提交: 3538ba34e0e415105d3fe235605e6dba1597ad98 - uclibc-ng (git)

Commit MetaInfo

• 修訂: 3538ba34e0e415105d3fe235605e6dba1597ad98 (tree)
• 時間: 2019-10-01 02:29:07
• 作者: Kjetil Oftedal <oftedal@gmai...>
• Commiter: Waldemar Brodkorb

Log Message

malloc: Add missing locks for some paths (valloc/memalign/posix_memalign)

The internal heap structures were not protected properly in
memalign(). If multiple threads were concurrently allocating memory and
one of them were requesting aligned memory via valloc,memalign or
posix_memalign the internal heap data structures could be corrupted.

Signed-off-by: Kjetil Oftedal <[e-mail]>

Change Summary

• modified: libc/stdlib/malloc/memalign.c

差異

--- a/libc/stdlib/malloc/memalign.c
+++ b/libc/stdlib/malloc/memalign.c
@@ -77,7 +77,9 @@ memalign (size_t alignment, size_t size)
 	  init_size = addr - tot_addr;
 	}
 
+      __heap_lock (&__malloc_heap_lock);
       __heap_free (heap, base, init_size);
+      __heap_unlock (&__malloc_heap_lock);
 
       /* Remember that we've freed the initial part of MEM.  */
       base += init_size;
@@ -85,9 +87,11 @@ memalign (size_t alignment, size_t size)
 
   /* Return the end part of MEM to the heap, unless it's too small.  */
   end_addr = addr + size;
-  if (end_addr + MALLOC_REALLOC_MIN_FREE_SIZE < tot_end_addr)
+  if (end_addr + MALLOC_REALLOC_MIN_FREE_SIZE < tot_end_addr) {
+    __heap_lock (&__malloc_heap_lock);
     __heap_free (heap, (void *)end_addr, tot_end_addr - end_addr);
-  else
+    __heap_unlock (&__malloc_heap_lock);
+  } else
     /* We didn't free the end, so include it in the size.  */
     end_addr = tot_end_addr;