From: Tobias Brunner <tobias@strongswan.org>
Date: Tue, 18 Apr 2023 13:55:10 +0000 (+0200)
Subject: watcher: Make sure to re-activate the correct entry after a callback
X-Git-Tag: 5.9.11rc1~24
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=705a20619f4987983f93be5a26190bbb3c8c5ab9;p=thirdparty%2Fstrongswan.git

watcher: Make sure to re-activate the correct entry after a callback

Since the same FD may be added multiple times (e.g. with separate
callbacks for WATCHER_READ and WATCHER_WRITE), the previous check
might not have found the correct entry.  As the entry can't be removed
while in a callback, the pointer comparison is fine.
---

diff --git a/src/libstrongswan/processing/watcher.c b/src/libstrongswan/processing/watcher.c
index c4d11e9fc6..f78a6c5b1a 100644
--- a/src/libstrongswan/processing/watcher.c
+++ b/src/libstrongswan/processing/watcher.c
@@ -153,6 +153,8 @@ static entry_t *remove_entry(private_watcher_t *this, entry_t *entry,
  * Data we pass on for an async notification
  */
 typedef struct {
+	/** triggering entry */
+	entry_t *entry;
 	/** file descriptor */
 	int fd;
 	/** event type */
@@ -227,7 +229,7 @@ static void notify_end(notify_data_t *data)
 	this->mutex->lock(this->mutex);
 	for (entry = this->fds; entry; prev = entry, entry = entry->next)
 	{
-		if (entry->fd == data->fd)
+		if (entry == data->entry)
 		{
 			if (!data->keep)
 			{
@@ -277,6 +279,7 @@ static void notify(private_watcher_t *this, entry_t *entry,
 
 	/* get a copy of entry for async job, but with specific event */
 	INIT(data,
+		.entry = entry,
 		.fd = entry->fd,
 		.event = event,
 		.cb = entry->cb,