[PATCH] USB: negative index in drivers/usb/host/isp116x-hcd.c
From: Eric Sesterhenn <snakebyte@gmx.de>
This fixes coverity Bug #390.
With the following code
ret = ep->branch = balance(isp116x, ep->period, ep->load);
if (ret < 0)
goto fail;
the problem is that ret and balance are of the type int, and ep->branch is u16.
so the int balance() returns gets reduced to u16 and then converted to an int again,
which removes the sign. Maybe the following little c program can explain it better:
diff --git a/drivers/usb/host/isp116x-hcd.c b/drivers/usb/host/isp116x-hcd.c
index e99210b..c5e2240 100644
--- a/drivers/usb/host/isp116x-hcd.c
+++ b/drivers/usb/host/isp116x-hcd.c
@@ -781,7 +781,7 @@
if (ep->branch < PERIODIC_SIZE)
break;
- ret = ep->branch = balance(isp116x, ep->period, ep->load);
+ ep->branch = ret = balance(isp116x, ep->period, ep->load);
if (ret < 0)
goto fail;
ret = 0;