general protection fault in __rb_insert_augmented

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: d71f695c Linux 4.14.179
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1764f0d0100000
kernel config: https://syzkaller.appspot.com/x/.config?x=580f01c69a690433
dashboard link: https://syzkaller.appspot.com/bug?extid=9d4c8b3a4c3fa87e95a4
compiler: gcc (GCC) 9.0.0 20181231 (experimental)

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+9d4c8b...@syzkaller.appspotmail.com

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
Modules linked in:
CPU: 0 PID: 6349 Comm: syz-executor.0 Not tainted 4.14.179-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8880600bc640 task.stack: ffff8880600c0000
RIP: 0010:__rb_insert lib/rbtree.c:131 [inline]
RIP: 0010:__rb_insert_augmented+0x95/0xc90 lib/rbtree.c:495
RSP: 0018:ffff8880600c7be0 EFLAGS: 00010202
RAX: ffff8880a9c012a8 RBX: ffff88809ec9a8d8 RCX: 0000000000000000
RDX: 0000000000000001 RSI: dffffc0000000000 RDI: 1ffff1100a51a2f2
RBP: 0000000000000000 R08: 0000000000000008 R09: ffffffff8a080f08
R10: ffff8880600bcf40 R11: ffff8880600bc640 R12: ffff8880001cc058
R13: dffffc0000000000 R14: ffff8880a8b6cf08 R15: ffffffff8177c3d0
FS: 0000000001d66940(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c4332a9000 CR3: 000000006009e000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
dup_mmap kernel/fork.c:681 [inline]
dup_mm kernel/fork.c:1199 [inline]
copy_mm kernel/fork.c:1254 [inline]
copy_process.part.0+0x42d9/0x6a50 kernel/fork.c:1771
copy_process kernel/fork.c:1586 [inline]
_do_fork+0x180/0xc80 kernel/fork.c:2070
do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45ae5a
RSP: 002b:00007fff0caef060 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007fff0caef060 RCX: 000000000045ae5a
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 00007fff0caef0a0 R08: 0000000000000001 R09: 0000000001d66940
R10: 0000000001d66c10 R11: 0000000000000246 R12: 0000000000000001
R13: 0000000000000000 R14: 0000000000000000 R15: 00007fff0caef0f0
Code: 4c 89 e2 48 c1 ea 03 42 80 3c 2a 00 0f 85 44 07 00 00 49 8b 2c 24 40 f6 c5 01 0f 85 3e 06 00 00 4c 8d 45 08 4c 89 c2 48 c1 ea 03 <42> 80 3c 2a 00 0f 85 5c 07 00 00 4c 8b 75 08 4d 39 e6 0f 84 92
RIP: __rb_insert lib/rbtree.c:131 [inline] RSP: ffff8880600c7be0
RIP: __rb_insert_augmented+0x95/0xc90 lib/rbtree.c:495 RSP: ffff8880600c7be0
---[ end trace 6cb3ecdfc7358022 ]---


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.