CVE-2021-47317
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…
Does this matter?
Lower severity and a low EPSS score (0.19%). Track it; it rarely justifies an emergency change on its own.
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 3.1
- 3.3 LOWCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
- EPSS
- 0.19% probability · 8th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-667
- Affected
- linux/linux kernel
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/0d435b6d94b05dcfd836d758a63145aa566618e2Patch
- https://git.kernel.org/stable/c/419ac821766cbdb9fd85872bb3f1a589df05c94cPatch
- https://git.kernel.org/stable/c/7284dab07e4d51d453cc42851fae9ec4fac6ef2fPatch
- https://git.kernel.org/stable/c/0d435b6d94b05dcfd836d758a63145aa566618e2Patch
- https://git.kernel.org/stable/c/419ac821766cbdb9fd85872bb3f1a589df05c94cPatch
- https://git.kernel.org/stable/c/7284dab07e4d51d453cc42851fae9ec4fac6ef2fPatch
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.