Re: 2nd Linux kernel patch to remove stack exec

David S. Miller (davem@jenolan.rutgers.edu)
Mon, 14 Apr 1997 05:26:26 -0400

Perhaps some people don't understand, every single Linux binary on
every platform supported that I know of, needs an executable stack to
have signals work at all. When you type 'ls' a signal can get
delivered to your shell to notify it that the child has exited. Just
about every program needs signals that is of any use.

If you make this change to take away execute permission on the users
stack, all existing Linux binaries would break.

Barring the transition nightmares, at a bare minimum someone would
need to find a new way to handle multi-threaded signal dispatch in
clone() processes that did not stick instructions on the signal stack
like the current implementations do on every architecture. And even
then, it would take a lot of effort and time to get from that point to
it actually going into the kernel.

Let this thread die a painless quick death...

---------------------------------------------////
Yow! 11.26 MB/s remote host TCP bandwidth & ////
199 usec remote TCP latency over 100Mb/s ////
ethernet. Beat that! ////
-----------------------------------------////__________ o
David S. Miller, davem@caip.rutgers.edu /_____________/ / // /_/ ><