Commit 821bd471 authored Aug 20, 2022 by Steven Rostedt (Google) Committed by Greg Kroah-Hartman Aug 25, 2022

tracing/probes: Have kprobes and uprobes use $COMM too

commit ab8384442ee512fc0fc72deeb036110843d0e7ff upstream.

Both $comm and $COMM can be used to get current->comm in eprobes and the
filtering and histogram logic. Make kprobes and uprobes consistent in this
regard and allow both $comm and $COMM as well. Currently kprobes and
uprobes only handle $comm, which is inconsistent with the other utilities,
and can be confusing to users.

Link: https://lkml.kernel.org/r/20220820134401.317014913@goodmis.org
Link: https://lore.kernel.org/all/20220820220442.776e1ddaf8836e82edb34d01@kernel.org/



Cc: stable@vger.kernel.org
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Tzvetomir Stoyanov <tz.stoyanov@gmail.com>
Cc: Tom Zanussi <zanussi@kernel.org>
Fixes: 533059281ee5 ("tracing: probeevent: Introduce new argument fetching code")
Suggested-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent b37e0f17

kernel/trace/trace_probe.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -361,7 +361,7 @@ static int parse_probe_vars(char arg, const struct fetch_type t,
		}
		} else
		ret = -EINVAL;
		} else if (strcmp(arg, "comm") == 0) {
		} else if (strcmp(arg, "comm") == 0 \|\| strcmp(arg, "COMM") == 0) {
		if (strcmp(t->name, "string") != 0 &&
		strcmp(t->name, "string_size") != 0)
		return -EINVAL;
		@@ -544,7 +544,7 @@ int traceprobe_parse_probe_arg(char arg, ssize_t size,
		* The default type of $comm should be "string", and it can't be
		* dereferenced.
		*/
		if (!t && strcmp(arg, "$comm") == 0)
		if (!t && (strcmp(arg, "$comm") == 0 \|\| strcmp(arg, "$COMM") == 0))
		t = "string";
		parg->type = find_fetch_type(t, ftbl);
		if (!parg->type) {