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BUG: KASAN: double-free or invalid-free in security_tun_dev_free_security+0x3e/0x70 security/security.c:2276

CPU: 1 PID: 22346 Comm: syz-executor.1 Not tainted 5.11.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x107/0x163 lib/dump_stack.c:120
 print_address_description.constprop.0.cold+0x5b/0x2c6 mm/kasan/report.c:230
 kasan_report_invalid_free+0x51/0x80 mm/kasan/report.c:355
 ____kasan_slab_free+0xcc/0xe0 mm/kasan/common.c:341
 kasan_slab_free include/linux/kasan.h:192 [inline]
 __cache_free mm/slab.c:3424 [inline]
 kfree+0xed/0x270 mm/slab.c:3760
 security_tun_dev_free_security+0x3e/0x70 security/security.c:2276
 tun_free_netdev+0xdc/0x140 drivers/net/tun.c:2205
 netdev_run_todo+0x8c3/0xdd0 net/core/dev.c:10344
 __tun_chr_ioctl.isra.0+0xb2c/0x4360 drivers/net/tun.c:3254
 vfs_ioctl fs/ioctl.c:48 [inline]
 __do_sys_ioctl fs/ioctl.c:753 [inline]
 __se_sys_ioctl fs/ioctl.c:739 [inline]
 __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:739
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45e219
Code: 0d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 db b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fd108238c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045e219
RDX: 00000000200000c0 RSI: 00000000400454ca RDI: 0000000000000003
RBP: 000000000119c068 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119c034
R13: 00007fff3458936f R14: 00007fd1082399c0 R15: 000000000119c034

Allocated by task 22346:
 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:401 [inline]
 ____kasan_kmalloc.constprop.0+0x7f/0xa0 mm/kasan/common.c:429
 kasan_kmalloc include/linux/kasan.h:219 [inline]
 kmem_cache_alloc_trace+0x1e0/0x400 mm/slab.c:3554
 kmalloc include/linux/slab.h:552 [inline]
 kzalloc include/linux/slab.h:682 [inline]
 selinux_tun_dev_alloc_security+0x43/0x190 security/selinux/hooks.c:5449
 security_tun_dev_alloc_security+0x40/0x90 security/security.c:2270
 __tun_chr_ioctl.isra.0+0x2858/0x4360 drivers/net/tun.c:2717
 vfs_ioctl fs/ioctl.c:48 [inline]
 __do_sys_ioctl fs/ioctl.c:753 [inline]
 __se_sys_ioctl fs/ioctl.c:739 [inline]
 __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:739
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Freed by task 22346:
 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:356
 ____kasan_slab_free+0xb0/0xe0 mm/kasan/common.c:362
 kasan_slab_free include/linux/kasan.h:192 [inline]
 __cache_free mm/slab.c:3424 [inline]
 kfree+0xed/0x270 mm/slab.c:3760
 security_tun_dev_free_security+0x3e/0x70 security/security.c:2276
 __tun_chr_ioctl.isra.0+0x2db0/0x4360 drivers/net/tun.c:2772
 vfs_ioctl fs/ioctl.c:48 [inline]
 __do_sys_ioctl fs/ioctl.c:753 [inline]
 __se_sys_ioctl fs/ioctl.c:739 [inline]
 __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:739
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

The buggy address belongs to the object at ffff888015412040
 which belongs to the cache kmalloc-32 of size 32
The buggy address is located 0 bytes inside of
 32-byte region [ffff888015412040, ffff888015412060)
The buggy address belongs to the page:
page:00000000dc3c5bc4 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888015412fc1 pfn:0x15412
flags: 0xfff00000000200(slab)
raw: 00fff00000000200 ffffea000089f788 ffffea0000948848 ffff888010040100
raw: ffff888015412fc1 ffff888015412000 000000010000002d 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888015411f00: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc
 ffff888015411f80: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
>ffff888015412000: fa fb fb fb fc fc fc fc fa fb fb fb fc fc fc fc
                                           ^
 ffff888015412080: 00 00 01 fc fc fc fc fc 00 00 01 fc fc fc fc fc
 ffff888015412100: 00 00 01 fc fc fc fc fc fa fb fb fb fc fc fc fc
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