diff options
| author | Hannes Frederic Sowa <hannes@stressinduktion.org> | 2013-11-18 04:20:45 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-12-08 07:29:25 -0800 |
| commit | a2214488937a84d8d0b5a3b546f97b2485029a17 (patch) | |
| tree | 533a832124d21321da8413805ee548886bcbf0b1 /net/ipv6 | |
| parent | ac6a5b926d2d8df1596f7cb91f46afc18e5e39f9 (diff) | |
inet: prevent leakage of uninitialized memory to user in recv syscalls
[ Upstream commit bceaa90240b6019ed73b49965eac7d167610be69 ]
Only update *addr_len when we actually fill in sockaddr, otherwise we
can return uninitialized memory from the stack to the caller in the
recvfrom, recvmmsg and recvmsg syscalls. Drop the the (addr_len == NULL)
checks because we only get called with a valid addr_len pointer either
from sock_common_recvmsg or inet_recvmsg.
If a blocking read waits on a socket which is concurrently shut down we
now return zero and set msg_msgnamelen to 0.
Reported-by: mpb <mpb.mail@gmail.com>
Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'net/ipv6')
| -rw-r--r-- | net/ipv6/raw.c | 4 | ||||
| -rw-r--r-- | net/ipv6/udp.c | 5 |
2 files changed, 2 insertions, 7 deletions
diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c index eedff8ccded5..d3c01a601955 100644 --- a/net/ipv6/raw.c +++ b/net/ipv6/raw.c @@ -459,9 +459,6 @@ static int rawv6_recvmsg(struct kiocb *iocb, struct sock *sk, if (flags & MSG_OOB) return -EOPNOTSUPP; - if (addr_len) - *addr_len=sizeof(*sin6); - if (flags & MSG_ERRQUEUE) return ipv6_recv_error(sk, msg, len); @@ -500,6 +497,7 @@ static int rawv6_recvmsg(struct kiocb *iocb, struct sock *sk, sin6->sin6_flowinfo = 0; sin6->sin6_scope_id = ipv6_iface_scope_id(&sin6->sin6_addr, IP6CB(skb)->iif); + *addr_len = sizeof(*sin6); } sock_recv_ts_and_drops(msg, sk, skb); diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c index e7b28f9bb02b..f10f1186da0b 100644 --- a/net/ipv6/udp.c +++ b/net/ipv6/udp.c @@ -373,9 +373,6 @@ int udpv6_recvmsg(struct kiocb *iocb, struct sock *sk, int is_udp4; bool slow; - if (addr_len) - *addr_len = sizeof(struct sockaddr_in6); - if (flags & MSG_ERRQUEUE) return ipv6_recv_error(sk, msg, len); @@ -461,7 +458,7 @@ try_again: ipv6_iface_scope_id(&sin6->sin6_addr, IP6CB(skb)->iif); } - + *addr_len = sizeof(*sin6); } if (is_udp4) { if (inet->cmsg_flags) |