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BUG: KASAN: double-free or invalid-free in security_tun_dev_free_security+0x3e/0x70 security/security.c:2342

CPU: 0 PID: 12504 Comm: syz-executor.3 Not tainted 5.16.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 print_address_description.constprop.0.cold+0x8d/0x2ed mm/kasan/report.c:247
 kasan_report_invalid_free+0x51/0x80 mm/kasan/report.c:372
 ____kasan_slab_free mm/kasan/common.c:346 [inline]
 __kasan_slab_free+0xf6/0x110 mm/kasan/common.c:374
 kasan_slab_free include/linux/kasan.h:235 [inline]
 __cache_free mm/slab.c:3445 [inline]
 kfree+0x10d/0x2c0 mm/slab.c:3802
 security_tun_dev_free_security+0x3e/0x70 security/security.c:2342
 tun_free_netdev+0xdc/0x140 drivers/net/tun.c:2215
 netdev_run_todo+0x6b4/0xa80 net/core/dev.c:10630
 __tun_chr_ioctl.isra.0+0x9a1/0x4230 drivers/net/tun.c:3302
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl fs/ioctl.c:860 [inline]
 __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fa56a38fe99
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fa568d05168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fa56a4a2f60 RCX: 00007fa56a38fe99
RDX: 00000000200000c0 RSI: 00000000400454ca RDI: 0000000000000005
RBP: 00007fa56a3e9ff1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe2e56125f R14: 00007fa568d05300 R15: 0000000000022000
 </TASK>

Allocated by task 12504:
 kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 ____kasan_kmalloc mm/kasan/common.c:513 [inline]
 ____kasan_kmalloc mm/kasan/common.c:472 [inline]
 __kasan_kmalloc+0xa6/0xd0 mm/kasan/common.c:522
 kasan_kmalloc include/linux/kasan.h:269 [inline]
 kmem_cache_alloc_trace+0x1ea/0x4a0 mm/slab.c:3575
 kmalloc include/linux/slab.h:590 [inline]
 kzalloc include/linux/slab.h:724 [inline]
 selinux_tun_dev_alloc_security+0x43/0x180 security/selinux/hooks.c:5599
 security_tun_dev_alloc_security+0x40/0x90 security/security.c:2336
 __tun_chr_ioctl.isra.0+0x27e6/0x4230 drivers/net/tun.c:2727
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl fs/ioctl.c:860 [inline]
 __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Freed by task 12504:
 kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38
 kasan_set_track+0x21/0x30 mm/kasan/common.c:46
 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370
 ____kasan_slab_free mm/kasan/common.c:366 [inline]
 ____kasan_slab_free mm/kasan/common.c:328 [inline]
 __kasan_slab_free+0xd1/0x110 mm/kasan/common.c:374
 kasan_slab_free include/linux/kasan.h:235 [inline]
 __cache_free mm/slab.c:3445 [inline]
 kfree+0x10d/0x2c0 mm/slab.c:3802
 security_tun_dev_free_security+0x3e/0x70 security/security.c:2342
 __tun_chr_ioctl.isra.0+0x2cbf/0x4230 drivers/net/tun.c:2782
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl fs/ioctl.c:860 [inline]
 __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

The buggy address belongs to the object at ffff888074bef300
 which belongs to the cache kmalloc-32 of size 32
The buggy address is located 0 bytes inside of
 32-byte region [ffff888074bef300, ffff888074bef320)
The buggy address belongs to the page:
page:ffffea0001d2fbc0 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888074beffc1 pfn:0x74bef
flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000200 ffffea00005ec408 ffffea0000831cc8 ffff888010c40100
raw: ffff888074beffc1 ffff888074bef000 000000010000003f 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x3420c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_COMP|__GFP_HARDWALL|__GFP_THISNODE), pid 3664, ts 63831597269, free_ts 33489047708
 prep_new_page mm/page_alloc.c:2418 [inline]
 get_page_from_freelist+0xa72/0x2f50 mm/page_alloc.c:4149
 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5369
 __alloc_pages_node include/linux/gfp.h:570 [inline]
 kmem_getpages mm/slab.c:1377 [inline]
 cache_grow_begin+0x75/0x470 mm/slab.c:2593
 cache_alloc_refill+0x27f/0x380 mm/slab.c:2965
 ____cache_alloc mm/slab.c:3048 [inline]
 ____cache_alloc mm/slab.c:3031 [inline]
 __do_cache_alloc mm/slab.c:3275 [inline]
 slab_alloc mm/slab.c:3316 [inline]
 kmem_cache_alloc_trace+0x380/0x4a0 mm/slab.c:3573
 kmalloc include/linux/slab.h:590 [inline]
 kzalloc include/linux/slab.h:724 [inline]
 nsim_fib6_rt_nh_add+0x4a/0x290 drivers/net/netdevsim/fib.c:497
 nsim_fib6_rt_create drivers/net/netdevsim/fib.c:559 [inline]
 nsim_fib6_rt_insert drivers/net/netdevsim/fib.c:749 [inline]
 nsim_fib6_event drivers/net/netdevsim/fib.c:853 [inline]
 nsim_fib_event drivers/net/netdevsim/fib.c:886 [inline]
 nsim_fib_event_work+0x134f/0x2490 drivers/net/netdevsim/fib.c:1477
 process_one_work+0x9b2/0x1690 kernel/workqueue.c:2298
 worker_thread+0x658/0x11f0 kernel/workqueue.c:2445
 kthread+0x405/0x4f0 kernel/kthread.c:327
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1338 [inline]
 free_pcp_prepare+0x374/0x870 mm/page_alloc.c:1389
 free_unref_page_prepare mm/page_alloc.c:3309 [inline]
 free_unref_page+0x19/0x690 mm/page_alloc.c:3388
 slab_destroy mm/slab.c:1627 [inline]
 slabs_destroy+0x89/0xc0 mm/slab.c:1647
 cache_flusharray mm/slab.c:3418 [inline]
 ___cache_free+0x4cc/0x610 mm/slab.c:3480
 qlink_free mm/kasan/quarantine.c:146 [inline]
 qlist_free_all+0x4e/0x110 mm/kasan/quarantine.c:165
 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:272
 __kasan_slab_alloc+0x97/0xb0 mm/kasan/common.c:444
 kasan_slab_alloc include/linux/kasan.h:259 [inline]
 slab_post_alloc_hook mm/slab.h:519 [inline]
 slab_alloc_node mm/slab.c:3261 [inline]
 kmem_cache_alloc_node+0x2ea/0x590 mm/slab.c:3599
 __alloc_skb+0x215/0x340 net/core/skbuff.c:414
 alloc_skb include/linux/skbuff.h:1126 [inline]
 netlink_alloc_large_skb net/netlink/af_netlink.c:1191 [inline]
 netlink_sendmsg+0x98f/0xdf0 net/netlink/af_netlink.c:1896
 sock_sendmsg_nosec net/socket.c:704 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:724
 __sys_sendto+0x21c/0x320 net/socket.c:2036
 __do_sys_sendto net/socket.c:2048 [inline]
 __se_sys_sendto net/socket.c:2044 [inline]
 __x64_sys_sendto+0xdd/0x1b0 net/socket.c:2044
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Memory state around the buggy address:
 ffff888074bef200: fa fb fb fb fc fc fc fc 00 00 00 00 fc fc fc fc
 ffff888074bef280: fa fb fb fb fc fc fc fc 00 00 04 fc fc fc fc fc
>ffff888074bef300: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
                   ^
 ffff888074bef380: fa fb fb fb fc fc fc fc 00 00 00 00 fc fc fc fc
 ffff888074bef400: 00 fc fc fc fc fc fc fc 00 fc fc fc fc fc fc fc
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