kernel BUG at mm/slab.c:LINE! (2)

syzbot
2018-07-09T06:16:10Z

Hello,

syzbot found the following crash on:

HEAD commit: d90c936fb318 Merge branch 'bpf-nfp-mul-div-support'
git tree: bpf-next
console output: https://syzkaller.appspot.com/x/log.txt?x=15cf4f48400000
kernel config: https://syzkaller.appspot.com/x/.config?x=a501a01deaf0fe9
dashboard link: https://syzkaller.appspot.com/bug?extid=885bda95271928dc24eb
compiler: gcc (GCC) 8.0.1 20180413 (experimental)
syzkaller repro:https://syzkaller.appspot.com/x/repro.syz?x=15c87748400000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1459050c400000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+885bda95271928dc24eb@syzkaller.appspotmail.com

random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
------------[ cut here ]------------
kernel BUG at mm/slab.c:4421!
invalid opcode: 0000 [#1] SMP KASAN
CPU: 0 PID: 4467 Comm: syz-executor607 Not tainted 4.18.0-rc3+ #48
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
RIP: 0010:__check_heap_object+0xa7/0xb5 mm/slab.c:4446
Code: 48 c7 c7 90 73 c0 88 e8 87 7a 08 00 5d c3 41 8b 91 04 01 00 00 48 29
c7 48 39 d7 77 be 48 01 d0 48 29 c8 48 39 f0 72 b3 5d c3 <0f> 0b 48 c7 c7
90 73 c0 88 e8 6d 81 08 00 44 89 e1 4c 8d 45 c4 48
RSP: 0018:ffff8801ab117a10 EFLAGS: 00010246
RAX: 0000000000000006 RBX: 1ffff10035622f49 RCX: 0000000000000009
RDX: ffff8801c27ff000 RSI: 00000000000003d2 RDI: ffff8801c27ffff2
RBP: ffff8801ab117a10 R08: ffff8801ab37a680 R09: ffff8801da800940
R10: 0000000000000991 R11: 0000000000000001 R12: ffff8801c27ffff2
R13: 00000000000003d2 R14: 0000000000000001 R15: ffffea000709ffc0
FS: 0000000000763880(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000200 CR3: 00000001b0a8b000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
check_heap_object mm/usercopy.c:236 [inline]
__check_object_size+0x4db/0x5f2 mm/usercopy.c:259
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
bpf_prog_test_run_skb+0x7d7/0xa30 net/bpf/test_run.c:144
bpf_prog_test_run+0x130/0x1a0 kernel/bpf/syscall.c:1686
__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
do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4402d9
Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 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 0f 83 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fff168c6558 EFLAGS: 00000213 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004402d9
RDX: 0000000000000028 RSI: 0000000020000080 RDI: 000000000000000a
RBP: 00000000006ca018 R08: 00000000004002c8 R09: 00000000004002c8
R10: 0000000000000000 R11: 0000000000000213 R12: 0000000000401b60
R13: 0000000000401bf0 R14: 0000000000000000 R15: 0000000000000000
Modules linked in:
Dumping ftrace buffer:
(ftrace buffer empty)
---[ end trace 045402f983996608 ]---
RIP: 0010:__check_heap_object+0xa7/0xb5 mm/slab.c:4446
Code: 48 c7 c7 90 73 c0 88 e8 87 7a 08 00 5d c3 41 8b 91 04 01 00 00 48 29
c7 48 39 d7 77 be 48 01 d0 48 29 c8 48 39 f0 72 b3 5d c3 <0f> 0b 48 c7 c7
90 73 c0 88 e8 6d 81 08 00 44 89 e1 4c 8d 45 c4 48
RSP: 0018:ffff8801ab117a10 EFLAGS: 00010246
RAX: 0000000000000006 RBX: 1ffff10035622f49 RCX: 0000000000000009
RDX: ffff8801c27ff000 RSI: 00000000000003d2 RDI: ffff8801c27ffff2
RBP: ffff8801ab117a10 R08: ffff8801ab37a680 R09: ffff8801da800940
R10: 0000000000000991 R11: 0000000000000001 R12: ffff8801c27ffff2
R13: 00000000000003d2 R14: 0000000000000001 R15: ffffea000709ffc0
FS: 0000000000763880(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000200 CR3: 00000001b0a8b000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

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