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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 ffff888013d57800 by task systemd-udevd/6378

CPU: 0 PID: 6378 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:preempt_count arch/x86/include/asm/preempt.h:27 [inline]
RIP: 0010:check_kcov_mode kernel/kcov.c:163 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:197
Code: f0 4d 89 03 e9 f2 fc ff ff b9 ff ff ff ff ba 08 00 00 00 4d 8b 03 48 0f bd ca 49 8b 45 00 48 63 c9 e9 64 ff ff ff 0f 1f 40 00 <65> 8b 05 59 f9 8d 7e 89 c1 48 8b 34 24 81 e1 00 01 00 00 65 48 8b
RSP: 0018:ffffc9000374f910 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000007
RDX: 0000000000000000 RSI: ffff8880191c9c40 RDI: 0000000000000003
RBP: ffff88801c1bbf80 R08: ffffffff89bb3520 R09: ffffffff83935339
R10: 0000000000000007 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000280 R14: dffffc0000000000 R15: 0000000000000000
 tomoyo_domain_quota_is_ok+0x426/0x550 security/tomoyo/util.c:1068
 tomoyo_supervisor+0x2f2/0xf00 security/tomoyo/common.c:2089
 tomoyo_audit_path_number_log security/tomoyo/file.c:235 [inline]
 tomoyo_path_number_perm+0x419/0x590 security/tomoyo/file.c:734
 security_path_chmod+0xe0/0x150 security/security.c:1161
 chmod_common+0x156/0x440 fs/open.c:580
 vfs_fchmod fs/open.c:601 [inline]
 __do_sys_fchmod fs/open.c:610 [inline]
 __se_sys_fchmod fs/open.c:604 [inline]
 __x64_sys_fchmod+0x10e/0x190 fs/open.c:604
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fc84c02e5c7
Code: 73 01 c3 48 8b 0d d1 d8 2b 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 5b 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d a1 d8 2b 00 f7 d8 64 89 01 48
RSP: 002b:00007ffd123045d8 EFLAGS: 00000206 ORIG_RAX: 000000000000005b
RAX: ffffffffffffffda RBX: 0000564232a996b0 RCX: 00007fc84c02e5c7
RDX: 0000000000000000 RSI: 00000000000001a4 RDI: 000000000000000f
RBP: 00007ffd123046a0 R08: 0000564232a86110 R09: 0000000000000230
R10: 0000000000000000 R11: 0000000000000206 R12: 00007ffd123045e0
R13: 0000000000000001 R14: 0000000000000000 R15: 000000000000000e

The buggy address belongs to the page:
page:ffffea00004f55c0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x13d57
flags: 0xfff00000000000()
raw: 00fff00000000000 0000000000000000 ffffea00004f55c8 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888013d57700: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888013d57780: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff888013d57800: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff888013d57880: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888013d57900: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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