From a08c7c68f702e2a2797a4035b6c0a756c4886c26 Mon Sep 17 00:00:00 2001 From: Brian Rogers Date: Wed, 22 Sep 2010 08:06:43 -0300 Subject: 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 Acked-by: Jarod Wilson Signed-off-by: Mauro Carvalho Chehab --- drivers/media/IR/ir-sysfs.c | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) (limited to 'drivers/media/IR') diff --git a/drivers/media/IR/ir-sysfs.c b/drivers/media/IR/ir-sysfs.c index 96dafc425c8e..46d42467f9b4 100644 --- a/drivers/media/IR/ir-sysfs.c +++ b/drivers/media/IR/ir-sysfs.c @@ -67,13 +67,14 @@ static ssize_t show_protocols(struct device *d, 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 @@ static ssize_t store_protocols(struct device *d, 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 @@ static ssize_t store_protocols(struct device *d, } } - 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); -- cgit v1.2.3