Fill the buffer with 'z' instead of 'a' since 'a' is part of the

string we are testing.
Add tests to verify that we get SIGSEGV when passed a NULL src or dst.
It is better to crash than for an implementation to check for NULL
and try to recover.

1 files changed, 76 insertions, 19 deletions

diff --git a/src/regress/lib/libc/strlcat/strlcattest.c b/src/regress/lib/libc/strlcat/strlcattest.c
index cb3624e5a4..155aa6f727 100644
--- a/src/regress/lib/libc/strlcat/strlcattest.c
+++ b/src/regress/lib/libc/strlcat/strlcattest.c
@@ -1,4 +1,4 @@
-/*      $OpenBSD: strlcattest.c,v 1.1 2014/12/02 17:48:34 millert Exp $ */
+/*      $OpenBSD: strlcattest.c,v 1.2 2014/12/03 18:25:18 millert Exp $ */
 
 /*
  * Copyright (c) 2014 Todd C. Miller <Todd.Miller@courtesan.com>
@@ -21,13 +21,27 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <setjmp.h>
+#include <signal.h>
 #include <unistd.h>
 
-int main(int argc, char *argv[])
+volatile sig_atomic_t got_signal;
+sigjmp_buf jmpenv;
+
+void
+handler(int signo)
+{
+        got_signal = signo;
+        siglongjmp(jmpenv, 1);
+}
+
+int
+main(int argc, char *argv[])
 {
         char *buf, *cp, *ep;
-        int failures = 0;
+        struct sigaction sa;
         size_t len, bufsize;
+        int failures = 0;
 
         /* Enable malloc security options. */
         setenv("MALLOC_OPTIONS", "S", 0);
@@ -38,19 +52,21 @@ int main(int argc, char *argv[])
                 fprintf(stderr, "unable to allocate memory\n");
                 return 1;
         }
-        memset(buf, 'a', bufsize);
+        memset(buf, 'z', bufsize);
         ep = buf + bufsize;
 
         /* Test appending to an unterminated string. */
         len = strlcat(buf, "abcd", bufsize);
         if (len != 4 + bufsize) {
-                fprintf(stderr, "strlcat: failed unterminated buffer test (1a)");
+                fprintf(stderr,
+                    "strlcat: failed unterminated buffer test (1a)\n");
                 failures++;
         }
         /* Make sure we only wrote where expected. */
         for (cp = buf; cp < ep; cp++) {
-                if (*cp != 'a') {
-                        fprintf(stderr, "strlcat: failed unterminated buffer test (1b)");
+                if (*cp != 'z') {
+                        fprintf(stderr,
+                            "strlcat: failed unterminated buffer test (1b)\n");
                         failures++;
                         break;
                 }
@@ -60,34 +76,36 @@ int main(int argc, char *argv[])
         ep[-1] = '\0';
         len = strlcat(buf, "abcd", bufsize);
         if (len != 4 + bufsize - 1) {
-                fprintf(stderr, "strlcat: failed full buffer test (2a)");
+                fprintf(stderr, "strlcat: failed full buffer test (2a)\n");
                 failures++;
         }
         /* Make sure we only wrote where expected. */
         for (cp = buf; cp < ep - 1; cp++) {
-                if (*cp != 'a') {
-                        fprintf(stderr, "strlcat: failed full buffer test (2b)");
+                if (*cp != 'z') {
+                        fprintf(stderr,
+                            "strlcat: failed full buffer test (2b)\n");
                         failures++;
                         break;
                 }
         }
 
         /* Test appending to an empty string. */
-        ep[-1] = 'a';
+        ep[-1] = 'z';
         buf[0] = '\0';
         len = strlcat(buf, "abcd", bufsize);
         if (len != 4) {
-                fprintf(stderr, "strlcat: failed empty buffer test (3a)");
+                fprintf(stderr, "strlcat: failed empty buffer test (3a)\n");
                 failures++;
         }
         /* Make sure we only wrote where expected. */
         if (memcmp(buf, "abcd", sizeof("abcd")) != 0) {
-                fprintf(stderr, "strlcat: failed empty buffer test (3b)");
+                fprintf(stderr, "strlcat: failed empty buffer test (3b)\n");
                 failures++;
         }
         for (cp = buf + len + 1; cp < ep; cp++) {
-                if (*cp != 'a') {
-                        fprintf(stderr, "strlcat: failed empty buffer test (3c)");
+                if (*cp != 'z') {
+                        fprintf(stderr,
+                            "strlcat: failed empty buffer test (3c)\n");
                         failures++;
                         break;
                 }
@@ -97,21 +115,60 @@ int main(int argc, char *argv[])
         memcpy(buf, "abcd", sizeof("abcd"));
         len = strlcat(buf, "efgh", bufsize);
         if (len != 8) {
-                fprintf(stderr, "strlcat: failed empty buffer test (4a)");
+                fprintf(stderr, "strlcat: failed empty buffer test (4a)\n");
                 failures++;
         }
         /* Make sure we only wrote where expected. */
         if (memcmp(buf, "abcdefgh", sizeof("abcdefgh")) != 0) {
-                fprintf(stderr, "strlcat: failed empty buffer test (4b)");
+                fprintf(stderr, "strlcat: failed empty buffer test (4b)\n");
                 failures++;
         }
         for (cp = buf + len + 1; cp < ep; cp++) {
-                if (*cp != 'a') {
-                        fprintf(stderr, "strlcat: failed empty buffer test (4c)");
+                if (*cp != 'z') {
+                        fprintf(stderr,
+                            "strlcat: failed empty buffer test (4c)\n");
                         failures++;
                         break;
                 }
         }
 
+        /*
+         * The following tests should result in SIGSEGV, however some
+         * systems may erroneously report SIGBUS.
+         * These tests assume that strlcat() is signal-safe.
+         */
+        memset(&sa, 0, sizeof(sa));
+        sigemptyset(&sa.sa_mask);
+        sa.sa_handler = handler;
+        sigaction(SIGSEGV, &sa, NULL);
+        sigaction(SIGBUS, &sa, NULL);
+
+        /* Test copying to a NULL buffer with non-zero size. */
+        got_signal = 0;
+        if (sigsetjmp(jmpenv, 1) == 0) {
+                len = strlcat(NULL, "abcd", sizeof(buf));
+                fprintf(stderr, "strlcat: failed NULL dst test (5a), "
+                    "expected signal %d, got len %zu\n", SIGSEGV, len);
+                failures++;
+        } else if (got_signal != SIGSEGV) {
+                fprintf(stderr, "strlcat: failed NULL dst test (5b), "
+                    "expected signal %d, got %d\n", SIGSEGV, got_signal);
+                failures++;
+        }
+
+        /* Test copying from a NULL src. */
+        memcpy(buf, "abcd", sizeof("abcd"));
+        got_signal = 0;
+        if (sigsetjmp(jmpenv, 1) == 0) {
+                len = strlcat(buf, NULL, sizeof(buf));
+                fprintf(stderr, "strlcat: failed NULL src test (6a), "
+                    "expected signal %d, got len %zu\n", SIGSEGV, len);
+                failures++;
+        } else if (got_signal != SIGSEGV) {
+                fprintf(stderr, "strlcat: failed NULL src test (6b), "
+                    "expected signal %d, got %d\n", SIGSEGV, got_signal);
+                failures++;
+        }
+
         return failures;
 }