sigaltstack: enforce dynamic MINSIGSTKSZ limit

commit 996b6154b2 added support for
querying the dynamic limit but did not enforce it in sigaltstack. the
kernel also does not seem to reliably enforce it, or at least does not
necessarily enforce the same limit exposed to userspace, so it needs
to be enforced here.
This commit is contained in:
Rich Felker 2024-08-31 12:25:44 -04:00
parent 572a2e2eb9
commit 300a1f5390

View File

@ -1,11 +1,13 @@
#include <signal.h>
#include <errno.h>
#include <unistd.h>
#include "syscall.h"
int sigaltstack(const stack_t *restrict ss, stack_t *restrict old)
{
if (ss) {
if (!(ss->ss_flags & SS_DISABLE) && ss->ss_size < MINSIGSTKSZ) {
size_t min = sysconf(_SC_MINSIGSTKSZ);
if (!(ss->ss_flags & SS_DISABLE) && ss->ss_size < min) {
errno = ENOMEM;
return -1;
}