malloc: cast size down to int in bin_index functions

[musl] / src / malloc / malloc.c

diff --git a/src/malloc/malloc.c b/src/malloc/malloc.c
index a4eefda..207b6ef 100644 (file)
--- a/src/malloc/malloc.c
+++ b/src/malloc/malloc.c
@@ -1,3 +1,4 @@
+#define _GNU_SOURCE
 #include <stdlib.h>
 #include <string.h>
 #include <limits.h>
@@ -119,14 +120,14 @@ static int bin_index(size_t x)
        x = x / SIZE_ALIGN - 1;
        if (x <= 32) return x;
        if (x > 0x1c00) return 63;
-       return ((union { float v; uint32_t r; }){ x }.r>>21) - 496;
+       return ((union { float v; uint32_t r; }){(int)x}.r>>21) - 496;
 }
 
 static int bin_index_up(size_t x)
 {
        x = x / SIZE_ALIGN - 1;
        if (x <= 32) return x;
-       return ((union { float v; uint32_t r; }){ x }.r+0x1fffff>>21) - 496;
+       return ((union { float v; uint32_t r; }){(int)x}.r+0x1fffff>>21) - 496;
 }
 
 #if 0
@@ -179,7 +180,7 @@ fail:
        return 0;
 }
 
-static int init_malloc()
+static int init_malloc(size_t n)
 {
        static int init, waiters;
        int state;
@@ -196,7 +197,7 @@ static int init_malloc()
 
        mal.brk = __brk(0) + 2*SIZE_ALIGN-1 & -SIZE_ALIGN;
 
-       c = expand_heap(1);
+       c = expand_heap(n);
 
        if (!c) {
                a_store(&init, 0);
@@ -210,7 +211,7 @@ static int init_malloc()
 
        a_store(&init, 2);
        if (waiters) __wake(&init, -1, 1);
-       return 0;
+       return 1;
 }
 
 static int adjust_size(size_t *n)
@@ -333,7 +334,7 @@ void *malloc(size_t n)
        if (adjust_size(&n) < 0) return 0;
 
        if (n > MMAP_THRESHOLD) {
-               size_t len = n + PAGE_SIZE - 1 & -PAGE_SIZE;
+               size_t len = n + OVERHEAD + PAGE_SIZE - 1 & -PAGE_SIZE;
                char *base = __mmap(0, len, PROT_READ|PROT_WRITE,
                        MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
                if (base == (void *)-1) return 0;
@@ -347,7 +348,7 @@ void *malloc(size_t n)
        for (;;) {
                uint64_t mask = mal.binmap & -(1ULL<<i);
                if (!mask) {
-                       init_malloc();
+                       if (init_malloc(n) > 0) continue;
                        c = expand_heap(n);
                        if (!c) return 0;
                        if (alloc_rev(c)) {
@@ -394,7 +395,7 @@ void *realloc(void *p, size_t n)
                size_t oldlen = n0 + extra;
                size_t newlen = n + extra;
                /* Crash on realloc of freed chunk */
-               if ((uintptr_t)base < mal.brk) *(char *)0=0;
+               if ((uintptr_t)base < mal.brk) *(volatile char *)0=0;
                if (newlen < PAGE_SIZE && (new = malloc(n))) {
                        memcpy(new, p, n-OVERHEAD);
                        free(p);
@@ -457,7 +458,7 @@ void free(void *p)
                char *base = (char *)self - extra;
                size_t len = CHUNK_SIZE(self) + extra;
                /* Crash on double free */
-               if ((uintptr_t)base < mal.brk) *(char *)0=0;
+               if ((uintptr_t)base < mal.brk) *(volatile char *)0=0;
                __munmap(base, len);
                return;
        }