4 ms·
In general yes, but the code in this case appears to be supplying its own version of exit, that just does a SYSCALL instruction. The SYSCALL instruction doesn't
by to3m 11y ago
In general yes, but the code in this case appears to be supplying its own version of exit, that just does a SYSCALL instruction. The SYSCALL instruction doesn't need a stack.
- 0x0 11y agoIs there no risk of an interrupt or a signal happening in between un-mmap'ing and calling exit, that would cause stack pushes?
- Amanieu 11y agoThat is a risk, which is why you need to block all signals using the sigprocmask syscall before unmapping your stack.
- geofft 11y agoOr you just don't have signal-handling functions. Signals only touch the stack if you handle them via functions. The default signal dispositions all either kill the process or do nothing, so they don't touch the stack.