From dca2307ed6250e7be6993e165570fa4097903a58 Mon Sep 17 00:00:00 2001 From: Arend Van Spriel Date: Sat, 24 Jun 2017 22:08:27 +0100 Subject: [PATCH] brcmfmac: fix double free upon register_netdevice() failure The function brcmf_net_attach() can only fail when register_netdevice() fails. When this happens register_netdevice() calls priv_destructor, ie. brcmf_cfg80211_free_netdev() freeing the vif instance. Also upon this failure brcmf_net_attach() calls free_netdev(). However, callers are also doing cleanup resulting in double free. In some places they need netdev private space as it holds parameters to communicate with the device. So we want to do the cleanup only in callers of brcmf_net_attach() by making the following changes: - set priv_destructor after register_netdevice() succeeds. - remove call to free_netdev() in brcmf_net_attach(). - call free_netdev() in brcmf_net_detach() for unregistered netdev. - add free_netdev() if brcmf_net_attach() fails for a created interface. Fixes: cf124db566e6 ("net: Fix inconsistent teardown and release of private netdev state.") Reviewed-by: Hante Meuleman Reviewed-by: Pieter-Paul Giesberts Reviewed-by: Franky Lin Signed-off-by: Arend van Spriel Signed-off-by: Kalle Valo --- drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c | 1 + drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c | 5 ++--- drivers/net/wireless/broadcom/brcm80211/brcmfmac/p2p.c | 1 + 3 files changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c index 2443c71a202f..63e7683a80dd 100644 --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c @@ -625,6 +625,7 @@ struct wireless_dev *brcmf_ap_add_vif(struct wiphy *wiphy, const char *name, err = brcmf_net_attach(ifp, true); if (err) { brcmf_err("Registering netdevice failed\n"); + free_netdev(ifp->ndev); goto fail; } diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c index c60b897e479a..b4c86434ad80 100644 --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c @@ -485,13 +485,13 @@ int brcmf_net_attach(struct brcmf_if *ifp, bool rtnl_locked) goto fail; } + ndev->priv_destructor = brcmf_cfg80211_free_netdev; brcmf_dbg(INFO, "%s: Broadcom Dongle Host Driver\n", ndev->name); return 0; fail: drvr->iflist[ifp->bsscfgidx] = NULL; ndev->netdev_ops = NULL; - free_netdev(ndev); return -EBADE; } @@ -504,6 +504,7 @@ static void brcmf_net_detach(struct net_device *ndev, bool rtnl_locked) unregister_netdev(ndev); } else { brcmf_cfg80211_free_netdev(ndev); + free_netdev(ndev); } } @@ -580,7 +581,6 @@ static int brcmf_net_p2p_attach(struct brcmf_if *ifp) fail: ifp->drvr->iflist[ifp->bsscfgidx] = NULL; ndev->netdev_ops = NULL; - free_netdev(ndev); return -EBADE; } @@ -626,7 +626,6 @@ struct brcmf_if *brcmf_add_if(struct brcmf_pub *drvr, s32 bsscfgidx, s32 ifidx, return ERR_PTR(-ENOMEM); ndev->needs_free_netdev = true; - ndev->priv_destructor = brcmf_cfg80211_free_netdev; ifp = netdev_priv(ndev); ifp->ndev = ndev; /* store mapping ifidx to bsscfgidx */ diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/p2p.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/p2p.c index aa299c47bfa2..2ce675ab40ef 100644 --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/p2p.c +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/p2p.c @@ -2208,6 +2208,7 @@ struct wireless_dev *brcmf_p2p_add_vif(struct wiphy *wiphy, const char *name, err = brcmf_net_attach(ifp, true); if (err) { brcmf_err("Registering netdevice failed\n"); + free_netdev(ifp->ndev); goto fail; } -- 2.20.1