Bug 216364 - [Kernel IBT][kvm] There was "Missing ENDBR" in kvm when syzkaller tests
Summary: [Kernel IBT][kvm] There was "Missing ENDBR" in kvm when syzkaller tests
Status: RESOLVED CODE_FIX
Alias: None
Product: Virtualization
Classification: Unclassified
Component: kvm (show other bugs)
Hardware: All Linux
: P1 normal
Assignee: virtualization_kvm
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2022-08-15 06:25 UTC by xupengfe
Modified: 2022-08-19 06:13 UTC (History)
2 users (show)

See Also:
Kernel Version: v5.19 mainline kernel
Subsystem:
Regression: No
Bisected commit-id:


Attachments
Host_kernel_missing_endbr_from_kvm (314.55 KB, text/plain)
2022-08-15 06:25 UTC, xupengfe
Details
Fixed_patch_from_Peter_Z (131.50 KB, patch)
2022-08-17 11:05 UTC, xupengfe
Details | Diff

Description xupengfe 2022-08-15 06:25:25 UTC
Created attachment 301563 [details]
Host_kernel_missing_endbr_from_kvm

I used syzkaller and found the "Missing ENDBR: andw_ax_dx+0x0/0x10 [kvm]" BUG in the host.

Platform: ADL-P/TGL-U or TGL-H

Host Kernel:   v5.19 mainline kernel with kernel IBT
Guest kernel: v5.19 mainline kernel without kernel IBT, moved kconfig "CONFIG_X86_KERNEL_IBT=y".

Host kernel enabled kernel IBT by adding the KCONFIG "CONFIG_X86_KERNEL_IBT=y".

In syzkaller guest kernel, guest didn't enable kernel IBT and used 5.19 mainline kernel also.

After launched the syzkaller test about 2 hours.

There was  "Missing ENDBR: andw_ax_dx+0x0/0x10 [kvm]" info generated in host kernel.

[    0.000000] Linux version 5.19.0-m2 (root@xpf.sh.intel.com) (gcc (GCC) 8.5.0 20210514 (Red Hat 8.5.0-10), GNU ld version 2.36.1-2.el8) #1 SMP PREEMPT_DYNAMIC Mon Aug 1 14:23:55 CST 2022
[ 5048.057266] traps: Missing ENDBR: andw_ax_dx+0x0/0x10 [kvm]
[ 5048.057440] ------------[ cut here ]------------
[ 5048.057457] kernel BUG at arch/x86/kernel/traps.c:253!

Host dmesg was in attached.


Thanks!
Comment 1 xupengfe 2022-08-17 11:05:13 UTC
Created attachment 301591 [details]
Fixed_patch_from_Peter_Z
Comment 2 xupengfe 2022-08-17 11:05:50 UTC
Peter Zijlstra <peterz@infradead.org> gave the fixed patch.
I will have a try to verify the fixed patch.

Thanks!
Comment 3 xupengfe 2022-08-19 05:57:24 UTC
This issue was fixed by the patches in below link:

https://lore.kernel.org/lkml/64365019-57dc-b449-8178-30428e09adf8@redhat.com/

 

Verified it's could not be reproduced with syzkaller test for more than 4 hours on TGL-H and ADL-P.

Could close this issue.
Thanks!
Comment 4 xupengfe 2022-08-19 06:09:17 UTC
This issue was fixed by the patches in below link:

https://lore.kernel.org/lkml/64365019-57dc-b449-8178-30428e09adf8@redhat.com/

 

Verified it could not be reproduced with syzkaller test for more than 4 hours on TGL-H and ADL-P.

Could close this issue.
Thanks!

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