CVE-2021-46974 (GCVE-0-2021-46974)

Vulnerability from cvelistv5 – Published: 2024-02-27 18:47 – Updated: 2025-05-04 12:40
VLAI?
Title
bpf: Fix masking negation logic upon negative dst register
Summary
In the Linux kernel, the following vulnerability has been resolved: bpf: Fix masking negation logic upon negative dst register The negation logic for the case where the off_reg is sitting in the dst register is not correct given then we cannot just invert the add to a sub or vice versa. As a fix, perform the final bitwise and-op unconditionally into AX from the off_reg, then move the pointer from the src to dst and finally use AX as the source for the original pointer arithmetic operation such that the inversion yields a correct result. The single non-AX mov in between is possible given constant blinding is retaining it as it's not an immediate based operation.
Severity ?
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: ae03b6b1c880a03d4771257336dc3bca156dd51b , < 4d542ddb88fb2f39bf7f14caa2902f3e8d06f6ba (git)
Affected: f92a819b4cbef8c9527d9797110544b2055a4b96 , < 0e2dfdc74a7f4036127356d42ea59388f153f42c (git)
Affected: 979d63d50c0c0f7bc537bf821e056cc9fe5abd38 , < 53e0db429b37a32b8fc706d0d90eb4583ad13848 (git)
Affected: 979d63d50c0c0f7bc537bf821e056cc9fe5abd38 , < 2cfa537674cd1051a3b8111536d77d0558f33d5d (git)
Affected: 979d63d50c0c0f7bc537bf821e056cc9fe5abd38 , < 6eba92a4d4be8feb4dc33976abac544fa99d6ecc (git)
Affected: 979d63d50c0c0f7bc537bf821e056cc9fe5abd38 , < 7cf64d8679ca1cb20cf57d6a88bfee79a0922a66 (git)
Affected: 979d63d50c0c0f7bc537bf821e056cc9fe5abd38 , < b9b34ddbe2076ade359cd5ce7537d5ed019e9807 (git)
Affected: 078da99d449f64ca04d459cdbdcce513b64173cd (git)
Create a notification for this product.
    Linux Linux Affected: 5.0
Unaffected: 0 , < 5.0 (semver)
Unaffected: 4.14.233 , ≤ 4.14.* (semver)
Unaffected: 4.19.190 , ≤ 4.19.* (semver)
Unaffected: 5.4.117 , ≤ 5.4.* (semver)
Unaffected: 5.10.35 , ≤ 5.10.* (semver)
Unaffected: 5.11.19 , ≤ 5.11.* (semver)
Unaffected: 5.12.2 , ≤ 5.12.* (semver)
Unaffected: 5.13 , ≤ * (original_commit_for_fix)
Create a notification for this product.
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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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