From: Siavash Tavakoli <siavash.tavakoli@open-xchange.com>
Date: Fri, 4 Jun 2021 22:00:21 +0000 (+0100)
Subject: dict-file: Make sure home_dir doesn't change during operations
X-Git-Tag: 2.3.17~350
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=60cbb2959c614ac9777bb9511bc6f4e0f81aeb90;p=thirdparty%2Fdovecot%2Fcore.git

dict-file: Make sure home_dir doesn't change during operations

file_dict is initialized for a specific user. Keep record of the user's
home_dir and check for all dict operations that the user did not change.
---

diff --git a/src/lib-dict/dict-file.c b/src/lib-dict/dict-file.c
index b101871be7..8a3942fec3 100644
--- a/src/lib-dict/dict-file.c
+++ b/src/lib-dict/dict-file.c
@@ -27,6 +27,8 @@ struct file_dict {
 	enum file_lock_method lock_method;
 
 	char *path;
+	char *home_dir;
+	bool dict_path_checked;
 	HASH_TABLE(char *, char *) hash;
 	int fd;
 
@@ -52,6 +54,28 @@ static struct dotlock_settings file_dict_dotlock_settings = {
 	.use_io_notify = TRUE
 };
 
+static int
+file_dict_ensure_path_home_dir(struct file_dict *dict, const char *home_dir,
+			       const char **error_r)
+{
+	if (null_strcmp(dict->home_dir, home_dir) == 0)
+		return 0;
+
+	if (dict->dict_path_checked) {
+		*error_r = t_strdup_printf("home_dir changed from %s to %s "
+				"(requested dict was: %s)", dict->home_dir,
+				home_dir, dict->path);
+		return -1;
+	}
+
+	char *_p = dict->path;
+	dict->path = i_strdup(home_expand_tilde(dict->path, home_dir));
+	dict->home_dir = i_strdup(home_dir);
+	i_free(_p);
+	dict->dict_path_checked = TRUE;
+	return 0;
+}
+
 static int
 file_dict_init(struct dict *driver, const char *uri,
 	       const struct dict_settings *set ATTR_UNUSED,
@@ -79,6 +103,11 @@ file_dict_init(struct dict *driver, const char *uri,
 			return -1;
 		}
 	}
+
+	/* keep the path for now, later in dict operations check if home_dir
+	   should be prepended. */
+	dict->path = i_strdup(path);
+
 	dict->dict = *driver;
 	dict->hash_pool = pool_alloconly_create("file dict", 1024);
 	hash_table_create(&dict->hash, dict->hash_pool, 0, str_hash, strcmp);
@@ -95,6 +124,7 @@ static void file_dict_deinit(struct dict *_dict)
 	hash_table_destroy(&dict->hash);
 	pool_unref(&dict->hash_pool);
 	i_free(dict->path);
+	i_free(dict->home_dir);
 	i_free(dict);
 }
 
@@ -192,12 +222,15 @@ static int file_dict_refresh(struct file_dict *dict, const char **error_r)
 }
 
 static int file_dict_lookup(struct dict *_dict,
-			    const struct dict_op_settings *set ATTR_UNUSED,
+			    const struct dict_op_settings *set,
 			    pool_t pool, const char *key,
 			    const char **value_r, const char **error_r)
 {
 	struct file_dict *dict = (struct file_dict *)_dict;
 
+	if (file_dict_ensure_path_home_dir(dict, set->home_dir, error_r) < 0)
+		return -1;
+
 	if (file_dict_refresh(dict, error_r) < 0)
 		return -1;
 
@@ -224,7 +257,8 @@ file_dict_iterate_init(struct dict *_dict,
 	ctx->path_len = strlen(path);
 	ctx->flags = flags;
 
-	if (file_dict_refresh(dict, &error) < 0)
+	if (file_dict_ensure_path_home_dir(dict, set->home_dir, &error) < 0 ||
+	    file_dict_refresh(dict, &error) < 0)
 		ctx->error = p_strdup(pool, error);
 
 	ctx->iter = hash_table_iterate_init(dict->hash);
@@ -520,6 +554,9 @@ file_dict_write_changes(struct dict_transaction_memory_context *ctx,
 
 	*atomic_inc_not_found_r = FALSE;
 
+	if (file_dict_ensure_path_home_dir(dict, ctx->ctx.set.home_dir, error_r) < 0)
+		return -1;
+
 	switch (dict->lock_method) {
 	case FILE_LOCK_METHOD_FCNTL:
 	case FILE_LOCK_METHOD_FLOCK: