[media] rc: Set rdev before irq setup

This fixes a problem in fintek-cir and nuvoton-cir where the
irq handler would trigger during module load before the rdev member was
set, causing a NULL pointer crash.
It seems this crash is very reproducible (just bombard the receiver with
IR signals during module load), probably because when request_irq is
called, any pending intterupt is handled immediately, before
request_irq returns and rdev can be set.
This same crash was supposed to be fixed by commit
9ef449c6b31bb6a8e6dedc24de475a3b8c79be20 ("[media] rc: Postpone ISR
registration"), but the crash was still observed on the nuvoton-cir
driver.
This commit was tested on nuvoton-cir only.

Cc: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Matthijs Kooijman <matthijs@stdin.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

2 files changed, 5 insertions, 2 deletions

diff --git a/drivers/media/rc/fintek-cir.c b/drivers/media/rc/fintek-cir.c
index 3d5e57cacf31..5eefe65760a4 100644
--- a/drivers/media/rc/fintek-cir.c
+++ b/drivers/media/rc/fintek-cir.c
@@ -557,6 +557,8 @@ static int fintek_probe(struct pnp_dev *pdev, const struct pnp_device_id *dev_id
         /* rx resolution is hardwired to 50us atm, 1, 25, 100 also possible */
         rdev->rx_resolution = US_TO_NS(CIR_SAMPLE_PERIOD);
 
+        fintek->rdev = rdev;
+
         ret = -EBUSY;
         /* now claim resources */
         if (!request_region(fintek->cir_addr,
@@ -572,7 +574,7 @@ static int fintek_probe(struct pnp_dev *pdev, const struct pnp_device_id *dev_id
                 goto exit_free_irq;
 
         device_init_wakeup(&pdev->dev, true);
-        fintek->rdev = rdev;
+
         fit_pr(KERN_NOTICE, "driver has been successfully loaded\n");
         if (debug)
                 cir_dump_regs(fintek);
diff --git a/drivers/media/rc/nuvoton-cir.c b/drivers/media/rc/nuvoton-cir.c
index 3477e231c182..c6441e690dd4 100644
--- a/drivers/media/rc/nuvoton-cir.c
+++ b/drivers/media/rc/nuvoton-cir.c
@@ -1065,6 +1065,7 @@ static int nvt_probe(struct pnp_dev *pdev, const struct pnp_device_id *dev_id)
         /* tx bits */
         rdev->tx_resolution = XYZ;
 #endif
+        nvt->rdev = rdev;
 
         ret = -EBUSY;
         /* now claim resources */
@@ -1089,7 +1090,7 @@ static int nvt_probe(struct pnp_dev *pdev, const struct pnp_device_id *dev_id)
                 goto exit_free_wake_irq;
 
         device_init_wakeup(&pdev->dev, true);
-        nvt->rdev = rdev;
+
         nvt_pr(KERN_NOTICE, "driver has been successfully loaded\n");
         if (debug) {
                 cir_dump_regs(nvt);