From: Nick Porter <nick@portercomputing.co.uk>
Date: Tue, 15 Jun 2021 21:24:28 +0000 (+0100)
Subject: v4: Amend async exec calls to ensure both child process exited and fd callbacks have... 
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=325c1710171e7df482b614d9b9f85df2ea34cc9e;p=thirdparty%2Ffreeradius-server.git

v4: Amend async exec calls to ensure both child process exited and fd callbacks have completed (#4113)

* Improve debug message - program has exited, not necessarily failed

* Report all output from exec

* Only resume unlang execution when both the child process has...

... exited and the fd event has seen an EOF
---

diff --git a/src/lib/server/exec.c b/src/lib/server/exec.c
index 35c93573ad0..cf0f3b454f2 100644
--- a/src/lib/server/exec.c
+++ b/src/lib/server/exec.c
@@ -932,7 +932,7 @@ static void exec_waitpid(UNUSED fr_event_list_t *el, UNUSED pid_t pid, int statu
 	request_t	*request = exec->request;
 
 	if (WIFEXITED(status)) {
-		RDEBUG("Program failed with status code %d", WEXITSTATUS(status));
+		RDEBUG("Program exited with status code %d", WEXITSTATUS(status));
 		exec->status = WEXITSTATUS(status);
 	} else if (WIFSIGNALED(status)) {
 		RDEBUG("Program exited due to signal with status code %d", WTERMSIG(status));
@@ -948,6 +948,10 @@ static void exec_waitpid(UNUSED fr_event_list_t *el, UNUSED pid_t pid, int statu
 	 *	"pipe has been closed" signal
 	 */
 	if (exec->stdout_fd >= 0) {
+		if (exec->stdout_used) {
+			RDEBUG("Program exited without EOF being read");
+			return;
+		}
 		(void) fr_event_fd_delete(exec->request->el, exec->stdout_fd, FR_EVENT_FILTER_IO);
 		close(exec->stdout_fd);
 		exec->stdout_fd = -1;
@@ -1001,7 +1005,7 @@ static void exec_timeout(
 /*
  *	Callback to read stdout from an exec into the pre-prepared extensible sbuff
  */
-static void exec_stdout_read(UNUSED fr_event_list_t *el, int fd, UNUSED int flags, void *uctx) {
+static void exec_stdout_read(UNUSED fr_event_list_t *el, int fd, int flags, void *uctx) {
 	fr_exec_state_t		*exec = uctx;
 	request_t		*request = exec->request;
 	ssize_t			data_len, remaining;
@@ -1046,6 +1050,24 @@ static void exec_stdout_read(UNUSED fr_event_list_t *el, int fd, UNUSED int flag
 		fr_sbuff_advance(&exec->stdout_buff, data_len);
 	} while (remaining == data_len);	/* If process returned maximum output, loop again */
 
+	if (flags & EV_EOF) {
+		/*
+		 *	We've received EOF - so the process has finished writing
+		 *	Remove event and tidy up
+		 */
+		(void) fr_event_fd_delete(exec->request->el, fd, FR_EVENT_FILTER_IO);
+		close(fd);
+		exec->stdout_fd = -1;
+
+		if (exec->pid == 0) {
+			/*
+			 *	Child has already exited - unlang can resume
+			 */
+			if (exec->ev) fr_event_timer_delete(&exec->ev);
+			unlang_interpret_mark_runnable(exec->request);
+		}
+	}
+
 	/*
 	 *	Only print if we got additional data
 	 */
diff --git a/src/modules/rlm_exec/rlm_exec.c b/src/modules/rlm_exec/rlm_exec.c
index 7a7081c2148..b63c09d2954 100644
--- a/src/modules/rlm_exec/rlm_exec.c
+++ b/src/modules/rlm_exec/rlm_exec.c
@@ -379,7 +379,7 @@ static unlang_action_t mod_exec_wait_resume(rlm_rcode_t *p_result, module_ctx_t
 		fr_pair_list_t vps, *output_pairs;
 		fr_value_box_t *box = fr_dlist_head(&m->box);
 
-		RDEBUG("EXEC GOT -- %pV", box);
+		RDEBUG("EXEC GOT -- %pM", &m->box);
 
 		fr_pair_list_init(&vps);
 		output_pairs = tmpl_list_head(request, inst->output_list);