path: root/net/nfc
diff options
authorMathias Krause <minipli@googlemail.com>2013-04-07 01:51:58 +0000
committerDavid S. Miller <davem@davemloft.net>2013-04-07 16:28:02 -0400
commitd26d6504f23e803824e8ebd14e52d4fc0a0b09cb (patch)
treed0f8ff1e99ec304f1857b2efc397aa7c99cb11da /net/nfc
parent3ce5efad47b62c57a4f5c54248347085a750ce0e (diff)
NFC: llcp: fix info leaks via msg_name in llcp_sock_recvmsg()
The code in llcp_sock_recvmsg() does not initialize all the members of struct sockaddr_nfc_llcp when filling the sockaddr info. Nor does it initialize the padding bytes of the structure inserted by the compiler for alignment. Also, if the socket is in state LLCP_CLOSED or is shutting down during receive the msg_namelen member is not updated to 0 while otherwise returning with 0, i.e. "success". The msg_namelen update is also missing for stream and seqpacket sockets which don't fill the sockaddr info. Both issues lead to the fact that the code will leak uninitialized kernel stack bytes in net/socket.c. Fix the first issue by initializing the memory used for sockaddr info with memset(0). Fix the second one by setting msg_namelen to 0 early. It will be updated later if we're going to fill the msg_name member. Cc: Lauro Ramos Venancio <lauro.venancio@openbossa.org> Cc: Aloisio Almeida Jr <aloisio.almeida@openbossa.org> Cc: Samuel Ortiz <sameo@linux.intel.com> Signed-off-by: Mathias Krause <minipli@googlemail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/nfc')
1 files changed, 3 insertions, 0 deletions
diff --git a/net/nfc/llcp/sock.c b/net/nfc/llcp/sock.c
index 8f025746f337..6c94447ec414 100644
--- a/net/nfc/llcp/sock.c
+++ b/net/nfc/llcp/sock.c
@@ -646,6 +646,8 @@ static int llcp_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
pr_debug("%p %zu\n", sk, len);
+ msg->msg_namelen = 0;
if (sk->sk_state == LLCP_CLOSED &&
@@ -691,6 +693,7 @@ static int llcp_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
pr_debug("Datagram socket %d %d\n", ui_cb->dsap, ui_cb->ssap);
+ memset(sockaddr, 0, sizeof(*sockaddr));
sockaddr->sa_family = AF_NFC;
sockaddr->nfc_protocol = NFC_PROTO_NFC_DEP;
sockaddr->dsap = ui_cb->dsap;

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