libutil: avoid an out-of-bounds read in trimdomain(3)
ClosedPublic
Actions

Authored by kevans on Jan 9 2026, 5:00 PM.

Details

Reviewers

brooks
jrtc27
olce
des

Group Reviewers

Klara

Commits

rGf268f95955f5: libutil: avoid an out-of-bounds read in trimdomain(3)

Summary

memchr(3) will happily believe we've passed in a valid object, but
hostsize could easily exceed the bounds of fullhost. Clamp it down to
the string size to be safe and avoid UB.

Diff Detail

Repository

rG FreeBSD src repository

Lint

Lint Skipped

Unit

Tests Skipped

Build Status

Buildable 69766
Build 66649: arc lint + arc unit

Event Timeline

kevans created this revision.Jan 9 2026, 5:00 PM

Herald added a reviewer: olce. · View Herald TranscriptJan 9 2026, 5:00 PM

Herald added a subscriber: imp. · View Herald Transcript

kevans requested review of this revision.Jan 9 2026, 5:00 PM

Harbormaster completed remote builds in B69766: Diff 169405.Jan 9 2026, 5:00 PM

kevans added a parent revision: D54622: libutil: take a size_t in trimdomain().Jan 9 2026, 5:00 PM

des accepted this revision.Feb 17 2026, 5:02 PM

This revision is now accepted and ready to land.Feb 17 2026, 5:02 PM

Closed by commit rGf268f95955f5: libutil: avoid an out-of-bounds read in trimdomain(3) (authored by kevans). · Explain WhyMar 3 2026, 10:51 PM

This revision was automatically updated to reflect the committed changes.

kevans added a commit: rGf268f95955f5: libutil: avoid an out-of-bounds read in trimdomain(3).

Revision Contents
Changeset List

Path

Size

lib/

libutil/

tests/

trimdomain_test.c

4 lines

trimdomain.c

6 lines

Diff 169405

View Options

lib/libutil/tests/trimdomain_test.c