talons

commit 3acca60b6efd93f23607754305a9810b56b44efd
parent 40bb4034e4d657f279713f61cd5ca873a90a0489
Author: wwp <subscript@free.fr>
Date:   Sun,  6 Sep 2020 11:41:34 +0200

Fix bug 4313 "Recursion stack overflow with rebuilding folder tree" by
limiting the IMAP rebuild-folder-tree recursion depth to 64 (hidden pref).

Diffstat:
M
src/imap.c
 | 
33
+++++++++++++++++++++++++++++++--
M
src/prefs_common.c
 | 
2
++
M
src/prefs_common.h
 | 
1
+

3 files changed, 34 insertions(+), 2 deletions(-)
diff --git a/src/imap.c b/src/imap.c
@@ -123,6 +123,8 @@ struct _IMAPSession
 	gboolean cancelled;
 	gboolean sens_update_block;
 	gboolean do_destroy;
+
+    gint scan_tree_recurs_depth;
 };
 
 struct _IMAPNameSpace
@@ -278,6 +280,9 @@ static gint imap_auth			(IMAPSession	*session,
 static gint imap_scan_tree_recursive	(IMAPSession	*session,
 					 FolderItem	*item,
 					 gboolean	 subs_only);
+static gint imap_scan_tree_recursive_dive	(IMAPSession	*session,
+					 FolderItem	*item,
+					 gboolean	 subs_only);
 
 static void imap_create_missing_folders	(Folder		*folder);
 static FolderItem *imap_create_special_folder
@@ -2752,6 +2757,14 @@ static gint imap_scan_tree(Folder *folder)
 
 static gint imap_scan_tree_recursive(IMAPSession *session, FolderItem *item, gboolean subs_only)
 {
+    /* reset recursion depth counter */
+    session->scan_tree_recurs_depth = 0;
+
+    return imap_scan_tree_recursive_dive(session, item, subs_only);
+}
+
+static gint imap_scan_tree_recursive_dive(IMAPSession *session, FolderItem *item, gboolean subs_only)
+{
 	Folder *folder;
 	IMAPFolder *imapfolder;
 	FolderItem *new_item;
@@ -2768,6 +2781,15 @@ static gint imap_scan_tree_recursive(IMAPSession *session, FolderItem *item, gbo
 	g_return_val_if_fail(item->folder != NULL, -1);
 	g_return_val_if_fail(item->no_sub == FALSE, -1);
 
+    /* recursion depth limiter */
+    if(session->scan_tree_recurs_depth >= prefs_common.imap_scan_tree_recurs_limit) {
+        g_warning("IMAP scan tree recursion limit reached (%d, folder '%s')",
+                prefs_common.imap_scan_tree_recurs_limit, item->folder->name);
+        return -1;
+    }
+    /* entering recursion func: increase depth counter */
+    session->scan_tree_recurs_depth++;
+
 	folder = item->folder;
 	imapfolder = IMAP_FOLDER(folder);
 
@@ -2895,8 +2917,15 @@ static gint imap_scan_tree_recursive(IMAPSession *session, FolderItem *item, gbo
 			g_free(base);
 		}
 
-		if (new_item->no_sub == FALSE)
-			imap_scan_tree_recursive(session, new_item, subs_only);
+		if (new_item->no_sub == FALSE) {
+			imap_scan_tree_recursive_dive(session, new_item, subs_only);
+
+            /* entering recursion func: increase depth counter */
+            session->scan_tree_recurs_depth--;
+            if (session->scan_tree_recurs_depth < 0)
+                g_error("IMAP scan tree recursion underflow (%d)",
+                        session->scan_tree_recurs_depth);
+        }
 	}
 
 	g_slist_free(item_list);
diff --git a/src/prefs_common.c b/src/prefs_common.c
@@ -1163,6 +1163,8 @@ static PrefParam param[] = {
 	 NULL, NULL, NULL},
 
 	/* Hidden */
+	{"imap_scan_tree_recurs_limit", "64", &prefs_common.imap_scan_tree_recurs_limit, P_INT,
+	 NULL, NULL, NULL},
 	{"warn_dnd", "1", &prefs_common.warn_dnd, P_INT,
 	 NULL, NULL, NULL},
 	{"utf8_instead_of_locale_for_broken_mail", "0", 
diff --git a/src/prefs_common.h b/src/prefs_common.h
@@ -537,6 +537,7 @@ struct _PrefsCommon
 	gint news_subscribe_width;
 	gint news_subscribe_height;
 
+    gint imap_scan_tree_recurs_limit;
 	gint warn_dnd;
 	gint broken_are_utf8;
 	gint skip_ssl_cert_check;