| Message ID | 20160323173818.GA11724@salvia |
|---|---|
| State | RFC, archived |
| Delegated to: | David Miller |
| Headers | show |
2016-03-24 1:38 GMT+08:00, Pablo Neira Ayuso <pablo@netfilter.org>: > On Thu, Mar 24, 2016 at 12:42:43AM +0800, Baozeng wrote: >> 2016-03-22 23:27 GMT+08:00 Eric Dumazet <eric.dumazet@gmail.com>: >> > Untested patch would be : >> > >> > diff --git a/net/bridge/netfilter/ebtables.c >> > b/net/bridge/netfilter/ebtables.c >> > index 67b2e27999aa..fceb7354d169 100644 >> > --- a/net/bridge/netfilter/ebtables.c >> > +++ b/net/bridge/netfilter/ebtables.c >> > @@ -346,7 +346,7 @@ find_inlist_lock(struct list_head *head, const char >> > *name, const char *prefix, >> > { >> > return try_then_request_module( >> > find_inlist_lock_noload(head, name, error, >> > mutex), >> > - "%s%s", prefix, name); >> > + "%.*s%s", EBT_TABLE_MAXNAMELEN, prefix, name); >> > } >> > >> > static inline struct ebt_table * >> > >> > >> >> Thanks for your quick patch. I tested it but it still reproduce the >> bug. We should limit the length of the name, >> not the prefix. The following patch fixs it. > > Could you give a try to this patch? Thanks. > I tested with your patch. It fixs the bug. Thanks.
diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c index 67b2e27..1e3a707 100644 --- a/net/bridge/netfilter/ebtables.c +++ b/net/bridge/netfilter/ebtables.c @@ -1521,6 +1521,8 @@ static int do_ebt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len) if (copy_from_user(&tmp, user, sizeof(tmp))) return -EFAULT; + tmp.name[sizeof(tmp.name) - 1] = '\0'; + t = find_table_lock(net, tmp.name, &ret, &ebt_mutex); if (!t) return ret; diff --git a/net/ipv4/netfilter/arp_tables.c b/net/ipv4/netfilter/arp_tables.c index a2002ff..06e9fb7 100644 --- a/net/ipv4/netfilter/arp_tables.c +++ b/net/ipv4/netfilter/arp_tables.c @@ -960,6 +960,7 @@ static int get_entries(struct net *net, struct arpt_get_entries __user *uptr, sizeof(struct arpt_get_entries) + get.size); return -EINVAL; } + get.name[sizeof(get.name) - 1] = '\0'; t = xt_find_table_lock(net, NFPROTO_ARP, get.name); if (!IS_ERR_OR_NULL(t)) { @@ -1654,6 +1655,7 @@ static int compat_get_entries(struct net *net, *len, sizeof(get) + get.size); return -EINVAL; } + get.name[sizeof(get.name) - 1] = '\0'; xt_compat_lock(NFPROTO_ARP); t = xt_find_table_lock(net, NFPROTO_ARP, get.name); diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c index 45b1d97..4642dc2 100644 --- a/net/ipv4/netfilter/ip_tables.c +++ b/net/ipv4/netfilter/ip_tables.c @@ -1146,6 +1146,7 @@ get_entries(struct net *net, struct ipt_get_entries __user *uptr, *len, sizeof(get) + get.size); return -EINVAL; } + get.name[sizeof(get.name) - 1] = '\0'; t = xt_find_table_lock(net, AF_INET, get.name); if (!IS_ERR_OR_NULL(t)) { @@ -1925,6 +1926,7 @@ compat_get_entries(struct net *net, struct compat_ipt_get_entries __user *uptr, *len, sizeof(get) + get.size); return -EINVAL; } + get.name[sizeof(get.name) - 1] = '\0'; xt_compat_lock(AF_INET); t = xt_find_table_lock(net, AF_INET, get.name); diff --git a/net/ipv6/netfilter/ip6_tables.c b/net/ipv6/netfilter/ip6_tables.c index 85c0942..db47815 100644 --- a/net/ipv6/netfilter/ip6_tables.c +++ b/net/ipv6/netfilter/ip6_tables.c @@ -1158,6 +1158,7 @@ get_entries(struct net *net, struct ip6t_get_entries __user *uptr, *len, sizeof(get) + get.size); return -EINVAL; } + get.name[sizeof(get.name) - 1] = '\0'; t = xt_find_table_lock(net, AF_INET6, get.name); if (!IS_ERR_OR_NULL(t)) { @@ -1934,6 +1935,7 @@ compat_get_entries(struct net *net, struct compat_ip6t_get_entries __user *uptr, *len, sizeof(get) + get.size); return -EINVAL; } + get.name[sizeof(get.name) - 1] = '\0'; xt_compat_lock(AF_INET6); t = xt_find_table_lock(net, AF_INET6, get.name);