[PATCH AUTOSEL 6.6 38/83] bpf, net: Use DEV_STAT_INC()

[PATCH AUTOSEL 6.6 38/83] bpf, net: Use DEV_STAT_INC()

[Sasha Levin]

From: yunshui <jiangyunshui@kylinos.cn>

[ Upstream commit d9cbd8343b010016fcaabc361c37720dcafddcbe ]

syzbot/KCSAN reported that races happen when multiple CPUs updating
dev->stats.tx_error concurrently. Adopt SMP safe DEV_STATS_INC() to
update the dev->stats fields.

Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: yunshui <jiangyunshui@kylinos.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20240523033520.4029314-1-jiangyunshui@kylinos.cn
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/core/filter.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/net/core/filter.c b/net/core/filter.c
index afe38b8dee024..86aac8ccd855e 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -2271,12 +2271,12 @@ static int __bpf_redirect_neigh_v6(struct sk_buff *skb, struct net_device *dev,
 
 	err = bpf_out_neigh_v6(net, skb, dev, nh);
 	if (unlikely(net_xmit_eval(err)))
-		dev->stats.tx_errors++;
+		DEV_STATS_INC(dev, tx_errors);
 	else
 		ret = NET_XMIT_SUCCESS;
 	goto out_xmit;
 out_drop:
-	dev->stats.tx_errors++;
+	DEV_STATS_INC(dev, tx_errors);
 	kfree_skb(skb);
 out_xmit:
 	return ret;
@@ -2378,12 +2378,12 @@ static int __bpf_redirect_neigh_v4(struct sk_buff *skb, struct net_device *dev,
 
 	err = bpf_out_neigh_v4(net, skb, dev, nh);
 	if (unlikely(net_xmit_eval(err)))
-		dev->stats.tx_errors++;
+		DEV_STATS_INC(dev, tx_errors);
 	else
 		ret = NET_XMIT_SUCCESS;
 	goto out_xmit;
 out_drop:
-	dev->stats.tx_errors++;
+	DEV_STATS_INC(dev, tx_errors);
 	kfree_skb(skb);
 out_xmit:
 	return ret;
-- 
2.43.0

[PATCH AUTOSEL 6.6 49/83] wifi: cfg80211: make hash table duplicates more survivable

[Sasha Levin]

From: Johannes Berg <johannes.berg@intel.com>

[ Upstream commit 7f12e26a194d0043441f870708093d9c2c3bad7d ]

Jiazi Li reported that they occasionally see hash table duplicates
as evidenced by the WARN_ON() in rb_insert_bss() in this code.  It
isn't clear how that happens, nor have I been able to reproduce it,
but if it does happen, the kernel crashes later, when it tries to
unhash the entry that's now not hashed.

Try to make this situation more survivable by removing the BSS from
the list(s) as well, that way it's fully leaked here (as had been
the intent in the hash insert error path), and no longer reachable
through the list(s) so it shouldn't be unhashed again later.

Link: https://lore.kernel.org/r/20231026013528.GA24122@Jiazi.Li
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Link: https://msgid.link/20240607181726.36835-2-johannes@sipsolutions.net
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/wireless/scan.c | 46 +++++++++++++++++++++++++++++++++------------
 1 file changed, 34 insertions(+), 12 deletions(-)

diff --git a/net/wireless/scan.c b/net/wireless/scan.c
index 74db51348a7ff..4d88e797ae49f 100644
--- a/net/wireless/scan.c
+++ b/net/wireless/scan.c
@@ -1562,7 +1562,7 @@ struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy,
 }
 EXPORT_SYMBOL(cfg80211_get_bss);
 
-static void rb_insert_bss(struct cfg80211_registered_device *rdev,
+static bool rb_insert_bss(struct cfg80211_registered_device *rdev,
 			  struct cfg80211_internal_bss *bss)
 {
 	struct rb_node **p = &rdev->bss_tree.rb_node;
@@ -1578,7 +1578,7 @@ static void rb_insert_bss(struct cfg80211_registered_device *rdev,
 
 		if (WARN_ON(!cmp)) {
 			/* will sort of leak this BSS */
-			return;
+			return false;
 		}
 
 		if (cmp < 0)
@@ -1589,6 +1589,7 @@ static void rb_insert_bss(struct cfg80211_registered_device *rdev,
 
 	rb_link_node(&bss->rbn, parent, p);
 	rb_insert_color(&bss->rbn, &rdev->bss_tree);
+	return true;
 }
 
 static struct cfg80211_internal_bss *
@@ -1615,6 +1616,34 @@ rb_find_bss(struct cfg80211_registered_device *rdev,
 	return NULL;
 }
 
+static void cfg80211_insert_bss(struct cfg80211_registered_device *rdev,
+				struct cfg80211_internal_bss *bss)
+{
+	lockdep_assert_held(&rdev->bss_lock);
+
+	if (!rb_insert_bss(rdev, bss))
+		return;
+	list_add_tail(&bss->list, &rdev->bss_list);
+	rdev->bss_entries++;
+}
+
+static void cfg80211_rehash_bss(struct cfg80211_registered_device *rdev,
+                                struct cfg80211_internal_bss *bss)
+{
+	lockdep_assert_held(&rdev->bss_lock);
+
+	rb_erase(&bss->rbn, &rdev->bss_tree);
+	if (!rb_insert_bss(rdev, bss)) {
+		list_del(&bss->list);
+		if (!list_empty(&bss->hidden_list))
+			list_del_init(&bss->hidden_list);
+		if (!list_empty(&bss->pub.nontrans_list))
+			list_del_init(&bss->pub.nontrans_list);
+		rdev->bss_entries--;
+	}
+	rdev->bss_generation++;
+}
+
 static bool cfg80211_combine_bsses(struct cfg80211_registered_device *rdev,
 				   struct cfg80211_internal_bss *new)
 {
@@ -1876,9 +1905,7 @@ __cfg80211_bss_update(struct cfg80211_registered_device *rdev,
 			bss_ref_get(rdev, bss_from_pub(tmp->pub.transmitted_bss));
 		}
 
-		list_add_tail(&new->list, &rdev->bss_list);
-		rdev->bss_entries++;
-		rb_insert_bss(rdev, new);
+		cfg80211_insert_bss(rdev, new);
 		found = new;
 	}
 
@@ -3111,19 +3138,14 @@ void cfg80211_update_assoc_bss_entry(struct wireless_dev *wdev,
 		if (!WARN_ON(!__cfg80211_unlink_bss(rdev, new)))
 			rdev->bss_generation++;
 	}
-
-	rb_erase(&cbss->rbn, &rdev->bss_tree);
-	rb_insert_bss(rdev, cbss);
-	rdev->bss_generation++;
+	cfg80211_rehash_bss(rdev, cbss);
 
 	list_for_each_entry_safe(nontrans_bss, tmp,
 				 &cbss->pub.nontrans_list,
 				 nontrans_list) {
 		bss = bss_from_pub(nontrans_bss);
 		bss->pub.channel = chan;
-		rb_erase(&bss->rbn, &rdev->bss_tree);
-		rb_insert_bss(rdev, bss);
-		rdev->bss_generation++;
+		cfg80211_rehash_bss(rdev, bss);
 	}
 
 done:
-- 
2.43.0

[PATCH AUTOSEL 6.6 56/83] fou: remove warn in gue_gro_receive on unsupported protocol

[Sasha Levin]

From: Willem de Bruijn <willemb@google.com>

[ Upstream commit dd89a81d850fa9a65f67b4527c0e420d15bf836c ]

Drop the WARN_ON_ONCE inn gue_gro_receive if the encapsulated type is
not known or does not have a GRO handler.

Such a packet is easily constructed. Syzbot generates them and sets
off this warning.

Remove the warning as it is expected and not actionable.

The warning was previously reduced from WARN_ON to WARN_ON_ONCE in
commit 270136613bf7 ("fou: Do WARN_ON_ONCE in gue_gro_receive for bad
proto callbacks").

Signed-off-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240614122552.1649044-1-willemdebruijn.kernel@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/ipv4/fou_core.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/ipv4/fou_core.c b/net/ipv4/fou_core.c
index 0c41076e31eda..b38b82ae903de 100644
--- a/net/ipv4/fou_core.c
+++ b/net/ipv4/fou_core.c
@@ -433,7 +433,7 @@ static struct sk_buff *gue_gro_receive(struct sock *sk,
 
 	offloads = NAPI_GRO_CB(skb)->is_ipv6 ? inet6_offloads : inet_offloads;
 	ops = rcu_dereference(offloads[proto]);
-	if (WARN_ON_ONCE(!ops || !ops->callbacks.gro_receive))
+	if (!ops || !ops->callbacks.gro_receive)
 		goto out;
 
 	pp = call_gro_receive(ops->callbacks.gro_receive, head, skb);
-- 
2.43.0