Commit 3ebe8142 authored by Bjarki Arge Andreasen's avatar Bjarki Arge Andreasen Committed by Fabio Baltieri
Browse files

modem: chat: Patch invalid dereference 



The chat module contains an array of three lists of matches,
one of which are static, two of which are contained within the
currently running script. The current match, which is an
object stored in one of the three lists, is stored in its own
pointer in the chat module context.

A memory error occurs when the script is stopped, while the
chat module is using one of the matches stored withing the
script. This commit clears the match pointer when the script
is stopped if the match is stored within the script.

Signed-off-by: default avatarBjarki Arge Andreasen <bjarki@arge-andreasen.me>
parent ed8578d5

subsys/modem/modem_chat.c

+13 −1
Original line number Diff line number Diff line
@@ -60,7 +60,7 @@ static void modem_chat_log_received_command(struct modem_chat *chat) 


static void modem_chat_script_stop(struct modem_chat *chat, enum modem_chat_script_result result)

{

	if (!chat || !chat->script) {

	if ((chat == NULL) || (chat->script == NULL)) {

		return;

	}
@@ -78,6 +78,14 @@ static void modem_chat_script_stop(struct modem_chat *chat, enum modem_chat_scri 
		chat->script->callback(chat, result, chat->user_data);

	}



	/* Clear parse_match in case it is stored in the script being stopped */

	if ((chat->parse_match != NULL) &&

	    ((chat->parse_match_type == MODEM_CHAT_MATCHES_INDEX_ABORT) ||

	     (chat->parse_match_type == MODEM_CHAT_MATCHES_INDEX_RESPONSE))) {

		chat->parse_match = NULL;

		chat->parse_match_len = 0;

	}



	/* Clear reference to script */

	chat->script = NULL;
@@ -822,4 +830,8 @@ void modem_chat_release(struct modem_chat *chat) 
	chat->parse_match = NULL;

	chat->parse_match_len = 0;

	chat->parse_arg_len = 0;

	chat->matches[MODEM_CHAT_MATCHES_INDEX_ABORT] = NULL;

	chat->matches_size[MODEM_CHAT_MATCHES_INDEX_ABORT] = 0;

	chat->matches[MODEM_CHAT_MATCHES_INDEX_RESPONSE] = NULL;

	chat->matches_size[MODEM_CHAT_MATCHES_INDEX_RESPONSE] = 0;

}

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