Skip to content

Check the links before unlinking a huge block #23568

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
jvoisin wants to merge 1 commit into
base: master
Choose a base branch
from
+21 −4
Open

Check the links before unlinking a huge block #23568

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
25 changes: 21 additions & 4 deletions Zend/zend_alloc.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -356,6 +356,7 @@ struct _zend_mm_huge_list {
void *ptr;
size_t size;
zend_mm_huge_list *next;
zend_mm_huge_list *prev;
#if ZEND_DEBUG
zend_mm_debug_info dbg;
#endif
Expand Down Expand Up @@ -1931,6 +1932,10 @@ static void zend_mm_add_huge_block(zend_mm_heap *heap, void *ptr, size_t size ZE
list->ptr = ptr;
list->size = size;
list->next = heap->huge_list;
list->prev = NULL;
if (heap->huge_list) {
heap->huge_list->prev = list;
}
#if ZEND_DEBUG
list->dbg.size = dbg_size;
list->dbg.filename = __zend_filename;
Expand All @@ -1943,22 +1948,28 @@ static void zend_mm_add_huge_block(zend_mm_heap *heap, void *ptr, size_t size ZE

static size_t zend_mm_del_huge_block(zend_mm_heap *heap, void *ptr ZEND_FILE_LINE_DC ZEND_FILE_LINE_ORIG_DC)
{
zend_mm_huge_list *prev = NULL;
zend_mm_huge_list *list = heap->huge_list;
while (list != NULL) {
if (list->ptr == ptr) {
size_t size;

if (prev) {
prev->next = list->next;
/* Unlinking writes through these, so make sure they still point back
* at this block before trusting them. */
ZEND_MM_CHECK(list->prev ? list->prev->next == list : heap->huge_list == list, "zend_mm_heap corrupted");
ZEND_MM_CHECK(!list->next || list->next->prev == list, "zend_mm_heap corrupted");

if (list->prev) {
list->prev->next = list->next;
} else {
heap->huge_list = list->next;
}
if (list->next) {
list->next->prev = list->prev;
}
size = list->size;
zend_mm_free_heap(heap, list ZEND_FILE_LINE_RELAY_CC ZEND_FILE_LINE_ORIG_RELAY_CC);
return size;
}
prev = list;
list = list->next;
}
ZEND_MM_CHECK(0, "zend_mm_heap corrupted");
Expand Down Expand Up @@ -2388,6 +2399,9 @@ static zend_long zend_mm_find_leaks_huge(zend_mm_heap *heap, zend_mm_huge_list *
while (p) {
if (p->dbg.filename == list->dbg.filename && p->dbg.lineno == list->dbg.lineno) {
prev->next = p->next;
if (p->next) {
p->next->prev = prev;
}
zend_mm_chunk_free(heap, p->ptr, p->size);
zend_mm_free_heap(heap, p, NULL, 0, NULL, 0);
count++;
Expand Down Expand Up @@ -2430,6 +2444,9 @@ static void zend_mm_check_leaks(zend_mm_heap *heap)
}

heap->huge_list = list = list->next;
if (list) {
list->prev = NULL;
}
zend_mm_chunk_free(heap, q->ptr, q->size);
zend_mm_free_heap(heap, q, NULL, 0, NULL, 0);
}
Expand Down
Loading