From: Jérémie Galarneau <jeremie.galarneau@efficios.com>
Date: Tue, 2 Dec 2014 03:07:03 +0000 (-0500)
Subject: Fix: Missing RCU read locks in syscall_list_channel()
X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=24eb8569dc841f318d7964ca9a0ad0a4f9508a8e;p=lttng-tools.git

Fix: Missing RCU read locks in syscall_list_channel()

Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
---

diff --git a/src/bin/lttng-sessiond/syscall.c b/src/bin/lttng-sessiond/syscall.c
index eb81d6742..c38f89109 100644
--- a/src/bin/lttng-sessiond/syscall.c
+++ b/src/bin/lttng-sessiond/syscall.c
@@ -405,11 +405,14 @@ ssize_t syscall_list_channel(struct ltt_kernel_channel *kchan,
 			events = new_events;
 		}
 
+		rcu_read_lock();
 		ksyscall = lookup_syscall(syscalls_ht, syscall_table[i].name);
 		if (ksyscall) {
 			update_event_syscall_bitness(events, i, ksyscall->index);
 			continue;
 		}
+		ksyscall = NULL;
+		rcu_read_unlock();
 
 		ret = add_syscall_to_ht(syscalls_ht, i, count);
 		if (ret < 0) {
@@ -429,7 +432,10 @@ ssize_t syscall_list_channel(struct ltt_kernel_channel *kchan,
 	return count;
 
 error:
+	rcu_read_lock();
 	destroy_syscall_ht(syscalls_ht);
+	rcu_read_unlock();
+
 	free(events);
 	return ret;
 }