From e7e70f575840cd021f6429f264911ae0cbff9741 Mon Sep 17 00:00:00 2001
From: Evgeny Vereshchagin <evvers@ya.ru>
Date: Thu, 15 Nov 2018 17:52:57 +0100
Subject: [PATCH] tests: add a fuzzer for dev_kmsg_record

(cherry picked from commit 8857fb9beb9dcb95a6ce1be14dc94c4dc4cd3ea3)

Resolves: #1764560
---
 src/fuzz/fuzz-journald-kmsg.c                 | 29 +++++++++++++++++++
 src/fuzz/meson.build                          |  5 ++++
 src/journal/journald-kmsg.c                   |  2 +-
 src/journal/journald-kmsg.h                   |  2 ++
 test/fuzz/fuzz-journald-kmsg/basic            |  1 +
 test/fuzz/fuzz-journald-kmsg/dev-null         |  2 ++
 test/fuzz/fuzz-journald-kmsg/loopback         |  2 ++
 .../fuzz-journald-kmsg/subsystem-loopback     |  2 ++
 8 files changed, 44 insertions(+), 1 deletion(-)
 create mode 100644 src/fuzz/fuzz-journald-kmsg.c
 create mode 100644 test/fuzz/fuzz-journald-kmsg/basic
 create mode 100644 test/fuzz/fuzz-journald-kmsg/dev-null
 create mode 100644 test/fuzz/fuzz-journald-kmsg/loopback
 create mode 100644 test/fuzz/fuzz-journald-kmsg/subsystem-loopback

diff --git a/src/fuzz/fuzz-journald-kmsg.c b/src/fuzz/fuzz-journald-kmsg.c
new file mode 100644
index 0000000000..5d99d244b5
--- /dev/null
+++ b/src/fuzz/fuzz-journald-kmsg.c
@@ -0,0 +1,29 @@
+/* SPDX-License-Identifier: LGPL-2.1+ */
+
+#include "fuzz.h"
+#include "journald-kmsg.h"
+
+int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
+        Server s = {};
+        _cleanup_free_ char *buffer = NULL;
+
+        if (size == 0)
+                return 0;
+
+        s = (Server) {
+                .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(data, size);
+        assert_se(buffer);
+        dev_kmsg_record(&s, buffer, size);
+        server_done(&s);
+
+        return 0;
+}
diff --git a/src/fuzz/meson.build b/src/fuzz/meson.build
index 1f8631bcc0..0520e448a9 100644
--- a/src/fuzz/meson.build
+++ b/src/fuzz/meson.build
@@ -33,6 +33,11 @@ fuzzers += [
           libshared],
          [libmount]],
 
+        [['src/fuzz/fuzz-journald-kmsg.c'],
+         [libjournal_core,
+          libshared],
+         [libselinux]],
+
         [['src/fuzz/fuzz-journald-native.c',
           'src/fuzz/fuzz-journald.c'],
          [libjournal_core,
diff --git a/src/journal/journald-kmsg.c b/src/journal/journald-kmsg.c
index 7644bebfc8..0cdf1c4794 100644
--- a/src/journal/journald-kmsg.c
+++ b/src/journal/journald-kmsg.c
@@ -93,7 +93,7 @@ static bool is_us(const char *identifier, const char *pid) {
                streq(identifier, program_invocation_short_name);
 }
 
-static void dev_kmsg_record(Server *s, char *p, size_t l) {
+void dev_kmsg_record(Server *s, char *p, size_t l) {
 
         _cleanup_free_ char *message = NULL, *syslog_priority = NULL, *syslog_pid = NULL, *syslog_facility = NULL, *syslog_identifier = NULL, *source_time = NULL, *identifier = NULL, *pid = NULL;
         struct iovec iovec[N_IOVEC_META_FIELDS + 7 + N_IOVEC_KERNEL_FIELDS + 2 + N_IOVEC_UDEV_FIELDS];
diff --git a/src/journal/journald-kmsg.h b/src/journal/journald-kmsg.h
index bff24ac310..2326bc8c93 100644
--- a/src/journal/journald-kmsg.h
+++ b/src/journal/journald-kmsg.h
@@ -9,3 +9,5 @@ int server_flush_dev_kmsg(Server *s);
 void server_forward_kmsg(Server *s, int priority, const char *identifier, const char *message, const struct ucred *ucred);
 
 int server_open_kernel_seqnum(Server *s);
+
+void dev_kmsg_record(Server *s, char *p, size_t l);
diff --git a/test/fuzz/fuzz-journald-kmsg/basic b/test/fuzz/fuzz-journald-kmsg/basic
new file mode 100644
index 0000000000..1299cd0869
--- /dev/null
+++ b/test/fuzz/fuzz-journald-kmsg/basic
@@ -0,0 +1 @@
+29,456,292891883,-;systemd[1]: Reexecuting.
diff --git a/test/fuzz/fuzz-journald-kmsg/dev-null b/test/fuzz/fuzz-journald-kmsg/dev-null
new file mode 100644
index 0000000000..de039588b5
--- /dev/null
+++ b/test/fuzz/fuzz-journald-kmsg/dev-null
@@ -0,0 +1,2 @@
+12,460,1322026586,-;hey
+ DEVICE=c1:3
diff --git a/test/fuzz/fuzz-journald-kmsg/loopback b/test/fuzz/fuzz-journald-kmsg/loopback
new file mode 100644
index 0000000000..ca320177b7
--- /dev/null
+++ b/test/fuzz/fuzz-journald-kmsg/loopback
@@ -0,0 +1,2 @@
+12,460,1322026586,-;hey
+ DEVICE=n1
diff --git a/test/fuzz/fuzz-journald-kmsg/subsystem-loopback b/test/fuzz/fuzz-journald-kmsg/subsystem-loopback
new file mode 100644
index 0000000000..af9c0d91e5
--- /dev/null
+++ b/test/fuzz/fuzz-journald-kmsg/subsystem-loopback
@@ -0,0 +1,2 @@
+12,460,1322026586,-;hey
+ DEVICE=+net:lo