sshd broken on arm?

[M. Warner Losh]

In message: <4790D750.4060702 at errno.com>
            Sam Leffler <sam at errno.com> writes:
: John Hay wrote:
: > On Thu, Jan 17, 2008 at 12:58:54PM +0200, John Hay wrote:
: >   
: >> Hi Guys,
: >>
: >> I just did a new build using RELENG_7 for the arm (Avila boards) and then
: >> found that I cannot ssh into them. The sshd crash with a bus error just
: >> after you entered your username and password. My build of mid November
: >> did not do it. Anybody got ideas?
: >>
: >> The last part of "sshd -Dddd" on the arm board looks like this:
: >>
: >> debug1: server_input_channel_req: channel 0 request pty-req reply 0
: >> debug1: session_by_channel: session 0 channel 0
: >> debug1: session_input_channel_req: session 0 req pty-req
: >> debug1: Allocating pty.
: >> debug3: mm_request_send entering: type 25
: >> debug3: monitor_read: checking request 25
: >> debug3: mm_answer_pty entering
: >> debug1: session_new: init
: >> debug1: session_new: session 0
: >> debug3: mm_pty_allocate: waiting for MONITOR_ANS_PTY
: >> debug3: mm_request_receive_expect entering: type 26
: >> debug3: mm_request_receive entering
: >> debug3: mm_request_send entering: type 26
: >> ssh_mm_receive_fd: recvmsg: expected received 1 got 0
: >> debug1: do_cleanup
: >> debug1: PAM: cleanup
: >> Bus error (core dumped)
: >> debug3: PAM: sshpam_thread_cleanup entering
: >>     
: >
: > Ok, I found the problem. It looks like something changed and now the
: > alignment for the char tmp[...] array in monitor_fdpass.c:mm_send_fd
: > and monitor_fdpass.c:mm_receive_fd is different and the arm processors
: > do not like it. Attached is my quick fix.
: >
: > One question that I have is if we should just fix all of these "problems"
: > or should something be changed so that these things are aligned again? In
: > the last month or two I have come across quite a few of these things that
: > used to work on the arm and now do not anymore because of alignment
: > changes.
: >
: > (I have cc'ed des@ because his name pitch up a lot in the openssh cvs logs.
: > :-)
: >   
: 
: This used to work fine so the problem is elsewhere.  Sounds like a 
: toolchain or header change is the root cause.

Or some subtle change in the kernel that isn't using the macro (or is
now and didn't used to be).

John, I don't suppose you'd have time for a binary search?

Warner