CVE-2022-50700

Public on

Last Modified: UTC

Description

The MITRE CVE dictionary describes this issue as

In the Linux kernel, the following vulnerability has been resolved: wifi: ath10k: Delay the unmapping of the buffer On WCN3990, we are seeing a rare scenario where copy engine hardware is sending a copy complete interrupt to the host driver while still processing the buffer that the driver has sent, this is leading into an SMMU fault triggering kernel panic. This is happening on copy engine channel 3 (CE3) where the driver normally enqueues WMI commands to the firmware. Upon receiving a copy complete interrupt, host driver will immediately unmap and frees the buffer presuming that hardware has processed the buffer. In the issue case, upon receiving copy complete interrupt, host driver will unmap and free the buffer but since hardware is still accessing the buffer (which in this case got unmapped in parallel), SMMU hardware will trigger an SMMU fault resulting in a kernel panic. In order to avoid this, as a work around, add a delay before unmapping the copy engine source DMA buffer. This is conditionally done for WCN3990 and only for the CE3 channel where issue is seen. Below is the crash signature: wifi smmu error: kernel: [ 10.120965] arm-smmu 15000000.iommu: Unhandled context fault: fsr=0x402, iova=0x7fdfd8ac0, fsynr=0x500003,cbfrsynra=0xc1, cb=6 arm-smmu 15000000.iommu: Unhandled context fault:fsr=0x402, iova=0x7fe06fdc0, fsynr=0x710003, cbfrsynra=0xc1, cb=6 qcom-q6v5-mss 4080000.remoteproc: fatal error received: err_qdi.c:1040:EF:wlan_process:0x1:WLAN RT:0x2091: cmnos_thread.c:3998:Asserted in copy_engine.c:AXI_ERROR_DETECTED:2149 remoteproc remoteproc0: crash detected in 4080000.remoteproc: type fatal error <3> remoteproc remoteproc0: handling crash #1 in 4080000.remoteproc pc : __arm_lpae_unmap+0x500/0x514 lr : __arm_lpae_unmap+0x4bc/0x514 sp : ffffffc011ffb530 x29: ffffffc011ffb590 x28: 0000000000000000 x27: 0000000000000000 x26: 0000000000000004 x25: 0000000000000003 x24: ffffffc011ffb890 x23: ffffffa762ef9be0 x22: ffffffa77244ef00 x21: 0000000000000009 x20: 00000007fff7c000 x19: 0000000000000003 x18: 0000000000000000 x17: 0000000000000004 x16: ffffffd7a357d9f0 x15: 0000000000000000 x14: 00fd5d4fa7ffffff x13: 000000000000000e x12: 0000000000000000 x11: 00000000ffffffff x10: 00000000fffffe00 x9 : 000000000000017c x8 : 000000000000000c x7 : 0000000000000000 x6 : ffffffa762ef9000 x5 : 0000000000000003 x4 : 0000000000000004 x3 : 0000000000001000 x2 : 00000007fff7c000 x1 : ffffffc011ffb890 x0 : 0000000000000000 Call trace: __arm_lpae_unmap+0x500/0x514 __arm_lpae_unmap+0x4bc/0x514 __arm_lpae_unmap+0x4bc/0x514 arm_lpae_unmap_pages+0x78/0xa4 arm_smmu_unmap_pages+0x78/0x104 __iommu_unmap+0xc8/0x1e4 iommu_unmap_fast+0x38/0x48 __iommu_dma_unmap+0x84/0x104 iommu_dma_free+0x34/0x50 dma_free_attrs+0xa4/0xd0 ath10k_htt_rx_free+0xc4/0xf4 [ath10k_core] ath10k_core_stop+0x64/0x7c [ath10k_core] ath10k_halt+0x11c/0x180 [ath10k_core] ath10k_stop+0x54/0x94 [ath10k_core] drv_stop+0x48/0x1c8 [mac80211] ieee80211_do_open+0x638/0x77c [mac80211] ieee80211_open+0x48/0x5c [mac80211] __dev_open+0xb4/0x174 __dev_change_flags+0xc4/0x1dc dev_change_flags+0x3c/0x7c devinet_ioctl+0x2b4/0x580 inet_ioctl+0xb0/0x1b4 sock_do_ioctl+0x4c/0x16c compat_ifreq_ioctl+0x1cc/0x35c compat_sock_ioctl+0x110/0x2ac __arm64_compat_sys_ioctl+0xf4/0x3e0 el0_svc_common+0xb4/0x17c el0_svc_compat_handler+0x2c/0x58 el0_svc_compat+0x8/0x2c Tested-on: WCN3990 hw1.0 SNOC WLAN.HL.2.0-01387-QCAHLSWMTPLZ-1

Affected Packages and Issued Red Hat Security Errata

Products / Services Components State Errata
Red Hat Enterprise Linux 10 kernel Not affected
Red Hat Enterprise Linux 6 kernel Not affected
Red Hat Enterprise Linux 7 kernel Fix deferred
Red Hat Enterprise Linux 7 kernel-rt Fix deferred
Red Hat Enterprise Linux 8 kernel-rt Fix deferred
Red Hat Enterprise Linux 8 kernel Fixed RHSA-2023:7077
Red Hat Enterprise Linux 9 kernel-rt Fix deferred
Red Hat Enterprise Linux 9 kernel Fixed RHSA-2023:6583
Unless explicitly stated as not affected, all previous versions of packages in any minor update stream of a product listed here should be assumed vulnerable, although may not have been subject to full analysis.

Common Vulnerability Scoring System (CVSS) Score Details

Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authorities (CNA) source for its products and services (see Red Hat classifications ).

CVSS v3 Score Breakdown Red Hat NVD
CVSS v3 Base Score 5.3
Attack Vector Local
Attack Complexity High
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality Impact None
Integrity Impact Low
Availability Impact High

CVSS v3 Vector

Red Hat CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:H

Frequently Asked Questions

Why is Red Hat's CVSS v3 score or Impact different from other vendors?

For open source software shipped by multiple vendors, the CVSS base scores may vary for each vendor's version depending on the version they ship, how they ship it, the platform, and even how the software is compiled. This makes scoring of vulnerabilities difficult for third-party vulnerability databases such as NVD that only provide a single CVSS base score for each vulnerability. Red Hat scores reflect how a vulnerability affects our products specifically.

For more information, see https://access.redhat.com/solutions/762393.

My product is listed as "Under investigation" or "Affected", when will Red Hat release a fix for this vulnerability?

  • "Under investigation" doesn't necessarily mean that the product is affected by this vulnerability. It only means that our Analysis Team is still working on determining whether the product is affected and how it is affected.
  • "Affected" means that our Analysis Team has determined that this product is affected by this vulnerability and might release a fix to address this in the near future.

What can I do if my product is listed as "Will not fix"?

A "will not fix" status means that a fix for an affected product version is not planned or not possible due to complexity, which may create additional risk.

Available options depend mostly on the Impact of the vulnerability and the current Life Cycle phase of your product. Overall, you have the following options:
  • Upgrade to a supported product version that includes a fix for this vulnerability (recommended).
  • Apply a mitigation (if one exists).
  • Open a This content is not included.support case to request a prioritization of releasing a fix for this vulnerability.

What can I do if my product is listed as "Fix deferred"?

A deferred status means that a fix for an affected product version is not guaranteed due to higher-priority development work.

Available options depend mostly on the Impact of the vulnerability and the current Life Cycle phase of your product. Overall, you have the following options:
  • Apply a mitigation (if one exists).
  • Open a This content is not included.support case to request a prioritization of releasing a fix for this vulnerability.
  • Red Hat Engineering focuses on addressing high-priority issues based on their complexity or limited lifecycle support. Therefore, lower-priority issues will not receive immediate fixes.

What is a mitigation?

A mitigation is an action that can be taken to reduce the impact of a security vulnerability, without deploying any fixes.

I have a Red Hat product but it is not in the above list, is it affected?

The listed products were found to include one or more of the components that this vulnerability affects. These products underwent a thorough evaluation to determine their affectedness by this vulnerability. Note that layered products (such as container-based offerings) that consume affected components from any of the products listed in this table may be affected and are not represented.

Why is my security scanner reporting my product as vulnerable to this vulnerability even though my product version is fixed or not affected?

In order to maintain code stability and compatibility, Red Hat usually does not rebase packages to entirely new versions. Instead, we backport fixes and new features to an older version of the package we distribute. This can result in some security scanners that only consider the package version to report the package as vulnerable. To avoid this, we suggest that you use an approved vulnerability scanner from our This content is not included.Red Hat Vulnerability Scanner Certification program.

My product is listed as "Out of Support Scope". What does this mean?

When a product is listed as "Out of Support Scope", it means a vulnerability with the impact level assigned to this CVE is no longer covered by its current support lifecycle phase. The product has been identified to contain the impacted component, but analysis to determine whether it is affected or not by this vulnerability was not performed. The product should be assumed to be affected. Customers are advised to apply any mitigation options documented on this page, consider removing or disabling the impacted component, or upgrade to a supported version of the product that has an update available.