Page MenuHomeFreeBSD
Differential D58822

db/hash: Harden hash(3) database code
ClosedPublic
Actions

Authored by bnovkov on Aug 13 2026, 11:12 AM.
Tags
None
Referenced Files
Unknown Object (File)
Sat, Sep 19, 10:31 PM
Unknown Object (File)
Thu, Sep 17, 4:38 AM
Unknown Object (File)
Tue, Sep 15, 11:06 PM
Unknown Object (File)
Tue, Sep 15, 1:41 AM
Unknown Object (File)
Sat, Sep 12, 8:08 AM
Unknown Object (File)
Sat, Sep 12, 7:54 AM
Unknown Object (File)
Fri, Sep 11, 5:37 AM
Unknown Object (File)
Fri, Sep 11, 4:14 AM
View All 56 Files
Subscribers
imp
kevans

Details

Reviewers
kevans
Group Reviewers
Klara
Commits
rG7f5f07b139a5: db/hash: Harden hash(3) database code
Summary

The hash(3) database code does not validate the on-disk database header,
leaving it open to several OOB read and write vulnerabilities.

This change adds basic header validation and array bounds checking to
parts of the hash(3) code that can be manipulated by messing with the
database header.

Sponsored by: Klara, Inc.
MFC after: 1 month

Diff Detail

Repository
rG FreeBSD src repository
Lint
Lint Skipped
Unit
Tests Skipped
Build Status
Buildable 76922
Build 73805: arc lint + arc unit

Event Timeline

bnovkov created this revision.Aug 13 2026, 11:12 AM
Herald added a subscriber: imp. · View Herald TranscriptAug 13 2026, 11:12 AM
bnovkov requested review of this revision.Aug 13 2026, 11:12 AM
Harbormaster completed remote builds in B75559: Diff 183976.Aug 13 2026, 11:12 AM
kevans added a subscriber: kevans.Aug 13 2026, 1:51 PM
kevans added inline comments.
lib/libc/db/hash/hash.c
161

This is also signed, are negative values not an issue?

bnovkov updated this revision to Diff 184039.Aug 14 2026, 8:45 AM

Address @kevans 's comment

Harbormaster completed remote builds in B75584: Diff 184039.Aug 14 2026, 8:45 AM
bnovkov marked an inline comment as done.Aug 14 2026, 8:46 AM
bnovkov added inline comments.
lib/libc/db/hash/hash.c
161

Thanks for catching this, negative values here are an issue.

bnovkov updated this revision to Diff 185328.Fri, Aug 28, 10:12 AM
bnovkov marked an inline comment as done.

Propagate error from bounds checking instead of aborting

Harbormaster completed remote builds in B76275: Diff 185328.Fri, Aug 28, 10:13 AM
bnovkov updated this revision to Diff 186766.Tue, Sep 15, 2:02 PM

Hoist 'splitnum' check

Harbormaster completed remote builds in B76922: Diff 186766.Tue, Sep 15, 2:02 PM
kevans accepted this revision.Thu, Sep 17, 4:29 PM
This revision is now accepted and ready to land.Thu, Sep 17, 4:29 PM
Closed by commit rG7f5f07b139a5: db/hash: Harden hash(3) database code (authored by bnovkov). · Explain WhyFri, Sep 18, 10:31 AM
This revision was automatically updated to reflect the committed changes.
bnovkov added a commit: rG7f5f07b139a5: db/hash: Harden hash(3) database code.

Revision Contents
Changeset List

PathSize
lib/
libc/
db/
hash/
47 lines
16 lines
16 lines
tests/
db/
3 lines
227 lines

Diff 186766

View Options

lib/libc/db/hash/hash.c

Loading...
View Options

lib/libc/db/hash/hash_buf.c

Loading...
View Options

lib/libc/db/hash/hash_page.c

Loading...
View Options

lib/libc/tests/db/Makefile

Loading...
View Options

lib/libc/tests/db/db_hash_tamper_test.c

Loading...