[Bug 255507] traceroute6 generates wrong UDP checksum

[b***@freebsd.org]

https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=255507

Mark Linimon <***@FreeBSD.org> changed:

What |Removed |Added
----------------------------------------------------------------------------
Assignee|***@FreeBSD.org |***@FreeBSD.org

[b***@freebsd.org]

https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=255507

Zhenlei Huang <***@gmail.com> changed:

What |Removed |Added
----------------------------------------------------------------------------
See Also| |https://reviews.freebsd.org
| |/D30042

--- Comment #1 from Zhenlei Huang <***@gmail.com> ---
I can confirm the regression was introduced in review D25604 .

Proposed patch https://reviews.freebsd.org/D30042

[b***@freebsd.org]

https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=255507

Zhenlei Huang <***@gmail.com> changed:

What |Removed |Added
----------------------------------------------------------------------------
See Also|https://reviews.freebsd.org |https://reviews.freebsd.org
|/D30042 |/D25604
URL| |https://reviews.freebsd.org
| |/D30042

[b***@freebsd.org]

https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=255507

Ed Maste <***@freebsd.org> changed:

What |Removed |Added
----------------------------------------------------------------------------
CC| |***@freebsd.org
Status|New |In Progress

[b***@freebsd.org]

https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=255507

--- Comment #2 from commit-***@FreeBSD.org ---
A commit in branch main references this bug:

URL:
https://cgit.FreeBSD.org/src/commit/?id=1d712c05370dca8cbf81d1ecd9acd606fdcacaf4

commit 1d712c05370dca8cbf81d1ecd9acd606fdcacaf4
Author: Zhenlei Huang <***@gmail.com>
AuthorDate: 2021-05-03 16:46:19 +0000
Commit: Mark Johnston <***@FreeBSD.org>
CommitDate: 2021-05-03 17:24:30 +0000

traceroute6: Properly calculate UDP checksum

The revision D25604 capsicumize traceroute6. For UDP the send socket was
changed from SOCK_DGRAM to SOCK_RAW and thus the UDP checksum need be
calculated by application itself other than the kernel.

outpacket is filled with zeros by line 707, thus the first round the UDP
checksum is correct. But subsequent rounds outudp->uh_sum will be left
with garbage.

PR: 255507
Reviewed by: ae, markj, tuexen
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D30042

usr.sbin/traceroute6/traceroute6.c | 1 +
1 file changed, 1 insertion(+)

[b***@freebsd.org]

https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=255507

--- Comment #3 from commit-***@FreeBSD.org ---
A commit in branch stable/13 references this bug:

URL:
https://cgit.FreeBSD.org/src/commit/?id=e183dd501caf03751c96c7c0683ccc3a6c0cd27d

commit e183dd501caf03751c96c7c0683ccc3a6c0cd27d
Author: Zhenlei Huang <***@gmail.com>
AuthorDate: 2021-05-03 16:46:19 +0000
Commit: Mark Johnston <***@FreeBSD.org>
CommitDate: 2021-05-06 12:59:19 +0000

traceroute6: Properly calculate UDP checksum

The revision D25604 capsicumize traceroute6. For UDP the send socket was
changed from SOCK_DGRAM to SOCK_RAW and thus the UDP checksum need be
calculated by application itself other than the kernel.

outpacket is filled with zeros by line 707, thus the first round the UDP
checksum is correct. But subsequent rounds outudp->uh_sum will be left
with garbage.

PR: 255507
Reviewed by: ae, markj, tuexen
Differential Revision: https://reviews.freebsd.org/D30042

(cherry picked from commit 1d712c05370dca8cbf81d1ecd9acd606fdcacaf4)

usr.sbin/traceroute6/traceroute6.c | 1 +
1 file changed, 1 insertion(+)

[b***@freebsd.org]

https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=255507

Mark Johnston <***@FreeBSD.org> changed:

What |Removed |Added
----------------------------------------------------------------------------
Status|In Progress |Closed
Resolution|--- |FIXED

--- Comment #4 from Mark Johnston <***@FreeBSD.org> ---
Thanks for the report and patch.