SIGCLD issues with dropbear server on IRIX 6.5.x

[Kazuo Kuroi]

Hello,

I've recently compiled dropbear 2019-78 as most people here are aware 
from my mailing list messages. I am updating that a build with GCC was 
successful, but there appears to be a problem with how dropbear is 
handing SIGCLD on IRIX, causing forked processes to hang.

https://pastebin.com/04v74Yt5

Here is the output of attaching par (IRIX's version of truss) to the 
PID, then trying to logout of the session, which hangs the ssh client 
and that particular process of the server.

I have to issue a sigkill to the process to stop it on the server side.

Additionally, I'd like to report a small patch needed to fix IOV_MAX for 
IRIX in netio.c:

         #ifndef IOV_MAX
                 #if defined(__CYGWIN__) && !defined(UIO_MAXIOV)
                 #define IOV_MAX 1024
                 #elif defined(__sgi)
                 #define IOV_MAX 512
                 #else
                 #define IOV_MAX UIO_MAXIOV

The elif and __sgi macro had to be added. This will fix it for both 
mipspro and gcc. I've also confirmed with the libtom upstream that the 
version of libtomcrypt that I reported in my earlier messages isn't 
exhibiting that bug; so if someone could give insight how to fix this: 
https://pastebin.com/gnGxGmZH then a build with MIPSPro may finally be 
possible.

Thank you very much.


- Kazuo Kuroi