fix thread data leak; issue #748

daanx · daanx · commit d7a72c491294 · 2023-05-19T09:12:46.000-07:00
diff --git a/src/init.c b/src/init.c
@@ -175,9 +175,9 @@ mi_heap_t* _mi_heap_main_get(void) {
 
 // note: in x64 in release build `sizeof(mi_thread_data_t)` is under 4KiB (= OS page size).
 typedef struct mi_thread_data_s {
-  mi_heap_t  heap;  // must come first due to cast in `_mi_heap_done`
+  mi_heap_t  heap;   // must come first due to cast in `_mi_heap_done`
   mi_tld_t   tld;
-  mi_memid_t memid;
+  mi_memid_t memid;  // must come last due to zero'ing
 } mi_thread_data_t;
 
 
@@ -223,7 +223,7 @@ static mi_thread_data_t* mi_thread_data_zalloc(void) {
   }
   
   if (td != NULL && !is_zero) {
-    _mi_memzero_aligned(td, sizeof(*td));
+    _mi_memzero_aligned(td, offsetof(mi_thread_data_t,memid));
   }
   return td;
 }

Original file line number	Diff line number	Diff line change
`@@ -175,9 +175,9 @@ mi_heap_t* _mi_heap_main_get(void) {`
`175`	`175`
`176`	`176`	// note: in x64 in release build `sizeof(mi_thread_data_t)` is under 4KiB (= OS page size).
`177`	`177`	`typedef struct mi_thread_data_s {`
`178`		- mi_heap_t heap; // must come first due to cast in `_mi_heap_done`
	`178`	+ mi_heap_t heap; // must come first due to cast in `_mi_heap_done`
`179`	`179`	`mi_tld_t tld;`
`180`		`- mi_memid_t memid;`
	`180`	`+ mi_memid_t memid; // must come last due to zero'ing`
`181`	`181`	`} mi_thread_data_t;`
`182`	`182`
`183`	`183`
`@@ -223,7 +223,7 @@ static mi_thread_data_t* mi_thread_data_zalloc(void) {`
`223`	`223`	`}`
`224`	`224`
`225`	`225`	`if (td != NULL && !is_zero) {`
`226`		`- _mi_memzero_aligned(td, sizeof(*td));`
	`226`	`+ _mi_memzero_aligned(td, offsetof(mi_thread_data_t,memid));`
`227`	`227`	`}`
`228`	`228`	`return td;`
`229`	`229`	`}`