use physical memory in kib to avoid overflow of size_t (issue microsoft#1010)

daanx · daanx · commit 0c8069adab0f · 2025-02-11T09:18:23.000-08:00
diff --git a/src/prim/unix/prim.c b/src/prim/unix/prim.c
@@ -142,8 +142,9 @@ void _mi_prim_mem_init( mi_os_mem_config_t* config )
     config->alloc_granularity = (size_t)psize;
     #if defined(_SC_PHYS_PAGES)
     long pphys = sysconf(_SC_PHYS_PAGES);
-    if (pphys > 0 && (size_t)pphys < (SIZE_MAX/(size_t)psize)) {
-      config->physical_memory_in_kib = (size_t)pphys * ((size_t)psize / MI_KiB);
+    const size_t psize_in_kib = (size_t)psize / MI_KiB;
+    if (psize_in_kib > 0 && pphys > 0 && (size_t)pphys <= (SIZE_MAX/psize_in_kib)) {
+      config->physical_memory_in_kib = (size_t)pphys * psize_in_kib;
     }
     #endif
   }
diff --git a/src/prim/windows/prim.c b/src/prim/windows/prim.c
@@ -154,7 +154,7 @@ void _mi_prim_mem_init( mi_os_mem_config_t* config )
     if (pGetPhysicallyInstalledSystemMemory != NULL) {
       ULONGLONG memInKiB = 0;
       if ((*pGetPhysicallyInstalledSystemMemory)(&memInKiB)) {
-        if (memInKiB > 0 && memInKiB < (SIZE_MAX / MI_KiB)) {
+        if (memInKiB > 0 && memInKiB <= SIZE_MAX) {
           config->physical_memory_in_kib = memInKiB;
         }
       }

Original file line number	Diff line number	Diff line change
`@@ -142,8 +142,9 @@ void _mi_prim_mem_init( mi_os_mem_config_t* config )`
`142`	`142`	`config->alloc_granularity = (size_t)psize;`
`143`	`143`	`#if defined(_SC_PHYS_PAGES)`
`144`	`144`	`long pphys = sysconf(_SC_PHYS_PAGES);`
`145`		`- if (pphys > 0 && (size_t)pphys < (SIZE_MAX/(size_t)psize)) {`
`146`		`- config->physical_memory_in_kib = (size_t)pphys * ((size_t)psize / MI_KiB);`
	`145`	`+ const size_t psize_in_kib = (size_t)psize / MI_KiB;`
	`146`	`+ if (psize_in_kib > 0 && pphys > 0 && (size_t)pphys <= (SIZE_MAX/psize_in_kib)) {`
	`147`	`+ config->physical_memory_in_kib = (size_t)pphys * psize_in_kib;`
`147`	`148`	`}`
`148`	`149`	`#endif`
`149`	`150`	`}`
Original file line number	Diff line number	Diff line change
`@@ -154,7 +154,7 @@ void _mi_prim_mem_init( mi_os_mem_config_t* config )`
`154`	`154`	`if (pGetPhysicallyInstalledSystemMemory != NULL) {`
`155`	`155`	`ULONGLONG memInKiB = 0;`
`156`	`156`	`if ((*pGetPhysicallyInstalledSystemMemory)(&memInKiB)) {`
`157`		`- if (memInKiB > 0 && memInKiB < (SIZE_MAX / MI_KiB)) {`
	`157`	`+ if (memInKiB > 0 && memInKiB <= SIZE_MAX) {`
`158`	`158`	`config->physical_memory_in_kib = memInKiB;`
`159`	`159`	`}`
`160`	`160`	`}`