tests: add a fuzzer for process_audit_string

src/fuzz/fuzz-journald-audit.c

@@ -0,0 +1,27 @@
+/* SPDX-License-Identifier: LGPL-2.1+ */
+
+#include "fuzz.h"
+#include "journald-audit.h"
+
+int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
+        Server s;
+        _cleanup_free_ char *buffer = NULL;
+
+        s = (Server) {
+                .syslog_fd = -1,
+                .native_fd = -1,
+                .stdout_fd = -1,
+                .dev_kmsg_fd = -1,
+                .audit_fd = -1,
+                .hostname_fd = -1,
+                .notify_fd = -1,
+                .storage = STORAGE_NONE,
+        };
+        assert_se(sd_event_default(&s.event) >= 0);
+        buffer = memdup_suffix0(data, size);
+        assert_se(buffer);
+        process_audit_string(&s, 0, buffer, size);
+        server_done(&s);
+
+        return 0;
+}

src/fuzz/meson.build

@@ -51,6 +51,11 @@ fuzzers += [
           libshared],
          [libmount]],
 
+        [['src/fuzz/fuzz-journald-audit.c'],
+         [libjournal_core,
+          libshared],
+         [libselinux]],
+
         [['src/fuzz/fuzz-journald-kmsg.c'],
          [libjournal_core,
           libshared],

src/journal/journald-audit.c

@@ -313,7 +313,7 @@ static int map_all_fields(
         }
 }
 
-static void process_audit_string(Server *s, int type, const char *data, size_t size) {
+void process_audit_string(Server *s, int type, const char *data, size_t size) {
         size_t n_iov_allocated = 0, n_iov = 0, z;
         _cleanup_free_ struct iovec *iov = NULL;
         uint64_t seconds, msec, id;

src/journal/journald-audit.h

@@ -6,4 +6,6 @@
 
 void server_process_audit_message(Server *s, const void *buffer, size_t buffer_size, const struct ucred *ucred, const union sockaddr_union *sa, socklen_t salen);
 
+void process_audit_string(Server *s, int type, const char *data, size_t size);
+
 int server_open_audit(Server*s);

test/fuzz/fuzz-journald-audit/basic

@@ -0,0 +1 @@
+audit(1542398162.211:744): pid=7376 uid=1000 auid=1000 ses=6 subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 msg='op=PAM:accounting grantors=pam_unix,pam_localuser acct="vagrant" exe="/usr/bin/sudo" hostname=? addr=? terminal=/dev/pts/1 res=success'