Commit 9e2bbab9 authored by Paul Fertser's avatar Paul Fertser Committed by Jakub Kicinski
Browse files

net/ncsi: fix locking in Get MAC Address handling 

Obtaining RTNL lock in a response handler is not allowed since it runs
in an atomic softirq context. Postpone setting the MAC address by adding
a dedicated step to the configuration FSM.

Fixes: 79007134 ("net/ncsi: change from ndo_set_mac_address to dev_set_mac_address")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/20241129-potin-revert-ncsi-set-mac-addr-v1-1-94ea2cb596af@gmail.com


Signed-off-by: default avatarPaul Fertser <fercerpav@gmail.com>
Tested-by: default avatarPotin Lai <potin.lai.pt@gmail.com>
Link: https://patch.msgid.link/20250109145054.30925-1-fercerpav@gmail.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 76201b59

net/ncsi/internal.h

+2 −0
Original line number Diff line number Diff line
@@ -289,6 +289,7 @@ enum { 
	ncsi_dev_state_config_sp	= 0x0301,

	ncsi_dev_state_config_cis,

	ncsi_dev_state_config_oem_gma,

	ncsi_dev_state_config_apply_mac,

	ncsi_dev_state_config_clear_vids,

	ncsi_dev_state_config_svf,

	ncsi_dev_state_config_ev,
@@ -322,6 +323,7 @@ struct ncsi_dev_priv { 
#define NCSI_DEV_RESHUFFLE	4

#define NCSI_DEV_RESET		8            /* Reset state of NC          */

	unsigned int        gma_flag;        /* OEM GMA flag               */

	struct sockaddr     pending_mac;     /* MAC address received from GMA */

	spinlock_t          lock;            /* Protect the NCSI device    */

	unsigned int        package_probe_id;/* Current ID during probe    */

	unsigned int        package_num;     /* Number of packages         */

net/ncsi/ncsi-manage.c

+14 −2
Original line number Diff line number Diff line
@@ -1038,7 +1038,7 @@ static void ncsi_configure_channel(struct ncsi_dev_priv *ndp) 
			  : ncsi_dev_state_config_clear_vids;

		break;

	case ncsi_dev_state_config_oem_gma:

		nd->state = ncsi_dev_state_config_clear_vids;

		nd->state = ncsi_dev_state_config_apply_mac;



		nca.package = np->id;

		nca.channel = nc->id;
@@ -1050,10 +1050,22 @@ static void ncsi_configure_channel(struct ncsi_dev_priv *ndp) 
			nca.type = NCSI_PKT_CMD_OEM;

			ret = ncsi_gma_handler(&nca, nc->version.mf_id);

		}

		if (ret < 0)

		if (ret < 0) {

			nd->state = ncsi_dev_state_config_clear_vids;

			schedule_work(&ndp->work);

		}



		break;

	case ncsi_dev_state_config_apply_mac:

		rtnl_lock();

		ret = dev_set_mac_address(dev, &ndp->pending_mac, NULL);

		rtnl_unlock();

		if (ret < 0)

			netdev_warn(dev, "NCSI: 'Writing MAC address to device failed\n");



		nd->state = ncsi_dev_state_config_clear_vids;



		fallthrough;

	case ncsi_dev_state_config_clear_vids:

	case ncsi_dev_state_config_svf:

	case ncsi_dev_state_config_ev:

net/ncsi/ncsi-rsp.c

+6 −13
Original line number Diff line number Diff line
@@ -628,16 +628,14 @@ static int ncsi_rsp_handler_snfc(struct ncsi_request *nr) 
static int ncsi_rsp_handler_oem_gma(struct ncsi_request *nr, int mfr_id)

{

	struct ncsi_dev_priv *ndp = nr->ndp;

	struct sockaddr *saddr = &ndp->pending_mac;

	struct net_device *ndev = ndp->ndev.dev;

	struct ncsi_rsp_oem_pkt *rsp;

	struct sockaddr saddr;

	u32 mac_addr_off = 0;

	int ret = 0;



	/* Get the response header */

	rsp = (struct ncsi_rsp_oem_pkt *)skb_network_header(nr->rsp);



	saddr.sa_family = ndev->type;

	ndev->priv_flags |= IFF_LIVE_ADDR_CHANGE;

	if (mfr_id == NCSI_OEM_MFR_BCM_ID)

		mac_addr_off = BCM_MAC_ADDR_OFFSET;
@@ -646,22 +644,17 @@ static int ncsi_rsp_handler_oem_gma(struct ncsi_request *nr, int mfr_id) 
	else if (mfr_id == NCSI_OEM_MFR_INTEL_ID)

		mac_addr_off = INTEL_MAC_ADDR_OFFSET;



	memcpy(saddr.sa_data, &rsp->data[mac_addr_off], ETH_ALEN);

	saddr->sa_family = ndev->type;

	memcpy(saddr->sa_data, &rsp->data[mac_addr_off], ETH_ALEN);

	if (mfr_id == NCSI_OEM_MFR_BCM_ID || mfr_id == NCSI_OEM_MFR_INTEL_ID)

		eth_addr_inc((u8 *)saddr.sa_data);

	if (!is_valid_ether_addr((const u8 *)saddr.sa_data))

		eth_addr_inc((u8 *)saddr->sa_data);

	if (!is_valid_ether_addr((const u8 *)saddr->sa_data))

		return -ENXIO;



	/* Set the flag for GMA command which should only be called once */

	ndp->gma_flag = 1;



	rtnl_lock();

	ret = dev_set_mac_address(ndev, &saddr, NULL);

	rtnl_unlock();

	if (ret < 0)

		netdev_warn(ndev, "NCSI: 'Writing mac address to device failed\n");



	return ret;

	return 0;

}



/* Response handler for Mellanox card */