[PATCH] Fix data access out of array bounds

[Karsten Keil <kkeil@suse.de>]

Fix against access random data bytes outside the
dev->chanmap array. Thanks to Oliver Neukum for
pointing me to this issue.
Patch is against 2.6.23-rc9-git6

Signed-off-by: Karsten Keil <kkeil@suse.de>
---
 drivers/isdn/i4l/isdn_common.c |    5 +++--
 1 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/isdn/i4l/isdn_common.c b/drivers/isdn/i4l/isdn_common.c
index ec5f404..4910bca 100644
--- a/drivers/isdn/i4l/isdn_common.c
+++ b/drivers/isdn/i4l/isdn_common.c
@@ -1135,7 +1135,7 @@ isdn_read(struct file *file, char __user *buf, size_t count, loff_t * off)
 			if (count > dev->drv[drvidx]->stavail)
 				count = dev->drv[drvidx]->stavail;
 			len = dev->drv[drvidx]->interface->readstat(buf, count,
-						drvidx, isdn_minor2chan(minor));
+				drvidx, isdn_minor2chan(minor - ISDN_MINOR_CTRL));
 			if (len < 0) {
 				retval = len;
 				goto out;
@@ -1207,7 +1207,8 @@ isdn_write(struct file *file, const char __user *buf, size_t count, loff_t * off
 		 */
 		if (dev->drv[drvidx]->interface->writecmd)
 			retval = dev->drv[drvidx]->interface->
-				writecmd(buf, count, drvidx, isdn_minor2chan(minor));
+				writecmd(buf, count, drvidx,
+				isdn_minor2chan(minor - ISDN_MINOR_CTRL));
 		else
 			retval = count;
 		goto out;



-- 
Karsten Keil
SuSE Labs
ISDN and VOIP development
SUSE LINUX Products GmbH, Maxfeldstr.5 90409 Nuernberg, GF: Markus Rex, HRB 16746 (AG Nuernberg)