Re: [PATCH 1/1] tty: set_termios/set_termiox should not return -EINTR

[Jiri Slaby <jslaby@suse.cz>]

On 01/29/2013 08:07 PM, Oleg Nesterov wrote:
> See https://bugzilla.redhat.com/show_bug.cgi?id=904907
> read command causes bash to abort with double free or corruption (out).
> 
> A simple test-case from Roman:
> 
> 	// Compile the reproducer and send sigchld ti that process.
> 	// EINTR occurs even if SA_RESTART flag is set.
> 
> 	void handler(int sig)
> 	{
> 	}
> 
> 	main()
> 	{
> 	  struct sigaction act;
> 	  act.sa_handler = handler;
> 	  act.sa_flags = SA_RESTART;
> 	  sigaction (SIGCHLD, &act, 0);
> 	  struct termio ttp;
> 	  ioctl(0, TCGETA, &ttp);
> 	  while(1)
> 	  {
> 	    if (ioctl(0, TCSETAW, ttp) < 0)
> 	      {
> 		if (errno == EINTR)
> 		{
> 		  fprintf(stderr, "BUG!"); return(1);
> 		}
> 	      }
> 	  }
> 	}
> 
> Change set_termios/set_termiox to return -ERESTARTSYS to fix this
> particular problem.

This looks reasonable. However given the link above says:
 You are not authorized to access bug #904907.
the description above is poor. What problem exactly does this fix? Why
this should go to stable at all?

-- 
js
suse labs