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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 ffff88802b5bf800 by task systemd-udevd/6422

CPU: 1 PID: 6422 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_check_acl+0xc1/0x450 security/tomoyo/domain.c:173
Code: f5 28 e2 fd 48 8d 7b 18 48 89 f8 48 89 fa 48 c1 e8 03 83 e2 07 0f b6 04 28 38 d0 7f 08 84 c0 0f 85 f7 02 00 00 44 0f b6 73 18 <31> ff 44 89 f6 e8 75 2f e2 fd 45 84 f6 0f 85 61 01 00 00 e8 b7 28
RSP: 0018:ffffc900058cf5a0 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff888144ae0000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8391cd6b RDI: ffff888144ae0018
RBP: dffffc0000000000 R08: 0000000000000000 R09: 0000000000000002
R10: ffffffff8391cdf1 R11: 0000000000000000 R12: ffffc900058cf668
R13: ffff888015623d10 R14: 0000000000000000 R15: 0000000000000002
 tomoyo_path_number_perm+0x32a/0x590 security/tomoyo/file.c:733
 tomoyo_path_mknod+0x10d/0x190 security/tomoyo/tomoyo.c:240
 security_path_mknod+0xf9/0x170 security/security.c:1087
 may_o_create fs/namei.c:3040 [inline]
 lookup_open.isra.0+0x475/0x13d0 fs/namei.c:3184
 open_last_lookups fs/namei.c:3291 [inline]
 path_openat+0x9b4/0x27e0 fs/namei.c:3497
 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: 0033:0x7f0600a926f0
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:00007ffd2af724c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f0600a926f0
RDX: 0000000000000180 RSI: 00000000000800c2 RDI: 000055c872390620
RBP: 000000000003a2f8 R08: 000000000000fefe R09: 0000000000000030
R10: 0000000000000000 R11: 0000000000000246 R12: 000055c872390635
R13: 8421084210842109 R14: 00000000000800c2 R15: 00007f0600b20540

Allocated by task 1:
 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_perm+0x21b/0x400 security/tomoyo/file.c:822
 security_inode_getattr+0xcf/0x140 security/security.c:1288
 vfs_getattr fs/stat.c:131 [inline]
 vfs_fstat+0x43/0xb0 fs/stat.c:156
 __do_sys_newfstat+0x81/0x100 fs/stat.c:396
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Freed by task 1:
 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_perm+0x21b/0x400 security/tomoyo/file.c:822
 security_inode_getattr+0xcf/0x140 security/security.c:1288
 vfs_getattr fs/stat.c:131 [inline]
 vfs_fstat+0x43/0xb0 fs/stat.c:156
 __do_sys_newfstat+0x81/0x100 fs/stat.c:396
 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 ffff88802b5be000
 which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 2048 bytes to the right of
 4096-byte region [ffff88802b5be000, ffff88802b5bf000)
The buggy address belongs to the page:
page:ffffea0000ad6e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2b5b8
head:ffffea0000ad6e00 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:
 ffff88802b5bf700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88802b5bf780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88802b5bf800: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                   ^
 ffff88802b5bf880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88802b5bf900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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