From: Jakub Kicinski <kuba@kernel.org>
Date: Mon, 24 Mar 2025 22:45:33 +0000 (-0700)
Subject: net: protect rxq->mp_params with the instance lock
X-Git-Tag: v6.15-rc1~160^2~10^2
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=b52458652eca5a551ddb55605201b136f091b04d;p=thirdparty%2Fkernel%2Flinux.git

net: protect rxq->mp_params with the instance lock

Ensure that all accesses to mp_params are under the netdev
instance lock. The only change we need is to move
dev_memory_provider_uninstall() under the lock.

Appropriately swap the asserts.

Reviewed-by: Mina Almasry <almasrymina@google.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250324224537.248800-8-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---

diff --git a/net/core/dev.c b/net/core/dev.c
index ab74e1f005d2e..b597cc27a115c 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -10358,7 +10358,7 @@ u32 dev_get_min_mp_channel_count(const struct net_device *dev)
 {
 	int i;
 
-	ASSERT_RTNL();
+	netdev_ops_assert_locked(dev);
 
 	for (i = dev->real_num_rx_queues - 1; i >= 0; i--)
 		if (dev->_rx[i].mp_params.mp_priv)
@@ -11962,9 +11962,9 @@ void unregister_netdevice_many_notify(struct list_head *head,
 		dev_tcx_uninstall(dev);
 		netdev_lock_ops(dev);
 		dev_xdp_uninstall(dev);
+		dev_memory_provider_uninstall(dev);
 		netdev_unlock_ops(dev);
 		bpf_dev_bound_netdev_unregister(dev);
-		dev_memory_provider_uninstall(dev);
 
 		netdev_offload_xstats_disable_all(dev);
 
diff --git a/net/core/page_pool.c b/net/core/page_pool.c
index acef1fcd8ddcf..7745ad924ae2d 100644
--- a/net/core/page_pool.c
+++ b/net/core/page_pool.c
@@ -11,6 +11,7 @@
 #include <linux/slab.h>
 #include <linux/device.h>
 
+#include <net/netdev_lock.h>
 #include <net/netdev_rx_queue.h>
 #include <net/page_pool/helpers.h>
 #include <net/page_pool/memory_provider.h>
@@ -279,11 +280,7 @@ static int page_pool_init(struct page_pool *pool,
 		get_device(pool->p.dev);
 
 	if (pool->slow.flags & PP_FLAG_ALLOW_UNREADABLE_NETMEM) {
-		/* We rely on rtnl_lock()ing to make sure netdev_rx_queue
-		 * configuration doesn't change while we're initializing
-		 * the page_pool.
-		 */
-		ASSERT_RTNL();
+		netdev_assert_locked(pool->slow.netdev);
 		rxq = __netif_get_rx_queue(pool->slow.netdev,
 					   pool->slow.queue_idx);
 		pool->mp_priv = rxq->mp_params.mp_priv;