| Message ID | 20181226035002.73614-1-kjlu@umn.edu |
|---|---|
| State | Changes Requested |
| Delegated to: | Jozsef Kadlecsik |
| Headers | show |
| Series | ipset: fix a missing check of nla_parse | expand |
On 26.12.2018 06:50, Kangjie Lu wrote: > When nla_parse fails, we should not use the results (the first > argument). The fix checks if it fails, and if so, returns its error code > upstream. > > Signed-off-by: Kangjie Lu <kjlu@umn.edu> > --- > net/netfilter/ipset/ip_set_core.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/net/netfilter/ipset/ip_set_core.c b/net/netfilter/ipset/ip_set_core.c > index 1577f2f76060..4dc8057cff02 100644 > --- a/net/netfilter/ipset/ip_set_core.c > +++ b/net/netfilter/ipset/ip_set_core.c > @@ -1531,8 +1531,10 @@ call_ad(struct sock *ctnl, struct sk_buff *skb, struct ip_set *set, > memcpy(&errmsg->msg, nlh, nlh->nlmsg_len); > cmdattr = (void *)&errmsg->msg + min_len; > > - nla_parse(cda, IPSET_ATTR_CMD_MAX, cmdattr, > + ret = nla_parse(cda, IPSET_ATTR_CMD_MAX, cmdattr, > nlh->nlmsg_len - min_len, ip_set_adt_policy, NULL); > + if (ret) > + return ret; In this function above nlmsg_new() allocates skb2, but I don't see, where you free it here. > > errline = nla_data(cda[IPSET_ATTR_LINENO]); > >
On Wed, Dec 26, 2018 at 12:16:25PM +0300, Kirill Tkhai wrote: > On 26.12.2018 06:50, Kangjie Lu wrote: > > When nla_parse fails, we should not use the results (the first > > argument). The fix checks if it fails, and if so, returns its error code > > upstream. > > > > Signed-off-by: Kangjie Lu <kjlu@umn.edu> > > --- > > net/netfilter/ipset/ip_set_core.c | 4 +++- > > 1 file changed, 3 insertions(+), 1 deletion(-) > > > > diff --git a/net/netfilter/ipset/ip_set_core.c b/net/netfilter/ipset/ip_set_core.c > > index 1577f2f76060..4dc8057cff02 100644 > > --- a/net/netfilter/ipset/ip_set_core.c > > +++ b/net/netfilter/ipset/ip_set_core.c > > @@ -1531,8 +1531,10 @@ call_ad(struct sock *ctnl, struct sk_buff *skb, struct ip_set *set, > > memcpy(&errmsg->msg, nlh, nlh->nlmsg_len); > > cmdattr = (void *)&errmsg->msg + min_len; > > > > - nla_parse(cda, IPSET_ATTR_CMD_MAX, cmdattr, > > + ret = nla_parse(cda, IPSET_ATTR_CMD_MAX, cmdattr, > > nlh->nlmsg_len - min_len, ip_set_adt_policy, NULL); @Kangjie: nitpick, could you align this line below? ie. ret = nla_parse(cda, IPSET_ATTR_CMD_MAX, cmdattr, nlh->nlmsg_len - min_len, ip_set_adt_policy, NULL); > > + if (ret) > > + return ret; > > In this function above nlmsg_new() allocates skb2, but I don't see, where you free it here. netlink_unicast() is responsible for releasing this skb2. > > errline = nla_data(cda[IPSET_ATTR_LINENO]); > > > >
On 10.01.2019 01:43, Pablo Neira Ayuso wrote: > On Wed, Dec 26, 2018 at 12:16:25PM +0300, Kirill Tkhai wrote: >> On 26.12.2018 06:50, Kangjie Lu wrote: >>> When nla_parse fails, we should not use the results (the first >>> argument). The fix checks if it fails, and if so, returns its error code >>> upstream. >>> >>> Signed-off-by: Kangjie Lu <kjlu@umn.edu> >>> --- >>> net/netfilter/ipset/ip_set_core.c | 4 +++- >>> 1 file changed, 3 insertions(+), 1 deletion(-) >>> >>> diff --git a/net/netfilter/ipset/ip_set_core.c b/net/netfilter/ipset/ip_set_core.c >>> index 1577f2f76060..4dc8057cff02 100644 >>> --- a/net/netfilter/ipset/ip_set_core.c >>> +++ b/net/netfilter/ipset/ip_set_core.c >>> @@ -1531,8 +1531,10 @@ call_ad(struct sock *ctnl, struct sk_buff *skb, struct ip_set *set, >>> memcpy(&errmsg->msg, nlh, nlh->nlmsg_len); >>> cmdattr = (void *)&errmsg->msg + min_len; >>> >>> - nla_parse(cda, IPSET_ATTR_CMD_MAX, cmdattr, >>> + ret = nla_parse(cda, IPSET_ATTR_CMD_MAX, cmdattr, >>> nlh->nlmsg_len - min_len, ip_set_adt_policy, NULL); > > @Kangjie: nitpick, could you align this line below? ie. > > ret = nla_parse(cda, IPSET_ATTR_CMD_MAX, cmdattr, > nlh->nlmsg_len - min_len, ip_set_adt_policy, > NULL); > >>> + if (ret) >>> + return ret; >> >> In this function above nlmsg_new() allocates skb2, but I don't see, where you free it here. > > netlink_unicast() is responsible for releasing this skb2. We return earlier at "if (ret)", so netlink_unicast() is not called. >>> errline = nla_data(cda[IPSET_ATTR_LINENO]); Kirill
diff --git a/net/netfilter/ipset/ip_set_core.c b/net/netfilter/ipset/ip_set_core.c index 1577f2f76060..4dc8057cff02 100644 --- a/net/netfilter/ipset/ip_set_core.c +++ b/net/netfilter/ipset/ip_set_core.c @@ -1531,8 +1531,10 @@ call_ad(struct sock *ctnl, struct sk_buff *skb, struct ip_set *set, memcpy(&errmsg->msg, nlh, nlh->nlmsg_len); cmdattr = (void *)&errmsg->msg + min_len; - nla_parse(cda, IPSET_ATTR_CMD_MAX, cmdattr, + ret = nla_parse(cda, IPSET_ATTR_CMD_MAX, cmdattr, nlh->nlmsg_len - min_len, ip_set_adt_policy, NULL); + if (ret) + return ret; errline = nla_data(cda[IPSET_ATTR_LINENO]);
When nla_parse fails, we should not use the results (the first argument). The fix checks if it fails, and if so, returns its error code upstream. Signed-off-by: Kangjie Lu <kjlu@umn.edu> --- net/netfilter/ipset/ip_set_core.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)