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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: 13203 Comm: syz-executor.3 Not tainted 5.16.0-rc5-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: 0033:0x7f27c8e47e99
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:00007f27c77bd168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f27c8f5af60 RCX: 00007f27c8e47e99
RDX: 00000000200000c0 RSI: 00000000400454ca RDI: 0000000000000005
RBP: 00007f27c8ea1ff1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffd88243d8f R14: 00007f27c77bd300 R15: 0000000000022000
 </TASK>

Allocated by task 13203:
 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:5594
 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 13203:
 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 ffff88801dc81340
 which belongs to the cache kmalloc-32 of size 32
The buggy address is located 0 bytes inside of
 32-byte region [ffff88801dc81340, ffff88801dc81360)
The buggy address belongs to the page:
page:ffffea0000772040 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88801dc81fc1 pfn:0x1dc81
flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000200 ffffea0000516348 ffffea0001d095c8 ffff888010c40100
raw: ffff88801dc81fc1 ffff88801dc81000 000000010000003c 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 0x2420c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_COMP|__GFP_THISNODE), pid 982, ts 8897237803, free_ts 8869961224
 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]
 __do_kmalloc mm/slab.c:3700 [inline]
 __kmalloc+0x3b3/0x4d0 mm/slab.c:3711
 kmalloc include/linux/slab.h:595 [inline]
 kzalloc include/linux/slab.h:724 [inline]
 lsm_task_alloc security/security.c:614 [inline]
 security_task_alloc+0x10b/0x250 security/security.c:1644
 copy_process+0x2132/0x75a0 kernel/fork.c:2173
 kernel_clone+0xe7/0xab0 kernel/fork.c:2582
 kernel_thread+0xb5/0xf0 kernel/fork.c:2634
 call_usermodehelper_exec_work kernel/umh.c:174 [inline]
 call_usermodehelper_exec_work+0xcc/0x180 kernel/umh.c:160
 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_list+0x1a9/0xfa0 mm/page_alloc.c:3425
 release_pages+0x3f4/0x1480 mm/swap.c:980
 tlb_batch_pages_flush mm/mmu_gather.c:49 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:242 [inline]
 tlb_flush_mmu mm/mmu_gather.c:249 [inline]
 tlb_finish_mmu+0x165/0x8c0 mm/mmu_gather.c:340
 exit_mmap+0x1ea/0x630 mm/mmap.c:3172
 __mmput+0x122/0x4b0 kernel/fork.c:1113
 mmput+0x56/0x60 kernel/fork.c:1134
 free_bprm+0x65/0x2e0 fs/exec.c:1481
 kernel_execve+0x380/0x460 fs/exec.c:1978
 call_usermodehelper_exec_async+0x2e3/0x580 kernel/umh.c:112
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Memory state around the buggy address:
 ffff88801dc81200: 00 00 00 fc fc fc fc fc fa fb fb fb fc fc fc fc
 ffff88801dc81280: 00 00 01 fc fc fc fc fc 00 00 00 00 fc fc fc fc
>ffff88801dc81300: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
                                           ^
 ffff88801dc81380: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
 ffff88801dc81400: 00 00 01 fc fc fc fc fc fa fb fb fb fc fc fc fc
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