inet: prevent leakage of uninitialized memory to user in recv syscalls
authorHannes Frederic Sowa <hannes@stressinduktion.org>
Mon, 18 Nov 2013 03:20:45 +0000 (04:20 +0100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sun, 8 Dec 2013 15:29:25 +0000 (07:29 -0800)
commita2214488937a84d8d0b5a3b546f97b2485029a17
tree533a832124d21321da8413805ee548886bcbf0b1
parentac6a5b926d2d8df1596f7cb91f46afc18e5e39f9
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>
net/ieee802154/dgram.c
net/ipv4/ping.c
net/ipv4/raw.c
net/ipv4/udp.c
net/ipv6/raw.c
net/ipv6/udp.c
net/l2tp/l2tp_ip.c
net/phonet/datagram.c