From: Tim Deegan <tim@xen.org>
Date: Thu, 12 Sep 2013 11:55:10 +0000 (+0100)
Subject: ehci-dbgp: avoid division by zero.
X-Git-Tag: archive/raspbian/4.8.0-1+rpi1~1^2~6374
X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=e58015acaf53b179847db94524fb2a9f4399b5e6;p=xen.git

ehci-dbgp: avoid division by zero.

Unlikely to ever see hardware reporting 0 ports, but might as well
fail gracefully if we do.

Coverity CID 1055266

Signed-off-by: Tim Deegan <tim@xen.org>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
---

diff --git a/xen/drivers/char/ehci-dbgp.c b/xen/drivers/char/ehci-dbgp.c
index 301eedf22e..b900d6092e 100644
--- a/xen/drivers/char/ehci-dbgp.c
+++ b/xen/drivers/char/ehci-dbgp.c
@@ -1094,6 +1094,9 @@ try_next_port:
     dbgp_printk("n_ports:    %u\n", n_ports);
     ehci_dbgp_status(dbgp, "");
 
+    if ( n_ports == 0 )
+        return -1;
+
     for ( i = 1; i <= n_ports; i++ )
     {
         portsc = readl(&dbgp->ehci_regs->port_status[i-1]);