netlink: 12 bytes leftover after parsing attributes in process `syz-executor.2'. device vlan2 entered promiscuous mode team1: Port device vlan2 added ================================================================== BUG: KASAN: use-after-free in br_dev_xmit+0x12b3/0x13e0 net/bridge/br_device.c:68 Read of size 2 at addr ffff88809016170e by task syz-executor.0/13319 CPU: 1 PID: 13319 Comm: syz-executor.0 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_load_n_noabort+0x8b/0xa0 mm/kasan/report.c:443 br_dev_xmit+0x12b3/0x13e0 net/bridge/br_device.c:68 __netdev_start_xmit include/linux/netdevice.h:4349 [inline] netdev_start_xmit include/linux/netdevice.h:4363 [inline] xmit_one net/core/dev.c:3256 [inline] dev_hard_start_xmit+0x1a8/0x920 net/core/dev.c:3272 __dev_queue_xmit+0x269d/0x2e00 net/core/dev.c:3838 vlan_dev_hard_start_xmit+0x38f/0x800 net/8021q/vlan_dev.c:131 __netdev_start_xmit include/linux/netdevice.h:4349 [inline] netdev_start_xmit include/linux/netdevice.h:4363 [inline] xmit_one net/core/dev.c:3256 [inline] dev_hard_start_xmit+0x1a8/0x920 net/core/dev.c:3272 __dev_queue_xmit+0x269d/0x2e00 net/core/dev.c:3838 neigh_connected_output+0x3e8/0x5e0 net/core/neighbour.c:1403 neigh_output include/net/neighbour.h:501 [inline] ip6_finish_output2+0x113d/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] mld_sendpack+0x674/0x1060 net/ipv6/mcast.c:1681 mld_send_cr net/ipv6/mcast.c:1977 [inline] mld_ifc_timer_expire+0x616/0xdf0 net/ipv6/mcast.c:2476 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:ffff888043cff580 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13 RAX: 1ffffffff13e3051 RBX: 0000000000000286 RCX: 0000000000000000 RDX: dffffc0000000000 RSI: 0000000000000001 RDI: 0000000000000286 RBP: ffffffff8d3f5208 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: dead000000000200 R13: ffff888030600000 R14: 0000000000000007 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 release_pages+0xab5/0x15a0 mm/swap.c:768 tlb_flush_mmu_free mm/memory.c:261 [inline] zap_pte_range mm/memory.c:1417 [inline] zap_pmd_range mm/memory.c:1463 [inline] zap_pud_range mm/memory.c:1492 [inline] zap_p4d_range mm/memory.c:1513 [inline] unmap_page_range+0x221f/0x2c50 mm/memory.c:1534 unmap_single_vma+0x198/0x300 mm/memory.c:1579 unmap_vmas+0xa9/0x180 mm/memory.c:1609 exit_mmap+0x2b9/0x530 mm/mmap.c:3093 __mmput kernel/fork.c:1016 [inline] mmput+0x14e/0x4a0 kernel/fork.c:1037 exit_mm kernel/exit.c:549 [inline] do_exit+0xaec/0x2be0 kernel/exit.c:857 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 RIP: 0033:0x7fd56119d059 Code: Bad RIP value. RSP: 002b:00007fd55fad0218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007fd5612b0108 RCX: 00007fd56119d059 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fd5612b0108 RBP: 00007fd5612b0100 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fd5612b010c R13: 00007ffcc65a7fdf R14: 00007fd55fad0300 R15: 0000000000022000 Allocated by task 13319: __do_kmalloc_node mm/slab.c:3689 [inline] __kmalloc_node_track_caller+0x4c/0x70 mm/slab.c:3703 __kmalloc_reserve net/core/skbuff.c:137 [inline] __alloc_skb+0xae/0x560 net/core/skbuff.c:205 alloc_skb include/linux/skbuff.h:995 [inline] alloc_skb_with_frags+0x92/0x570 net/core/skbuff.c:5333 sock_alloc_send_pskb+0x6e1/0x830 net/core/sock.c:2108 mld_newpack+0x1d2/0x760 net/ipv6/mcast.c:1609 add_grhead+0x265/0x330 net/ipv6/mcast.c:1712 add_grec+0xe3c/0x10b0 net/ipv6/mcast.c:1843 mld_send_cr net/ipv6/mcast.c:1969 [inline] mld_ifc_timer_expire+0x5a2/0xdf0 net/ipv6/mcast.c:2476 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 Freed by task 13319: __cache_free mm/slab.c:3503 [inline] kfree+0xcc/0x210 mm/slab.c:3822 skb_free_head net/core/skbuff.c:563 [inline] pskb_expand_head+0x327/0xf20 net/core/skbuff.c:1506 __skb_cow include/linux/skbuff.h:2977 [inline] skb_cow_head include/linux/skbuff.h:3011 [inline] __vlan_insert_inner_tag include/linux/if_vlan.h:346 [inline] vlan_insert_inner_tag include/linux/if_vlan.h:416 [inline] vlan_insert_tag include/linux/if_vlan.h:441 [inline] vlan_insert_tag_set_proto include/linux/if_vlan.h:460 [inline] __allowed_ingress net/bridge/br_vlan.c:437 [inline] br_allowed_ingress+0x376/0xed0 net/bridge/br_vlan.c:514 br_dev_xmit+0x3e5/0x13e0 net/bridge/br_device.c:64 __netdev_start_xmit include/linux/netdevice.h:4349 [inline] netdev_start_xmit include/linux/netdevice.h:4363 [inline] xmit_one net/core/dev.c:3256 [inline] dev_hard_start_xmit+0x1a8/0x920 net/core/dev.c:3272 __dev_queue_xmit+0x269d/0x2e00 net/core/dev.c:3838 vlan_dev_hard_start_xmit+0x38f/0x800 net/8021q/vlan_dev.c:131 __netdev_start_xmit include/linux/netdevice.h:4349 [inline] netdev_start_xmit include/linux/netdevice.h:4363 [inline] xmit_one net/core/dev.c:3256 [inline] dev_hard_start_xmit+0x1a8/0x920 net/core/dev.c:3272 __dev_queue_xmit+0x269d/0x2e00 net/core/dev.c:3838 neigh_connected_output+0x3e8/0x5e0 net/core/neighbour.c:1403 neigh_output include/net/neighbour.h:501 [inline] ip6_finish_output2+0x113d/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] mld_sendpack+0x674/0x1060 net/ipv6/mcast.c:1681 mld_send_cr net/ipv6/mcast.c:1977 [inline] mld_ifc_timer_expire+0x616/0xdf0 net/ipv6/mcast.c:2476 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 The buggy address belongs to the object at ffff888090161700 which belongs to the cache kmalloc-2048 of size 2048 The buggy address is located 14 bytes inside of 2048-byte region [ffff888090161700, ffff888090161f00) The buggy address belongs to the page: page:ffffea0002405800 count:1 mapcount:0 mapping:ffff88813bff0c40 index:0x0 compound_mapcount: 0 flags: 0xfff00000008100(slab|head) raw: 00fff00000008100 ffffea00026c7e08 ffffea0001111388 ffff88813bff0c40 raw: 0000000000000000 ffff888090160600 0000000100000003 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888090161600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888090161680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888090161700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888090161780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888090161800: 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