general protection fault in bpf_clone_redirect (2)

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 987732fc ANDROID: Add a tracepoint for mapping inode to fu..
git tree: android-4.14
console output: https://syzkaller.appspot.com/x/log.txt?x=13ff782a600000
kernel config: https://syzkaller.appspot.com/x/.config?x=db048054ce6f3d49
dashboard link: https://syzkaller.appspot.com/bug?extid=d46cff893ea0799b55bd
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=178b1c66600000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1702f6a2600000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+d46cff...@syzkaller.appspotmail.com

audit: type=1400 audit(1567206683.969:7): avc: denied { map } for
pid=1779 comm="syz-executor195" path="/root/syz-executor195311216"
dev="sda1" ino=16482 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023
tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1
audit: type=1400 audit(1567206683.999:8): avc: denied { prog_load } for
pid=1779 comm="syz-executor195"
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(1567206684.019:9): avc: denied { prog_run } for
pid=1779 comm="syz-executor195"
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
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN NOPTI
Modules linked in:
CPU: 0 PID: 1779 Comm: syz-executor195 Not tainted 4.14.140+ #39
task: (ptrval) task.stack: (ptrval)
RIP: 0010:read_pnet include/net/net_namespace.h:282 [inline]
RIP: 0010:dev_net include/linux/netdevice.h:2015 [inline]
RIP: 0010:____bpf_clone_redirect net/core/filter.c:1768 [inline]
RIP: 0010:bpf_clone_redirect+0x6a/0x2b0 net/core/filter.c:1759
RSP: 0018:ffff8881cfc1f808 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff8881d697ae20 RCX: 00000000607cfff9
RDX: 00000000000000a7 RSI: 0000000000000006 RDI: 0000000000000538
RBP: 0000000000000000 R08: ffffffffa9dfd0bb R09: ffffed103b7444fa
R10: ffffed103b7444f9 R11: ffff8881dba227cf R12: 0000000000000000
R13: 0000000000000006 R14: ffffffffaafb97e0 R15: ffffc90000496088
FS: 0000000000a19880(0000) GS:ffff8881dba00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000200 CR3: 00000001d1288006 CR4: 00000000001606b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
___bpf_prog_run+0x2478/0x5510 kernel/bpf/core.c:1086
Code: 48 c1 ea 03 80 3c 02 00 0f 85 55 02 00 00 48 b8 00 00 00 00 00 fc ff
df 4c 8b 63 10 49 8d bc 24 38 05 00 00 48 89 fa 48 c1 ea 03 <80> 3c 02 00
0f 85 12 02 00 00 49 8b bc 24 38 05 00 00 44 89 ee
RIP: read_pnet include/net/net_namespace.h:282 [inline] RSP:
ffff8881cfc1f808
RIP: dev_net include/linux/netdevice.h:2015 [inline] RSP: ffff8881cfc1f808
RIP: ____bpf_clone_redirect net/core/filter.c:1768 [inline] RSP:
ffff8881cfc1f808
RIP: bpf_clone_redirect+0x6a/0x2b0 net/core/filter.c:1759 RSP:
ffff8881cfc1f808
---[ end trace 7f4889397ebda4c3 ]---
Kernel panic - not syncing: Fatal exception
Kernel Offset: 0x28c00000 from 0xffffffff81000000 (relocation range:
0xffffffff80000000-0xffffffffbfffffff)
Rebooting in 86400 seconds..


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