From: Andre Noll <maan@tuebingen.mpg.de>
Date: Thu, 17 Mar 2022 19:36:06 +0000 (+0100)
Subject: afs.c: Improve documentation of activate_mood_or_playlist().
X-Git-Tag: v0.7.1~26
X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=commitdiff_plain;h=425bd709b2df8dc2754678ca28c91b1534d26078

afs.c: Improve documentation of activate_mood_or_playlist().

It is not obvious when arg and current_mop can alias each other so
add an explanatory comment.
---

diff --git a/afs.c b/afs.c
index 031a0099..522615a3 100644
--- a/afs.c
+++ b/afs.c
@@ -481,6 +481,12 @@ static int activate_mood_or_playlist(const char *arg, int *num_admissible,
 	if (num_admissible)
 		*num_admissible = ret;
 	current_play_mode = mode;
+	/*
+	 * We get called with arg == current_mop from the signal dispatcher
+	 * after SIGHUP and from the error path of the select command to
+	 * re-select the current mood or playlist. In this case the assignment
+	 * to current_mop below would result in a use-after-free condition.
+	 */
 	if (arg != current_mop) {
 		free(current_mop);
 		if (arg) {