Don't cleanup the dns_message_checksig fuzzer in atexit handler

After the dns_badcache refactoring, the dns_badcache_destroy() would
call call_rcu().  The dns_message_checksig cleanup which calls
dns_view_detach() happens in the atexit handler, so there might be
call_rcu threads started very late in the process.  The liburcu
registers library destructor that destroys the data structured internal
to liburcu and this clashes with the call_rcu thread that just got
started in the atexit() handler causing either (depending on timing):

 - a normal run
 - a straight segfault
 - an assertion failure from liburcu

Instead of trying to cleanup the dns_message_checksig unit, ignore the
leaked memory as we do with all the other fuzzing tests.

diff --git a/fuzz/dns_message_checksig.c b/fuzz/dns_message_checksig.c
index a6544b80dc2800f8c80d62329dbb5986741c2b5d..f3385ab4a818c3e27fa3b94e221214429f3694cf 100644 (file)
--- a/fuzz/dns_message_checksig.c
+++ b/fuzz/dns_message_checksig.c
@@ -126,57 +126,6 @@ sig0key. 0 IN KEY 512 3 8 AwEAAa22lgHi1vAbQvu5ETdTrm2H8rwga9tvyMa6LFiSDyevLvSv0U
 
 static bool destroy_dst = false;
 
-static void
-cleanup(void) {
-       char pathbuf[PATH_MAX];
-       char *pwd = getcwd(pathbuf, sizeof(pathbuf));
-
-       if (view != NULL) {
-               dns_view_detach(&view);
-       }
-       if (tsigkey != NULL) {
-               dns_tsigkey_detach(&tsigkey);
-       }
-       if (ring != NULL) {
-               dns_tsigkeyring_detach(&ring);
-       }
-       if (emptyring != NULL) {
-               dns_tsigkeyring_detach(&emptyring);
-       }
-       if (destroy_dst) {
-               dst_lib_destroy();
-       }
-       if (mctx != NULL) {
-               isc_mem_detach(&mctx);
-       }
-       if (wd != NULL && chdir(wd) == 0) {
-               if (remove(f1) != 0) {
-                       fprintf(stderr, "remove(%s) failed\n", f1);
-               }
-               if (remove(f2) != 0) {
-                       fprintf(stderr, "remove(%s) failed\n", f2);
-               }
-               if (remove(f3) != 0) {
-                       fprintf(stderr, "remove(%s) failed\n", f3);
-               }
-               /*
-                * Restore working directory if possible before cleaning
-                * up the key directory.  This will help with any other
-                * cleanup routines as the directory should not be in use
-                * when rmdir() is called.
-                */
-               if (pwd != NULL && chdir(pwd) != 0) {
-                       fprintf(stderr, "can't restore working directory: %s\n",
-                               pwd);
-               }
-               if (rmdir(wd) != 0) {
-                       fprintf(stderr, "rmdir(%s) failed\n", wd);
-               }
-       } else {
-               fprintf(stderr, "cleanup of %s failed\n", wd ? wd : "(null)");
-       }
-}
-
 int
 LLVMFuzzerInitialize(int *argc ISC_ATTR_UNUSED, char ***argv ISC_ATTR_UNUSED) {
        isc_result_t result;
@@ -189,8 +138,6 @@ LLVMFuzzerInitialize(int *argc ISC_ATTR_UNUSED, char ***argv ISC_ATTR_UNUSED) {
        char pathbuf[PATH_MAX];
        FILE *fd;
 
-       atexit(cleanup);
-
        wd = mkdtemp(template);
        if (wd == NULL) {
                fprintf(stderr, "mkdtemp failed\n");