• The "branch history injection" hardware vulnerability

    From LWN.net@1337:1/100 to All on Tue Apr 9 20:30:06 2024
    The "branch history injection" hardware vulnerability

    Date:
    Tue, 09 Apr 2024 19:22:50 +0000

    Description:
    The mainline kernel has just received a set of commits mitigating the
    latest x86 hardware vulnerability, known as "branch history injection".
    From this commit : Branch History Injection (BHI) attacks may allow a malicious
    application to influence indirect branch prediction in kernel by
    poisoning the branch history. eIBRS isolates indirect branch
    targets in ring0. The BHB can still influence the choice of
    indirect branch predictor entry, and although branch predictor
    entries are isolated between modes when eIBRS is enabled, the BHB
    itself is not isolated between modes. See this commit for
    documentation on the command-line parameter that controls this mitigation. There are stable kernel releases ( 6.8.5 , 6.6.26 , 6.1.85 ,
    and 5.15.154 )
    in the works that also contain the mitigations.

    ======================================================================
    Link to news story:
    https://lwn.net/Articles/969210/


    --- Mystic BBS v1.12 A47 (Linux/64)
    * Origin: tqwNet UK HUB @ hub.uk.erb.pw (1337:1/100)