Tracker / CVE-2021-46974
CVE-2021-46974
High 7.1
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.
Affected products and versions
| linux | linux_kernel · 4.14.113 → 4.14.233 |
|---|---|
| linux | linux_kernel · 4.19.19 → 4.19.190 |
| linux | linux_kernel · 5.0 → 5.4.117 |
| linux | linux_kernel · 5.11 → 5.11.19 |
| linux | linux_kernel · 5.12 → 5.12.2 |
| linux | linux_kernel · 5.5 → 5.10.35 |
Analysis
This page is not indexable yet.Until it carries original analysis — what it actually exposes, how to check in two minutes whether a system was touched, what to do if it was — the page stays noindex. The database decides that, not the template.