fix valid pointer check for low addresses (#issue 1087)

This commit is contained in:
daanx 2025-05-21 16:04:13 -07:00
parent c2621f8fbe
commit 4161152d17

View file

@ -200,7 +200,8 @@ bool _mi_page_map_init(void) {
mi_assert(mi_page_map_count <= MI_PAGE_MAP_COUNT);
const size_t os_page_size = _mi_os_page_size();
const size_t page_map_size = _mi_align_up( mi_page_map_count * sizeof(mi_page_t**), os_page_size);
const size_t reserve_size = page_map_size + os_page_size;
const size_t submap_size = MI_PAGE_MAP_SUB_SIZE;
const size_t reserve_size = page_map_size + submap_size;
const bool commit = page_map_size <= 64*MI_KiB ||
mi_option_is_enabled(mi_option_pagemap_commit) || _mi_os_has_overcommit();
_mi_page_map = (_Atomic(mi_page_t**)*)_mi_os_alloc_aligned(reserve_size, 1, commit, true /* allow large */, &mi_page_map_memid);
@ -220,10 +221,10 @@ bool _mi_page_map_init(void) {
}
_mi_page_map[0] = (mi_page_t**)((uint8_t*)_mi_page_map + page_map_size); // we reserved a submap part at the end already
if (!mi_page_map_memid.initially_committed) {
_mi_os_commit(_mi_page_map[0], os_page_size, NULL); // only first OS page
_mi_os_commit(_mi_page_map[0], submap_size, NULL); // commit full submap (issue #1087)
}
if (!mi_page_map_memid.initially_zero) { // initialize first addresses with NULL
_mi_memzero_aligned(_mi_page_map[0], os_page_size);
if (!mi_page_map_memid.initially_zero) { // initialize low addresses with NULL
_mi_memzero_aligned(_mi_page_map[0], submap_size);
}
mi_assert_internal(_mi_ptr_page(NULL)==NULL);
@ -233,12 +234,12 @@ bool _mi_page_map_init(void) {
void _mi_page_map_unsafe_destroy(void) {
mi_assert_internal(_mi_page_map != NULL);
if (_mi_page_map == NULL) return;
for (size_t idx = 1; idx < mi_page_map_count; idx++) { // skip entry 0
for (size_t idx = 1; idx < mi_page_map_count; idx++) { // skip entry 0 (as we allocate that submap at the end of the page_map)
// free all sub-maps
if (mi_page_map_is_committed(idx, NULL)) {
mi_page_t** sub = _mi_page_map_at(idx);
if (sub != NULL) {
mi_memid_t memid = _mi_memid_create_os(sub, MI_PAGE_MAP_SUB_COUNT * sizeof(mi_page_t*), true, false, false);
mi_memid_t memid = _mi_memid_create_os(sub, MI_PAGE_MAP_SUB_SIZE, true, false, false);
_mi_os_free(memid.mem.os.base, memid.mem.os.size, memid);
mi_atomic_store_ptr_release(mi_page_t*, &_mi_page_map[idx], NULL);
}
@ -279,7 +280,7 @@ static mi_page_t** mi_page_map_ensure_at(size_t idx) {
// sub map not yet allocated, alloc now
mi_memid_t memid;
mi_page_t** expect = sub;
const size_t submap_size = MI_PAGE_MAP_SUB_COUNT * sizeof(mi_page_t*);
const size_t submap_size = MI_PAGE_MAP_SUB_SIZE;
sub = (mi_page_t**)_mi_os_alloc(submap_size, &memid);
if (sub == NULL) {
_mi_error_message(EFAULT, "internal error: unable to extend the page map\n");