Messages in this thread Patch in this message | | | Date | Mon, 31 Mar 2003 10:34:51 +0900 (JST) | Subject | Re: [PATCH] IPv6: Don't assign a same IPv6 address on a same interface | From | YOSHIFUJI Hideaki / 吉藤英明 <> |
| |
In article <20030331.033524.114862210.yoshfuji@linux-ipv6.org> (at Mon, 31 Mar 2003 03:35:24 +0900 (JST)), YOSHIFUJI Hideaki / 吉藤英明 <yoshfuji@linux-ipv6.org> says:
> In article <20030330163656.GA18645@ferrara.linux.it> (at Sun, 30 Mar 2003 18:36:56 +0200), Simone Piunno <pioppo@ferrara.linux.it> says: > > > - locking inside ipv6_add_addr() is simpler and more linear but > > semantically wrong because you're unable to tell the user why his > > "ip addr add" failed. E.g. you answer ENOBUFS instead of EEXIST. > > We don't want to create duplicate address in any case. > ipv6_add_addr() IS right place. > And, we can return error code by using IS_ERR() etc. > I'll fix this.
Here's the revised patch. Thank you.
Index: net/ipv6/addrconf.c =================================================================== RCS file: /cvsroot/usagi/usagi-backport/linux25/net/ipv6/addrconf.c,v retrieving revision 1.1.1.9 retrieving revision 1.1.1.9.2.6 diff -u -r1.1.1.9 -r1.1.1.9.2.6 --- net/ipv6/addrconf.c 25 Mar 2003 04:33:45 -0000 1.1.1.9 +++ net/ipv6/addrconf.c 30 Mar 2003 18:51:29 -0000 1.1.1.9.2.6 @@ -30,6 +30,8 @@ * address validation timer. * YOSHIFUJI Hideaki @USAGI : Privacy Extensions (RFC3041) * support. + * Yuji SEKIYA @USAGI : Don't assign a same IPv6 + * address on a same interface. */ #include <linux/config.h> @@ -126,6 +128,8 @@ static void addrconf_rs_timer(unsigned long data); static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa); +static int ipv6_chk_same_addr(const struct in6_addr *addr, struct net_device *dev); + static struct notifier_block *inet6addr_chain; struct ipv6_devconf ipv6_devconf = @@ -492,12 +496,23 @@ { struct inet6_ifaddr *ifa; int hash; + static spinlock_t lock = SPIN_LOCK_UNLOCKED; + + spin_lock_bh(&lock); + + /* Ignore adding duplicate addresses on an interface */ + if (ipv6_chk_same_addr(addr, idev->dev)) { + spin_unlock_bh(&lock); + ADBG(("ipv6_add_addr: already assigned\n")); + return ERR_PTR(-EEXIST); + } ifa = kmalloc(sizeof(struct inet6_ifaddr), GFP_ATOMIC); if (ifa == NULL) { + spin_unlock_bh(&lock); ADBG(("ipv6_add_addr: malloc failed\n")); - return NULL; + return ERR_PTR(-ENOBUFS); } memset(ifa, 0, sizeof(struct inet6_ifaddr)); @@ -513,8 +528,9 @@ read_lock(&addrconf_lock); if (idev->dead) { read_unlock(&addrconf_lock); + spin_unlock_bh(&lock); kfree(ifa); - return NULL; + return ERR_PTR(-ENODEV); /*XXX*/ } inet6_ifa_count++; @@ -551,6 +567,7 @@ in6_ifa_hold(ifa); write_unlock_bh(&idev->lock); read_unlock(&addrconf_lock); + spin_unlock_bh(&lock); notifier_call_chain(&inet6addr_chain,NETDEV_UP,ifa); @@ -697,7 +714,7 @@ ift = ipv6_count_addresses(idev) < IPV6_MAX_ADDRESSES ? ipv6_add_addr(idev, &addr, tmp_plen, ipv6_addr_type(&addr)&IPV6_ADDR_SCOPE_MASK, IFA_F_TEMPORARY) : 0; - if (!ift) { + if (IS_ERR(ift)) { in6_dev_put(idev); in6_ifa_put(ifp); printk(KERN_INFO @@ -928,6 +945,23 @@ return ifp != NULL; } +static +int ipv6_chk_same_addr(const struct in6_addr *addr, struct net_device *dev) +{ + struct inet6_ifaddr * ifp; + u8 hash = ipv6_addr_hash(addr); + + read_lock_bh(&addrconf_hash_lock); + for(ifp = inet6_addr_lst[hash]; ifp; ifp=ifp->lst_next) { + if (ipv6_addr_cmp(&ifp->addr, addr) == 0) { + if (dev == NULL || ifp->idev->dev == dev) + break; + } + } + read_unlock_bh(&addrconf_hash_lock); + return ifp != NULL; +} + struct inet6_ifaddr * ipv6_get_ifaddr(struct in6_addr *addr, struct net_device *dev) { struct inet6_ifaddr * ifp; @@ -1344,7 +1378,7 @@ ifp = ipv6_add_addr(in6_dev, &addr, pinfo->prefix_len, addr_type&IPV6_ADDR_SCOPE_MASK, 0); - if (ifp == NULL) { + if (IS_ERR(ifp)) { in6_dev_put(in6_dev); return; } @@ -1499,13 +1533,14 @@ scope = ipv6_addr_scope(pfx); - if ((ifp = ipv6_add_addr(idev, pfx, plen, scope, IFA_F_PERMANENT)) != NULL) { + ifp = ipv6_add_addr(idev, pfx, plen, scope, IFA_F_PERMANENT); + if (!IS_ERR(ifp)) { addrconf_dad_start(ifp); in6_ifa_put(ifp); return 0; } - return -ENOBUFS; + return PTR_ERR(ifp); } static int inet6_addr_del(int ifindex, struct in6_addr *pfx, int plen) @@ -1597,7 +1632,7 @@ if (addr.s6_addr32[3]) { ifp = ipv6_add_addr(idev, &addr, 128, scope, IFA_F_PERMANENT); - if (ifp) { + if (!IS_ERR(ifp)) { spin_lock_bh(&ifp->lock); ifp->flags &= ~IFA_F_TENTATIVE; spin_unlock_bh(&ifp->lock); @@ -1633,7 +1668,7 @@ ifp = ipv6_add_addr(idev, &addr, plen, flag, IFA_F_PERMANENT); - if (ifp) { + if (!IS_ERR(ifp)) { spin_lock_bh(&ifp->lock); ifp->flags &= ~IFA_F_TENTATIVE; spin_unlock_bh(&ifp->lock); @@ -1660,7 +1695,7 @@ } ifp = ipv6_add_addr(idev, &in6addr_loopback, 128, IFA_HOST, IFA_F_PERMANENT); - if (ifp) { + if (!IS_ERR(ifp)) { spin_lock_bh(&ifp->lock); ifp->flags &= ~IFA_F_TENTATIVE; spin_unlock_bh(&ifp->lock); @@ -1674,7 +1709,7 @@ struct inet6_ifaddr * ifp; ifp = ipv6_add_addr(idev, addr, 64, IFA_LINK, IFA_F_PERMANENT); - if (ifp) { + if (!IS_ERR(ifp)) { addrconf_dad_start(ifp); in6_ifa_put(ifp); } -- Hideaki YOSHIFUJI @ USAGI Project <yoshfuji@linux-ipv6.org> GPG FP: 9022 65EB 1ECF 3AD1 0BDF 80D8 4807 F894 E062 0EEA - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |