Skip to content

Commit

Permalink
[DECNET] address: Convert to new netlink interface
Browse files Browse the repository at this point in the history 
Extends the netlink interface to support the __le16 type and
converts address addition, deletion and, dumping to use the
new netlink interface.

Fixes multiple occasions of possible illegal memory references
due to not validated netlink attributes.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
  • Loading branch information
Thomas Graf authored and David S. Miller committed Dec 3, 2006
1 parent b020b94 commit 4a89c25
Show file tree
Hide file tree
Showing 2 changed files with 97 additions and 57 deletions.
12 changes: 12 additions & 0 deletions include/net/netlink.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -829,6 +829,9 @@ static inline int nla_put_msecs(struct sk_buff *skb, int attrtype,
#define NLA_PUT_U16(skb, attrtype, value) \
NLA_PUT_TYPE(skb, u16, attrtype, value)

#define NLA_PUT_LE16(skb, attrtype, value) \
NLA_PUT_TYPE(skb, __le16, attrtype, value)

#define NLA_PUT_U32(skb, attrtype, value) \
NLA_PUT_TYPE(skb, u32, attrtype, value)

Expand Down Expand Up @@ -874,6 +877,15 @@ static inline u16 nla_get_u16(struct nlattr *nla)
return *(u16 *) nla_data(nla);
}

/**
* nla_get_le16 - return payload of __le16 attribute
* @nla: __le16 netlink attribute
*/
static inline __le16 nla_get_le16(struct nlattr *nla)
{
return *(__le16 *) nla_data(nla);
}

/**
* nla_get_u8 - return payload of u8 attribute
* @nla: u8 netlink attribute
Expand Down
142 changes: 85 additions & 57 deletions net/decnet/dn_dev.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -645,41 +645,62 @@ static struct dn_dev *dn_dev_by_index(int ifindex)
return dn_dev;
}

static int dn_dev_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
static struct nla_policy dn_ifa_policy[IFA_MAX+1] __read_mostly = {
[IFA_ADDRESS] = { .type = NLA_U16 },
[IFA_LOCAL] = { .type = NLA_U16 },
[IFA_LABEL] = { .type = NLA_STRING,
.len = IFNAMSIZ - 1 },
};

static int dn_nl_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
{
struct rtattr **rta = arg;
struct nlattr *tb[IFA_MAX+1];
struct dn_dev *dn_db;
struct ifaddrmsg *ifm = NLMSG_DATA(nlh);
struct ifaddrmsg *ifm;
struct dn_ifaddr *ifa, **ifap;
int err = -EADDRNOTAVAIL;

err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, dn_ifa_policy);
if (err < 0)
goto errout;

ifm = nlmsg_data(nlh);
if ((dn_db = dn_dev_by_index(ifm->ifa_index)) == NULL)
return -EADDRNOTAVAIL;
goto errout;

for (ifap = &dn_db->ifa_list; (ifa = *ifap); ifap = &ifa->ifa_next) {
if (tb[IFA_LOCAL] &&
nla_memcmp(tb[IFA_LOCAL], &ifa->ifa_local, 2))
continue;

for(ifap = &dn_db->ifa_list; (ifa=*ifap) != NULL; ifap = &ifa->ifa_next) {
void *tmp = rta[IFA_LOCAL-1];
if ((tmp && memcmp(RTA_DATA(tmp), &ifa->ifa_local, 2)) ||
(rta[IFA_LABEL-1] && rtattr_strcmp(rta[IFA_LABEL-1], ifa->ifa_label)))
if (tb[IFA_LABEL] && nla_strcmp(tb[IFA_LABEL], ifa->ifa_label))
continue;

dn_dev_del_ifa(dn_db, ifap, 1);
return 0;
}

return -EADDRNOTAVAIL;
errout:
return err;
}

static int dn_dev_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
static int dn_nl_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
{
struct rtattr **rta = arg;
struct nlattr *tb[IFA_MAX+1];
struct net_device *dev;
struct dn_dev *dn_db;
struct ifaddrmsg *ifm = NLMSG_DATA(nlh);
struct ifaddrmsg *ifm;
struct dn_ifaddr *ifa;
int rv;
int err;

err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, dn_ifa_policy);
if (err < 0)
return err;

if (rta[IFA_LOCAL-1] == NULL)
if (tb[IFA_LOCAL] == NULL)
return -EINVAL;

ifm = nlmsg_data(nlh);
if ((dev = __dev_get_by_index(ifm->ifa_index)) == NULL)
return -ENODEV;

Expand All @@ -693,22 +714,25 @@ static int dn_dev_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh, void *a
if ((ifa = dn_dev_alloc_ifa()) == NULL)
return -ENOBUFS;

if (!rta[IFA_ADDRESS - 1])
rta[IFA_ADDRESS - 1] = rta[IFA_LOCAL - 1];
memcpy(&ifa->ifa_local, RTA_DATA(rta[IFA_LOCAL-1]), 2);
memcpy(&ifa->ifa_address, RTA_DATA(rta[IFA_ADDRESS-1]), 2);
if (tb[IFA_ADDRESS] == NULL)
tb[IFA_ADDRESS] = tb[IFA_LOCAL];

ifa->ifa_local = nla_get_le16(tb[IFA_LOCAL]);
ifa->ifa_address = nla_get_le16(tb[IFA_ADDRESS]);
ifa->ifa_flags = ifm->ifa_flags;
ifa->ifa_scope = ifm->ifa_scope;
ifa->ifa_dev = dn_db;
if (rta[IFA_LABEL-1])
rtattr_strlcpy(ifa->ifa_label, rta[IFA_LABEL-1], IFNAMSIZ);

if (tb[IFA_LABEL])
nla_strlcpy(ifa->ifa_label, tb[IFA_LABEL], IFNAMSIZ);
else
memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);

rv = dn_dev_insert_ifa(dn_db, ifa);
if (rv)
err = dn_dev_insert_ifa(dn_db, ifa);
if (err)
dn_dev_free_ifa(ifa);
return rv;

return err;
}

static inline size_t dn_ifaddr_nlmsg_size(void)
Expand All @@ -719,34 +743,34 @@ static inline size_t dn_ifaddr_nlmsg_size(void)
+ nla_total_size(2); /* IFA_LOCAL */
}

static int dn_dev_fill_ifaddr(struct sk_buff *skb, struct dn_ifaddr *ifa,
u32 pid, u32 seq, int event, unsigned int flags)
static int dn_nl_fill_ifaddr(struct sk_buff *skb, struct dn_ifaddr *ifa,
u32 pid, u32 seq, int event, unsigned int flags)
{
struct ifaddrmsg *ifm;
struct nlmsghdr *nlh;
unsigned char *b = skb->tail;

nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*ifm), flags);
ifm = NLMSG_DATA(nlh);
nlh = nlmsg_put(skb, pid, seq, event, sizeof(*ifm), flags);
if (nlh == NULL)
return -ENOBUFS;

ifm = nlmsg_data(nlh);
ifm->ifa_family = AF_DECnet;
ifm->ifa_prefixlen = 16;
ifm->ifa_flags = ifa->ifa_flags | IFA_F_PERMANENT;
ifm->ifa_scope = ifa->ifa_scope;
ifm->ifa_index = ifa->ifa_dev->dev->ifindex;

if (ifa->ifa_address)
RTA_PUT(skb, IFA_ADDRESS, 2, &ifa->ifa_address);
NLA_PUT_LE16(skb, IFA_ADDRESS, ifa->ifa_address);
if (ifa->ifa_local)
RTA_PUT(skb, IFA_LOCAL, 2, &ifa->ifa_local);
NLA_PUT_LE16(skb, IFA_LOCAL, ifa->ifa_local);
if (ifa->ifa_label[0])
RTA_PUT(skb, IFA_LABEL, IFNAMSIZ, &ifa->ifa_label);
nlh->nlmsg_len = skb->tail - b;
return skb->len;
NLA_PUT_STRING(skb, IFA_LABEL, ifa->ifa_label);

nlmsg_failure:
rtattr_failure:
skb_trim(skb, b - skb->data);
return -1;
return nlmsg_end(skb, nlh);

nla_put_failure:
return nlmsg_cancel(skb, nlh);
}

static void dn_ifaddr_notify(int event, struct dn_ifaddr *ifa)
Expand All @@ -758,7 +782,7 @@ static void dn_ifaddr_notify(int event, struct dn_ifaddr *ifa)
if (skb == NULL)
goto errout;

err = dn_dev_fill_ifaddr(skb, ifa, 0, 0, event, 0);
err = dn_nl_fill_ifaddr(skb, ifa, 0, 0, event, 0);
/* failure implies BUG in dn_ifaddr_nlmsg_size() */
BUG_ON(err < 0);

Expand All @@ -768,39 +792,43 @@ static void dn_ifaddr_notify(int event, struct dn_ifaddr *ifa)
rtnl_set_sk_err(RTNLGRP_DECnet_IFADDR, err);
}

static int dn_dev_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
static int dn_nl_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
{
int idx, dn_idx;
int s_idx, s_dn_idx;
int idx, dn_idx = 0, skip_ndevs, skip_naddr;
struct net_device *dev;
struct dn_dev *dn_db;
struct dn_ifaddr *ifa;

s_idx = cb->args[0];
s_dn_idx = dn_idx = cb->args[1];
skip_ndevs = cb->args[0];
skip_naddr = cb->args[1];

read_lock(&dev_base_lock);
for(dev = dev_base, idx = 0; dev; dev = dev->next, idx++) {
if (idx < s_idx)
for (dev = dev_base, idx = 0; dev; dev = dev->next, idx++) {
if (idx < skip_ndevs)
continue;
if (idx > s_idx)
s_dn_idx = 0;
else if (idx > skip_ndevs) {
/* Only skip over addresses for first dev dumped
* in this iteration (idx == skip_ndevs) */
skip_naddr = 0;
}

if ((dn_db = dev->dn_ptr) == NULL)
continue;

for(ifa = dn_db->ifa_list, dn_idx = 0; ifa; ifa = ifa->ifa_next, dn_idx++) {
if (dn_idx < s_dn_idx)
for (ifa = dn_db->ifa_list, dn_idx = 0; ifa;
ifa = ifa->ifa_next, dn_idx++) {
if (dn_idx < skip_naddr)
continue;

if (dn_dev_fill_ifaddr(skb, ifa,
NETLINK_CB(cb->skb).pid,
cb->nlh->nlmsg_seq,
RTM_NEWADDR,
NLM_F_MULTI) <= 0)
if (dn_nl_fill_ifaddr(skb, ifa, NETLINK_CB(cb->skb).pid,
cb->nlh->nlmsg_seq, RTM_NEWADDR,
NLM_F_MULTI) < 0)
goto done;
}
}
done:
read_unlock(&dev_base_lock);

cb->args[0] = idx;
cb->args[1] = dn_idx;

Expand Down Expand Up @@ -1417,9 +1445,9 @@ static struct file_operations dn_dev_seq_fops = {

static struct rtnetlink_link dnet_rtnetlink_table[RTM_NR_MSGTYPES] =
{
[RTM_NEWADDR - RTM_BASE] = { .doit = dn_dev_rtm_newaddr, },
[RTM_DELADDR - RTM_BASE] = { .doit = dn_dev_rtm_deladdr, },
[RTM_GETADDR - RTM_BASE] = { .dumpit = dn_dev_dump_ifaddr, },
[RTM_NEWADDR - RTM_BASE] = { .doit = dn_nl_newaddr, },
[RTM_DELADDR - RTM_BASE] = { .doit = dn_nl_deladdr, },
[RTM_GETADDR - RTM_BASE] = { .dumpit = dn_nl_dump_ifaddr, },
#ifdef CONFIG_DECNET_ROUTER
[RTM_NEWROUTE - RTM_BASE] = { .doit = dn_fib_rtm_newroute, },
[RTM_DELROUTE - RTM_BASE] = { .doit = dn_fib_rtm_delroute, },
Expand Down

0 comments on commit 4a89c25

Please sign in to comment.