==================================================================
BUG: KASAN: use-after-free in memcpy include/linux/fortify-string.h:191 [inline]
BUG: KASAN: use-after-free in page_to_skb+0x5cf/0xb70 drivers/net/virtio_net.c:480
Read of size 12 at addr ffff88802b43f800 by task systemd-udevd/6362

CPU: 1 PID: 6362 Comm: systemd-udevd Not tainted 5.12.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x141/0x1d7 lib/dump_stack.c:120
 print_address_description.constprop.0.cold+0x5b/0x2f8 mm/kasan/report.c:232
 __kasan_report mm/kasan/report.c:399 [inline]
 kasan_report.cold+0x7c/0xd8 mm/kasan/report.c:416
 check_region_inline mm/kasan/generic.c:180 [inline]
 kasan_check_range+0x13d/0x180 mm/kasan/generic.c:186
 memcpy+0x20/0x60 mm/kasan/shadow.c:65
 memcpy include/linux/fortify-string.h:191 [inline]
 page_to_skb+0x5cf/0xb70 drivers/net/virtio_net.c:480
 receive_mergeable drivers/net/virtio_net.c:1009 [inline]
 receive_buf+0x2b82/0x6220 drivers/net/virtio_net.c:1119
 virtnet_receive drivers/net/virtio_net.c:1411 [inline]
 virtnet_poll+0x568/0x10b0 drivers/net/virtio_net.c:1516
 __napi_poll+0xaf/0x440 net/core/dev.c:6962
 napi_poll net/core/dev.c:7029 [inline]
 net_rx_action+0x801/0xb40 net/core/dev.c:7116
 __do_softirq+0x29b/0x9f6 kernel/softirq.c:345
 invoke_softirq kernel/softirq.c:221 [inline]
 __irq_exit_rcu kernel/softirq.c:422 [inline]
 irq_exit_rcu+0x134/0x200 kernel/softirq.c:434
 common_interrupt+0xa4/0xd0 arch/x86/kernel/irq.c:240
 </IRQ>
 asm_common_interrupt+0x1e/0x40 arch/x86/include/asm/idtentry.h:623
RIP: 0010:tomoyo_domain_quota_is_ok+0x315/0x550 security/tomoyo/util.c:1092
Code: db e8 ff a1 e0 fd 89 d9 44 89 e0 31 ff d3 f8 83 e0 01 41 89 c7 89 c6 e8 99 a9 e0 fd 45 85 ff 74 09 e8 df a1 e0 fd 41 83 c5 01 <e8> d6 a1 e0 fd 8d 73 01 bf 10 00 00 00 83 c3 01 e8 76 a8 e0 fd 83
RSP: 0018:ffffc9000396f920 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff88801bfb8000 RDI: 0000000000000003
RBP: ffff888013c97d80 R08: 0000000000000000 R09: ffffffff83935339
R10: ffffffff83935477 R11: 0000000000000002 R12: 0000000000000020
R13: 0000000000000208 R14: dffffc0000000000 R15: 0000000000000000
 tomoyo_supervisor+0x2f2/0xf00 security/tomoyo/common.c:2089
 tomoyo_audit_path_log security/tomoyo/file.c:168 [inline]
 tomoyo_path_permission security/tomoyo/file.c:587 [inline]
 tomoyo_path_permission+0x270/0x3a0 security/tomoyo/file.c:573
 tomoyo_path_perm+0x39e/0x400 security/tomoyo/file.c:838
 tomoyo_path_symlink+0x94/0xe0 security/tomoyo/tomoyo.c:200
 security_path_symlink+0xdf/0x150 security/security.c:1119
 do_symlinkat+0x123/0x300 fs/namei.c:4203
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f3f2a549027
Code: f0 ff ff 73 01 c3 48 8b 0d 6e be 2b 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 b8 58 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 41 be 2b 00 f7 d8 64 89 01 48
RSP: 002b:00007fffd09ed358 EFLAGS: 00000202 ORIG_RAX: 0000000000000058
RAX: ffffffffffffffda RBX: 00007fffd09eddf0 RCX: 00007f3f2a549027
RDX: 0000000000000000 RSI: 00007fffd09eddf0 RDI: 00007fffd09ed410
RBP: 00000000ffffffff R08: 000000000000fcff R09: 000000000000000f
R10: 00007fffd09eddc0 R11: 0000000000000202 R12: 00007fffd09ed410
R13: 000055f38fbf0940 R14: 000055f38ec081d0 R15: 00007fffd09ede00

The buggy address belongs to the page:
page:ffffea0000ad0fc0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2b43f
flags: 0xfff00000000000()
raw: 00fff00000000000 0000000000000000 ffffea0000ad0fc8 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88802b43f700: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88802b43f780: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88802b43f800: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff88802b43f880: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88802b43f900: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================