The current implementation of the prctl syscall does not issue an IBPB immediately during the syscall. The ib_prctl_set function updates the Thread Information Flags (TIFs) for the task and updates the SPEC_CTRL MSR on the function __speculation_ctrl_update, but the IBPB is only issued on the next schedule, when the TIF bits are checked. This leaves the victim vulnerable to values already injected on the BTB, prior to the prctl syscall. The patch that added the support for the conditional mitigation via prctl (ib_prctl_set) dates back to the kernel 4.9.176.
We recommend upgrading past commit a664ec9158eeddd75121d39c9a0758016097fa96
References
Link | Resource |
---|---|
https://git.kernel.org/tip/a664ec9158eeddd75121d39c9a0758016097fa96 | Mailing List Patch |
https://github.com/google/security-research/security/advisories/GHSA-9x5g-vmxf-4qj8 | Exploit Third Party Advisory |
https://lists.debian.org/debian-lts-announce/2023/05/msg00005.html | Mailing List Third Party Advisory |
https://lists.debian.org/debian-lts-announce/2023/05/msg00006.html | Mailing List Third Party Advisory |
https://security.netapp.com/advisory/ntap-20230714-0001/ | Third Party Advisory |
History
No history.
MITRE Information
Status: PUBLISHED
Assigner: Google
Published: 2023-04-25T22:44:57.262Z
Updated: 2023-04-25T22:44:57.262Z
Reserved: 2023-01-04T10:07:20.469Z
Link: CVE-2023-0045
JSON object: View
NVD Information
Status : Analyzed
Published: 2023-04-25T23:15:09.013
Modified: 2023-08-11T19:53:56.443
Link: CVE-2023-0045
JSON object: View
Redhat Information
No data.
CWE