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audit: type=1400 audit(1537821747.371:8): avc:  denied  { prog_load } for  pid=1792 comm="syz-executor352" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=bpf permissive=1
audit: type=1400 audit(1537821747.391:9): avc:  denied  { prog_run } for  pid=1792 comm="syz-executor352" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=bpf permissive=1
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BUG: KASAN: use-after-free in _copy_to_user+0x9a/0xc0 lib/usercopy.c:27
Read of size 660 at addr ffff8801c3e3fffa by task syz-executor352/1792

CPU: 0 PID: 1792 Comm: syz-executor352 Not tainted 4.14.71+ #8
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0xb9/0x11b lib/dump_stack.c:53
 print_address_description+0x60/0x22b mm/kasan/report.c:252
 kasan_report_error mm/kasan/report.c:351 [inline]
 kasan_report.cold.6+0x11b/0x2dd mm/kasan/report.c:409
 _copy_to_user+0x9a/0xc0 lib/usercopy.c:27
 copy_to_user include/linux/uaccess.h:155 [inline]
 bpf_test_finish.isra.0+0xc8/0x190 net/bpf/test_run.c:59
 bpf_prog_test_run_skb+0x4d0/0x8c0 net/bpf/test_run.c:144
 bpf_prog_test_run kernel/bpf/syscall.c:1330 [inline]
 SYSC_bpf kernel/bpf/syscall.c:1602 [inline]
 SyS_bpf+0x79d/0x3640 kernel/bpf/syscall.c:1547
 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x440259
RSP: 002b:00007fff63f9d828 EFLAGS: 00000213 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440259
RDX: 0000000000000028 RSI: 0000000020000280 RDI: 000000000000000a
RBP: 00000000006ca018 R08: 0000000000000000 R09: 00000000004002c8
R10: 0000000000000000 R11: 0000000000000213 R12: 0000000000401ae0
R13: 0000000000401b70 R14: 0000000000000000 R15: 0000000000000000

The buggy address belongs to the page:
page:ffffea00070f8fc0 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0x4000000000000000()
raw: 4000000000000000 0000000000000000 0000000000000000 00000000ffffffff
raw: 0000000000000000 ffffea00070f8fe0 0000000000000000 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801c3e3fe80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8801c3e3ff00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff8801c3e3ff80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                                                ^
 ffff8801c3e40000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8801c3e40080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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