submission: submission-backend-relay - Abort client command when server command is...

This fixes segmentation faults occurring when server commands are aborted
(connection is closed).

diff --git a/src/submission/submission-backend-relay.c b/src/submission/submission-backend-relay.c
index b77005e5d0c93f16c48c6b830829a5be841bb978..c8da8f0323b65d2f4efb8e1454f925aa5ab64e99 100644 (file)
--- a/src/submission/submission-backend-relay.c
+++ b/src/submission/submission-backend-relay.c
@@ -227,6 +227,15 @@ struct relay_cmd_helo_context {
        struct smtp_client_command *cmd_relayed;
 };
 
+static void
+relay_cmd_helo_destroy(struct smtp_server_cmd_ctx *cmd ATTR_UNUSED,
+                      struct relay_cmd_helo_context *helo_cmd)
+{
+       i_assert(helo_cmd != NULL);
+       if (helo_cmd->cmd_relayed != NULL)
+               smtp_client_command_abort(&helo_cmd->cmd_relayed);
+}
+
 static void
 relay_cmd_helo_update_xclient(struct submission_backend_relay *backend,
                              struct smtp_server_cmd_helo *data)
@@ -314,6 +323,8 @@ backend_relay_cmd_helo(struct submission_backend *_backend,
        /* This is not the first HELO/EHLO; just relay a RSET command */
        smtp_server_command_add_hook(cmd->cmd, SMTP_SERVER_COMMAND_HOOK_NEXT,
                                     relay_cmd_helo_start, helo_cmd);
+       smtp_server_command_add_hook(cmd->cmd, SMTP_SERVER_COMMAND_HOOK_DESTROY,
+                                    relay_cmd_helo_destroy, helo_cmd);
        helo_cmd->cmd_relayed = smtp_client_command_rset_submit(
                backend->conn, 0, relay_cmd_helo_callback, helo_cmd);
        return 0;
@@ -560,6 +571,15 @@ struct relay_cmd_rset_context {
        struct smtp_client_command *cmd_relayed;
 };
 
+static void
+relay_cmd_rset_destroy(struct smtp_server_cmd_ctx *cmd ATTR_UNUSED,
+                      struct relay_cmd_rset_context *rset_cmd)
+{
+       i_assert(rset_cmd != NULL);
+       if (rset_cmd->cmd_relayed != NULL)
+               smtp_client_command_abort(&rset_cmd->cmd_relayed);
+}
+
 static void
 relay_cmd_rset_callback(const struct smtp_reply *relay_reply,
                        struct relay_cmd_rset_context *rset_cmd)
@@ -600,6 +620,9 @@ backend_relay_cmd_rset(struct submission_backend *_backend,
                                              rset_cmd);
        } else {
                /* RSET alone */
+               smtp_server_command_add_hook(cmd->cmd,
+                                            SMTP_SERVER_COMMAND_HOOK_DESTROY,
+                                            relay_cmd_rset_destroy, rset_cmd);
                rset_cmd->cmd_relayed = smtp_client_command_rset_submit(
                        backend->conn, 0, relay_cmd_rset_callback, rset_cmd);
        }
@@ -766,6 +789,15 @@ struct relay_cmd_vrfy_context {
        struct smtp_client_command *cmd_relayed;
 };
 
+static void
+relay_cmd_vrfy_destroy(struct smtp_server_cmd_ctx *cmd ATTR_UNUSED,
+                      struct relay_cmd_vrfy_context *vrfy_cmd)
+{
+       i_assert(vrfy_cmd != NULL);
+       if (vrfy_cmd->cmd_relayed != NULL)
+               smtp_client_command_abort(&vrfy_cmd->cmd_relayed);
+}
+
 static void
 relay_cmd_vrfy_callback(const struct smtp_reply *relay_reply,
                        struct relay_cmd_vrfy_context *vrfy_cmd)
@@ -827,6 +859,8 @@ backend_relay_cmd_vrfy(struct submission_backend *_backend,
        vrfy_cmd->backend = backend;
        vrfy_cmd->cmd = cmd;
 
+       smtp_server_command_add_hook(cmd->cmd, SMTP_SERVER_COMMAND_HOOK_DESTROY,
+                                    relay_cmd_vrfy_destroy, vrfy_cmd);
        vrfy_cmd->cmd_relayed = smtp_client_command_vrfy_submit(
                backend->conn, 0, param, relay_cmd_vrfy_callback, vrfy_cmd);
        return 0;
@@ -844,6 +878,15 @@ struct relay_cmd_noop_context {
        struct smtp_client_command *cmd_relayed;
 };
 
+static void
+relay_cmd_noop_destroy(struct smtp_server_cmd_ctx *cmd ATTR_UNUSED,
+                      struct relay_cmd_noop_context *noop_cmd)
+{
+       i_assert(noop_cmd != NULL);
+       if (noop_cmd->cmd_relayed != NULL)
+               smtp_client_command_abort(&noop_cmd->cmd_relayed);
+}
+
 static void
 relay_cmd_noop_callback(const struct smtp_reply *relay_reply,
                        struct relay_cmd_noop_context *noop_cmd)
@@ -879,6 +922,8 @@ backend_relay_cmd_noop(struct submission_backend *_backend,
        noop_cmd->backend = backend;
        noop_cmd->cmd = cmd;
 
+       smtp_server_command_add_hook(cmd->cmd, SMTP_SERVER_COMMAND_HOOK_DESTROY,
+                                    relay_cmd_noop_destroy, noop_cmd);
        noop_cmd->cmd_relayed = smtp_client_command_noop_submit(
                backend->conn, 0, relay_cmd_noop_callback, noop_cmd);
        return 0;