imap: Fixed crash in IDLE if DONE is received while sending large output to client.

Fixes assert-crash with backtrace:

diff --git a/src/imap/cmd-idle.c b/src/imap/cmd-idle.c
index be4028f4a5d5f399917fc150d6592e684e218bb3..944bb12427e4a966279d7c8a80d3fee3242d8ce9 100644 (file)
--- a/src/imap/cmd-idle.c
+++ b/src/imap/cmd-idle.c
@@ -136,13 +136,13 @@ static void keepalive_timeout(struct cmd_idle_context *ctx)
        idle_add_keepalive_timeout(ctx);
 }
 
-static void idle_sync_now(struct mailbox *box, struct cmd_idle_context *ctx)
+static bool idle_sync_now(struct mailbox *box, struct cmd_idle_context *ctx)
 {
        i_assert(ctx->sync_ctx == NULL);
 
        ctx->sync_pending = FALSE;
        ctx->sync_ctx = imap_sync_init(ctx->client, box, 0, 0);
-       (void)cmd_idle_continue(ctx->cmd);
+       return cmd_idle_continue(ctx->cmd);
 }
 
 static void idle_callback(struct mailbox *box, struct cmd_idle_context *ctx)
@@ -153,7 +153,7 @@ static void idle_callback(struct mailbox *box, struct cmd_idle_context *ctx)
                ctx->sync_pending = TRUE;
        else {
                ctx->manual_cork = TRUE;
-               idle_sync_now(box, ctx);
+               (void)idle_sync_now(box, ctx);
                if (client->disconnected)
                        client_destroy(client, NULL);
        }
@@ -247,11 +247,11 @@ static bool cmd_idle_continue(struct client_command_context *cmd)
 
        if (ctx->sync_pending) {
                /* more changes occurred while we were sending changes to
-                  client */
-               idle_sync_now(client->mailbox, ctx);
-               /* NOTE: this recurses back to this function,
+                  client.
+
+                  NOTE: this recurses back to this function,
                   so we return here instead of doing everything twice. */
-               return FALSE;
+               return idle_sync_now(client->mailbox, ctx);
        }
        if (ctx->to_hibernate == NULL)
                idle_add_hibernate_timeout(ctx);
@@ -267,10 +267,11 @@ static bool cmd_idle_continue(struct client_command_context *cmd)
                return TRUE;
        }
        if (client->io == NULL) {
-               /* input is pending */
+               /* input is pending. add the io back and mark the input as
+                  pending. we can't safely read more input immediately here. */
                client->io = io_add_istream(client->input,
                                            idle_client_input, ctx);
-               (void)idle_client_input_more(ctx);
+               i_stream_set_input_pending(client->input, TRUE);
        }
        return FALSE;
 }