In the Linux kernel, the following vulnerability has been resolved: bpf: Fix unsound scalar forking in maybe_fork_scalars() for BPF_OR maybe_fork_scalars() is called for both BPF_AND and BPF_OR when the source operand is a constant. When dst has signed range [-1, 0], it forks the verifier state: the pushed path gets dst = 0, the current path gets dst = -1. For BPF_AND this is correct: 0 & K == 0. For BPF_OR this is wrong: 0 | K == K, not 0. The pushed path therefore tracks dst as 0 when the runtime value is K, producing an exploitable verifier/runtime divergence that allows out-of-bounds map access. Fix this by passing env->insn_idx (instead of env->insn_idx + 1) to push_stack(), so the pushed path re-executes the ALU instruction with dst = 0 and naturally computes the correct result for any opcode.
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux | dea9989a3f3961faede93752cd81eb5a9514d911, 4c122e8ae14950cf6b59d208fc5160f7c601e746, e52567173ba86dbffb990595fbe60e2e83899372, bffacdb80b93b7b5e96b26fad64cc490a6c7d6c7, 7.0-rc1, 6.12.79, 6.18.20, 6.19.10, 7.0-rc4 |
Downstream vendors/products affected by this vulnerability
| Vendor | Product | Source | Confidence |
|---|---|---|---|
| linux | linux | mitre_affected | 90% |
Updated description with new details, added affected versions, changed severity to CRITICAL, and noted that there is no available exploit.
Initial creation
