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bsdinstall: Harden reading the kernel message buffer
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Authored by jlduran on Oct 17 2025, 4:40 PM.
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Details

Reviewers
emaste
Group Reviewers
security
Summary

When choosing the option to harden reading the kernel message buffer by
an unprivileged user in bsdinstall, access to the kernel message buffer
is restricted via its sysctl (security.bsd.unprivileged_read_msgbuf=0).

In order for this setting to be effective, access to this data via
system logs must also be restricted. Add the necessary hooks to
restrict access to the log files:

  • /var/log/messages
  • /var/run/dmesg.boot ($dmesg_file)

PR: 272552

Diff Detail

Repository
rG FreeBSD src repository
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Build Status
Buildable 67875
Build 64758: arc lint + arc unit