| Message ID | 20220315121026.778023-2-cascardo@canonical.com |
|---|---|
| State | New |
| Headers | show |
| Series | CVE-2022-0742 | expand |
On 15.03.22 13:10, Thadeu Lima de Souza Cascardo wrote: > From: Eric Dumazet <edumazet@google.com> > > While investigating on why a synchronize_net() has been added recently > in ipv6_mc_down(), I found that igmp6_event_query() and igmp6_event_report() > might drop skbs in some cases. > > Discussion about removing synchronize_net() from ipv6_mc_down() > will happen in a different thread. > > Fixes: f185de28d9ae ("mld: add new workqueues for process mld events") > Signed-off-by: Eric Dumazet <edumazet@google.com> > Cc: Taehee Yoo <ap420073@gmail.com> > Cc: Cong Wang <xiyou.wangcong@gmail.com> > Cc: David Ahern <dsahern@kernel.org> > Link: https://lore.kernel.org/r/20220303173728.937869-1-eric.dumazet@gmail.com > Signed-off-by: Jakub Kicinski <kuba@kernel.org> > (cherry picked from commit 2d3916f3189172d5c69d33065c3c21119fe539fc) > CVE-2022-0742 > Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> Acked-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com> Thanks > --- > include/net/ndisc.h | 4 ++-- > net/ipv6/mcast.c | 32 ++++++++++++-------------------- > 2 files changed, 14 insertions(+), 22 deletions(-) > > diff --git a/include/net/ndisc.h b/include/net/ndisc.h > index 38e4094960ce..e97ef508664f 100644 > --- a/include/net/ndisc.h > +++ b/include/net/ndisc.h > @@ -487,9 +487,9 @@ int igmp6_late_init(void); > void igmp6_cleanup(void); > void igmp6_late_cleanup(void); > > -int igmp6_event_query(struct sk_buff *skb); > +void igmp6_event_query(struct sk_buff *skb); > > -int igmp6_event_report(struct sk_buff *skb); > +void igmp6_event_report(struct sk_buff *skb); > > > #ifdef CONFIG_SYSCTL > diff --git a/net/ipv6/mcast.c b/net/ipv6/mcast.c > index d36ef9d25e73..e51b9c5d1ddf 100644 > --- a/net/ipv6/mcast.c > +++ b/net/ipv6/mcast.c > @@ -1366,27 +1366,23 @@ static int mld_process_v2(struct inet6_dev *idev, struct mld2_query *mld, > } > > /* called with rcu_read_lock() */ > -int igmp6_event_query(struct sk_buff *skb) > +void igmp6_event_query(struct sk_buff *skb) > { > struct inet6_dev *idev = __in6_dev_get(skb->dev); > > - if (!idev) > - return -EINVAL; > - > - if (idev->dead) { > - kfree_skb(skb); > - return -ENODEV; > - } > + if (!idev || idev->dead) > + goto out; > > spin_lock_bh(&idev->mc_query_lock); > if (skb_queue_len(&idev->mc_query_queue) < MLD_MAX_SKBS) { > __skb_queue_tail(&idev->mc_query_queue, skb); > if (!mod_delayed_work(mld_wq, &idev->mc_query_work, 0)) > in6_dev_hold(idev); > + skb = NULL; > } > spin_unlock_bh(&idev->mc_query_lock); > - > - return 0; > +out: > + kfree_skb(skb); > } > > static void __mld_query_work(struct sk_buff *skb) > @@ -1539,27 +1535,23 @@ static void mld_query_work(struct work_struct *work) > } > > /* called with rcu_read_lock() */ > -int igmp6_event_report(struct sk_buff *skb) > +void igmp6_event_report(struct sk_buff *skb) > { > struct inet6_dev *idev = __in6_dev_get(skb->dev); > > - if (!idev) > - return -EINVAL; > - > - if (idev->dead) { > - kfree_skb(skb); > - return -ENODEV; > - } > + if (!idev || idev->dead) > + goto out; > > spin_lock_bh(&idev->mc_report_lock); > if (skb_queue_len(&idev->mc_report_queue) < MLD_MAX_SKBS) { > __skb_queue_tail(&idev->mc_report_queue, skb); > if (!mod_delayed_work(mld_wq, &idev->mc_report_work, 0)) > in6_dev_hold(idev); > + skb = NULL; > } > spin_unlock_bh(&idev->mc_report_lock); > - > - return 0; > +out: > + kfree_skb(skb); > } > > static void __mld_report_work(struct sk_buff *skb)
diff --git a/include/net/ndisc.h b/include/net/ndisc.h index 38e4094960ce..e97ef508664f 100644 --- a/include/net/ndisc.h +++ b/include/net/ndisc.h @@ -487,9 +487,9 @@ int igmp6_late_init(void); void igmp6_cleanup(void); void igmp6_late_cleanup(void); -int igmp6_event_query(struct sk_buff *skb); +void igmp6_event_query(struct sk_buff *skb); -int igmp6_event_report(struct sk_buff *skb); +void igmp6_event_report(struct sk_buff *skb); #ifdef CONFIG_SYSCTL diff --git a/net/ipv6/mcast.c b/net/ipv6/mcast.c index d36ef9d25e73..e51b9c5d1ddf 100644 --- a/net/ipv6/mcast.c +++ b/net/ipv6/mcast.c @@ -1366,27 +1366,23 @@ static int mld_process_v2(struct inet6_dev *idev, struct mld2_query *mld, } /* called with rcu_read_lock() */ -int igmp6_event_query(struct sk_buff *skb) +void igmp6_event_query(struct sk_buff *skb) { struct inet6_dev *idev = __in6_dev_get(skb->dev); - if (!idev) - return -EINVAL; - - if (idev->dead) { - kfree_skb(skb); - return -ENODEV; - } + if (!idev || idev->dead) + goto out; spin_lock_bh(&idev->mc_query_lock); if (skb_queue_len(&idev->mc_query_queue) < MLD_MAX_SKBS) { __skb_queue_tail(&idev->mc_query_queue, skb); if (!mod_delayed_work(mld_wq, &idev->mc_query_work, 0)) in6_dev_hold(idev); + skb = NULL; } spin_unlock_bh(&idev->mc_query_lock); - - return 0; +out: + kfree_skb(skb); } static void __mld_query_work(struct sk_buff *skb) @@ -1539,27 +1535,23 @@ static void mld_query_work(struct work_struct *work) } /* called with rcu_read_lock() */ -int igmp6_event_report(struct sk_buff *skb) +void igmp6_event_report(struct sk_buff *skb) { struct inet6_dev *idev = __in6_dev_get(skb->dev); - if (!idev) - return -EINVAL; - - if (idev->dead) { - kfree_skb(skb); - return -ENODEV; - } + if (!idev || idev->dead) + goto out; spin_lock_bh(&idev->mc_report_lock); if (skb_queue_len(&idev->mc_report_queue) < MLD_MAX_SKBS) { __skb_queue_tail(&idev->mc_report_queue, skb); if (!mod_delayed_work(mld_wq, &idev->mc_report_work, 0)) in6_dev_hold(idev); + skb = NULL; } spin_unlock_bh(&idev->mc_report_lock); - - return 0; +out: + kfree_skb(skb); } static void __mld_report_work(struct sk_buff *skb)