From: Bernard Metzler bmt@zurich.ibm.com
commit 33fb27fd54465c74cbffba6315b2f043e90cec4c upstream.
Holding the rtnl_lock while iterating a devices interface address list potentially causes deadlocks with the cma_netdev_callback. While this was implemented to limit the scope of a wildcard listen to addresses of the current device only, a better solution limits the scope of the socket to the device. This completely avoiding locking, and also results in significant code simplification.
Fixes: c421651fa229 ("RDMA/siw: Add missing rtnl_lock around access to ifa") Link: https://lore.kernel.org/r/20200228173534.26815-1-bmt@zurich.ibm.com Reported-by: syzbot+55de90ab5f44172b0c90@syzkaller.appspotmail.com Suggested-by: Jason Gunthorpe jgg@ziepe.ca Signed-off-by: Bernard Metzler bmt@zurich.ibm.com Signed-off-by: Jason Gunthorpe jgg@mellanox.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/infiniband/sw/siw/siw_cm.c | 137 ++++++++----------------------------- 1 file changed, 31 insertions(+), 106 deletions(-)
--- a/drivers/infiniband/sw/siw/siw_cm.c +++ b/drivers/infiniband/sw/siw/siw_cm.c @@ -1769,14 +1769,23 @@ int siw_reject(struct iw_cm_id *id, cons return 0; }
-static int siw_listen_address(struct iw_cm_id *id, int backlog, - struct sockaddr *laddr, int addr_family) +/* + * siw_create_listen - Create resources for a listener's IWCM ID @id + * + * Starts listen on the socket address id->local_addr. + * + */ +int siw_create_listen(struct iw_cm_id *id, int backlog) { struct socket *s; struct siw_cep *cep = NULL; struct siw_device *sdev = to_siw_dev(id->device); + int addr_family = id->local_addr.ss_family; int rv = 0, s_val;
+ if (addr_family != AF_INET && addr_family != AF_INET6) + return -EAFNOSUPPORT; + rv = sock_create(addr_family, SOCK_STREAM, IPPROTO_TCP, &s); if (rv < 0) return rv; @@ -1791,9 +1800,25 @@ static int siw_listen_address(struct iw_ siw_dbg(id->device, "setsockopt error: %d\n", rv); goto error; } - rv = s->ops->bind(s, laddr, addr_family == AF_INET ? - sizeof(struct sockaddr_in) : - sizeof(struct sockaddr_in6)); + if (addr_family == AF_INET) { + struct sockaddr_in *laddr = &to_sockaddr_in(id->local_addr); + + /* For wildcard addr, limit binding to current device only */ + if (ipv4_is_zeronet(laddr->sin_addr.s_addr)) + s->sk->sk_bound_dev_if = sdev->netdev->ifindex; + + rv = s->ops->bind(s, (struct sockaddr *)laddr, + sizeof(struct sockaddr_in)); + } else { + struct sockaddr_in6 *laddr = &to_sockaddr_in6(id->local_addr); + + /* For wildcard addr, limit binding to current device only */ + if (ipv6_addr_any(&laddr->sin6_addr)) + s->sk->sk_bound_dev_if = sdev->netdev->ifindex; + + rv = s->ops->bind(s, (struct sockaddr *)laddr, + sizeof(struct sockaddr_in6)); + } if (rv) { siw_dbg(id->device, "socket bind error: %d\n", rv); goto error; @@ -1852,7 +1877,7 @@ static int siw_listen_address(struct iw_ list_add_tail(&cep->listenq, (struct list_head *)id->provider_data); cep->state = SIW_EPSTATE_LISTENING;
- siw_dbg(id->device, "Listen at laddr %pISp\n", laddr); + siw_dbg(id->device, "Listen at laddr %pISp\n", &id->local_addr);
return 0;
@@ -1910,106 +1935,6 @@ static void siw_drop_listeners(struct iw } }
-/* - * siw_create_listen - Create resources for a listener's IWCM ID @id - * - * Listens on the socket address id->local_addr. - * - * If the listener's @id provides a specific local IP address, at most one - * listening socket is created and associated with @id. - * - * If the listener's @id provides the wildcard (zero) local IP address, - * a separate listen is performed for each local IP address of the device - * by creating a listening socket and binding to that local IP address. - * - */ -int siw_create_listen(struct iw_cm_id *id, int backlog) -{ - struct net_device *dev = to_siw_dev(id->device)->netdev; - int rv = 0, listeners = 0; - - siw_dbg(id->device, "backlog %d\n", backlog); - - /* - * For each attached address of the interface, create a - * listening socket, if id->local_addr is the wildcard - * IP address or matches the IP address. - */ - if (id->local_addr.ss_family == AF_INET) { - struct in_device *in_dev = in_dev_get(dev); - struct sockaddr_in s_laddr; - const struct in_ifaddr *ifa; - - if (!in_dev) { - rv = -ENODEV; - goto out; - } - memcpy(&s_laddr, &id->local_addr, sizeof(s_laddr)); - - siw_dbg(id->device, "laddr %pISp\n", &s_laddr); - - rtnl_lock(); - in_dev_for_each_ifa_rtnl(ifa, in_dev) { - if (ipv4_is_zeronet(s_laddr.sin_addr.s_addr) || - s_laddr.sin_addr.s_addr == ifa->ifa_address) { - s_laddr.sin_addr.s_addr = ifa->ifa_address; - - rv = siw_listen_address(id, backlog, - (struct sockaddr *)&s_laddr, - AF_INET); - if (!rv) - listeners++; - } - } - rtnl_unlock(); - in_dev_put(in_dev); - } else if (id->local_addr.ss_family == AF_INET6) { - struct inet6_dev *in6_dev = in6_dev_get(dev); - struct inet6_ifaddr *ifp; - struct sockaddr_in6 *s_laddr = &to_sockaddr_in6(id->local_addr); - - if (!in6_dev) { - rv = -ENODEV; - goto out; - } - siw_dbg(id->device, "laddr %pISp\n", &s_laddr); - - rtnl_lock(); - list_for_each_entry(ifp, &in6_dev->addr_list, if_list) { - if (ifp->flags & (IFA_F_TENTATIVE | IFA_F_DEPRECATED)) - continue; - if (ipv6_addr_any(&s_laddr->sin6_addr) || - ipv6_addr_equal(&s_laddr->sin6_addr, &ifp->addr)) { - struct sockaddr_in6 bind_addr = { - .sin6_family = AF_INET6, - .sin6_port = s_laddr->sin6_port, - .sin6_flowinfo = 0, - .sin6_addr = ifp->addr, - .sin6_scope_id = dev->ifindex }; - - rv = siw_listen_address(id, backlog, - (struct sockaddr *)&bind_addr, - AF_INET6); - if (!rv) - listeners++; - } - } - rtnl_unlock(); - in6_dev_put(in6_dev); - } else { - rv = -EAFNOSUPPORT; - } -out: - if (listeners) - rv = 0; - else if (!rv) - rv = -EINVAL; - - siw_dbg(id->device, "%s\n", rv ? "FAIL" : "OK"); - - return rv; -} - int siw_destroy_listen(struct iw_cm_id *id) { if (!id->provider_data) {