CVE-2022-49970

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Last Modified: UTC

Description

The MITRE CVE dictionary describes this issue as

In the Linux kernel, the following vulnerability has been resolved: bpf, cgroup: Fix kernel BUG in purge_effective_progs Syzkaller reported a triggered kernel BUG as follows: ------------[ cut here ]------------ kernel BUG at kernel/bpf/cgroup.c:925! invalid opcode: 0000 [#1] PREEMPT SMP NOPTI CPU: 1 PID: 194 Comm: detach Not tainted 5.19.0-14184-g69dac8e431af #8 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 RIP: 0010:__cgroup_bpf_detach+0x1f2/0x2a0 Code: 00 e8 92 60 30 00 84 c0 75 d8 4c 89 e0 31 f6 85 f6 74 19 42 f6 84 28 48 05 00 00 02 75 0e 48 8b 80 c0 00 00 00 48 85 c0 75 e5 <0f> 0b 48 8b 0c5 RSP: 0018:ffffc9000055bdb0 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff888100ec0800 RCX: ffffc900000f1000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff888100ec4578 RBP: 0000000000000000 R08: ffff888100ec0800 R09: 0000000000000040 R10: 0000000000000000 R11: 0000000000000000 R12: ffff888100ec4000 R13: 000000000000000d R14: ffffc90000199000 R15: ffff888100effb00 FS: 00007f68213d2b80(0000) GS:ffff88813bc80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055f74a0e5850 CR3: 0000000102836000 CR4: 00000000000006e0 Call Trace: <TASK> cgroup_bpf_prog_detach+0xcc/0x100 __sys_bpf+0x2273/0x2a00 __x64_sys_bpf+0x17/0x20 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f68214dbcb9 Code: 08 44 89 e0 5b 41 5c c3 66 0f 1f 84 00 00 00 00 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 ff8 RSP: 002b:00007ffeb487db68 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 000000000000000b RCX: 00007f68214dbcb9 RDX: 0000000000000090 RSI: 00007ffeb487db70 RDI: 0000000000000009 RBP: 0000000000000003 R08: 0000000000000012 R09: 0000000b00000003 R10: 00007ffeb487db70 R11: 0000000000000246 R12: 00007ffeb487dc20 R13: 0000000000000004 R14: 0000000000000001 R15: 000055f74a1011b0 </TASK> Modules linked in: ---[ end trace 0000000000000000 ]--- Repetition steps: For the following cgroup tree, root | cg1 | cg2 1. attach prog2 to cg2, and then attach prog1 to cg1, both bpf progs attach type is NONE or OVERRIDE. 2. write 1 to /proc/thread-self/fail-nth for failslab. 3. detach prog1 for cg1, and then kernel BUG occur. Failslab injection will cause kmalloc fail and fall back to purge_effective_progs. The problem is that cg2 have attached another prog, so when go through cg2 layer, iteration will add pos to 1, and subsequent operations will be skipped by the following condition, and cg will meet NULL in the end. `if (pos && !(cg->bpf.flags[atype] & BPF_F_ALLOW_MULTI))` The NULL cg means no link or prog match, this is as expected, and it's not a bug. So here just skip the no match situation.

Additional Information

External References

Content from www.cve.org is not included.https://www.cve.org/CVERecord?id=CVE-2022-49970

Content from nvd.nist.gov is not included.https://nvd.nist.gov/vuln/detail/CVE-2022-49970

Content from lore.kernel.org is not included.https://lore.kernel.org/linux-cve-announce/2025061817-CVE-2022-49970-2d63@gregkh/T

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 Not affected
Red Hat Enterprise Linux 7 kernel-rt Not affected
Red Hat Enterprise Linux 8 kernel Fix deferred
Red Hat Enterprise Linux 8 kernel-rt Fix deferred
Red Hat Enterprise Linux 9 kernel-rt Fix deferred
Red Hat Enterprise Linux 9 kernel Fixed RHSA-2023:2458
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 4.7 7.1
Attack Vector Local Local
Attack Complexity High Low
Privileges Required High Low
User Interaction None None
Scope Unchanged Unchanged
Confidentiality Impact None High
Integrity Impact Low None
Availability Impact High High

CVSS v3 Vector

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

NVD CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/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.