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hardened_malloc
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avoid redundant checks for large realloc

pull/50/head
Daniel Micay 2018-10-06 13:31:16 -04:00
parent eb7ced7781
commit d18b05eaf4
1 changed files with 41 additions and 41 deletions
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6
malloc.c
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@ -847,8 +847,9 @@ EXPORT void *h_realloc(void *old, size_t size) {
size_t old_rounded_size = PAGE_CEILING(old_size); size_t old_rounded_size = PAGE_CEILING(old_size);
size_t rounded_size = PAGE_CEILING(size); size_t rounded_size = PAGE_CEILING(size);
if (size > max_slab_size_class) {
// in-place shrink // in-place shrink
if (size < old_size && size > max_slab_size_class) { if (size < old_size) {
void *new_end = (char *)old + rounded_size; void *new_end = (char *)old + rounded_size;
if (memory_map_fixed(new_end, old_guard_size)) { if (memory_map_fixed(new_end, old_guard_size)) {
return NULL; return NULL;
@ -868,7 +869,6 @@ EXPORT void *h_realloc(void *old, size_t size) {
} }
// in-place growth // in-place growth
if (size > old_size) {
void *guard_end = (char *)old + old_rounded_size + old_guard_size; void *guard_end = (char *)old + old_rounded_size + old_guard_size;
size_t extra = rounded_size - old_rounded_size; size_t extra = rounded_size - old_rounded_size;
if (!memory_remap((char *)old + old_rounded_size, old_guard_size, old_guard_size + extra)) { if (!memory_remap((char *)old + old_rounded_size, old_guard_size, old_guard_size + extra)) {
@ -886,7 +886,6 @@ EXPORT void *h_realloc(void *old, size_t size) {
return old; return old;
} }
} }
}
size_t copy_size = size < old_size ? size : old_size; size_t copy_size = size < old_size ? size : old_size;
if (copy_size >= mremap_threshold) { if (copy_size >= mremap_threshold) {
@ -913,6 +912,7 @@ EXPORT void *h_realloc(void *old, size_t size) {
return new; return new;
} }
} }
}
void *new = allocate(size); void *new = allocate(size);
if (new == NULL) { if (new == NULL) {