util: check for overflow in greedy_realloc()

[elogind.git] / src / shared / util.c

diff --git a/src/shared/util.c b/src/shared/util.c
index c71293106f228910d52323957b78e1baa9cbaf4b..1c35edfbb19595027742df31e6fa4c0f4280267a 100644 (file)
--- a/src/shared/util.c
+++ b/src/shared/util.c
@@ -59,6 +59,7 @@
 #include <langinfo.h>
 #include <locale.h>
 #include <libgen.h>
+#undef basename
 
 #include "macro.h"
 #include "util.h"
@@ -3961,8 +3962,8 @@ int fopen_temporary(const char *path, FILE **_f, char **_temp_path) {
         if (!t)
                 return -ENOMEM;
 
-        fn = path_get_file_name(path);
-        k = fn-path;
+        fn = basename(path);
+        k = fn - path;
         memcpy(t, path, k);
         t[k] = '.';
         stpcpy(stpcpy(t+k+1, fn), "XXXXXX");
@@ -4147,7 +4148,7 @@ int symlink_atomic(const char *from, const char *to) {
         if (!t)
                 return -ENOMEM;
 
-        fn = path_get_file_name(to);
+        fn = basename(to);
         k = fn-to;
         memcpy(t, to, k);
         t[k] = '.';
@@ -5791,12 +5792,18 @@ void* greedy_realloc(void **p, size_t *allocated, size_t need) {
         size_t a;
         void *q;
 
+        assert(p);
         assert(allocated);
 
         if (*allocated >= need)
                 return *p;
 
         a = MAX(64u, need * 2);
+
+        /* check for overflows */
+        if (a < need)
+                return NULL;
+
         q = realloc(*p, a);
         if (!q)
                 return NULL;
@@ -5807,9 +5814,14 @@ void* greedy_realloc(void **p, size_t *allocated, size_t need) {
 }
 
 void* greedy_realloc0(void **p, size_t *allocated, size_t need) {
-        size_t prev = *allocated;
+        size_t prev;
         uint8_t *q;
 
+        assert(p);
+        assert(allocated);
+
+        prev = *allocated;
+
         q = greedy_realloc(p, allocated, need);
         if (!q)
                 return NULL;