From f6333b592b0d574d68e96d04a09a6cae956ee6c3 Mon Sep 17 00:00:00 2001 From: Patrick Griffis Date: Sun, 4 Mar 2018 12:14:09 -0500 Subject: [PATCH] Fix out of bounds read when DCC message sender contains quotes This cannot be triggered by any user generally. Fixes #2128 --- src/common/proto-irc.c | 25 +++++++++++++++++++++++-- 1 file changed, 23 insertions(+), 2 deletions(-) diff --git a/src/common/proto-irc.c b/src/common/proto-irc.c index 969ac2e4..e055c7e2 100644 --- a/src/common/proto-irc.c +++ b/src/common/proto-irc.c @@ -1241,15 +1241,36 @@ process_named_msg (session *sess, char *type, char *word[], char *word_eol[], len = strlen (text); if (text[0] == 1 && text[len - 1] == 1) /* ctcp */ { + char *new_pdibuf = NULL; text[len - 1] = 0; text++; if (g_ascii_strncasecmp (text, "ACTION", 6) != 0) flood_check (nick, ip, serv, sess, 0); if (g_ascii_strncasecmp (text, "DCC ", 4) == 0) - /* redo this with handle_quotes TRUE */ - process_data_init (word[1], word_eol[1], word, word_eol, TRUE, FALSE); + { + int i; + char *new_word[PDIWORDS+1] = { NULL }; + char *new_word_eol[PDIWORDS+1] = { NULL }; + + new_pdibuf = g_malloc (strlen (word_eol[6]) + 1); + + /* This is a bit ugly but we handle the contents of the DCC message containing + * "quoted paths for files" here which means reparsing the message with handle_quotes. + * We avoid reparsing the entire message to avoid corrupting the non DCC parts. + * Greater than PDIWORD length DCC messages will be truncated. */ + process_data_init (new_pdibuf, word_eol[6], new_word, new_word_eol, TRUE, FALSE); + for (i = 6; i < PDIWORDS; ++i) + { + word[i] = new_word[i - 5]; + word_eol[i] = new_word_eol[i - 5]; + } + } + ctcp_handle (sess, to, nick, ip, text, word, word_eol, id, tags_data); + + /* Note word will be invalid beyond this scope */ + g_free (new_pdibuf); } else { if (is_channel (serv, to))