4.4-stable review patch. If anyone has any objections, please let me know.
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From: Eric Dumazet edumazet@google.com
commit 30c7be26fd3587abcb69587f781098e3ca2d565b upstream.
In commits 93821778def10 ("udp: Fix rcv socket locking") and f7ad74fef3af ("net/ipv6/udp: UDP encapsulation: break backlog_rcv into __udpv6_queue_rcv_skb") UDP backlog handlers were renamed, but UDPlite was forgotten.
This leads to crashes if UDPlite header is pulled twice, which happens starting from commit e6afc8ace6dd ("udp: remove headers from UDP packets before queueing")
Bug found by syzkaller team, thanks a lot guys !
Note that backlog use in UDP/UDPlite is scheduled to be removed starting from linux-4.10, so this patch is only needed up to linux-4.9
Fixes: 93821778def1 ("udp: Fix rcv socket locking") Fixes: f7ad74fef3af ("net/ipv6/udp: UDP encapsulation: break backlog_rcv into __udpv6_queue_rcv_skb") Fixes: e6afc8ace6dd ("udp: remove headers from UDP packets before queueing") Signed-off-by: Eric Dumazet edumazet@google.com Reported-by: Andrey Konovalov andreyknvl@google.com Cc: Benjamin LaHaise bcrl@kvack.org Cc: Herbert Xu herbert@gondor.apana.org.au Signed-off-by: David S. Miller davem@davemloft.net Cc: Zubin Mithra zsm@chromium.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- net/ipv4/udp.c | 2 +- net/ipv4/udp_impl.h | 2 +- net/ipv4/udplite.c | 2 +- net/ipv6/udp.c | 2 +- net/ipv6/udp_impl.h | 2 +- net/ipv6/udplite.c | 2 +- 6 files changed, 6 insertions(+), 6 deletions(-)
--- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -1463,7 +1463,7 @@ static void udp_v4_rehash(struct sock *s udp_lib_rehash(sk, new_hash); }
-static int __udp_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) +int __udp_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) { int rc;
--- a/net/ipv4/udp_impl.h +++ b/net/ipv4/udp_impl.h @@ -25,7 +25,7 @@ int udp_recvmsg(struct sock *sk, struct int flags, int *addr_len); int udp_sendpage(struct sock *sk, struct page *page, int offset, size_t size, int flags); -int udp_queue_rcv_skb(struct sock *sk, struct sk_buff *skb); +int __udp_queue_rcv_skb(struct sock *sk, struct sk_buff *skb); void udp_destroy_sock(struct sock *sk);
#ifdef CONFIG_PROC_FS --- a/net/ipv4/udplite.c +++ b/net/ipv4/udplite.c @@ -50,7 +50,7 @@ struct proto udplite_prot = { .sendmsg = udp_sendmsg, .recvmsg = udp_recvmsg, .sendpage = udp_sendpage, - .backlog_rcv = udp_queue_rcv_skb, + .backlog_rcv = __udp_queue_rcv_skb, .hash = udp_lib_hash, .unhash = udp_lib_unhash, .get_port = udp_v4_get_port, --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -585,7 +585,7 @@ out: sock_put(sk); }
-static int __udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) +int __udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb) { int rc;
--- a/net/ipv6/udp_impl.h +++ b/net/ipv6/udp_impl.h @@ -26,7 +26,7 @@ int compat_udpv6_getsockopt(struct sock int udpv6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len); int udpv6_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int noblock, int flags, int *addr_len); -int udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb); +int __udpv6_queue_rcv_skb(struct sock *sk, struct sk_buff *skb); void udpv6_destroy_sock(struct sock *sk);
void udp_v6_clear_sk(struct sock *sk, int size); --- a/net/ipv6/udplite.c +++ b/net/ipv6/udplite.c @@ -45,7 +45,7 @@ struct proto udplitev6_prot = { .getsockopt = udpv6_getsockopt, .sendmsg = udpv6_sendmsg, .recvmsg = udpv6_recvmsg, - .backlog_rcv = udpv6_queue_rcv_skb, + .backlog_rcv = __udpv6_queue_rcv_skb, .hash = udp_lib_hash, .unhash = udp_lib_unhash, .get_port = udp_v6_get_port,