syzbot


general protection fault in __apic_accept_irq (2)

Status: fixed on 2020/08/01 00:49
Subsystems: kvm
[Documentation on labels]
Reported-by: syzbot+1bf777dfdde86d64b89b@syzkaller.appspotmail.com
Fix commit: 9d3c447c72fb KVM: X86: Fix async pf caused null-ptr-deref
First crash: 1571d, last: 1571d
Cause bisection: introduced by (bisect log) [merge commit]:
commit f1e455352b6f503532eb3637d0a6d991895e7856
Author: Linus Torvalds <torvalds@linux-foundation.org>
Date: Wed Jun 3 21:57:03 2020 +0000

  Merge tag 'kgdb-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/danielt/linux

Crash: KASAN: vmalloc-out-of-bounds Read in srcu_invoke_callbacks (log)
Repro: C syz .config
  
Discussions (2)
Title Replies (including bot) Last reply
[PATCH] KVM: X86: Fix async pf caused null-ptr-deref 6 (6) 2020/06/30 00:16
general protection fault in __apic_accept_irq (2) 0 (1) 2020/06/29 08:51
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream general protection fault in __apic_accept_irq C done 69 1852d 1865d 13/28 fixed on 2019/10/15 23:40

Sample crash report:
L1TF CPU bug present and SMT on, data leak possible. See CVE-2018-3646 and https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/l1tf.html for details.
general protection fault, probably for non-canonical address 0xdffffc0000000013: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000098-0x000000000000009f]
CPU: 1 PID: 6780 Comm: syz-executor153 Not tainted 5.7.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__apic_accept_irq+0x46/0xb80 arch/x86/kvm/lapic.c:1039
Code: 4c 24 18 4c 89 4c 24 08 e8 67 0d 61 00 49 8d 87 98 00 00 00 48 89 c2 48 89 44 24 20 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <80> 3c 02 00 0f 85 1b 0a 00 00 49 8b af 98 00 00 00 0f 1f 44 00 00
RSP: 0018:ffffc900015f79a8 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff888095b00040 RCX: 0000000000000000
RDX: 0000000000000013 RSI: ffffffff8112c159 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000003 R11: fffff520002bef4c R12: 0000000000000000
R13: ffff8880a00b8e68 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000001193880(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa6130226c0 CR3: 00000000a1257000 CR4: 00000000001426e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 kvm_arch_async_page_present+0x7de/0x9e0 arch/x86/kvm/x86.c:10580
 kvm_check_async_pf_completion+0x18d/0x400 arch/x86/kvm/../../../virt/kvm/async_pf.c:151
 vcpu_enter_guest arch/x86/kvm/x86.c:8437 [inline]
 vcpu_run arch/x86/kvm/x86.c:8669 [inline]
 kvm_arch_vcpu_ioctl_run+0x18bf/0x69f0 arch/x86/kvm/x86.c:8890
 kvm_vcpu_ioctl+0x46a/0xe20 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3163
 vfs_ioctl fs/ioctl.c:47 [inline]
 ksys_ioctl+0x11a/0x180 fs/ioctl.c:771
 __do_sys_ioctl fs/ioctl.c:780 [inline]
 __se_sys_ioctl fs/ioctl.c:778 [inline]
 __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:778
 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x49/0xb3
RIP: 0033:0x440299
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:00007ffc336022f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440299
RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000005
RBP: 00000000006ca018 R08: 00000000004002c8 R09: 00000000004002c8
R10: 00000000004002c8 R11: 0000000000000246 R12: 0000000000401b20
R13: 0000000000401bb0 R14: 0000000000000000 R15: 0000000000000000
Modules linked in:
---[ end trace 85b25eaa183f3d19 ]---
RIP: 0010:__apic_accept_irq+0x46/0xb80 arch/x86/kvm/lapic.c:1039
Code: 4c 24 18 4c 89 4c 24 08 e8 67 0d 61 00 49 8d 87 98 00 00 00 48 89 c2 48 89 44 24 20 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <80> 3c 02 00 0f 85 1b 0a 00 00 49 8b af 98 00 00 00 0f 1f 44 00 00
RSP: 0018:ffffc900015f79a8 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff888095b00040 RCX: 0000000000000000
RDX: 0000000000000013 RSI: ffffffff8112c159 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000003 R11: fffff520002bef4c R12: 0000000000000000
R13: ffff8880a00b8e68 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000001193880(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000560b8ba34fa8 CR3: 00000000a1257000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

Crashes (9):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/06/25 09:27 upstream 7ae77150d94d 54566aff .config console log report syz C ci-upstream-kasan-gce
2020/06/25 09:27 upstream 7ae77150d94d 54566aff .config console log report syz C ci-upstream-kasan-gce-root
2020/06/25 09:21 upstream 7ae77150d94d 54566aff .config console log report syz C ci-upstream-kasan-gce-selinux-root
2020/06/25 09:15 upstream 7ae77150d94d 54566aff .config console log report syz C ci-upstream-kasan-gce-smack-root
2020/06/25 08:57 upstream 7ae77150d94d 54566aff .config console log report syz C ci-upstream-kasan-gce-386
2020/06/25 09:26 upstream 7ae77150d94d 54566aff .config console log report ci-upstream-kasan-gce
2020/06/25 09:12 upstream 7ae77150d94d 54566aff .config console log report ci-upstream-kasan-gce-selinux-root
2020/06/25 09:17 upstream 7ae77150d94d 54566aff .config console log report ci-upstream-kasan-gce-386
2020/06/25 08:42 upstream 7ae77150d94d 54566aff .config console log report ci-upstream-kasan-gce-386
* Struck through repros no longer work on HEAD.