journal: filter log based on LogFilterPatterns

Use LogFilterPatterns from the unit's cgroup xattr in order to keep or
discard log messages before writing them to the journal.
When a log message is discarded, it won't be written to syslog, console...
either.

When a native, syslog, or standard output log message is received,
systemd-journald will process it if it matches against at least one
allowed pattern (if any) and none of the denied patterns (if any).

1 files changed, 6 insertions, 0 deletions

diff --git a/src/journal/journald-context.c b/src/journal/journald-context.c
index 222855ae60..55e657c7e1 100644
--- a/src/journal/journald-context.c
+++ b/src/journal/journald-context.c
@@ -14,6 +14,7 @@
 #include "io-util.h"
 #include "journal-internal.h"
 #include "journal-util.h"
+#include "journald-client.h"
 #include "journald-context.h"
 #include "parse-util.h"
 #include "path-util.h"
@@ -180,6 +181,9 @@ static void client_context_reset(Server *s, ClientContext *c) {
 
         c->log_ratelimit_interval = s->ratelimit_interval;
         c->log_ratelimit_burst = s->ratelimit_burst;
+
+        c->log_filter_allowed_patterns = set_free(c->log_filter_allowed_patterns);
+        c->log_filter_denied_patterns = set_free(c->log_filter_denied_patterns);
 }
 
 static ClientContext* client_context_free(Server *s, ClientContext *c) {
@@ -290,6 +294,8 @@ static int client_context_read_cgroup(Server *s, ClientContext *c, const char *u
                 return r;
         }
 
+        (void) client_context_read_log_filter_patterns(c, t);
+
         /* Let's shortcut this if the cgroup path didn't change */
         if (streq_ptr(c->cgroup, t))
                 return 0;