From: Dragan Dosen <ddosen@haproxy.com>
Date: Tue, 7 May 2019 13:25:25 +0000 (+0200)
Subject: BUG/MEDIUM: tasks: fix possible segfault on task_destroy()
X-Git-Tag: v2.0-dev3~83
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=75bc6d3e59a42fae5e5f197186e72ff587fc4ad3;p=thirdparty%2Fhaproxy.git

BUG/MEDIUM: tasks: fix possible segfault on task_destroy()

Commit 3f795f7 ("MEDIUM: tasks: Merge task_delete() and task_free() into
task_destroy().") replaced task_delete() and task_free() with a single
function named task_destroy().

This patch adds a check for struct task* argument in function
task_destroy() to prevent a possible segfault on NULL and also to make
the function safer for use in other cases.
---

diff --git a/include/proto/task.h b/include/proto/task.h
index 859aea385b..f167933231 100644
--- a/include/proto/task.h
+++ b/include/proto/task.h
@@ -331,6 +331,9 @@ static inline void __task_free(struct task *t)
 
 static inline void task_destroy(struct task *t)
 {
+	if (!t)
+		return;
+
 	task_unlink_wq(t);
 	/* We don't have to explicitely remove from the run queue.
 	 * If we are in the runqueue, the test below will set t->process