Re: git: 8646d65b4533 - main - hastd: Fix crash on empty message

On Thu, Sep 03, 2026 at 07:59:15AM -0500, Dag-Erling Smørgrav wrote:
> The branch main has been updated by des:
> 
> URL: https://cgit.FreeBSD.org/src/commit/?id=8646d65b45339642d4aab1de35a2bc79fc45f09e
> 
> commit 8646d65b45339642d4aab1de35a2bc79fc45f09e
> Author:     Glen Barber <gjb@FreeBSD.org>
> AuthorDate: 2026-09-03 07:51:28 +0000
> Commit:     Dag-Erling Smørgrav <des@FreeBSD.org>
> CommitDate: 2026-09-03 07:58:54 +0000
> 
>     hastd: Fix crash on empty message
>     
>     A HAST message can be empty, in which case ebuf_add_tail() does nothing
>     and ebuf_data() returns NULL because the size of the ebuf is zero, but
>     hast_proto_recv_hdr() asserts that the return value is not NULL,
>     resulting in an immediate crash if hastctl or hastd receive an empty
>     message.  This is trivially reproducable by running `hastctl status` or
>     `hastctl role init` (as the rc script does prior to stopping hastd).
>     
>     To avoid this, don't try to grow the ebuf or receive additional data
>     if the header size is zero.
>     
>     PR:             298085
>     MFC after:      3 days
>     Reviewed by:    kevans, gjb
>     Differential Revision:  https://reviews.freebsd.org/D59306
> ---
>  sbin/hastd/hast_proto.c | 14 ++++++++------
>  1 file changed, 8 insertions(+), 6 deletions(-)

Thank you!

Glen