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From 4b0ebd414553f9ccab85dfd708bf808127da505f Mon Sep 17 00:00:00 2001
From: Michal Sekletar <msekleta@redhat.com>
Date: Wed, 16 Jan 2019 10:24:56 +0100
Subject: [PATCH] journald: free cmdline buffers owned by iovec

Resolves: #1666646

[msekleta: this is a followup for the fix of CVE-2018-16864. While
backporting upstream changes I've accidentally dropped the automatic
cleanup of the cmdline buffers. Technically speaking similar issue is in
coredump.c too, but after we dispatch iovec buffer in coredump.c we
immediately exit so allocated memory is reclaimed by the kernel.]
---
 src/journal/journald-server.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/journal/journald-server.c b/src/journal/journald-server.c
index c35858247b..88d8f3e41d 100644
--- a/src/journal/journald-server.c
+++ b/src/journal/journald-server.c
@@ -738,6 +738,7 @@ static void dispatch_message_real(
                 o_uid[sizeof("OBJECT_UID=") + DECIMAL_STR_MAX(uid_t)],
                 o_gid[sizeof("OBJECT_GID=") + DECIMAL_STR_MAX(gid_t)],
                 o_owner_uid[sizeof("OBJECT_SYSTEMD_OWNER_UID=") + DECIMAL_STR_MAX(uid_t)];
+        _cleanup_free_ char *cmdline1 = NULL, *cmdline2 = NULL;
         uid_t object_uid;
         gid_t object_gid;
         char *x;
@@ -790,7 +791,7 @@ static void dispatch_message_real(
                 if (r >= 0) {
                         /* At most _SC_ARG_MAX (2MB usually), which is too much to put on stack.
                          * Let's use a heap allocation for this one. */
-                        set_iovec_field_free(iovec, &n, "_CMDLINE=", t);
+                        cmdline1 = set_iovec_field_free(iovec, &n, "_CMDLINE=", t);
                 }
 
                 r = get_process_capeff(ucred->pid, &t);
@@ -916,7 +917,7 @@ static void dispatch_message_real(
 
                 r = get_process_cmdline(object_pid, 0, false, &t);
                 if (r >= 0)
-                        set_iovec_field_free(iovec, &n, "OBJECT_CMDLINE=", t);
+                        cmdline2 = set_iovec_field_free(iovec, &n, "OBJECT_CMDLINE=", t);
 
 #ifdef HAVE_AUDIT
                 r = audit_session_from_pid(object_pid, &audit);