From 860b7c398a744c1eef42a59b661e870aca12d9be Mon Sep 17 00:00:00 2001 From: H Hartley Sweeten Date: Thu, 17 Apr 2014 10:07:46 -0700 Subject: [PATCH] staging: comedi: drivers: core validates chanlist_len max The comedi core checks if the (cmd->chanlist_len > s->len_chanlist) when the comedi_cmd is copied from user to kernel space by __comedi_get_user_cmd(). If so, the core returns -EINVAL and will not call the subdevice (*do_cmdtest) and (*do_cmd). Remove the unnecessary "max" checks in the comedi driver (*do_cmdtest) and helper functions. Signed-off-by: H Hartley Sweeten Reviewed-by: Ian Abbott Signed-off-by: Greg Kroah-Hartman --- drivers/staging/comedi/drivers/addi-data/hwdrv_apci3120.c | 3 --- drivers/staging/comedi/drivers/adl_pci9118.c | 2 -- drivers/staging/comedi/drivers/pcl812.c | 1 - drivers/staging/comedi/drivers/rtd520.c | 4 ---- 4 files changed, 10 deletions(-) diff --git a/drivers/staging/comedi/drivers/addi-data/hwdrv_apci3120.c b/drivers/staging/comedi/drivers/addi-data/hwdrv_apci3120.c index 70e8f426285c..66c24e41d0ff 100644 --- a/drivers/staging/comedi/drivers/addi-data/hwdrv_apci3120.c +++ b/drivers/staging/comedi/drivers/addi-data/hwdrv_apci3120.c @@ -734,7 +734,6 @@ static int apci3120_ai_cmdtest(struct comedi_device *dev, struct comedi_subdevice *s, struct comedi_cmd *cmd) { - const struct addi_board *this_board = comedi_board(dev); int err = 0; /* Step 1 : check if triggers are trivially valid */ @@ -779,8 +778,6 @@ static int apci3120_ai_cmdtest(struct comedi_device *dev, } err |= cfc_check_trigger_arg_min(&cmd->chanlist_len, 1); - err |= cfc_check_trigger_arg_max(&cmd->chanlist_len, - this_board->i_AiChannelList); if (cmd->stop_src == TRIG_COUNT) err |= cfc_check_trigger_arg_min(&cmd->stop_arg, 1); diff --git a/drivers/staging/comedi/drivers/adl_pci9118.c b/drivers/staging/comedi/drivers/adl_pci9118.c index b6abef6ceab7..53bbc59f6176 100644 --- a/drivers/staging/comedi/drivers/adl_pci9118.c +++ b/drivers/staging/comedi/drivers/adl_pci9118.c @@ -1259,8 +1259,6 @@ static int pci9118_ai_cmdtest(struct comedi_device *dev, err |= cfc_check_trigger_arg_is(&cmd->stop_arg, 0); err |= cfc_check_trigger_arg_min(&cmd->chanlist_len, 1); - err |= cfc_check_trigger_arg_max(&cmd->chanlist_len, - this_board->n_aichanlist); err |= cfc_check_trigger_arg_min(&cmd->scan_end_arg, cmd->chanlist_len); diff --git a/drivers/staging/comedi/drivers/pcl812.c b/drivers/staging/comedi/drivers/pcl812.c index 5cc01fe45cf2..0cf115e54308 100644 --- a/drivers/staging/comedi/drivers/pcl812.c +++ b/drivers/staging/comedi/drivers/pcl812.c @@ -761,7 +761,6 @@ static int pcl812_ai_cmdtest(struct comedi_device *dev, err |= cfc_check_trigger_arg_is(&cmd->convert_arg, 0); err |= cfc_check_trigger_arg_min(&cmd->chanlist_len, 1); - err |= cfc_check_trigger_arg_max(&cmd->chanlist_len, MAX_CHANLIST_LEN); err |= cfc_check_trigger_arg_is(&cmd->scan_end_arg, cmd->chanlist_len); if (cmd->stop_src == TRIG_COUNT) diff --git a/drivers/staging/comedi/drivers/rtd520.c b/drivers/staging/comedi/drivers/rtd520.c index cd3fdf973bdd..1b1c166c8e9b 100644 --- a/drivers/staging/comedi/drivers/rtd520.c +++ b/drivers/staging/comedi/drivers/rtd520.c @@ -891,10 +891,6 @@ static int rtd_ai_cmdtest(struct comedi_device *dev, /* step 4: fix up any arguments */ - if (cmd->chanlist_len > RTD_MAX_CHANLIST) { - cmd->chanlist_len = RTD_MAX_CHANLIST; - err++; - } if (cmd->scan_begin_src == TRIG_TIMER) { tmp = cmd->scan_begin_arg; rtd_ns_to_timer(&cmd->scan_begin_arg, -- 2.39.2