CVE-2021-47317

LOW EPSS 7.1%
Published May 21, 20242y ago · Modified Jun 17, 20262w ago
3.3 CVSS 3.1
Low
Find Similar
Published May 21, 2024 2y ago
Last Modified Jun 17, 2026 2w ago

Description

In the Linux kernel, the following vulnerability has been resolved: powerpc/bpf: Fix detecting BPF atomic instructions Commit 91c960b0056672 ("bpf: Rename BPF_XADD and prepare to encode other atomics in .imm") converted BPF_XADD to BPF_ATOMIC and added a way to distinguish instructions based on the immediate field. Existing JIT implementations were updated to check for the immediate field and to reject programs utilizing anything more than BPF_ADD (such as BPF_FETCH) in the immediate field. However, the check added to powerpc64 JIT did not look at the correct BPF instruction. Due to this, such programs would be accepted and incorrectly JIT'ed resulting in soft lockups, as seen with the atomic bounds test. Fix this by looking at the correct immediate value.

CVSS Details

Base Score
3.3
Exploitability
1.8
Impact
1.4
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
Attack Vector Local
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality None
Integrity None
Availability Low

Threat Intelligence

EPSS Exploit Probability
7.1% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Weaknesses 1

CWE-667

Affected Products 2

VendorProductVersionRange
linuxlinux_kernel*≥5.12  –  <5.12.19
linuxlinux_kernel*≥5.13  –  <5.13.4

References 3

  • git.kernel.org https://git.kernel.org/stable/c/0d435b6d94b05dcfd836d758a63145aa566618e2
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/419ac821766cbdb9fd85872bb3f1a589df05c94c
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/7284dab07e4d51d453cc42851fae9ec4fac6ef2f
    Patch

Remediation

  • git.kernel.org https://git.kernel.org/stable/c/0d435b6d94b05dcfd836d758a63145aa566618e2
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/419ac821766cbdb9fd85872bb3f1a589df05c94c
    Patch
  • git.kernel.org https://git.kernel.org/stable/c/7284dab07e4d51d453cc42851fae9ec4fac6ef2f
    Patch