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Make some minor fixups to bug reporting, etc.

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This commit is contained in:
Justine Tunney 2022-07-11 05:55:17 -07:00
parent 84764ce7b8
commit 3f015b1e51
31 changed files with 244 additions and 134 deletions
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33
libc/runtime/mapstack.c
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@ -16,19 +16,48 @@
│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR │
│ PERFORMANCE OF THIS SOFTWARE. │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/calls/calls.h"
#include "libc/dce.h"
#include "libc/intrin/asan.internal.h"
#include "libc/intrin/asancodes.h"
#include "libc/runtime/memtrack.internal.h"
#include "libc/runtime/runtime.h"
#include "libc/runtime/stack.h"
#include "libc/sysv/consts/map.h"
#include "libc/sysv/consts/prot.h"
static char *_stkbase;
__attribute__((__constructor__)) static void init(void) {
_stkbase = (char *)kFixedmapStart;
}
/**
* Allocates stack.
*
* The size of your returned stack is always GetStackSize().
*
* The bottom 4096 bytes of your stack can't be used, since it's always
* reserved for a read-only guard page. With ASAN it'll be poisoned too.
*
* The top 16 bytes of a stack can't be used due to openbsd:stackbound
* and those bytes are also poisoned under ASAN build modes.
*
* @return stack bottom address on success, or null w/ errrno
*/
void *_mapstack(void) {
return mmap(0, GetStackSize(), PROT_READ | PROT_WRITE,
MAP_STACK | MAP_ANONYMOUS, -1, 0);
char *p;
if ((p = mmap(_stkbase, GetStackSize(), PROT_READ | PROT_WRITE,
MAP_STACK | MAP_ANONYMOUS | MAP_FIXED, -1, 0)) != MAP_FAILED) {
if (IsAsan()) {
__asan_poison(p + GetStackSize() - 16, 16, kAsanStackOverflow);
__asan_poison(p, 4096, kAsanStackOverflow);
}
_stkbase += GetStackSize() * 4;
return p;
} else {
return 0;
}
}
/**