From 1c514847996fba21af276b96d0d748b1ce8f3772 Mon Sep 17 00:00:00 2001 From: Daan Date: Tue, 3 Jun 2025 11:36:07 -0700 Subject: [PATCH 1/3] fix missing csize assignment in _mi_os_free_ex --- src/os.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/os.c b/src/os.c index d134feba..dee263bc 100644 --- a/src/os.c +++ b/src/os.c @@ -181,7 +181,7 @@ static void mi_os_prim_free(void* addr, size_t size, size_t commit_size) { void _mi_os_free_ex(void* addr, size_t size, bool still_committed, mi_memid_t memid) { if (mi_memkind_is_os(memid.memkind)) { size_t csize = memid.mem.os.size; - if (csize==0) { _mi_os_good_alloc_size(size); } + if (csize==0) { csize = _mi_os_good_alloc_size(size); } size_t commit_size = (still_committed ? csize : 0); void* base = addr; // different base? (due to alignment) From 60f7e6a6a846dcf9ebe2b29530f0b309d4fd1dd2 Mon Sep 17 00:00:00 2001 From: Daan Date: Tue, 3 Jun 2025 12:20:02 -0700 Subject: [PATCH 2/3] check all os_commit calls and return NULL on failure --- include/mimalloc/internal.h | 6 +++--- src/os.c | 5 ++++- src/page.c | 26 +++++++++++++++++--------- src/segment.c | 4 +++- 4 files changed, 27 insertions(+), 14 deletions(-) diff --git a/include/mimalloc/internal.h b/include/mimalloc/internal.h index 2e770943..e1052787 100644 --- a/include/mimalloc/internal.h +++ b/include/mimalloc/internal.h @@ -126,13 +126,13 @@ bool _mi_os_has_overcommit(void); bool _mi_os_has_virtual_reserve(void); bool _mi_os_reset(void* addr, size_t size); -bool _mi_os_commit(void* p, size_t size, bool* is_zero); -bool _mi_os_commit_ex(void* addr, size_t size, bool* is_zero, size_t stat_size); bool _mi_os_decommit(void* addr, size_t size); -bool _mi_os_protect(void* addr, size_t size); bool _mi_os_unprotect(void* addr, size_t size); bool _mi_os_purge(void* p, size_t size); bool _mi_os_purge_ex(void* p, size_t size, bool allow_reset, size_t stat_size); +mi_decl_nodiscard bool _mi_os_commit(void* p, size_t size, bool* is_zero); +mi_decl_nodiscard bool _mi_os_commit_ex(void* addr, size_t size, bool* is_zero, size_t stat_size); +mi_decl_nodiscard bool _mi_os_protect(void* addr, size_t size); void* _mi_os_alloc_aligned(size_t size, size_t alignment, bool commit, bool allow_large, mi_memid_t* memid); void* _mi_os_alloc_aligned_at_offset(size_t size, size_t alignment, size_t align_offset, bool commit, bool allow_large, mi_memid_t* memid); diff --git a/src/os.c b/src/os.c index dee263bc..c720c8ad 100644 --- a/src/os.c +++ b/src/os.c @@ -300,7 +300,10 @@ static void* mi_os_prim_alloc_aligned(size_t size, size_t alignment, bool commit // explicitly commit only the aligned part if (commit) { - _mi_os_commit(p, size, NULL); + if (!_mi_os_commit(p, size, NULL)) { + mi_os_prim_free(p, over_size, 0); + return NULL; + } } } else { // mmap can free inside an allocation diff --git a/src/page.c b/src/page.c index 89acb409..b34ee414 100644 --- a/src/page.c +++ b/src/page.c @@ -37,7 +37,7 @@ static inline mi_block_t* mi_page_block_at(const mi_page_t* page, void* page_sta } static void mi_page_init(mi_heap_t* heap, mi_page_t* page, size_t size, mi_tld_t* tld); -static void mi_page_extend_free(mi_heap_t* heap, mi_page_t* page, mi_tld_t* tld); +static bool mi_page_extend_free(mi_heap_t* heap, mi_page_t* page, mi_tld_t* tld); #if (MI_DEBUG>=3) static size_t mi_page_list_count(mi_page_t* page, mi_block_t* head) { @@ -630,14 +630,14 @@ static mi_decl_noinline void mi_page_free_list_extend( mi_page_t* const page, co // Note: we also experimented with "bump" allocation on the first // allocations but this did not speed up any benchmark (due to an // extra test in malloc? or cache effects?) -static void mi_page_extend_free(mi_heap_t* heap, mi_page_t* page, mi_tld_t* tld) { +static bool mi_page_extend_free(mi_heap_t* heap, mi_page_t* page, mi_tld_t* tld) { mi_assert_expensive(mi_page_is_valid_init(page)); #if (MI_SECURE<=2) mi_assert(page->free == NULL); mi_assert(page->local_free == NULL); - if (page->free != NULL) return; + if (page->free != NULL) return true; #endif - if (page->capacity >= page->reserved) return; + if (page->capacity >= page->reserved) return true; size_t page_size; //uint8_t* page_start = @@ -673,6 +673,7 @@ static void mi_page_extend_free(mi_heap_t* heap, mi_page_t* page, mi_tld_t* tld) page->capacity += (uint16_t)extend; mi_stat_increase(tld->stats.page_committed, extend * bsize); mi_assert_expensive(mi_page_is_valid_init(page)); + return true; } // Initialize a fresh page @@ -724,8 +725,10 @@ static void mi_page_init(mi_heap_t* heap, mi_page_t* page, size_t block_size, mi mi_assert_expensive(mi_page_is_valid_init(page)); // initialize an initial free list - mi_page_extend_free(heap,page,tld); - mi_assert(mi_page_immediate_available(page)); + if (mi_page_extend_free(heap,page,tld)) { + mi_assert(mi_page_immediate_available(page)); + } + return; } @@ -817,9 +820,14 @@ static mi_page_t* mi_page_queue_find_free_ex(mi_heap_t* heap, mi_page_queue_t* p if (page_candidate != NULL) { page = page_candidate; } - if (page != NULL && !mi_page_immediate_available(page)) { - mi_assert_internal(mi_page_is_expandable(page)); - mi_page_extend_free(heap, page, heap->tld); + if (page != NULL) { + if (!mi_page_immediate_available(page)) { + mi_assert_internal(mi_page_is_expandable(page)); + if (!mi_page_extend_free(heap, page, heap->tld)) { + page = NULL; // failed to extend + } + } + mi_assert_internal(page == NULL || mi_page_immediate_available(page)); } if (page == NULL) { diff --git a/src/segment.c b/src/segment.c index 708ddd00..1813a1fc 100644 --- a/src/segment.c +++ b/src/segment.c @@ -182,7 +182,9 @@ static bool mi_page_not_in_queue(const mi_page_t* page, mi_segments_tld_t* tld) static void mi_segment_protect_range(void* p, size_t size, bool protect) { if (protect) { - _mi_os_protect(p, size); + if (!_mi_os_protect(p, size)) { + _mi_error_message(EFAULT,"unable to protect segment memory at %p\n", p); + } } else { _mi_os_unprotect(p, size); From a0072ba7c335e38bcd20f854692930fcb1d00d5a Mon Sep 17 00:00:00 2001 From: Daan Date: Tue, 3 Jun 2025 15:07:15 -0700 Subject: [PATCH 3/3] fix base address if commit fails on aligned overallocation --- src/os.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/os.c b/src/os.c index c720c8ad..580b8af0 100644 --- a/src/os.c +++ b/src/os.c @@ -301,7 +301,7 @@ static void* mi_os_prim_alloc_aligned(size_t size, size_t alignment, bool commit // explicitly commit only the aligned part if (commit) { if (!_mi_os_commit(p, size, NULL)) { - mi_os_prim_free(p, over_size, 0); + mi_os_prim_free(*base, over_size, 0); return NULL; } }