krun: use of invalid errno

[eriksjolund]

1. To get some more insight of the crun source code I ran the command

    git grep -20 " errno" src
   

   There were quite many search results, but I tried to go through the result to find some suspicious uses of errno. I saw this line that looked a bit suspicious:
   

   crun/src/libcrun/handlers/krun.c

   Line 710 in 46cedc0

   return crun_make_error (err, errno, "start passt");

   
   in case this code returned -1
   

   crun/src/libcrun/handlers/krun.c

   Lines 636 to 638 in 46cedc0

   	waitpid (pid, &status, 0);
   	if (! (WIFEXITED (status)) || WEXITSTATUS (status) != 0)
   	return -1;

2. To get a second opinion, I typed the following in claude web interface claude.ai (claude opus 5)

   Could you check if errno at this line
   https://github.com/containers/crun/blob/46cedc0c4a7342a7bd76f36b7fd7ab01869074e4/src/libcrun/handlers/krun.c#L710
   has been set by a failure beforehand?
   

   As usual claude responded with a lot of text, but in the output it looked like claude concluded that it was invalid use of errno.