The dvb demuxer code uses a 'struct timespec' to pass a timeout
as absolute time. This will cause problems on 32-bit architectures
in 2038 when time_t overflows, and it is racy with a concurrent
settimeofday() call.

This patch changes the code to use ktime_get() instead, using
the monotonic time base to avoid both the race and the overflow.

Signed-off-by: Arnd Bergmann <a...@arndb.de>
---
 drivers/media/dvb-core/demux.h     |  2 +-
 drivers/media/dvb-core/dmxdev.c    |  2 +-
 drivers/media/dvb-core/dvb_demux.c | 17 ++++++-----------
 drivers/media/dvb-core/dvb_demux.h |  4 ++--
 drivers/media/dvb-core/dvb_net.c   |  2 +-
 5 files changed, 11 insertions(+), 16 deletions(-)

diff --git a/drivers/media/dvb-core/demux.h b/drivers/media/dvb-core/demux.h
index 833191bcd810..d8e2b1213bef 100644
--- a/drivers/media/dvb-core/demux.h
+++ b/drivers/media/dvb-core/demux.h
@@ -92,7 +92,7 @@ struct dmx_ts_feed {
                    int type,
                    enum dmx_ts_pes pes_type,
                    size_t circular_buffer_size,
-                   struct timespec timeout);
+                   ktime_t timeout);
        int (*start_filtering) (struct dmx_ts_feed* feed);
        int (*stop_filtering) (struct dmx_ts_feed* feed);
 };
diff --git a/drivers/media/dvb-core/dmxdev.c b/drivers/media/dvb-core/dmxdev.c
index d0e3f9d85f34..0d20b379eeec 100644
--- a/drivers/media/dvb-core/dmxdev.c
+++ b/drivers/media/dvb-core/dmxdev.c
@@ -558,7 +558,7 @@ static int dvb_dmxdev_start_feed(struct dmxdev *dmxdev,
                                 struct dmxdev_filter *filter,
                                 struct dmxdev_feed *feed)
 {
-       struct timespec timeout = { 0 };
+       ktime_t timeout = ktime_set(0, 0);
        struct dmx_pes_filter_params *para = &filter->params.pes;
        dmx_output_t otype;
        int ret;
diff --git a/drivers/media/dvb-core/dvb_demux.c 
b/drivers/media/dvb-core/dvb_demux.c
index 6c7ff0cdcd32..f9f676112d30 100644
--- a/drivers/media/dvb-core/dvb_demux.c
+++ b/drivers/media/dvb-core/dvb_demux.c
@@ -399,28 +399,23 @@ static void dvb_dmx_swfilter_packet(struct dvb_demux 
*demux, const u8 *buf)
        int dvr_done = 0;
 
        if (dvb_demux_speedcheck) {
-               struct timespec cur_time, delta_time;
+               ktime_t cur_time;
                u64 speed_bytes, speed_timedelta;
 
                demux->speed_pkts_cnt++;
 
                /* show speed every SPEED_PKTS_INTERVAL packets */
                if (!(demux->speed_pkts_cnt % SPEED_PKTS_INTERVAL)) {
-                       cur_time = current_kernel_time();
+                       cur_time = ktime_get();
 
-                       if (demux->speed_last_time.tv_sec != 0 &&
-                                       demux->speed_last_time.tv_nsec != 0) {
-                               delta_time = timespec_sub(cur_time,
-                                               demux->speed_last_time);
+                       if (ktime_to_ns(demux->speed_last_time) != 0) {
                                speed_bytes = (u64)demux->speed_pkts_cnt
                                        * 188 * 8;
                                /* convert to 1024 basis */
                                speed_bytes = 1000 * div64_u64(speed_bytes,
                                                1024);
-                               speed_timedelta =
-                                       (u64)timespec_to_ns(&delta_time);
-                               speed_timedelta = div64_u64(speed_timedelta,
-                                               1000000); /* nsec -> usec */
+                               speed_timedelta = ktime_ms_delta(cur_time,
+                                                       demux->speed_last_time);
                                printk(KERN_INFO "TS speed %llu Kbits/sec \n",
                                                div64_u64(speed_bytes,
                                                        speed_timedelta));
@@ -667,7 +662,7 @@ out:
 
 static int dmx_ts_feed_set(struct dmx_ts_feed *ts_feed, u16 pid, int ts_type,
                           enum dmx_ts_pes pes_type,
-                          size_t circular_buffer_size, struct timespec timeout)
+                          size_t circular_buffer_size, ktime_t timeout)
 {
        struct dvb_demux_feed *feed = (struct dvb_demux_feed *)ts_feed;
        struct dvb_demux *demux = feed->demux;
diff --git a/drivers/media/dvb-core/dvb_demux.h 
b/drivers/media/dvb-core/dvb_demux.h
index ae7fc33c3231..5ed3cab4ad28 100644
--- a/drivers/media/dvb-core/dvb_demux.h
+++ b/drivers/media/dvb-core/dvb_demux.h
@@ -83,7 +83,7 @@ struct dvb_demux_feed {
        u8 *buffer;
        int buffer_size;
 
-       struct timespec timeout;
+       ktime_t timeout;
        struct dvb_demux_filter *filter;
 
        int ts_type;
@@ -134,7 +134,7 @@ struct dvb_demux {
 
        uint8_t *cnt_storage; /* for TS continuity check */
 
-       struct timespec speed_last_time; /* for TS speed check */
+       ktime_t speed_last_time; /* for TS speed check */
        uint32_t speed_pkts_cnt; /* for TS speed check */
 };
 
diff --git a/drivers/media/dvb-core/dvb_net.c b/drivers/media/dvb-core/dvb_net.c
index b81e026edab3..df3ba15c007e 100644
--- a/drivers/media/dvb-core/dvb_net.c
+++ b/drivers/media/dvb-core/dvb_net.c
@@ -998,7 +998,7 @@ static int dvb_net_feed_start(struct net_device *dev)
                netdev_dbg(dev, "start filtering\n");
                priv->secfeed->start_filtering(priv->secfeed);
        } else if (priv->feedtype == DVB_NET_FEEDTYPE_ULE) {
-               struct timespec timeout = { 0, 10000000 }; // 10 msec
+               ktime_t timeout = ns_to_ktime(10 * NSEC_PER_MSEC);
 
                /* we have payloads encapsulated in TS */
                netdev_dbg(dev, "alloc tsfeed\n");
-- 
2.1.0.rc2

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