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: 790071347a0a ("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: Paul Fertser <fercerpav@gmail.com>
Tested-by: Potin Lai <potin.lai.pt@gmail.com>
Link: https://patch.msgid.link/20250109145054.30925-1-fercerpav@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/net/ncsi/internal.h b/net/ncsi/internal.h
index ef0f8f73826f53b8995b7b11ae13da5f3bf82af9..4e0842df5234ea0478bd9fb455b60df693b624ae 100644 (file)
--- a/net/ncsi/internal.h
+++ b/net/ncsi/internal.h
@@ -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         */

diff --git a/net/ncsi/ncsi-manage.c b/net/ncsi/ncsi-manage.c
index 5cf55bde366d1813865ac5da17d232b5eadb2a3e..bf276eaf93307511ce36d026a02ded6db32a4f88 100644 (file)
--- a/net/ncsi/ncsi-manage.c
+++ b/net/ncsi/ncsi-manage.c
@@ -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:

diff --git a/net/ncsi/ncsi-rsp.c b/net/ncsi/ncsi-rsp.c
index e28be33bdf2c487c0fbfe3a1b4de6f52c8f923cc..14bd66909ca4553b92f04c6308bd7630dbd8c653 100644 (file)
--- a/net/ncsi/ncsi-rsp.c
+++ b/net/ncsi/ncsi-rsp.c
@@ -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 */