From 17109e9783799be2a063b2bd861a508194b0a487 Mon Sep 17 00:00:00 2001 From: Matteo Croce Date: Tue, 6 Jul 2021 17:44:23 +0200 Subject: [PATCH] virt_wifi: fix error on connect When connecting without first doing a scan, the BSS list is empty and __cfg80211_connect_result() generates this warning: $ iw dev wlan0 connect -w VirtWifi [ 15.371989] ------------[ cut here ]------------ [ 15.372179] WARNING: CPU: 0 PID: 92 at net/wireless/sme.c:756 __cfg80211_connect_result+0x402/0x440 [ 15.372383] CPU: 0 PID: 92 Comm: kworker/u2:2 Not tainted 5.13.0-kvm #444 [ 15.372512] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-3.fc34 04/01/2014 [ 15.372597] Workqueue: cfg80211 cfg80211_event_work [ 15.372756] RIP: 0010:__cfg80211_connect_result+0x402/0x440 [ 15.372818] Code: 48 2b 04 25 28 00 00 00 75 59 48 8b 3b 48 8b 76 10 48 8d 65 e0 5b 41 5c 41 5d 41 5e 5d 49 8d 65 f0 41 5d e9 d0 d4 fd ff 0f 0b <0f> 0b e9 f6 fd ff ff e8 f2 4a b4 ff e9 ec fd ff ff 0f 0b e9 19 fd [ 15.372966] RSP: 0018:ffffc900005cbdc0 EFLAGS: 00010246 [ 15.373022] RAX: 0000000000000000 RBX: ffff8880028e2400 RCX: ffff8880028e2472 [ 15.373088] RDX: 0000000000000002 RSI: 00000000fffffe01 RDI: ffffffff815335ba [ 15.373149] RBP: ffffc900005cbe00 R08: 0000000000000008 R09: ffff888002bdf8b8 [ 15.373209] R10: ffff88803ec208f0 R11: ffffffffffffe9ae R12: ffff88801d687d98 [ 15.373280] R13: ffff88801b5fe000 R14: ffffc900005cbdc0 R15: dead000000000100 [ 15.373330] FS: 0000000000000000(0000) GS:ffff88803ec00000(0000) knlGS:0000000000000000 [ 15.373382] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 15.373425] CR2: 000056421c468958 CR3: 000000001b458001 CR4: 0000000000170eb0 [ 15.373478] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 15.373529] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 15.373580] Call Trace: [ 15.373611] ? cfg80211_process_wdev_events+0x10e/0x170 [ 15.373743] cfg80211_process_wdev_events+0x10e/0x170 [ 15.373783] cfg80211_process_rdev_events+0x21/0x40 [ 15.373846] cfg80211_event_work+0x20/0x30 [ 15.373892] process_one_work+0x1e9/0x340 [ 15.373956] worker_thread+0x4b/0x3f0 [ 15.374017] ? process_one_work+0x340/0x340 [ 15.374053] kthread+0x11f/0x140 [ 15.374089] ? set_kthread_struct+0x30/0x30 [ 15.374153] ret_from_fork+0x1f/0x30 [ 15.374187] ---[ end trace 321ef0cb7e9c0be1 ]--- wlan0 (phy #0): connected to 00:00:00:00:00:00 Add the fake bss just before the connect so that cfg80211_get_bss() finds the virtual network. As some code was duplicated, move it in a common function. Signed-off-by: Matteo Croce Link: https://lore.kernel.org/r/20210706154423.11065-1-mcroce@linux.microsoft.com Signed-off-by: Johannes Berg --- drivers/net/wireless/virt_wifi.c | 52 ++++++++++++++++++++------------ 1 file changed, 32 insertions(+), 20 deletions(-) diff --git a/drivers/net/wireless/virt_wifi.c b/drivers/net/wireless/virt_wifi.c index 1df959532c7d..514f2c1124b6 100644 --- a/drivers/net/wireless/virt_wifi.c +++ b/drivers/net/wireless/virt_wifi.c @@ -136,6 +136,29 @@ static struct ieee80211_supported_band band_5ghz = { /* Assigned at module init. Guaranteed locally-administered and unicast. */ static u8 fake_router_bssid[ETH_ALEN] __ro_after_init = {}; +static void virt_wifi_inform_bss(struct wiphy *wiphy) +{ + u64 tsf = div_u64(ktime_get_boottime_ns(), 1000); + struct cfg80211_bss *informed_bss; + static const struct { + u8 tag; + u8 len; + u8 ssid[8]; + } __packed ssid = { + .tag = WLAN_EID_SSID, + .len = 8, + .ssid = "VirtWifi", + }; + + informed_bss = cfg80211_inform_bss(wiphy, &channel_5ghz, + CFG80211_BSS_FTYPE_PRESP, + fake_router_bssid, tsf, + WLAN_CAPABILITY_ESS, 0, + (void *)&ssid, sizeof(ssid), + DBM_TO_MBM(-50), GFP_KERNEL); + cfg80211_put_bss(wiphy, informed_bss); +} + /* Called with the rtnl lock held. */ static int virt_wifi_scan(struct wiphy *wiphy, struct cfg80211_scan_request *request) @@ -156,28 +179,13 @@ static int virt_wifi_scan(struct wiphy *wiphy, /* Acquires and releases the rdev BSS lock. */ static void virt_wifi_scan_result(struct work_struct *work) { - struct { - u8 tag; - u8 len; - u8 ssid[8]; - } __packed ssid = { - .tag = WLAN_EID_SSID, .len = 8, .ssid = "VirtWifi", - }; - struct cfg80211_bss *informed_bss; struct virt_wifi_wiphy_priv *priv = container_of(work, struct virt_wifi_wiphy_priv, scan_result.work); struct wiphy *wiphy = priv_to_wiphy(priv); struct cfg80211_scan_info scan_info = { .aborted = false }; - u64 tsf = div_u64(ktime_get_boottime_ns(), 1000); - informed_bss = cfg80211_inform_bss(wiphy, &channel_5ghz, - CFG80211_BSS_FTYPE_PRESP, - fake_router_bssid, tsf, - WLAN_CAPABILITY_ESS, 0, - (void *)&ssid, sizeof(ssid), - DBM_TO_MBM(-50), GFP_KERNEL); - cfg80211_put_bss(wiphy, informed_bss); + virt_wifi_inform_bss(wiphy); /* Schedules work which acquires and releases the rtnl lock. */ cfg80211_scan_done(priv->scan_request, &scan_info); @@ -225,10 +233,12 @@ static int virt_wifi_connect(struct wiphy *wiphy, struct net_device *netdev, if (!could_schedule) return -EBUSY; - if (sme->bssid) + if (sme->bssid) { ether_addr_copy(priv->connect_requested_bss, sme->bssid); - else + } else { + virt_wifi_inform_bss(wiphy); eth_zero_addr(priv->connect_requested_bss); + } wiphy_debug(wiphy, "connect\n"); @@ -241,11 +251,13 @@ static void virt_wifi_connect_complete(struct work_struct *work) struct virt_wifi_netdev_priv *priv = container_of(work, struct virt_wifi_netdev_priv, connect.work); u8 *requested_bss = priv->connect_requested_bss; - bool has_addr = !is_zero_ether_addr(requested_bss); bool right_addr = ether_addr_equal(requested_bss, fake_router_bssid); u16 status = WLAN_STATUS_SUCCESS; - if (!priv->is_up || (has_addr && !right_addr)) + if (is_zero_ether_addr(requested_bss)) + requested_bss = NULL; + + if (!priv->is_up || (requested_bss && !right_addr)) status = WLAN_STATUS_UNSPECIFIED_FAILURE; else priv->is_connected = true;