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BUG: KASAN: use-after-free in __write_once_size include/linux/compiler.h:221 [inline]
BUG: KASAN: use-after-free in __hlist_del include/linux/list.h:748 [inline]
BUG: KASAN: use-after-free in hlist_del_rcu include/linux/rculist.h:455 [inline]
BUG: KASAN: use-after-free in __xfrm_policy_unlink+0x4b1/0x5c0 net/xfrm/xfrm_policy.c:2217
Write of size 8 at addr ffff88808f212b00 by task kworker/u4:7/15953

CPU: 0 PID: 15953 Comm: kworker/u4:7 Not tainted 5.2.0-rc5+ #43
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: netns cleanup_net
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:188
 __kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317
 kasan_report+0x12/0x20 mm/kasan/common.c:614
 __asan_report_store8_noabort+0x17/0x20 mm/kasan/generic_report.c:137
 __write_once_size include/linux/compiler.h:221 [inline]
 __hlist_del include/linux/list.h:748 [inline]
 hlist_del_rcu include/linux/rculist.h:455 [inline]
 __xfrm_policy_unlink+0x4b1/0x5c0 net/xfrm/xfrm_policy.c:2217
 xfrm_policy_flush+0x331/0x460 net/xfrm/xfrm_policy.c:1794
 xfrm_policy_fini+0x49/0x3a0 net/xfrm/xfrm_policy.c:4080
 xfrm_net_exit+0x1d/0x70 net/xfrm/xfrm_policy.c:4142
 ops_exit_list.isra.0+0xaa/0x150 net/core/net_namespace.c:165
 cleanup_net+0x4e2/0xa40 net/core/net_namespace.c:575
 process_one_work+0x989/0x1790 kernel/workqueue.c:2269
 worker_thread+0x98/0xe40 kernel/workqueue.c:2415
 kthread+0x354/0x420 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352

Allocated by task 28083:
 save_stack+0x23/0x90 mm/kasan/common.c:71
 set_track mm/kasan/common.c:79 [inline]
 __kasan_kmalloc mm/kasan/common.c:489 [inline]
 __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:462
 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:503
 __do_kmalloc mm/slab.c:3660 [inline]
 __kmalloc+0x15c/0x740 mm/slab.c:3669
 kmalloc include/linux/slab.h:552 [inline]
 kzalloc include/linux/slab.h:742 [inline]
 tomoyo_encode2.part.0+0xf5/0x400 security/tomoyo/realpath.c:44
 tomoyo_encode2 security/tomoyo/realpath.c:30 [inline]
 tomoyo_encode+0x2b/0x50 security/tomoyo/realpath.c:79
 tomoyo_realpath_from_path+0x1d3/0x7a0 security/tomoyo/realpath.c:316
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_path_perm+0x230/0x430 security/tomoyo/file.c:822
 tomoyo_inode_getattr+0x1d/0x30 security/tomoyo/tomoyo.c:129
 security_inode_getattr+0xf2/0x150 security/security.c:1179
 vfs_getattr+0x25/0x70 fs/stat.c:115
 vfs_statx_fd+0x71/0xc0 fs/stat.c:145
 vfs_fstat include/linux/fs.h:3209 [inline]
 __do_sys_newfstat+0x9b/0x120 fs/stat.c:378
 __se_sys_newfstat fs/stat.c:375 [inline]
 __x64_sys_newfstat+0x54/0x80 fs/stat.c:375
 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 28083:
 save_stack+0x23/0x90 mm/kasan/common.c:71
 set_track mm/kasan/common.c:79 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/common.c:451
 kasan_slab_free+0xe/0x10 mm/kasan/common.c:459
 __cache_free mm/slab.c:3432 [inline]
 kfree+0xcf/0x220 mm/slab.c:3755
 tomoyo_path_perm+0x24e/0x430 security/tomoyo/file.c:842
 tomoyo_inode_getattr+0x1d/0x30 security/tomoyo/tomoyo.c:129
 security_inode_getattr+0xf2/0x150 security/security.c:1179
 vfs_getattr+0x25/0x70 fs/stat.c:115
 vfs_statx_fd+0x71/0xc0 fs/stat.c:145
 vfs_fstat include/linux/fs.h:3209 [inline]
 __do_sys_newfstat+0x9b/0x120 fs/stat.c:378
 __se_sys_newfstat fs/stat.c:375 [inline]
 __x64_sys_newfstat+0x54/0x80 fs/stat.c:375
 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff88808f212b00
 which belongs to the cache kmalloc-64 of size 64
The buggy address is located 0 bytes inside of
 64-byte region [ffff88808f212b00, ffff88808f212b40)
The buggy address belongs to the page:
page:ffffea00023c8480 refcount:1 mapcount:0 mapping:ffff8880aa400340 index:0x0
flags: 0x1fffc0000000200(slab)
raw: 01fffc0000000200 ffffea0002765488 ffffea00029d1a08 ffff8880aa400340
raw: 0000000000000000 ffff88808f212000 0000000100000020 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88808f212a00: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
 ffff88808f212a80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
>ffff88808f212b00: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
                   ^
 ffff88808f212b80: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
 ffff88808f212c00: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
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