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BUG: KASAN: slab-out-of-bounds in memcpy include/linux/fortify-string.h:191 [inline]
BUG: KASAN: slab-out-of-bounds in page_to_skb+0x5cf/0xb70 drivers/net/virtio_net.c:480
Read of size 12 at addr ffff88802b1df800 by task systemd-udevd/6410

CPU: 1 PID: 6410 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:check_kcov_mode kernel/kcov.c:163 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0xd/0x60 kernel/kcov.c:197
Code: 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 14 25 00 f0 01 00 a9 00 01 ff 00 74 0e
RSP: 0018:ffffc900038af5a8 EFLAGS: 00000297
RAX: 0000000080000000 RBX: 0000000000000000 RCX: 0000000080000000
RDX: 0000000000000000 RSI: ffffffff8393556c RDI: 0000000000000003
RBP: ffff888020b1a000 R08: ffffffff89bb3520 R09: ffffffff83935339
R10: 0000000000000007 R11: 0000000000000001 R12: 0000000000000001
R13: 000000000000014d R14: dffffc0000000000 R15: 0000000000000000
 tomoyo_domain_quota_is_ok+0x3fc/0x550 security/tomoyo/util.c:1071
 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_check_open_permission+0x33e/0x380 security/tomoyo/file.c:777
 tomoyo_file_open security/tomoyo/tomoyo.c:313 [inline]
 tomoyo_file_open+0xa3/0xd0 security/tomoyo/tomoyo.c:308
 security_file_open+0x52/0x4f0 security/security.c:1589
 do_dentry_open+0x358/0x11b0 fs/open.c:813
 do_open fs/namei.c:3367 [inline]
 path_openat+0x1c0e/0x27e0 fs/namei.c:3500
 do_filp_open+0x190/0x3d0 fs/namei.c:3527
 do_sys_openat2+0x16d/0x420 fs/open.c:1187
 do_sys_open fs/open.c:1203 [inline]
 __do_sys_open fs/open.c:1211 [inline]
 __se_sys_open fs/open.c:1207 [inline]
 __x64_sys_open+0x119/0x1c0 fs/open.c:1207
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fe51ccb66f0
Code: 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 83 3d 19 30 2c 00 00 75 10 b8 02 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 fe 9d 01 00 48 89 04 24
RSP: 002b:00007ffd37e54a28 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fe51ccb66f0
RDX: 0000000000000180 RSI: 00000000000800c2 RDI: 00005596e650bea0
RBP: 000000000003a2f8 R08: 000000000000fefe R09: 0000000000000030
R10: 0000000000000000 R11: 0000000000000246 R12: 00005596e650beb7
R13: 8421084210842109 R14: 00000000000800c2 R15: 00007fe51cd44540

Allocated by task 6417:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:427 [inline]
 ____kasan_kmalloc mm/kasan/common.c:506 [inline]
 ____kasan_kmalloc mm/kasan/common.c:465 [inline]
 __kasan_kmalloc+0x99/0xc0 mm/kasan/common.c:515
 kmalloc include/linux/slab.h:559 [inline]
 tomoyo_realpath_from_path+0xc3/0x620 security/tomoyo/realpath.c:254
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_path_number_perm+0x1d5/0x590 security/tomoyo/file.c:723
 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

Freed by task 6417:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
 kasan_set_track+0x1c/0x30 mm/kasan/common.c:46
 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:357
 ____kasan_slab_free mm/kasan/common.c:360 [inline]
 ____kasan_slab_free mm/kasan/common.c:325 [inline]
 __kasan_slab_free+0xf5/0x130 mm/kasan/common.c:367
 kasan_slab_free include/linux/kasan.h:199 [inline]
 slab_free_hook mm/slub.c:1562 [inline]
 slab_free_freelist_hook+0x92/0x210 mm/slub.c:1600
 slab_free mm/slub.c:3161 [inline]
 kfree+0xe5/0x7f0 mm/slub.c:4213
 tomoyo_realpath_from_path+0x191/0x620 security/tomoyo/realpath.c:291
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_path_number_perm+0x1d5/0x590 security/tomoyo/file.c:723
 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

The buggy address belongs to the object at ffff88802b1de000
 which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 2048 bytes to the right of
 4096-byte region [ffff88802b1de000, ffff88802b1df000)
The buggy address belongs to the page:
page:ffffea0000ac7600 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2b1d8
head:ffffea0000ac7600 order:3 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head)
raw: 00fff00000010200 dead000000000100 dead000000000122 ffff888010842140
raw: 0000000000000000 0000000000040004 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88802b1df700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88802b1df780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88802b1df800: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                   ^
 ffff88802b1df880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88802b1df900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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