X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=src%2Fbasic%2Falloc-util.h;h=ceeee519b79f864ccbf359fede0c91c3364c7e36;hb=d72545b2a0c29e5844c508101cd4720c356193b4;hp=679ba7f398727a7a951711ec3d523bd4fca4922a;hpb=076d998b73bf53e6652ea3ae4bed169e57423741;p=elogind.git

diff --git a/src/basic/alloc-util.h b/src/basic/alloc-util.h
index 679ba7f39..ceeee519b 100644
--- a/src/basic/alloc-util.h
+++ b/src/basic/alloc-util.h
@@ -51,25 +51,29 @@ static inline void freep(void *p) {
 
 #define _cleanup_free_ _cleanup_(freep)
 
-_malloc_  _alloc_(1, 2) static inline void *malloc_multiply(size_t a, size_t b) {
-        if (_unlikely_(b != 0 && a > ((size_t) -1) / b))
+static inline bool size_multiply_overflow(size_t size, size_t need) {
+        return _unlikely_(need != 0 && size > (SIZE_MAX / need));
+}
+
+_malloc_  _alloc_(1, 2) static inline void *malloc_multiply(size_t size, size_t need) {
+        if (size_multiply_overflow(size, need))
                 return NULL;
 
-        return malloc(a * b);
+        return malloc(size * need);
 }
 
-_alloc_(2, 3) static inline void *realloc_multiply(void *p, size_t a, size_t b) {
-        if (_unlikely_(b != 0 && a > ((size_t) -1) / b))
+_alloc_(2, 3) static inline void *realloc_multiply(void *p, size_t size, size_t need) {
+        if (size_multiply_overflow(size, need))
                 return NULL;
 
-        return realloc(p, a * b);
+        return realloc(p, size * need);
 }
 
-_alloc_(2, 3) static inline void *memdup_multiply(const void *p, size_t a, size_t b) {
-        if (_unlikely_(b != 0 && a > ((size_t) -1) / b))
+_alloc_(2, 3) static inline void *memdup_multiply(const void *p, size_t size, size_t need) {
+        if (size_multiply_overflow(size, need))
                 return NULL;
 
-        return memdup(p, a * b);
+        return memdup(p, size * need);
 }
 
 void* greedy_realloc(void **p, size_t *allocated, size_t need, size_t size);