V4L/DVB: ir-core: Fix null dereferences in the protocols sysfs interface
For some cards, ir_dev->props and ir_dev->raw are both NULL. These cards are
using built-in IR decoding instead of raw, and can't easily be made to switch
protocols.
So upon reading /sys/class/rc/rc?/protocols on such a card, return 'builtin' as
the supported and enabled protocol. Return -EINVAL on any attempts to change
the protocol. And most important of all, don't crash.
Signed-off-by: Brian Rogers <brian@xyzw.org>
Acked-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/IR/ir-sysfs.c b/drivers/media/IR/ir-sysfs.c
index 96dafc4..46d4246 100644
--- a/drivers/media/IR/ir-sysfs.c
+++ b/drivers/media/IR/ir-sysfs.c
@@ -67,13 +67,14 @@
char *tmp = buf;
int i;
- if (ir_dev->props->driver_type == RC_DRIVER_SCANCODE) {
+ if (ir_dev->props && ir_dev->props->driver_type == RC_DRIVER_SCANCODE) {
enabled = ir_dev->rc_tab.ir_type;
allowed = ir_dev->props->allowed_protos;
- } else {
+ } else if (ir_dev->raw) {
enabled = ir_dev->raw->enabled_protocols;
allowed = ir_raw_get_allowed_protocols();
- }
+ } else
+ return sprintf(tmp, "[builtin]\n");
IR_dprintk(1, "allowed - 0x%llx, enabled - 0x%llx\n",
(long long)allowed,
@@ -121,10 +122,14 @@
int rc, i, count = 0;
unsigned long flags;
- if (ir_dev->props->driver_type == RC_DRIVER_SCANCODE)
+ if (ir_dev->props && ir_dev->props->driver_type == RC_DRIVER_SCANCODE)
type = ir_dev->rc_tab.ir_type;
- else
+ else if (ir_dev->raw)
type = ir_dev->raw->enabled_protocols;
+ else {
+ IR_dprintk(1, "Protocol switching not supported\n");
+ return -EINVAL;
+ }
while ((tmp = strsep((char **) &data, " \n")) != NULL) {
if (!*tmp)
@@ -185,7 +190,7 @@
}
}
- if (ir_dev->props->driver_type == RC_DRIVER_SCANCODE) {
+ if (ir_dev->props && ir_dev->props->driver_type == RC_DRIVER_SCANCODE) {
spin_lock_irqsave(&ir_dev->rc_tab.lock, flags);
ir_dev->rc_tab.ir_type = type;
spin_unlock_irqrestore(&ir_dev->rc_tab.lock, flags);