For 4.19 kernel, this series includes backports of CVE-2022-3566 and CVE-2022-3567 fixes.
Eric Dumazet (1): ipv6: annotate some data-races around sk->sk_prot
Kuniyuki Iwashima (2): ipv6: Fix data races around sk->sk_prot. tcp: Fix data races around icsk->icsk_af_ops.
net/core/sock.c | 6 ++++-- net/ipv4/af_inet.c | 38 +++++++++++++++++++++++++++----------- net/ipv4/tcp.c | 10 ++++++---- net/ipv6/af_inet6.c | 14 ++++++++++---- net/ipv6/ipv6_sockglue.c | 9 ++++++--- net/ipv6/tcp_ipv6.c | 6 ++++-- 6 files changed, 57 insertions(+), 26 deletions(-)
From: Eric Dumazet edumazet@google.com
commit 086d49058cd8471046ae9927524708820f5fd1c7 upstream.
Changes from the original is that the applied code to inet6_sendmsg and inet6_recvmsg is ported to inet_sendmsg and inet_recvmsg because the same functions are shared between ipv4 and v6 in 4.19 kernel.
The original commit message is as below.
IPv6 has this hack changing sk->sk_prot when an IPv6 socket is 'converted' to an IPv4 one with IPV6_ADDRFORM option.
This operation is only performed for TCP and UDP, knowing their 'struct proto' for the two network families are populated in the same way, and can not disappear while a reader might use and dereference sk->sk_prot.
If we think about it all reads of sk->sk_prot while either socket lock or RTNL is not acquired should be using READ_ONCE().
Also note that other layers like MPTCP, XFRM, CHELSIO_TLS also write over sk->sk_prot.
BUG: KCSAN: data-race in inet6_recvmsg / ipv6_setsockopt
write to 0xffff8881386f7aa8 of 8 bytes by task 26932 on cpu 0: do_ipv6_setsockopt net/ipv6/ipv6_sockglue.c:492 [inline] ipv6_setsockopt+0x3758/0x3910 net/ipv6/ipv6_sockglue.c:1019 udpv6_setsockopt+0x85/0x90 net/ipv6/udp.c:1649 sock_common_setsockopt+0x5d/0x70 net/core/sock.c:3489 __sys_setsockopt+0x209/0x2a0 net/socket.c:2180 __do_sys_setsockopt net/socket.c:2191 [inline] __se_sys_setsockopt net/socket.c:2188 [inline] __x64_sys_setsockopt+0x62/0x70 net/socket.c:2188 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae
read to 0xffff8881386f7aa8 of 8 bytes by task 26911 on cpu 1: inet6_recvmsg+0x7a/0x210 net/ipv6/af_inet6.c:659 ____sys_recvmsg+0x16c/0x320 ___sys_recvmsg net/socket.c:2674 [inline] do_recvmmsg+0x3f5/0xae0 net/socket.c:2768 __sys_recvmmsg net/socket.c:2847 [inline] __do_sys_recvmmsg net/socket.c:2870 [inline] __se_sys_recvmmsg net/socket.c:2863 [inline] __x64_sys_recvmmsg+0xde/0x160 net/socket.c:2863 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae
value changed: 0xffffffff85e0e980 -> 0xffffffff85e01580
Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 26911 Comm: syz-executor.3 Not tainted 5.17.0-rc2-syzkaller-00316-g0457e5153e0e-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Reported-by: syzbot syzkaller@googlegroups.com Signed-off-by: Eric Dumazet edumazet@google.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Kazunori Kobayashi kazunori.kobayashi@miraclelinux.com --- net/ipv4/af_inet.c | 15 +++++++++++---- net/ipv6/af_inet6.c | 14 ++++++++++---- net/ipv6/ipv6_sockglue.c | 6 ++++-- 3 files changed, 25 insertions(+), 10 deletions(-)
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index 01952a520d6fe..3c9e05332f179 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -789,15 +789,19 @@ EXPORT_SYMBOL(inet_getname); int inet_sendmsg(struct socket *sock, struct msghdr *msg, size_t size) { struct sock *sk = sock->sk; + const struct proto *prot;
sock_rps_record_flow(sk);
+ /* IPV6_ADDRFORM can change sk->sk_prot under us. */ + prot = READ_ONCE(sk->sk_prot); + /* We may need to bind the socket. */ - if (!inet_sk(sk)->inet_num && !sk->sk_prot->no_autobind && + if (!inet_sk(sk)->inet_num && !prot->no_autobind && inet_autobind(sk)) return -EAGAIN;
- return sk->sk_prot->sendmsg(sk, msg, size); + return prot->sendmsg(sk, msg, size); } EXPORT_SYMBOL(inet_sendmsg);
@@ -823,14 +827,17 @@ int inet_recvmsg(struct socket *sock, struct msghdr *msg, size_t size, int flags) { struct sock *sk = sock->sk; + const struct proto *prot; int addr_len = 0; int err;
if (likely(!(flags & MSG_ERRQUEUE))) sock_rps_record_flow(sk);
- err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT, - flags & ~MSG_DONTWAIT, &addr_len); + /* IPV6_ADDRFORM can change sk->sk_prot under us. */ + prot = READ_ONCE(sk->sk_prot); + err = prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT, + flags & ~MSG_DONTWAIT, &addr_len); if (err >= 0) msg->msg_namelen = addr_len; return err; diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c index c8f39d61b51e1..f480436b84339 100644 --- a/net/ipv6/af_inet6.c +++ b/net/ipv6/af_inet6.c @@ -443,11 +443,14 @@ static int __inet6_bind(struct sock *sk, struct sockaddr *uaddr, int addr_len, int inet6_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len) { struct sock *sk = sock->sk; + const struct proto *prot; int err = 0;
+ /* IPV6_ADDRFORM can change sk->sk_prot under us. */ + prot = READ_ONCE(sk->sk_prot); /* If the socket has its own bind function then use it. */ - if (sk->sk_prot->bind) - return sk->sk_prot->bind(sk, uaddr, addr_len); + if (prot->bind) + return prot->bind(sk, uaddr, addr_len);
if (addr_len < SIN6_LEN_RFC2133) return -EINVAL; @@ -558,6 +561,7 @@ int inet6_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) { struct sock *sk = sock->sk; struct net *net = sock_net(sk); + const struct proto *prot;
switch (cmd) { case SIOCGSTAMP: @@ -578,9 +582,11 @@ int inet6_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg) case SIOCSIFDSTADDR: return addrconf_set_dstaddr(net, (void __user *) arg); default: - if (!sk->sk_prot->ioctl) + /* IPV6_ADDRFORM can change sk->sk_prot under us. */ + prot = READ_ONCE(sk->sk_prot); + if (!prot->ioctl) return -ENOIOCTLCMD; - return sk->sk_prot->ioctl(sk, cmd, arg); + return prot->ioctl(sk, cmd, arg); } /*NOTREACHED*/ return 0; diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c index 1c155e610c06d..91facff119357 100644 --- a/net/ipv6/ipv6_sockglue.c +++ b/net/ipv6/ipv6_sockglue.c @@ -224,7 +224,8 @@ static int do_ipv6_setsockopt(struct sock *sk, int level, int optname, sock_prot_inuse_add(net, sk->sk_prot, -1); sock_prot_inuse_add(net, &tcp_prot, 1); local_bh_enable(); - sk->sk_prot = &tcp_prot; + /* Paired with READ_ONCE(sk->sk_prot) in net/ipv6/af_inet6.c */ + WRITE_ONCE(sk->sk_prot, &tcp_prot); icsk->icsk_af_ops = &ipv4_specific; sk->sk_socket->ops = &inet_stream_ops; sk->sk_family = PF_INET; @@ -238,7 +239,8 @@ static int do_ipv6_setsockopt(struct sock *sk, int level, int optname, sock_prot_inuse_add(net, sk->sk_prot, -1); sock_prot_inuse_add(net, prot, 1); local_bh_enable(); - sk->sk_prot = prot; + /* Paired with READ_ONCE(sk->sk_prot) in net/ipv6/af_inet6.c */ + WRITE_ONCE(sk->sk_prot, prot); sk->sk_socket->ops = &inet_dgram_ops; sk->sk_family = PF_INET; }
From: Kuniyuki Iwashima kuniyu@amazon.com
commit 364f997b5cfe1db0d63a390fe7c801fa2b3115f6 upstream.
Commit 086d49058cd8 ("ipv6: annotate some data-races around sk->sk_prot") fixed some data-races around sk->sk_prot but it was not enough.
Some functions in inet6_(stream|dgram)_ops still access sk->sk_prot without lock_sock() or rtnl_lock(), so they need READ_ONCE() to avoid load tearing.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kuniyuki Iwashima kuniyu@amazon.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Kazunori Kobayashi kazunori.kobayashi@miraclelinux.com --- net/core/sock.c | 6 ++++-- net/ipv4/af_inet.c | 23 ++++++++++++++++------- net/ipv6/ipv6_sockglue.c | 4 ++-- 3 files changed, 22 insertions(+), 11 deletions(-)
diff --git a/net/core/sock.c b/net/core/sock.c index c1d60df487fc0..fd467b96fceac 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -3064,7 +3064,8 @@ int sock_common_getsockopt(struct socket *sock, int level, int optname, { struct sock *sk = sock->sk;
- return sk->sk_prot->getsockopt(sk, level, optname, optval, optlen); + /* IPV6_ADDRFORM can change sk->sk_prot under us. */ + return READ_ONCE(sk->sk_prot)->getsockopt(sk, level, optname, optval, optlen); } EXPORT_SYMBOL(sock_common_getsockopt);
@@ -3105,7 +3106,8 @@ int sock_common_setsockopt(struct socket *sock, int level, int optname, { struct sock *sk = sock->sk;
- return sk->sk_prot->setsockopt(sk, level, optname, optval, optlen); + /* IPV6_ADDRFORM can change sk->sk_prot under us. */ + return READ_ONCE(sk->sk_prot)->setsockopt(sk, level, optname, optval, optlen); } EXPORT_SYMBOL(sock_common_setsockopt);
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index 3c9e05332f179..8ec107748159b 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -553,22 +553,27 @@ int inet_dgram_connect(struct socket *sock, struct sockaddr *uaddr, int addr_len, int flags) { struct sock *sk = sock->sk; + const struct proto *prot; int err;
if (addr_len < sizeof(uaddr->sa_family)) return -EINVAL; + + /* IPV6_ADDRFORM can change sk->sk_prot under us. */ + prot = READ_ONCE(sk->sk_prot); + if (uaddr->sa_family == AF_UNSPEC) - return sk->sk_prot->disconnect(sk, flags); + return prot->disconnect(sk, flags);
if (BPF_CGROUP_PRE_CONNECT_ENABLED(sk)) { - err = sk->sk_prot->pre_connect(sk, uaddr, addr_len); + err = prot->pre_connect(sk, uaddr, addr_len); if (err) return err; }
if (!inet_sk(sk)->inet_num && inet_autobind(sk)) return -EAGAIN; - return sk->sk_prot->connect(sk, uaddr, addr_len); + return prot->connect(sk, uaddr, addr_len); } EXPORT_SYMBOL(inet_dgram_connect);
@@ -731,10 +736,11 @@ EXPORT_SYMBOL(inet_stream_connect); int inet_accept(struct socket *sock, struct socket *newsock, int flags, bool kern) { - struct sock *sk1 = sock->sk; + struct sock *sk1 = sock->sk, *sk2; int err = -EINVAL; - struct sock *sk2 = sk1->sk_prot->accept(sk1, flags, &err, kern);
+ /* IPV6_ADDRFORM can change sk->sk_prot under us. */ + sk2 = READ_ONCE(sk1->sk_prot)->accept(sk1, flags, &err, kern); if (!sk2) goto do_err;
@@ -809,6 +815,7 @@ ssize_t inet_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags) { struct sock *sk = sock->sk; + const struct proto *prot;
sock_rps_record_flow(sk);
@@ -817,8 +824,10 @@ ssize_t inet_sendpage(struct socket *sock, struct page *page, int offset, inet_autobind(sk)) return -EAGAIN;
- if (sk->sk_prot->sendpage) - return sk->sk_prot->sendpage(sk, page, offset, size, flags); + /* IPV6_ADDRFORM can change sk->sk_prot under us. */ + prot = READ_ONCE(sk->sk_prot); + if (prot->sendpage) + return prot->sendpage(sk, page, offset, size, flags); return sock_no_sendpage(sock, page, offset, size, flags); } EXPORT_SYMBOL(inet_sendpage); diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c index 91facff119357..625cece87c122 100644 --- a/net/ipv6/ipv6_sockglue.c +++ b/net/ipv6/ipv6_sockglue.c @@ -224,7 +224,7 @@ static int do_ipv6_setsockopt(struct sock *sk, int level, int optname, sock_prot_inuse_add(net, sk->sk_prot, -1); sock_prot_inuse_add(net, &tcp_prot, 1); local_bh_enable(); - /* Paired with READ_ONCE(sk->sk_prot) in net/ipv6/af_inet6.c */ + /* Paired with READ_ONCE(sk->sk_prot) in inet6_stream_ops */ WRITE_ONCE(sk->sk_prot, &tcp_prot); icsk->icsk_af_ops = &ipv4_specific; sk->sk_socket->ops = &inet_stream_ops; @@ -239,7 +239,7 @@ static int do_ipv6_setsockopt(struct sock *sk, int level, int optname, sock_prot_inuse_add(net, sk->sk_prot, -1); sock_prot_inuse_add(net, prot, 1); local_bh_enable(); - /* Paired with READ_ONCE(sk->sk_prot) in net/ipv6/af_inet6.c */ + /* Paired with READ_ONCE(sk->sk_prot) in inet6_dgram_ops */ WRITE_ONCE(sk->sk_prot, prot); sk->sk_socket->ops = &inet_dgram_ops; sk->sk_family = PF_INET;
From: Kuniyuki Iwashima kuniyu@amazon.com
commit f49cd2f4d6170d27a2c61f1fecb03d8a70c91f57 upstream.
setsockopt(IPV6_ADDRFORM) and tcp_v6_connect() change icsk->icsk_af_ops under lock_sock(), but tcp_(get|set)sockopt() read it locklessly. To avoid load/store tearing, we need to add READ_ONCE() and WRITE_ONCE() for the reads and writes.
Thanks to Eric Dumazet for providing the syzbot report:
BUG: KCSAN: data-race in tcp_setsockopt / tcp_v6_connect
write to 0xffff88813c624518 of 8 bytes by task 23936 on cpu 0: tcp_v6_connect+0x5b3/0xce0 net/ipv6/tcp_ipv6.c:240 __inet_stream_connect+0x159/0x6d0 net/ipv4/af_inet.c:660 inet_stream_connect+0x44/0x70 net/ipv4/af_inet.c:724 __sys_connect_file net/socket.c:1976 [inline] __sys_connect+0x197/0x1b0 net/socket.c:1993 __do_sys_connect net/socket.c:2003 [inline] __se_sys_connect net/socket.c:2000 [inline] __x64_sys_connect+0x3d/0x50 net/socket.c:2000 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd
read to 0xffff88813c624518 of 8 bytes by task 23937 on cpu 1: tcp_setsockopt+0x147/0x1c80 net/ipv4/tcp.c:3789 sock_common_setsockopt+0x5d/0x70 net/core/sock.c:3585 __sys_setsockopt+0x212/0x2b0 net/socket.c:2252 __do_sys_setsockopt net/socket.c:2263 [inline] __se_sys_setsockopt net/socket.c:2260 [inline] __x64_sys_setsockopt+0x62/0x70 net/socket.c:2260 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd
value changed: 0xffffffff8539af68 -> 0xffffffff8539aff8
Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 23937 Comm: syz-executor.5 Not tainted 6.0.0-rc4-syzkaller-00331-g4ed9c1e971b1-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzbot syzkaller@googlegroups.com Reported-by: Eric Dumazet edumazet@google.com Signed-off-by: Kuniyuki Iwashima kuniyu@amazon.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Kazunori Kobayashi kazunori.kobayashi@miraclelinux.com --- net/ipv4/tcp.c | 10 ++++++---- net/ipv6/ipv6_sockglue.c | 3 ++- net/ipv6/tcp_ipv6.c | 6 ++++-- 3 files changed, 12 insertions(+), 7 deletions(-)
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index e3475f833f8fe..c863be23ac4db 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -3126,8 +3126,9 @@ int tcp_setsockopt(struct sock *sk, int level, int optname, char __user *optval, const struct inet_connection_sock *icsk = inet_csk(sk);
if (level != SOL_TCP) - return icsk->icsk_af_ops->setsockopt(sk, level, optname, - optval, optlen); + /* Paired with WRITE_ONCE() in do_ipv6_setsockopt() and tcp_v6_connect() */ + return READ_ONCE(icsk->icsk_af_ops)->setsockopt(sk, level, optname, + optval, optlen); return do_tcp_setsockopt(sk, level, optname, optval, optlen); } EXPORT_SYMBOL(tcp_setsockopt); @@ -3649,8 +3650,9 @@ int tcp_getsockopt(struct sock *sk, int level, int optname, char __user *optval, struct inet_connection_sock *icsk = inet_csk(sk);
if (level != SOL_TCP) - return icsk->icsk_af_ops->getsockopt(sk, level, optname, - optval, optlen); + /* Paired with WRITE_ONCE() in do_ipv6_setsockopt() and tcp_v6_connect() */ + return READ_ONCE(icsk->icsk_af_ops)->getsockopt(sk, level, optname, + optval, optlen); return do_tcp_getsockopt(sk, level, optname, optval, optlen); } EXPORT_SYMBOL(tcp_getsockopt); diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c index 625cece87c122..caa7b59c819ee 100644 --- a/net/ipv6/ipv6_sockglue.c +++ b/net/ipv6/ipv6_sockglue.c @@ -226,7 +226,8 @@ static int do_ipv6_setsockopt(struct sock *sk, int level, int optname, local_bh_enable(); /* Paired with READ_ONCE(sk->sk_prot) in inet6_stream_ops */ WRITE_ONCE(sk->sk_prot, &tcp_prot); - icsk->icsk_af_ops = &ipv4_specific; + /* Paired with READ_ONCE() in tcp_(get|set)sockopt() */ + WRITE_ONCE(icsk->icsk_af_ops, &ipv4_specific); sk->sk_socket->ops = &inet_stream_ops; sk->sk_family = PF_INET; tcp_sync_mss(sk, icsk->icsk_pmtu_cookie); diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index 033cf81f34837..78eaaf59c15e2 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -229,7 +229,8 @@ static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr, sin.sin_port = usin->sin6_port; sin.sin_addr.s_addr = usin->sin6_addr.s6_addr32[3];
- icsk->icsk_af_ops = &ipv6_mapped; + /* Paired with READ_ONCE() in tcp_(get|set)sockopt() */ + WRITE_ONCE(icsk->icsk_af_ops, &ipv6_mapped); sk->sk_backlog_rcv = tcp_v4_do_rcv; #ifdef CONFIG_TCP_MD5SIG tp->af_specific = &tcp_sock_ipv6_mapped_specific; @@ -239,7 +240,8 @@ static int tcp_v6_connect(struct sock *sk, struct sockaddr *uaddr,
if (err) { icsk->icsk_ext_hdr_len = exthdrlen; - icsk->icsk_af_ops = &ipv6_specific; + /* Paired with READ_ONCE() in tcp_(get|set)sockopt() */ + WRITE_ONCE(icsk->icsk_af_ops, &ipv6_specific); sk->sk_backlog_rcv = tcp_v6_do_rcv; #ifdef CONFIG_TCP_MD5SIG tp->af_specific = &tcp_sock_ipv6_specific;
linux-stable-mirror@lists.linaro.org
-
Kazunori Kobayashi