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 <hswee...@visionengravers.com>
Cc: Ian Abbott <abbo...@mev.co.uk>
Cc: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
 drivers/staging/comedi/drivers/addi-data/hwdrv_apci3120.c | 3 ---
 drivers/staging/comedi/drivers/adl_pci9118.c              | 2 --
 drivers/staging/comedi/drivers/me4000.c                   | 6 ------
 drivers/staging/comedi/drivers/ni_labpc.c                 | 8 --------
 drivers/staging/comedi/drivers/pcl812.c                   | 1 -
 drivers/staging/comedi/drivers/rtd520.c                   | 4 ----
 6 files changed, 24 deletions(-)

diff --git a/drivers/staging/comedi/drivers/addi-data/hwdrv_apci3120.c 
b/drivers/staging/comedi/drivers/addi-data/hwdrv_apci3120.c
index 70e8f42..66c24e4 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 b6abef6..53bbc59 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/me4000.c 
b/drivers/staging/comedi/drivers/me4000.c
index f02b31b..bd03a15 100644
--- a/drivers/staging/comedi/drivers/me4000.c
+++ b/drivers/staging/comedi/drivers/me4000.c
@@ -611,12 +611,6 @@ static int ai_check_chanlist(struct comedi_device *dev,
                return -EINVAL;
        }
 
-       /* Check the channel list size */
-       if (cmd->chanlist_len > ME4000_AI_CHANNEL_LIST_COUNT) {
-               dev_err(dev->class_dev, "Channel list is to large\n");
-               return -EINVAL;
-       }
-
        /* Check the pointer */
        if (!cmd->chanlist) {
                dev_err(dev->class_dev, "NULL pointer to channel list\n");
diff --git a/drivers/staging/comedi/drivers/ni_labpc.c 
b/drivers/staging/comedi/drivers/ni_labpc.c
index f4216e8..c33b9fc 100644
--- a/drivers/staging/comedi/drivers/ni_labpc.c
+++ b/drivers/staging/comedi/drivers/ni_labpc.c
@@ -558,14 +558,6 @@ static int labpc_ai_chanlist_invalid(const struct 
comedi_device *dev,
        if (mode == MODE_SINGLE_CHAN)
                return 0;
 
-       if (mode == MODE_SINGLE_CHAN_INTERVAL) {
-               if (cmd->chanlist_len > 0xff) {
-                       comedi_error(dev,
-                                    "ni_labpc: chanlist too long for single 
channel interval mode\n");
-                       return 1;
-               }
-       }
-
        channel = CR_CHAN(cmd->chanlist[0]);
        range = CR_RANGE(cmd->chanlist[0]);
        aref = CR_AREF(cmd->chanlist[0]);
diff --git a/drivers/staging/comedi/drivers/pcl812.c 
b/drivers/staging/comedi/drivers/pcl812.c
index 5cc01fe..0cf115e 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 cd3fdf9..1b1c166 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,
-- 
1.8.5.2

_______________________________________________
devel mailing list
de...@linuxdriverproject.org
http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel

Reply via email to