general protection fault in tss_update_io_bitmap

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit:    5d1131b4 Add linux-next specific files for 20191119
git tree:       linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=177979d2e00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=b60c562d89e5a8df
dashboard link: https://syzkaller.appspot.com/bug?extid=81e6ff9d4cdb05fd4f5e
compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=1549ed8ce00000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=17f91012e00000

The bug was bisected to:

commit 111e7b15cf10f6e973ccf537c70c66a5de539060
Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Date:   Tue Nov 12 20:40:33 2019 +0000

    x86/ioperm: Extend IOPL config to control ioperm() as well

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=10490e86e00000
final crash:    https://syzkaller.appspot.com/x/report.txt?x=12490e86e00000
console output: https://syzkaller.appspot.com/x/log.txt?x=14490e86e00000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+81e6ff9d4cdb05fd4f5e@xxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: 111e7b15cf10 ("x86/ioperm: Extend IOPL config to control ioperm() as  
well")

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
CPU: 0 PID: 8968 Comm: syz-executor566 Not tainted  
5.4.0-rc8-next-20191119-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
RIP: 0010:tss_update_io_bitmap+0x138/0x590 arch/x86/kernel/process.c:395
Code: 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 9e 03 00 00 4c 89  
ea 4c 8b 73 68 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <80> 3c 02 00 0f  
85 72 03 00 00 4d 3b 75 00 0f 85 35 02 00 00 48 8d
RSP: 0018:ffff8880a4effe80 EFLAGS: 00010046
RAX: dffffc0000000000 RBX: ffff8880ae80a000 RCX: ffffffff812a3228
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff8880ae80a068
RBP: ffff8880a4efff10 R08: 1ffff110126f5020 R09: ffffed10126f5021
R10: ffffed10126f5020 R11: ffff8880937a8107 R12: 1ffff110149dffd2
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000001e8f880(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffff01c2038 CR3: 0000000099c07000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 prepare_exit_to_usermode arch/x86/entry/common.c:201 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:278 [inline]
 do_syscall_64+0x685/0x790 arch/x86/entry/common.c:304
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4400f9
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:00007ffff000a2d8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ac
RAX: 0000000000000000 RBX: 00000000004002c8 RCX: 00000000004400f9
RDX: 0000000000400a20 RSI: 0000000000000012 RDI: 0000000000000003
RBP: 00000000006ca018 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 0000000000401980
R13: 0000000000401a10 R14: 0000000000000000 R15: 0000000000000000
Modules linked in:
---[ end trace 6bbd68071a8b58ba ]---
RIP: 0010:tss_update_io_bitmap+0x138/0x590 arch/x86/kernel/process.c:395
Code: 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 9e 03 00 00 4c 89  
ea 4c 8b 73 68 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <80> 3c 02 00 0f  
85 72 03 00 00 4d 3b 75 00 0f 85 35 02 00 00 48 8d
RSP: 0018:ffff8880a4effe80 EFLAGS: 00010046
RAX: dffffc0000000000 RBX: ffff8880ae80a000 RCX: ffffffff812a3228
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff8880ae80a068
RBP: ffff8880a4efff10 R08: 1ffff110126f5020 R09: ffffed10126f5021
R10: ffffed10126f5020 R11: ffff8880937a8107 R12: 1ffff110149dffd2
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000001e8f880(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffff01c2038 CR3: 0000000099c07000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


---
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