From: Florian Forster <octo@collectd.org>
Date: Wed, 17 Jun 2015 07:09:17 +0000 (+0200)
Subject: src/utils_llist.c: Handle unlikely corner case.
X-Git-Tag: collectd-5.5.1~110^2~1
X-Git-Url: https://git.octo.it/?a=commitdiff_plain;h=707fa6cb057b53846aaa27a505fe05226612ecd3;p=collectd.git

src/utils_llist.c: Handle unlikely corner case.

This handles the following (unlikely) case:
    (l->head == NULL) && (e == NULL)

In this case, the following code will dereference a NULL pointer:
    if (l->head == e)
      l->head = e->next;
---

diff --git a/src/utils_llist.c b/src/utils_llist.c
index 6a0c6f06..11f838d2 100644
--- a/src/utils_llist.c
+++ b/src/utils_llist.c
@@ -120,6 +120,9 @@ void llist_remove (llist_t *l, llentry_t *e)
 {
 	llentry_t *prev;
 
+	if ((l == NULL) || (e == NULL))
+		return;
+
 	prev = l->head;
 	while ((prev != NULL) && (prev->next != e))
 		prev = prev->next;