rc: avoid calling free inside SIGCHLD handler

`free` is not async-signal-safe and calling it inside a signal handler
can have bad effects, as reported in the musl ML:
https://www.openwall.com/lists/musl/2023/01/23/1

the solution:

- keep track of weather remove_pid() is being called from inside a
  signal handler or not.
- if it's inside a signal handler then DO NOT call free - instead put
  that pointer into a "to be freed later" list.
- if it's not inside a signal handler then take the "to be freed later"
  list and free anything in it.

Bug: https://github.com/OpenRC/openrc/issues/589
Reported-by: Dominique MARTINET <dominique.martinet@atmark-techno.com>

0 files changed, 0 insertions, 0 deletions