From d22700fc5d5098c683b465ea0fede43803fd4d6b Mon Sep 17 00:00:00 2001

From: Reid wahl <nrwahl@protonmail.com>

Date: Tue, 7 Jul 2020 02:18:09 -0700

Subject: [PATCH] azure-lb: Don't redirect nc listener output to pidfile

The `lb_start()` function spawns an `nc` listener background process

and echoes the resulting pid to `$pidfile`. Due to a bug in the

redirection, all future data received by the `nc` process is also

appended to `$pidfile`.

If binary data is received later and appended to `$pidfile`, the

monitor operation fails when `grep` searches the now-binary file.

```

line 97: kill: Binary: arguments must be process or job IDs ]

line 97: kill: file: arguments must be process or job IDs ]

line 97: kill: /var/run/nc_PF2_02.pid: arguments must be process or job

    IDs ]

line 97: kill: matches: arguments must be process or job IDs ]

```

Then the start operation fails during recovery. `lb_start()` spawns a

new `nc` process, but the old process is still running and using the

configured port.

```

nc_PF2_02_start_0:777:stderr [ Ncat: bind to :::62502: Address

    already in use. QUITTING. ]

```

This patch fixes the issue by removing the `nc &` command from the

section whose output gets redirected to `$pidfile`. Now, only the `nc`

PID is echoed to `$pidfile`.

Resolves: RHBZ#1850778

Resolves: RHBZ#1850779

---

 heartbeat/azure-lb | 3 ++-

 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/heartbeat/azure-lb b/heartbeat/azure-lb

index 05c134514..05755d778 100755

--- a/heartbeat/azure-lb

+++ b/heartbeat/azure-lb

@@ -113,7 +113,8 @@ lb_start() {

 	if ! lb_monitor; then

 		ocf_log debug "Starting $process: $cmd"

 		# Execute the command as created above

-		eval "$cmd & echo \$!" > $pidfile

+		$cmd &

+		echo $! > $pidfile

 		if lb_monitor; then

 			ocf_log debug "$process: $cmd started successfully, calling monitor"

 			lb_monitor