From 3538ba34e0e415105d3fe235605e6dba1597ad98 Mon Sep 17 00:00:00 2001
From: Kjetil Oftedal <oftedal@gmail.com>
Date: Wed, 25 Sep 2019 09:59:46 +0200
Subject: 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 <oftedal@gmail.com>
---
libc/stdlib/malloc/memalign.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/libc/stdlib/malloc/memalign.c b/libc/stdlib/malloc/memalign.c
index 6943279ac..665f20cfb 100644
--- 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;
--
cgit v1.2.3