systemd: Fix CVE-2022-3821 issue

An off-by-one Error issue was discovered in Systemd in format_timespan()
function of time-util.c. An attacker could supply specific values for
time and accuracy that leads to buffer overrun in format_timespan(),
leading to a Denial of Service.
Add a patch to solve above CVE issue
Link: https://github.com/systemd/systemd/commit/9102c625a673a3246d7e73d8737f3494446bad4e

(From OE-Core rev: e2db40ca49b8ed217f14c7f861087837e8b3f389)

Signed-off-by: Ranjitsinh Rathod <ranjitsinh.rathod@kpit.com>
Signed-off-by: Steve Sakoman <steve@sakoman.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

2 files changed, 48 insertions, 0 deletions

diff --git a/meta/recipes-core/systemd/systemd/CVE-2022-3821.patch b/meta/recipes-core/systemd/systemd/CVE-2022-3821.patch
new file mode 100644
index 0000000000..f9c6704cfc
--- /dev/null
+++ b/meta/recipes-core/systemd/systemd/CVE-2022-3821.patch
@@ -0,0 +1,47 @@
+From 9102c625a673a3246d7e73d8737f3494446bad4e Mon Sep 17 00:00:00 2001
+From: Yu Watanabe <watanabe.yu+github@gmail.com>
+Date: Thu, 7 Jul 2022 18:27:02 +0900
+Subject: [PATCH] time-util: fix buffer-over-run
+
+Fixes #23928.
+
+CVE: CVE-2022-3821
+Upstream-Status: Backport [https://github.com/systemd/systemd/commit/9102c625a673a3246d7e73d8737f3494446bad4e.patch]
+Signed-off-by: Ranjitsinh Rathod <ranjitsinh.rathod@kpit.com>
+Comment: Both the hunks refreshed to backport
+
+---
+ src/basic/time-util.c     | 2 +-
+ src/test/test-time-util.c | 5 +++++
+ 2 files changed, 6 insertions(+), 1 deletion(-)
+
+diff --git a/src/basic/time-util.c b/src/basic/time-util.c
+index abbc4ad5cd70..26d59de12348 100644
+--- a/src/basic/time-util.c
++++ b/src/basic/time-util.c
+@@ -514,7 +514,7 @@ char *format_timespan(char *buf, size_t
+                         t = b;
+                 }
+ 
+-                n = MIN((size_t) k, l);
++                n = MIN((size_t) k, l-1);
+ 
+                 l -= n;
+                 p += n;
+diff --git a/src/test/test-time-util.c b/src/test/test-time-util.c
+index e8e4e2a67bb1..58c5fa9be40c 100644
+--- a/src/test/test-time-util.c
++++ b/src/test/test-time-util.c
+@@ -501,6 +501,12 @@ int main(int argc, char *argv[]) {
+         test_format_timespan(1);
+         test_format_timespan(USEC_PER_MSEC);
+         test_format_timespan(USEC_PER_SEC);
++
++        /* See issue #23928. */
++        _cleanup_free_ char *buf;
++        assert_se(buf = new(char, 5));
++        assert_se(buf == format_timespan(buf, 5, 100005, 1000));
++
+         test_timezone_is_valid();
+         test_get_timezones();
+         test_usec_add();
diff --git a/meta/recipes-core/systemd/systemd_244.5.bb b/meta/recipes-core/systemd/systemd_244.5.bb
index f3e5395465..77ef2bc42f 100644
--- a/meta/recipes-core/systemd/systemd_244.5.bb
+++ b/meta/recipes-core/systemd/systemd_244.5.bb
@@ -33,6 +33,7 @@ SRC_URI += "file://touchscreen.rules \
            file://CVE-2021-3997-1.patch \
            file://CVE-2021-3997-2.patch \
            file://CVE-2021-3997-3.patch \
+           file://CVE-2022-3821.patch \
            "
 
 # patches needed by musl