From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Date: Wed, 3 Feb 2021 15:21:42 +0000 (-0500)
Subject: Fix: use MT-safe strtok_r in multithreaded context
X-Git-Tag: v2.13.0-rc1~360
X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=50e0fa5f7abf4f70ffaafc65309f3509897d84c4;p=lttng-tools.git

Fix: use MT-safe strtok_r in multithreaded context

append_list_to_probes uses the non-multithread-safe "strtok" while in
multithreaded context.

It is called by modprobe_lttng_data(), which is called from
init_kernel_tracer().

init_kernel_tracer is used from main() after other threads are created,
and also from process_client_msg() when a user attempts to interact with
the kernel domain if the kernel tracer has not yet been successfully
initialized.

Fixed by using the MT-safe strtok_r() instead.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
Change-Id: Ic3f81551b8508451e0f9733c5de56a4d4407b813
---

diff --git a/src/bin/lttng-sessiond/modprobe.c b/src/bin/lttng-sessiond/modprobe.c
index 2f6d585d5..28385ea39 100644
--- a/src/bin/lttng-sessiond/modprobe.c
+++ b/src/bin/lttng-sessiond/modprobe.c
@@ -625,7 +625,7 @@ static int append_list_to_probes(const char *list)
 {
 	char *next;
 	int ret;
-	char *tmp_list, *cur_list;
+	char *tmp_list, *cur_list, *saveptr;
 
 	assert(list);
 
@@ -639,7 +639,7 @@ static int append_list_to_probes(const char *list)
 		size_t name_len;
 		struct kern_modules_param *cur_mod;
 
-		next = strtok(cur_list, ",");
+		next = strtok_r(cur_list, ",", &saveptr);
 		if (!next) {
 			break;
 		}