The 4.18.0-1015.15 Azure Kernel Panics Due to Missing Commit

Bug #1823805 reported by Joseph Salisbury
12
This bug affects 1 person
Affects Status Importance Assigned to Milestone
linux-azure (Ubuntu)
Fix Released
Undecided
Unassigned
Cosmic
Fix Released
Undecided
Marcelo Cerri

Bug Description

The following commit is being requested in the 18.04 4.18 based Bionic kernel for Azure:
c967590457ca scsi: storvsc: Fix a race in sub-channel creation that can cause panic

This commit was included when it was requested in bug 1805304. However, the 18.04 Bionic kernel for Azure was based on the upstream 4.15 kernel at that time. The patch was applied to the 4.15 based kernel as an Ubuntu SAUCE patch.

The 18.04 Bionic kernel for Azure has since been re-based to the 4.18 kernel. This requested commit was applied to mainline as of v4.20-rc6. The patch was cc’d to upstream stable, but upstream 4.18 was EOL by that point. Due to this, the patch never made it into any 4.18 kernels, which is why it is now missing from 18.04, it was rebased to 4.18.

This is a critical issue. The 4.18.0-1015 kernel immediately panics on boot without this commit.

Revision history for this message
Joseph Salisbury (jsalisbury) wrote :

The reason this missing commit is now causing a panic is because it Fixes the following commit, which is added by 4.18.0-1015:

c40598d9e67c vmbus: split ring buffer allocation from open

git describe --contains c40598d9e67c
Ubuntu-azure-4.18.0-1015.15_18.04.1~57

Revision history for this message
Joseph Salisbury (jsalisbury) wrote :

And looking a little further, commit ae6935ed7d42(Bionic commit c40598d9e67c) was added per bug 1812123 for DPDK. In that bug, we requested two commits:

b5679cebf780 ("vmbus: fix subchannel removal")
5e3c420dcca5 ("uio_hv_generic: set callbacks on open")

However, commit b5679cebf780 is a fix for commit ae6935ed7d42, so commit ae6935ed7d42 was also included. That then led to this bug, because with commit ae6935ed7d42, commit c967590457ca is now also needed.

description: updated
description: updated
Revision history for this message
Marcelo Cerri (mhcerri) wrote :
Changed in linux-azure (Ubuntu Cosmic):
status: New → In Progress
assignee: nobody → Marcelo Cerri (mhcerri)
Marcelo Cerri (mhcerri)
Changed in linux-azure (Ubuntu Cosmic):
status: In Progress → Fix Committed
Revision history for this message
Launchpad Janitor (janitor) wrote :
Download full text (15.2 KiB)

This bug was fixed in the package linux-azure - 4.18.0-1018.18

---------------
linux-azure (4.18.0-1018.18) cosmic; urgency=medium

  [ Ubuntu: 4.18.0-20.21 ]

  * CVE-2018-12126 // CVE-2018-12127 // CVE-2018-12130
    - Documentation/l1tf: Fix small spelling typo
    - x86/cpu: Sanitize FAM6_ATOM naming
    - kvm: x86: Report STIBP on GET_SUPPORTED_CPUID
    - locking/atomics, asm-generic: Move some macros from <linux/bitops.h> to a
      new <linux/bits.h> file
    - tools include: Adopt linux/bits.h
    - x86/msr-index: Cleanup bit defines
    - x86/speculation: Consolidate CPU whitelists
    - x86/speculation/mds: Add basic bug infrastructure for MDS
    - x86/speculation/mds: Add BUG_MSBDS_ONLY
    - x86/kvm: Expose X86_FEATURE_MD_CLEAR to guests
    - x86/speculation/mds: Add mds_clear_cpu_buffers()
    - x86/speculation/mds: Clear CPU buffers on exit to user
    - x86/kvm/vmx: Add MDS protection when L1D Flush is not active
    - x86/speculation/mds: Conditionally clear CPU buffers on idle entry
    - x86/speculation/mds: Add mitigation control for MDS
    - x86/speculation/mds: Add sysfs reporting for MDS
    - x86/speculation/mds: Add mitigation mode VMWERV
    - Documentation: Move L1TF to separate directory
    - Documentation: Add MDS vulnerability documentation
    - x86/speculation/mds: Add mds=full,nosmt cmdline option
    - x86/speculation: Move arch_smt_update() call to after mitigation decisions
    - x86/speculation/mds: Add SMT warning message
    - x86/speculation/mds: Fix comment
    - x86/speculation/mds: Print SMT vulnerable on MSBDS with mitigations off
    - x86/speculation/mds: Add 'mitigations=' support for MDS
  * CVE-2017-5715 // CVE-2017-5753
    - s390/speculation: Support 'mitigations=' cmdline option
  * CVE-2017-5715 // CVE-2017-5753 // CVE-2017-5754 // CVE-2018-3639
    - powerpc/speculation: Support 'mitigations=' cmdline option
  * CVE-2017-5715 // CVE-2017-5754 // CVE-2018-3620 // CVE-2018-3639 //
    CVE-2018-3646
    - cpu/speculation: Add 'mitigations=' cmdline option
    - x86/speculation: Support 'mitigations=' cmdline option
  * Packaging resync (LP: #1786013)
    - [Packaging] resync git-ubuntu-log

linux-azure (4.18.0-1017.17) cosmic; urgency=medium

  * linux-azure: 4.18.0-1017.17 -proposed tracker (LP: #1826166)

  * [linux-azure] Include mainline commits fc96df16a1ce and ba50bf1ce9a5 in
    Azure kernel (LP: #1821378)
    - Drivers: hv: vmbus: Return -EINVAL for the sys files for unopened channels
    - Drivers: hv: vmbus: Check for ring when getting debug info

  * [linux-azure] Commit To Improve NVMe Performance (LP: #1819689)
    - blk-mq: remove the request_list usage

  [ Ubuntu: 4.18.0-19.20 ]

  * linux: 4.18.0-19.20 -proposed tracker (LP: #1826171)
  * Packaging resync (LP: #1786013)
    - [Packaging] resync git-ubuntu-log
  * autopkgtests run too often, too much and don't skip enough (LP: #1823056)
    - [Debian] Set +x on rebuild testcase.
    - [Debian] Skip rebuild test, for regression-suite deps.
    - [Debian] Make ubuntu-regression-suite skippable on unbootable kernels.
    - [Debian] make rebuild use skippable error codes when skipping.
    - [Debian] Only run regression-suite...

Changed in linux-azure (Ubuntu Cosmic):
status: Fix Committed → Fix Released
Revision history for this message
Launchpad Janitor (janitor) wrote :
Download full text (15.7 KiB)

This bug was fixed in the package linux-azure - 4.18.0-1018.18~18.04.1

---------------
linux-azure (4.18.0-1018.18~18.04.1) bionic; urgency=medium

  [ Ubuntu: 4.18.0-1018.18 ]

  * CVE-2018-12126 // CVE-2018-12127 // CVE-2018-12130
    - Documentation/l1tf: Fix small spelling typo
    - x86/cpu: Sanitize FAM6_ATOM naming
    - kvm: x86: Report STIBP on GET_SUPPORTED_CPUID
    - locking/atomics, asm-generic: Move some macros from <linux/bitops.h> to a
      new <linux/bits.h> file
    - tools include: Adopt linux/bits.h
    - x86/msr-index: Cleanup bit defines
    - x86/speculation: Consolidate CPU whitelists
    - x86/speculation/mds: Add basic bug infrastructure for MDS
    - x86/speculation/mds: Add BUG_MSBDS_ONLY
    - x86/kvm: Expose X86_FEATURE_MD_CLEAR to guests
    - x86/speculation/mds: Add mds_clear_cpu_buffers()
    - x86/speculation/mds: Clear CPU buffers on exit to user
    - x86/kvm/vmx: Add MDS protection when L1D Flush is not active
    - x86/speculation/mds: Conditionally clear CPU buffers on idle entry
    - x86/speculation/mds: Add mitigation control for MDS
    - x86/speculation/mds: Add sysfs reporting for MDS
    - x86/speculation/mds: Add mitigation mode VMWERV
    - Documentation: Move L1TF to separate directory
    - Documentation: Add MDS vulnerability documentation
    - x86/speculation/mds: Add mds=full,nosmt cmdline option
    - x86/speculation: Move arch_smt_update() call to after mitigation decisions
    - x86/speculation/mds: Add SMT warning message
    - x86/speculation/mds: Fix comment
    - x86/speculation/mds: Print SMT vulnerable on MSBDS with mitigations off
    - x86/speculation/mds: Add 'mitigations=' support for MDS
  * CVE-2017-5715 // CVE-2017-5753
    - s390/speculation: Support 'mitigations=' cmdline option
  * CVE-2017-5715 // CVE-2017-5753 // CVE-2017-5754 // CVE-2018-3639
    - powerpc/speculation: Support 'mitigations=' cmdline option
  * CVE-2017-5715 // CVE-2017-5754 // CVE-2018-3620 // CVE-2018-3639 //
    CVE-2018-3646
    - cpu/speculation: Add 'mitigations=' cmdline option
    - x86/speculation: Support 'mitigations=' cmdline option
  * Packaging resync (LP: #1786013)
    - [Packaging] resync git-ubuntu-log

linux-azure (4.18.0-1017.17~18.04.1) bionic; urgency=medium

  * linux-azure: 4.18.0-1017.17~18.04.1 -proposed tracker (LP: #1826165)

  * Packaging resync (LP: #1786013)
    - [Packaging] update helper scripts

  [ Ubuntu: 4.18.0-1017.17 ]

  * linux-azure: 4.18.0-1017.17 -proposed tracker (LP: #1826166)
  * [linux-azure] Include mainline commits fc96df16a1ce and ba50bf1ce9a5 in
    Azure kernel (LP: #1821378)
    - Drivers: hv: vmbus: Return -EINVAL for the sys files for unopened channels
    - Drivers: hv: vmbus: Check for ring when getting debug info
  * [linux-azure] Commit To Improve NVMe Performance (LP: #1819689)
    - blk-mq: remove the request_list usage
  * linux: 4.18.0-19.20 -proposed tracker (LP: #1826171)
  * Packaging resync (LP: #1786013)
    - [Packaging] resync git-ubuntu-log
  * autopkgtests run too often, too much and don't skip enough (LP: #1823056)
    - [Debian] Set +x on rebuild testcase.
    - [Debian] Skip rebuild test, for regression-suite deps.
    - [Deb...

Changed in linux-azure (Ubuntu):
status: New → Fix Released
Revision history for this message
Steve Langasek (vorlon) wrote : Update Released

The verification of the Stable Release Update for linux-azure has completed successfully and the package has now been released to -updates. Subsequently, the Ubuntu Stable Release Updates Team is being unsubscribed and will not receive messages about this bug report. In the event that you encounter a regression using the package from -updates please report a new bug using ubuntu-bug and tag the bug report regression-update so we can easily find any regressions.

To post a comment you must log in.
This report contains Public information  
Everyone can see this information.

Other bug subscribers

Remote bug watches

Bug watches keep track of this bug in other bug trackers.