From 8d037973d48c026224ab285e6a06985ccac6f7bf Mon Sep 17 00:00:00 2001
From: Patrisious Haddad <phaddad@nvidia.com>
Date: Wed, 4 Jan 2023 10:01:38 +0200
Subject: [PATCH 1/1] RDMA/core: Refactor rdma_bind_addr
Git-commit: 8d037973d48c026224ab285e6a06985ccac6f7bf
Patch-mainline: v6.3-rc1
References: bsc#1210629 CVE-2023-2176

Refactor rdma_bind_addr function so that it doesn't require that the
cma destination address be changed before calling it.

So now it will update the destination address internally only when it is
really needed and after passing all the required checks.

Which in turn results in a cleaner and more sensible call and error
handling flows for the functions that call it directly or indirectly.

Signed-off-by: Patrisious Haddad <phaddad@nvidia.com>
Reported-by: Wei Chen <harperchen1110@gmail.com>
Reviewed-by: Mark Zhang <markzhang@nvidia.com>
Link: https://lore.kernel.org/r/3d0e9a2fd62bc10ba02fed1c7c48a48638952320.1672819273.git.leonro@nvidia.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Acked-by: Nicolas Morey <nmorey@suse.com>
---
 drivers/infiniband/core/cma.c | 253 +++++++++++++++++-----------------
 1 file changed, 130 insertions(+), 123 deletions(-)

diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c
index 68721ff10255..b9da636fe1fb 100644
--- a/drivers/infiniband/core/cma.c
+++ b/drivers/infiniband/core/cma.c
@@ -3541,122 +3541,6 @@ err:
 	return ret;
 }
 
-static int cma_bind_addr(struct rdma_cm_id *id, struct sockaddr *src_addr,
-			 struct sockaddr *dst_addr)
-{
-	struct sockaddr_storage zero_sock = {};
-
-	if (src_addr && src_addr->sa_family)
-		return rdma_bind_addr(id, src_addr);
-
-	/*
-	 * When the src_addr is not specified, automatically supply an any addr
-	 */
-	zero_sock.ss_family = dst_addr->sa_family;
-	if (IS_ENABLED(CONFIG_IPV6) && dst_addr->sa_family == AF_INET6) {
-		struct sockaddr_in6 *src_addr6 =
-			(struct sockaddr_in6 *)&zero_sock;
-		struct sockaddr_in6 *dst_addr6 =
-			(struct sockaddr_in6 *)dst_addr;
-
-		src_addr6->sin6_scope_id = dst_addr6->sin6_scope_id;
-		if (ipv6_addr_type(&dst_addr6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
-			id->route.addr.dev_addr.bound_dev_if =
-				dst_addr6->sin6_scope_id;
-	} else if (dst_addr->sa_family == AF_IB) {
-		((struct sockaddr_ib *)&zero_sock)->sib_pkey =
-			((struct sockaddr_ib *)dst_addr)->sib_pkey;
-	}
-	return rdma_bind_addr(id, (struct sockaddr *)&zero_sock);
-}
-
-/*
- * If required, resolve the source address for bind and leave the id_priv in
- * state RDMA_CM_ADDR_BOUND. This oddly uses the state to determine the prior
- * calls made by ULP, a previously bound ID will not be re-bound and src_addr is
- * ignored.
- */
-static int resolve_prepare_src(struct rdma_id_private *id_priv,
-			       struct sockaddr *src_addr,
-			       struct sockaddr *dst_addr)
-{
-	int ret;
-
-	memcpy(cma_dst_addr(id_priv), dst_addr, rdma_addr_size(dst_addr));
-	if (!cma_comp_exch(id_priv, RDMA_CM_ADDR_BOUND, RDMA_CM_ADDR_QUERY)) {
-		/* For a well behaved ULP state will be RDMA_CM_IDLE */
-		ret = cma_bind_addr(&id_priv->id, src_addr, dst_addr);
-		if (ret)
-			goto err_dst;
-		if (WARN_ON(!cma_comp_exch(id_priv, RDMA_CM_ADDR_BOUND,
-					   RDMA_CM_ADDR_QUERY))) {
-			ret = -EINVAL;
-			goto err_dst;
-		}
-	}
-
-	if (cma_family(id_priv) != dst_addr->sa_family) {
-		ret = -EINVAL;
-		goto err_state;
-	}
-	return 0;
-
-err_state:
-	cma_comp_exch(id_priv, RDMA_CM_ADDR_QUERY, RDMA_CM_ADDR_BOUND);
-err_dst:
-	memset(cma_dst_addr(id_priv), 0, rdma_addr_size(dst_addr));
-	return ret;
-}
-
-int rdma_resolve_addr(struct rdma_cm_id *id, struct sockaddr *src_addr,
-		      struct sockaddr *dst_addr, int timeout_ms)
-{
-	struct rdma_id_private *id_priv =
-		container_of(id, struct rdma_id_private, id);
-	int ret;
-
-	ret = resolve_prepare_src(id_priv, src_addr, dst_addr);
-	if (ret)
-		return ret;
-
-	atomic_inc(&id_priv->refcount);
-	if (cma_any_addr(dst_addr)) {
-		ret = cma_resolve_loopback(id_priv);
-	} else {
-		if (dst_addr->sa_family == AF_IB) {
-			ret = cma_resolve_ib_addr(id_priv);
-		} else {
-			/*
-			 * The FSM can return back to RDMA_CM_ADDR_BOUND after
-			 * rdma_resolve_ip() is called, eg through the error
-			 * path in addr_handler(). If this happens the existing
-			 * request must be canceled before issuing a new one.
-			 * Since canceling a request is a bit slow and this
-			 * oddball path is rare, keep track once a request has
-			 * been issued. The track turns out to be a permanent
-			 * state since this is the only cancel as it is
-			 * immediately before rdma_resolve_ip().
-			 */
-			if (id_priv->used_resolve_ip)
-				rdma_addr_cancel(&id->route.addr.dev_addr);
-			else
-				id_priv->used_resolve_ip = 1;
-			ret = rdma_resolve_ip(&addr_client, cma_src_addr(id_priv),
-					      dst_addr, &id->route.addr.dev_addr,
-					      timeout_ms, addr_handler, id_priv);
-		}
-	}
-	if (ret)
-		goto err;
-
-	return 0;
-err:
-	cma_comp_exch(id_priv, RDMA_CM_ADDR_QUERY, RDMA_CM_ADDR_BOUND);
-	cma_deref_id(id_priv);
-	return ret;
-}
-EXPORT_SYMBOL(rdma_resolve_addr);
-
 int rdma_set_reuseaddr(struct rdma_cm_id *id, int reuse)
 {
 	struct rdma_id_private *id_priv;
@@ -4058,27 +3943,26 @@ err:
 }
 EXPORT_SYMBOL(rdma_listen);
 
-int rdma_bind_addr(struct rdma_cm_id *id, struct sockaddr *addr)
+static int rdma_bind_addr_dst(struct rdma_id_private *id_priv,
+			      struct sockaddr *addr, const struct sockaddr *daddr)
 {
-	struct rdma_id_private *id_priv;
+	struct sockaddr *id_daddr;
 	int ret;
-	struct sockaddr  *daddr;
 
 	if (addr->sa_family != AF_INET && addr->sa_family != AF_INET6 &&
 	    addr->sa_family != AF_IB)
 		return -EAFNOSUPPORT;
 
-	id_priv = container_of(id, struct rdma_id_private, id);
 	if (!cma_comp_exch(id_priv, RDMA_CM_IDLE, RDMA_CM_ADDR_BOUND))
 		return -EINVAL;
 
-	ret = cma_check_linklocal(&id->route.addr.dev_addr, addr);
+	ret = cma_check_linklocal(&id_priv->id.route.addr.dev_addr, addr);
 	if (ret)
 		goto err1;
 
 	memcpy(cma_src_addr(id_priv), addr, rdma_addr_size(addr));
 	if (!cma_any_addr(addr)) {
-		ret = cma_translate_addr(addr, &id->route.addr.dev_addr);
+		ret = cma_translate_addr(addr, &id_priv->id.route.addr.dev_addr);
 		if (ret)
 			goto err1;
 
@@ -4098,8 +3982,10 @@ int rdma_bind_addr(struct rdma_cm_id *id, struct sockaddr *addr)
 		}
 #endif
 	}
-	daddr = cma_dst_addr(id_priv);
-	daddr->sa_family = addr->sa_family;
+	id_daddr = cma_dst_addr(id_priv);
+	if (daddr != id_daddr)
+		memcpy(id_daddr, daddr, rdma_addr_size(addr));
+	id_daddr->sa_family = addr->sa_family;
 
 	ret = cma_get_port(id_priv);
 	if (ret)
@@ -4115,6 +4001,126 @@ err1:
 	cma_comp_exch(id_priv, RDMA_CM_ADDR_BOUND, RDMA_CM_IDLE);
 	return ret;
 }
+
+static int cma_bind_addr(struct rdma_cm_id *id, struct sockaddr *src_addr,
+			 const struct sockaddr *dst_addr)
+{
+	struct rdma_id_private *id_priv =
+		container_of(id, struct rdma_id_private, id);
+	struct sockaddr_storage zero_sock = {};
+
+	if (src_addr && src_addr->sa_family)
+		return rdma_bind_addr_dst(id_priv, src_addr, dst_addr);
+
+	/*
+	 * When the src_addr is not specified, automatically supply an any addr
+	 */
+	zero_sock.ss_family = dst_addr->sa_family;
+	if (IS_ENABLED(CONFIG_IPV6) && dst_addr->sa_family == AF_INET6) {
+		struct sockaddr_in6 *src_addr6 =
+			(struct sockaddr_in6 *)&zero_sock;
+		struct sockaddr_in6 *dst_addr6 =
+			(struct sockaddr_in6 *)dst_addr;
+
+		src_addr6->sin6_scope_id = dst_addr6->sin6_scope_id;
+		if (ipv6_addr_type(&dst_addr6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
+			id->route.addr.dev_addr.bound_dev_if =
+				dst_addr6->sin6_scope_id;
+	} else if (dst_addr->sa_family == AF_IB) {
+		((struct sockaddr_ib *)&zero_sock)->sib_pkey =
+			((struct sockaddr_ib *)dst_addr)->sib_pkey;
+	}
+	return rdma_bind_addr_dst(id_priv, (struct sockaddr *)&zero_sock, dst_addr);
+}
+
+/*
+ * If required, resolve the source address for bind and leave the id_priv in
+ * state RDMA_CM_ADDR_BOUND. This oddly uses the state to determine the prior
+ * calls made by ULP, a previously bound ID will not be re-bound and src_addr is
+ * ignored.
+ */
+static int resolve_prepare_src(struct rdma_id_private *id_priv,
+			       struct sockaddr *src_addr,
+			       const struct sockaddr *dst_addr)
+{
+	int ret;
+
+	if (!cma_comp_exch(id_priv, RDMA_CM_ADDR_BOUND, RDMA_CM_ADDR_QUERY)) {
+		/* For a well behaved ULP state will be RDMA_CM_IDLE */
+		ret = cma_bind_addr(&id_priv->id, src_addr, dst_addr);
+		if (ret)
+			return ret;
+		if (WARN_ON(!cma_comp_exch(id_priv, RDMA_CM_ADDR_BOUND,
+					   RDMA_CM_ADDR_QUERY)))
+			return -EINVAL;
+
+	}
+
+	if (cma_family(id_priv) != dst_addr->sa_family) {
+		ret = -EINVAL;
+		goto err_state;
+	}
+	return 0;
+
+err_state:
+	cma_comp_exch(id_priv, RDMA_CM_ADDR_QUERY, RDMA_CM_ADDR_BOUND);
+	return ret;
+}
+
+int rdma_resolve_addr(struct rdma_cm_id *id, struct sockaddr *src_addr,
+		      struct sockaddr *dst_addr, int timeout_ms)
+{
+	struct rdma_id_private *id_priv =
+		container_of(id, struct rdma_id_private, id);
+	int ret;
+
+	ret = resolve_prepare_src(id_priv, src_addr, dst_addr);
+	if (ret)
+		return ret;
+
+	if (cma_any_addr(dst_addr)) {
+		ret = cma_resolve_loopback(id_priv);
+	} else {
+		if (dst_addr->sa_family == AF_IB) {
+			ret = cma_resolve_ib_addr(id_priv);
+		} else {
+			/*
+			 * The FSM can return back to RDMA_CM_ADDR_BOUND after
+			 * rdma_resolve_ip() is called, eg through the error
+			 * path in addr_handler(). If this happens the existing
+			 * request must be canceled before issuing a new one.
+			 * Since canceling a request is a bit slow and this
+			 * oddball path is rare, keep track once a request has
+			 * been issued. The track turns out to be a permanent
+			 * state since this is the only cancel as it is
+			 * immediately before rdma_resolve_ip().
+			 */
+			if (id_priv->used_resolve_ip)
+				rdma_addr_cancel(&id->route.addr.dev_addr);
+			else
+				id_priv->used_resolve_ip = 1;
+			ret = rdma_resolve_ip(&addr_client, cma_src_addr(id_priv),
+					      dst_addr, &id->route.addr.dev_addr,
+					      timeout_ms, addr_handler, id_priv);
+		}
+	}
+	if (ret)
+		goto err;
+
+	return 0;
+err:
+	cma_comp_exch(id_priv, RDMA_CM_ADDR_QUERY, RDMA_CM_ADDR_BOUND);
+	return ret;
+}
+EXPORT_SYMBOL(rdma_resolve_addr);
+
+int rdma_bind_addr(struct rdma_cm_id *id, struct sockaddr *addr)
+{
+	struct rdma_id_private *id_priv =
+		container_of(id, struct rdma_id_private, id);
+
+	return rdma_bind_addr_dst(id_priv, addr, cma_dst_addr(id_priv));
+}
 EXPORT_SYMBOL(rdma_bind_addr);
 
 static int cma_format_hdr(void *hdr, struct rdma_id_private *id_priv)
-- 
2.39.1.1.gbe015eda0162