From cb81159ce49380d39c80f803353784633b8f306c Mon Sep 17 00:00:00 2001

From: "S. Fan" <sfanxiang@gmail.com>

Date: Mon, 31 Jul 2017 05:10:10 -0500

Subject: [PATCH] rfkill: fix erroneous behavior when polling the udev monitor

 (#6489)

Comparing udev_device_get_sysname(device) and sysname will always return

true. We need to check the device received from udev monitor instead.

Also, fd_wait_for_event() sometimes never exits. Better set a timeout

here.

(cherry picked from commit 8ec1a07998758f6a85f3ea5bf2ed14d87609398f)

---

 src/rfkill/rfkill.c | 8 ++++++--

 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/src/rfkill/rfkill.c b/src/rfkill/rfkill.c

index c0f138b4f4..470853d1d2 100644

--- a/src/rfkill/rfkill.c

+++ b/src/rfkill/rfkill.c

@@ -138,17 +138,21 @@ static int wait_for_initialized(

         for (;;) {

                 _cleanup_udev_device_unref_ struct udev_device *t = NULL;

-                r = fd_wait_for_event(watch_fd, POLLIN, USEC_INFINITY);

+                r = fd_wait_for_event(watch_fd, POLLIN, EXIT_USEC);

                 if (r == -EINTR)

                         continue;

                 if (r < 0)

                         return log_error_errno(r, "Failed to watch udev monitor: %m");

+                if (r == 0) {

+                        log_error("Timed out wating for udev monitor.");

+                        return -ETIMEDOUT;

+                }

                 t = udev_monitor_receive_device(monitor);

                 if (!t)

                         continue;

-                if (streq_ptr(udev_device_get_sysname(device), sysname)) {

+                if (streq_ptr(udev_device_get_sysname(t), sysname)) {

                         *ret = udev_device_ref(t);

                         return 0;

                 }