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kernel BUG at mm/slab.c:4421!
BUG: KASAN: use-after-free in _copy_to_user+0xe9/0x110 lib/usercopy.c:27
invalid opcode: 0000 [#1] SMP KASAN
Read of size 1024 at addr ffff8801913ffffc by task syz-executor0/10295

CPU: 1 PID: 10223 Comm: syz-executor0 Not tainted 4.18.0-rc3+ #58
CPU: 0 PID: 10295 Comm: syz-executor0 Not tainted 4.18.0-rc3+ #58
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
RIP: 0010:__check_heap_object+0xa7/0xb5 mm/slab.c:4446
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1c9/0x2b4 lib/dump_stack.c:113
Code: 
48 
c7 
c7 e0 
8b 
 print_address_description+0x6c/0x20b mm/kasan/report.c:256
c0 
88 
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412
e8 
 check_memory_region_inline mm/kasan/kasan.c:260 [inline]
 check_memory_region+0x13e/0x1b0 mm/kasan/kasan.c:267
87 
 kasan_check_read+0x11/0x20 mm/kasan/kasan.c:272
7a 
 _copy_to_user+0xe9/0x110 lib/usercopy.c:27
08 
 copy_to_user include/linux/uaccess.h:155 [inline]
 bpf_test_finish.isra.7+0xee/0x1f0 net/bpf/test_run.c:59
00 
5d 
c3 
 bpf_prog_test_run_skb+0x7d7/0xa30 net/bpf/test_run.c:144
41 
8b 
91 
04 
01 
00 
 bpf_prog_test_run+0x130/0x1a0 kernel/bpf/syscall.c:1686
00 
 __do_sys_bpf kernel/bpf/syscall.c:2323 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:2267 [inline]
 __x64_sys_bpf+0x3d8/0x510 kernel/bpf/syscall.c:2267
48 29 
c7 
48 39 
d7 
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
77 
be 
48 
01 
d0 
48 
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
29 c8 
RIP: 0033:0x455ab9
48 
Code: 
39 
1d 
f0 
ba 
72 
fb 
b3 
ff 
5d 
c3 
c3 
66 
<0f> 
2e 
0b 
0f 1f 
48 c7 
84 
c7 
00 00 
e0 
00 
8b 
00 
c0 
00 
88 
66 
e8 
90 48 
6d 
89 
81 
f8 
08 
48 
00 
89 
44 
f7 
89 
48 
e1 
89 
4c 
d6 
8d 
48 
45 
89 
c4 
ca 
48 
4d 
89 
RSP: 0018:ffff88019a6dfa10 EFLAGS: 00010246
c2 
4d 
RAX: 0000000000000001 RBX: 1ffff100334dbf49 RCX: 0000000000000015
89 
RDX: ffff88019d400080 RSI: 0000000000000400 RDI: ffff88019d7ffffc
c8 4c 
RBP: ffff88019a6dfa10 R08: ffff8801ae256040 R09: ffff8801da802c80
8b 
R10: 00000000003fdf84 R11: 0000000000000001 R12: ffff88019d7ffffc
4c 
R13: 0000000000000400 R14: 0000000000000001 R15: ffffea0006750000
24 
FS:  00007fd899e46700(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000
08 0f 
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
05 
CR2: 00007ffda9476d60 CR3: 0000000197533000 CR4: 00000000001406e0
<48> 
DR0: 0000000020000000 DR1: 0000000020000000 DR2: 0000000000000000
3d 
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
01 
Call Trace:
f0 ff 
 check_heap_object mm/usercopy.c:236 [inline]
 __check_object_size+0x4db/0x5f2 mm/usercopy.c:259
ff 
0f 
83 
eb 
 check_object_size include/linux/thread_info.h:119 [inline]
 check_copy_size include/linux/thread_info.h:150 [inline]
 copy_to_user include/linux/uaccess.h:154 [inline]
 bpf_test_finish.isra.7+0xd9/0x1f0 net/bpf/test_run.c:59
b9 
fb 
ff 
 bpf_prog_test_run_skb+0x7d7/0xa30 net/bpf/test_run.c:144
c3 
66 
2e 
0f 
1f 
84 00 
 bpf_prog_test_run+0x130/0x1a0 kernel/bpf/syscall.c:1686
00 00 
 __do_sys_bpf kernel/bpf/syscall.c:2323 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:2267 [inline]
 __x64_sys_bpf+0x3d8/0x510 kernel/bpf/syscall.c:2267
00 
RSP: 002b:00007fd899e03c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
RAX: ffffffffffffffda RBX: 00007fd899e046d4 RCX: 0000000000455ab9
RDX: 0000000000000028 RSI: 0000000020000080 RDI: 000000000000000a
RBP: 000000000072bff0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000004bb71f R14: 00000000004c8b00 R15: 0000000000000002

The buggy address belongs to the page:
page:ffffea000644ffc0 count:0 mapcount:0 mapping:0000000000000000 index:0x0
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
flags: 0x2fffc0000000000()
RIP: 0033:0x455ab9
raw: 02fffc0000000000 ffffea000644ffc8 ffffea000644ffc8 0000000000000000
Code: 1d 
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
ba 
page dumped because: kasan: bad access detected
fb 

ff 
Memory state around the buggy address:
c3 
 ffff8801913ffe80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
66 2e 
 ffff8801913fff00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
0f 
>ffff8801913fff80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
1f 
                                                                ^
84 00 
 ffff880191400000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 
 ffff880191400080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 
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