From 628761fe0588c0d5f89921e0f51fa323111cc754 Mon Sep 17 00:00:00 2001 From: Beau Belgrave Date: Thu, 30 Sep 2021 15:38:21 -0700 Subject: [PATCH] tracing: Do not let synth_events block other dyn_event systems during create [ Upstream commit 4f67cca70c0f615e9cfe6ac42244f3416ec60877 ] synth_events is returning -EINVAL if the dyn_event create command does not contain ' \t'. This prevents other systems from getting called back. synth_events needs to return -ECANCELED in these cases when the command is not targeting the synth_event system. Link: https://lore.kernel.org/linux-trace-devel/20210930223821.11025-1-beaub@linux.microsoft.com Fixes: c9e759b1e8456 ("tracing: Rework synthetic event command parsing") Reviewed-by: Masami Hiramatsu Signed-off-by: Beau Belgrave Signed-off-by: Steven Rostedt (VMware) Signed-off-by: Sasha Levin --- kernel/trace/trace_events_synth.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) diff --git a/kernel/trace/trace_events_synth.c b/kernel/trace/trace_events_synth.c index 22db3ce95e74..8c26092db8de 100644 --- a/kernel/trace/trace_events_synth.c +++ b/kernel/trace/trace_events_synth.c @@ -2053,6 +2053,13 @@ static int create_synth_event(const char *raw_command) last_cmd_set(raw_command); + name = raw_command; + + /* Don't try to process if not our system */ + if (name[0] != 's' || name[1] != ':') + return -ECANCELED; + name += 2; + p = strpbrk(raw_command, " \t"); if (!p) { synth_err(SYNTH_ERR_INVALID_CMD, 0); @@ -2061,12 +2068,6 @@ static int create_synth_event(const char *raw_command) fields = skip_spaces(p); - name = raw_command; - - if (name[0] != 's' || name[1] != ':') - return -ECANCELED; - name += 2; - /* This interface accepts group name prefix */ if (strchr(name, '/')) { len = str_has_prefix(name, SYNTH_SYSTEM "/");