007ff924776300 R15: 0000000000022000 Modules linked in: ---[ end trace 333cac415585c3e9 ]--- RIP: 0010:skb_panic+0x14f/0x160 net/core/skbuff.c:106 Code: 87 85 48 8b 75 c0 48 8b 55 b8 8b 4d d4 44 8b 45 d0 4c 8b 4d c8 b8 00 00 00 00 53 41 56 41 55 41 54 e8 0c 3f 89 fd 48 83 c4 20 <0f> 0b 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 55 48 89 e5 41 RSP: 0018:ffffc90000160af8 EFLAGS: 00010282 RAX: 0000000000000089 RBX: ffff8881179d8000 RCX: d2e0eac952fc1200 RDX: 0000000000000502 RSI: 0000000000000502 RDI: 0000000000000000 RBP: ffffc90000160b40 R08: ffffffff815457c8 R09: ffffed103ee2a5d8 R10: ffffed103ee2a5d8 R11: 0000000000000000 R12: ffff88816184f040 R13: 000000000000008c R14: 0000000000000080 R15: dffffc0000000000 FS: 00007ff924776700(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555555d28af8 CR3: 000000011926e000 CR4: 00000000003506a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: e8 03 42 80 3c callq 0x3c804208 5: 20 00 and %al,(%rax) 7: 4c 89 e3 mov %r12,%rbx a: 74 08 je 0x14 c: 4c 89 f7 mov %r14,%rdi f: e8 65 2b c4 ff callq 0xffc42b79 14: 4d 89 3e mov %r15,(%r14) 17: 48 8b bc 24 a8 00 00 mov 0xa8(%rsp),%rdi 1e: 00 1f: 4c 89 ee mov %r13,%rsi 22: e8 b2 7d 00 00 callq 0x7dd9 27: 41 89 c6 mov %eax,%r14d * 2a: 31 ff xor %edi,%edi <-- trapping instruction 2c: 89 c6 mov %eax,%esi 2e: e8 16 3a 8a ff callq 0xff8a3a49 33: 45 85 f6 test %r14d,%r14d 36: 0f 88 f0 0a 00 00 js 0xb2c 3c: ba .byte 0xba 3d: 80 00 00 addb $0x0,(%rax)