[PATCH net] bnge: skip dev_addr when building the VNIC unicast list

[PATCH net] bnge: skip dev_addr when building the VNIC unicast list

[Vikas Gupta]

The default VNIC programs the device's MAC as L2 filter 0 in
bnge_init_chip() via bnge_hwrm_set_vnic_filter(bn, 0, 0, dev_addr).
bnge_cfg_rx_mode() then walks dev->uc and programs each unicast
address as a further L2 filter, without excluding dev_addr.

Skip dev_addr when building uc_list, since it is already installed as
filter 0. As dev_addr now takes neither a uc_list slot nor an
l2_filters[] slot, count only the non-dev_addr entries for the
uc_list overflow check too, otherwise an input such as
{dev_addr, A, B, C} would needlessly fall back to promiscuous mode
even though A, B and C fit in exact-match filters.
bnge_uc_list_updated() applies the same skip and count so the
change detection stays consistent and does not loop.

This issue was caught by Sashiko (nipa).

Tested on Thor Ultra device.

Fixes: 9afad4a17174 ("bng_en: Configure default VNIC")
Signed-off-by: Vikas Gupta <vikas.gupta@broadcom.com>
Reviewed-by: Dharmender Garg <dharmender.garg@broadcom.com>
---
 .../net/ethernet/broadcom/bnge/bnge_netdev.c  | 28 +++++++++++++------
 1 file changed, 20 insertions(+), 8 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/bnge/bnge_netdev.c b/drivers/net/ethernet/broadcom/bnge/bnge_netdev.c
index a4288f0258f8..92aea6f6f09f 100644
--- a/drivers/net/ethernet/broadcom/bnge/bnge_netdev.c
+++ b/drivers/net/ethernet/broadcom/bnge/bnge_netdev.c
@@ -2182,19 +2182,21 @@ static bool bnge_uc_list_updated(struct bnge_net *bn,
 				 const struct netdev_hw_addr_list *uc)
 {
 	struct bnge_vnic_info *vnic = &bn->vnic_info[BNGE_VNIC_DEFAULT];
+	struct net_device *dev = bn->netdev;
 	struct netdev_hw_addr *ha;
-	int off = 0;
-
-	if (netdev_hw_addr_list_count(uc) != (vnic->uc_filter_count - 1))
-		return true;
+	int off = 0, count = 0;
 
 	netdev_hw_addr_list_for_each(ha, uc) {
+		if (ether_addr_equal(ha->addr, dev->dev_addr))
+			continue;
+		if (count >= vnic->uc_filter_count - 1)
+			return true;
 		if (!ether_addr_equal(ha->addr, vnic->uc_list + off))
 			return true;
-
 		off += ETH_ALEN;
+		count++;
 	}
-	return false;
+	return count != vnic->uc_filter_count - 1;
 }
 
 static bool bnge_promisc_ok(struct bnge_net *bn)
@@ -2207,9 +2209,9 @@ static int bnge_cfg_rx_mode(struct bnge_net *bn, struct netdev_hw_addr_list *uc,
 {
 	struct bnge_vnic_info *vnic = &bn->vnic_info[BNGE_VNIC_DEFAULT];
 	struct net_device *dev = bn->netdev;
+	int i, off = 0, rc, uc_count = 0;
 	struct bnge_dev *bd = bn->bd;
 	struct netdev_hw_addr *ha;
-	int i, off = 0, rc;
 
 	if (!uc_update)
 		goto skip_uc;
@@ -2225,10 +2227,20 @@ static int bnge_cfg_rx_mode(struct bnge_net *bn, struct netdev_hw_addr_list *uc,
 
 	if (!snapshot)
 		netif_addr_lock_bh(dev);
-	if (netdev_hw_addr_list_count(uc) > (BNGE_MAX_UC_ADDRS - 1)) {
+	/* dev_addr is already programmed as L2 filter 0, so it takes neither a
+	 * uc_list slot nor an l2_filters[] slot. Count only the entries that
+	 * will actually be programmed so the overflow check matches the fill
+	 * loop below (and bnge_uc_list_updated()).
+	 */
+	netdev_hw_addr_list_for_each(ha, uc)
+		if (!ether_addr_equal(ha->addr, dev->dev_addr))
+			uc_count++;
+	if (uc_count > BNGE_MAX_UC_ADDRS - 1) {
 		vnic->rx_mask |= CFA_L2_SET_RX_MASK_REQ_MASK_PROMISCUOUS;
 	} else {
 		netdev_hw_addr_list_for_each(ha, uc) {
+			if (ether_addr_equal(ha->addr, dev->dev_addr))
+				continue;
 			memcpy(vnic->uc_list + off, ha->addr, ETH_ALEN);
 			off += ETH_ALEN;
 			vnic->uc_filter_count++;
-- 
2.52.0

Re: [PATCH net] bnge: skip dev_addr when building the VNIC unicast list

[netdev-bot+sinfo]

Hi!

This is an automated message. This series looks like a fix, but its
commit messages seem to be missing some information:

 - Whether the issue was actually triggered, or is only theoretical
   (e.g. found by code inspection). If it was triggered please include
   the symptoms, like the stack trace or error messages.

Please do not repost the series just to address the above. Instead,
reply to this email with the missing information, so that reviewers
can take it into account. If the series needs another revision for
other reasons, please include the information in the commit messages
then.

The evaluation is done by an LLM so it may be wrong, if you think
that is the case please reply and explain.

Re: [PATCH net] bnge: skip dev_addr when building the VNIC unicast list

[Vikas Gupta]

[-- Attachment #1: Type: text/plain, Size: 904 bytes --]

Hi,
This issue was found during code inspection.

Thanks,
Vikas

On Tue, Oct 6, 2026 at 7:55 PM <netdev-bot+sinfo@kernel.org> wrote:
>
> Hi!
>
> This is an automated message. This series looks like a fix, but its
> commit messages seem to be missing some information:
>
>  - Whether the issue was actually triggered, or is only theoretical
>    (e.g. found by code inspection). If it was triggered please include
>    the symptoms, like the stack trace or error messages.
>
> Please do not repost the series just to address the above. Instead,
> reply to this email with the missing information, so that reviewers
> can take it into account. If the series needs another revision for
> other reasons, please include the information in the commit messages
> then.
>
> The evaluation is done by an LLM so it may be wrong, if you think
> that is the case please reply and explain.

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