test framework: Correctly generate new paths in noopchroot

The allocated buffer was one byte too small. Allocate a buffer
of PATH_MAX instead and use snprintf(), as suggested by Martin
Pitt.

diff --git a/test/integration/framework b/test/integration/framework
index 691eb793b8535a4b5a9b8bac0b45ab7dfe8f2330..8ea1e1c0d1259e3044d8765f0e543a463c2edfbe 100644 (file)
--- a/test/integration/framework
+++ b/test/integration/framework
@@ -477,6 +477,7 @@ configdpkgnoopchroot() {
 #include <stdlib.h>
 #include <string.h>
 #include <dlfcn.h>
+#include <limits.h>
 
 static char * chrootdir = NULL;
 
@@ -493,13 +494,11 @@ int execvp(const char *file, char *const argv[]) {
        if (chrootdir == NULL || strncmp(file, "/var/lib/dpkg/", strlen("/var/lib/dpkg/")) != 0)
                return func_execvp(file, argv);
        printf("REWRITE execvp call %s into %s\n", file, chrootdir);
-       char newfile[strlen(chrootdir) + strlen(file)];
-       strcpy(newfile, chrootdir);
-       strcat(newfile, file);
+       char newfile[PATH_MAX];
+       snprintf(newfile, sizeof(newfile), "%s/%s", chrootdir, file);
        char const * const baseadmindir = "/var/lib/dpkg";
-       char admindir[strlen(chrootdir) + strlen(baseadmindir)];
-       strcpy(admindir, chrootdir);
-       strcat(admindir, baseadmindir);
+       char admindir[PATH_MAX];
+       snprintf(admindir, sizeof(admindir), "%s/%s", chrootdir, baseadmindir);
        setenv("DPKG_ADMINDIR", admindir, 1);
        return func_execvp(newfile, argv);
 }