The irda_bind() function allocates memory for self->ias_obj without checking to see if the socket is already bound. A userspace process could repeatedly bind the socket, have each new object added into the LM-IAS database, and lose the reference to the old object assigned to the socket to exhaust memory resources. This patch errors out of the bind operation when self->ias_obj is already assigned.
CVE-2018-6554
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Tyler Hicks tyhicks@canonical.com Reviewed-by: Seth Arnold seth.arnold@canonical.com Reviewed-by: Stefan Bader stefan.bader@canonical.com --- drivers/staging/irda/net/af_irda.c | 7 +++++++ 1 file changed, 7 insertions(+)
diff --git a/drivers/staging/irda/net/af_irda.c b/drivers/staging/irda/net/af_irda.c index 23fa7c8b09a5..a08cd3dd7a6e 100644 --- a/drivers/staging/irda/net/af_irda.c +++ b/drivers/staging/irda/net/af_irda.c @@ -775,6 +775,13 @@ static int irda_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len) return -EINVAL;
lock_sock(sk); + + /* Ensure that the socket is not already bound */ + if (self->ias_obj) { + err = -EINVAL; + goto out; + } + #ifdef CONFIG_IRDA_ULTRA /* Special care for Ultra sockets */ if ((sk->sk_type == SOCK_DGRAM) &&