netdev - v4 [PATCH net-next 4/7] ipv6: Check return of dev_set

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <486C4640.8060009@cn.fujitsu.com>
Date:	Thu, 03 Jul 2008 11:23:44 +0800
From:	Wang Chen <wangchen@...fujitsu.com>
To:	"David S. Miller" <davem@...emloft.net>
CC:	Patrick McHardy <kaber@...sh.net>, NETDEV <netdev@...r.kernel.org>,
	YOSHIFUJI Hideaki <yoshfuji@...ux-ipv6.org>
Subject: v4 [PATCH net-next 4/7] ipv6: Check return of dev_set_allmulti

Patrick McHardy said the following on 2008-7-2 20:54:
>> +    dev_close(dev);
>> +    unregister_netdevice(dev);
> 
> dev_close is already performed by unregister_netdevice.
> 
>> +    free_netdev(dev);
> 
> This is a double free, the device uses free_netdev as destructor.
> 

Patrick, thanks for your time.
I am so shame for being unware such idiot mistake.

v3->v4
As Patrick said, unregister_netdevice() can do all unwind job
for ip6mr_reg_vif().

allmulti might overflow.
Commit: "netdevice: Fix promiscuity and allmulti overflow" in net-next makes
dev_set_promiscuity/allmulti return error number if overflow happened.

Here, we check the positive increment for allmulti to get error return.

Signed-off-by: Wang Chen <wangchen@...fujitsu.com>
---
diff --git a/net/ipv6/ip6mr.c b/net/ipv6/ip6mr.c
index 1479618..6cd286d 100644
--- a/net/ipv6/ip6mr.c
+++ b/net/ipv6/ip6mr.c
@@ -603,6 +603,7 @@ static int mif6_add(struct mif6ctl *vifc, int mrtsock)
 	int vifi = vifc->mif6c_mifi;
 	struct mif_device *v = &vif6_table[vifi];
 	struct net_device *dev;
+	int err;
 
 	/* Is vif busy ? */
 	if (MIF_EXISTS(vifi))
@@ -620,6 +621,11 @@ static int mif6_add(struct mif6ctl *vifc, int mrtsock)
 		dev = ip6mr_reg_vif();
 		if (!dev)
 			return -ENOBUFS;
+		err = dev_set_allmulti(dev, 1);
+		if (err) {
+			unregister_netdevice(dev);
+			return err;
+		}
 		break;
 #endif
 	case 0:
@@ -627,13 +633,14 @@ static int mif6_add(struct mif6ctl *vifc, int mrtsock)
 		if (!dev)
 			return -EADDRNOTAVAIL;
 		dev_put(dev);
+		err = dev_set_allmulti(dev, 1);
+		if (err)
+			return err;
 		break;
 	default:
 		return -EINVAL;
 	}
 
-	dev_set_allmulti(dev, 1);
-
 	/*
 	 *	Fill in the VIF structures
 	 */

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html