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BUG: KASAN: use-after-free in __get_unaligned_cpu32 include/linux/unaligned/packed_struct.h:19 [inline]
BUG: KASAN: use-after-free in mc_hash drivers/net/macvlan.c:255 [inline]
BUG: KASAN: use-after-free in macvlan_broadcast+0x4b9/0x5c0 drivers/net/macvlan.c:281
Read of size 4 at addr ffff88809e79f801 by task syz-executor.0/9478

CPU: 0 PID: 9478 Comm: syz-executor.0 Not tainted 4.14.162-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x142/0x197 lib/dump_stack.c:58
 print_address_description.cold+0x7c/0x1dc mm/kasan/report.c:252
 kasan_report_error mm/kasan/report.c:351 [inline]
 kasan_report mm/kasan/report.c:409 [inline]
 kasan_report.cold+0xa9/0x2af mm/kasan/report.c:393
 __asan_report_load_n_noabort+0xf/0x20 mm/kasan/report.c:440
 __get_unaligned_cpu32 include/linux/unaligned/packed_struct.h:19 [inline]
 mc_hash drivers/net/macvlan.c:255 [inline]
 macvlan_broadcast+0x4b9/0x5c0 drivers/net/macvlan.c:281
 macvlan_queue_xmit drivers/net/macvlan.c:522 [inline]
 macvlan_start_xmit+0x56b/0x72d drivers/net/macvlan.c:565
 __netdev_start_xmit include/linux/netdevice.h:4038 [inline]
 netdev_start_xmit include/linux/netdevice.h:4047 [inline]
 packet_direct_xmit+0x431/0x640 net/packet/af_packet.c:269
 packet_snd net/packet/af_packet.c:2994 [inline]
 packet_sendmsg+0x1dd4/0x5a60 net/packet/af_packet.c:3019
 sock_sendmsg_nosec net/socket.c:646 [inline]
 sock_sendmsg+0xce/0x110 net/socket.c:656
 SYSC_sendto+0x206/0x310 net/socket.c:1763
 SyS_sendto+0x40/0x50 net/socket.c:1731
 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45af49
RSP: 002b:00007f7d774fbc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 000000000045af49
RDX: 000000000000000e RSI: 0000000020000080 RDI: 0000000000000003
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f7d774fc6d4
R13: 00000000004ca8a7 R14: 00000000004e3ac0 R15: 00000000ffffffff

Allocated by task 7241:
 save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59
 save_stack+0x45/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_kmalloc mm/kasan/kasan.c:551 [inline]
 kasan_kmalloc+0xce/0xf0 mm/kasan/kasan.c:529
 kasan_slab_alloc+0xf/0x20 mm/kasan/kasan.c:489
 kmem_cache_alloc+0x12e/0x780 mm/slab.c:3552
 dup_mmap kernel/fork.c:647 [inline]
 dup_mm kernel/fork.c:1199 [inline]
 copy_mm kernel/fork.c:1254 [inline]
 copy_process.part.0+0x455d/0x6a70 kernel/fork.c:1771
 copy_process kernel/fork.c:1586 [inline]
 _do_fork+0x19e/0xce0 kernel/fork.c:2070
 SYSC_clone kernel/fork.c:2180 [inline]
 SyS_clone+0x37/0x50 kernel/fork.c:2174
 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7

Freed by task 9033:
 save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59
 save_stack+0x45/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_slab_free+0x75/0xc0 mm/kasan/kasan.c:524
 __cache_free mm/slab.c:3496 [inline]
 kmem_cache_free+0x83/0x2b0 mm/slab.c:3758
 remove_vma+0x161/0x1b0 mm/mmap.c:177
 exit_mmap+0x314/0x4e0 mm/mmap.c:3073
 __mmput kernel/fork.c:930 [inline]
 mmput+0x114/0x440 kernel/fork.c:951
 exit_mm kernel/exit.c:545 [inline]
 do_exit+0x6fc/0x2c80 kernel/exit.c:841
 do_group_exit+0x111/0x330 kernel/exit.c:951
 get_signal+0x381/0x1cd0 kernel/signal.c:2413
 do_signal+0x86/0x19a0 arch/x86/kernel/signal.c:814
 exit_to_usermode_loop+0x15c/0x220 arch/x86/entry/common.c:160
 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:270 [inline]
 do_syscall_64+0x4bc/0x640 arch/x86/entry/common.c:297
 entry_SYSCALL_64_after_hwframe+0x42/0xb7

The buggy address belongs to the object at ffff88809e79f778
 which belongs to the cache vm_area_struct of size 200
The buggy address is located 137 bytes inside of
 200-byte region [ffff88809e79f778, ffff88809e79f840)
The buggy address belongs to the page:
page:ffffea000279e7c0 count:1 mapcount:0 mapping:ffff88809e79f040 index:0x0
flags: 0xfffe0000000100(slab)
raw: 00fffe0000000100 ffff88809e79f040 0000000000000000 000000010000000f
raw: ffffea00024aade0 ffffea0002446860 ffff88821f830c40 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88809e79f700: fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc fb
 ffff88809e79f780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88809e79f800: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
                   ^
 ffff88809e79f880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88809e79f900: fb fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc
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