Message ID | 20231204171130.141394-1-dmantipov@yandex.ru (mailing list archive) |
---|---|
State | Accepted |
Commit | fe0a7776d4d19e613bb8dd80fe2d78ae49e8b49d |
Delegated to: | Kalle Valo |
Headers | show |
Series | [v2] wifi: wfx: fix possible NULL pointer dereference in wfx_set_mfp_ap() | expand |
On Monday 4 December 2023 18:11:28 CET Dmitry Antipov wrote: > Since 'ieee80211_beacon_get()' can return NULL, 'wfx_set_mfp_ap()' > should check the return value before examining skb data. So convert > the latter to return an appropriate error code and propagate it to > return from 'wfx_start_ap()' as well. Compile tested only. > > Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru> > --- > v2: adjust branches according to maintainer's suggestions > --- > drivers/net/wireless/silabs/wfx/sta.c | 42 ++++++++++++++++----------- > 1 file changed, 25 insertions(+), 17 deletions(-) > > diff --git a/drivers/net/wireless/silabs/wfx/sta.c b/drivers/net/wireless/silabs/wfx/sta.c > index 1b6c158457b4..537caf9d914a 100644 > --- a/drivers/net/wireless/silabs/wfx/sta.c > +++ b/drivers/net/wireless/silabs/wfx/sta.c > @@ -336,29 +336,38 @@ static int wfx_upload_ap_templates(struct wfx_vif *wvif) > return 0; > } > > -static void wfx_set_mfp_ap(struct wfx_vif *wvif) > +static int wfx_set_mfp_ap(struct wfx_vif *wvif) > { > struct ieee80211_vif *vif = wvif_to_vif(wvif); > struct sk_buff *skb = ieee80211_beacon_get(wvif->wdev->hw, vif, 0); > const int ieoffset = offsetof(struct ieee80211_mgmt, u.beacon.variable); > - const u16 *ptr = (u16 *)cfg80211_find_ie(WLAN_EID_RSN, skb->data + ieoffset, > - skb->len - ieoffset); > const int pairwise_cipher_suite_count_offset = 8 / sizeof(u16); > const int pairwise_cipher_suite_size = 4 / sizeof(u16); > const int akm_suite_size = 4 / sizeof(u16); > + const u16 *ptr; > > - if (ptr) { > - ptr += pairwise_cipher_suite_count_offset; > - if (WARN_ON(ptr > (u16 *)skb_tail_pointer(skb))) > - return; > - ptr += 1 + pairwise_cipher_suite_size * *ptr; > - if (WARN_ON(ptr > (u16 *)skb_tail_pointer(skb))) > - return; > - ptr += 1 + akm_suite_size * *ptr; > - if (WARN_ON(ptr > (u16 *)skb_tail_pointer(skb))) > - return; > - wfx_hif_set_mfp(wvif, *ptr & BIT(7), *ptr & BIT(6)); > - } > + if (unlikely(!skb)) > + return -ENOMEM; > + > + ptr = (u16 *)cfg80211_find_ie(WLAN_EID_RSN, skb->data + ieoffset, > + skb->len - ieoffset); > + if (unlikely(!ptr)) > + return -EINVAL; > + > + ptr += pairwise_cipher_suite_count_offset; > + if (WARN_ON(ptr > (u16 *)skb_tail_pointer(skb))) > + return -EINVAL; > + > + ptr += 1 + pairwise_cipher_suite_size * *ptr; > + if (WARN_ON(ptr > (u16 *)skb_tail_pointer(skb))) > + return -EINVAL; > + > + ptr += 1 + akm_suite_size * *ptr; > + if (WARN_ON(ptr > (u16 *)skb_tail_pointer(skb))) > + return -EINVAL; > + > + wfx_hif_set_mfp(wvif, *ptr & BIT(7), *ptr & BIT(6)); > + return 0; > } > > int wfx_start_ap(struct ieee80211_hw *hw, struct ieee80211_vif *vif, > @@ -376,8 +385,7 @@ int wfx_start_ap(struct ieee80211_hw *hw, struct ieee80211_vif *vif, > ret = wfx_hif_start(wvif, &vif->bss_conf, wvif->channel); > if (ret > 0) > return -EIO; > - wfx_set_mfp_ap(wvif); > - return ret; > + return wfx_set_mfp_ap(wvif); > } > > void wfx_stop_ap(struct ieee80211_hw *hw, struct ieee80211_vif *vif, > -- > 2.43.0 > > Tested-by: Jérôme Pouiller <jerome.pouiller@silabs.com> Acked-by: Jérôme Pouiller <jerome.pouiller@silabs.com> For the record, I tested with hostapd and this configuration: channel=1 ctrl_interface=/var/run/hostapd driver=nl80211 ht_capab=[SHORT-GI-20] hw_mode=g ieee80211n=1 ieee80211w=2 interface=wlan0 rsn_pairwise=CCMP ssid=rpi-jpo-slv1 wpa=2 wpa_key_mgmt=WPA-PSK wpa_passphrase=password
Dmitry Antipov <dmantipov@yandex.ru> wrote: > Since 'ieee80211_beacon_get()' can return NULL, 'wfx_set_mfp_ap()' > should check the return value before examining skb data. So convert > the latter to return an appropriate error code and propagate it to > return from 'wfx_start_ap()' as well. Compile tested only. > > Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru> > Tested-by: Jérôme Pouiller <jerome.pouiller@silabs.com> > Acked-by: Jérôme Pouiller <jerome.pouiller@silabs.com> Patch applied to wireless-next.git, thanks. fe0a7776d4d1 wifi: wfx: fix possible NULL pointer dereference in wfx_set_mfp_ap()
diff --git a/drivers/net/wireless/silabs/wfx/sta.c b/drivers/net/wireless/silabs/wfx/sta.c index 1b6c158457b4..537caf9d914a 100644 --- a/drivers/net/wireless/silabs/wfx/sta.c +++ b/drivers/net/wireless/silabs/wfx/sta.c @@ -336,29 +336,38 @@ static int wfx_upload_ap_templates(struct wfx_vif *wvif) return 0; } -static void wfx_set_mfp_ap(struct wfx_vif *wvif) +static int wfx_set_mfp_ap(struct wfx_vif *wvif) { struct ieee80211_vif *vif = wvif_to_vif(wvif); struct sk_buff *skb = ieee80211_beacon_get(wvif->wdev->hw, vif, 0); const int ieoffset = offsetof(struct ieee80211_mgmt, u.beacon.variable); - const u16 *ptr = (u16 *)cfg80211_find_ie(WLAN_EID_RSN, skb->data + ieoffset, - skb->len - ieoffset); const int pairwise_cipher_suite_count_offset = 8 / sizeof(u16); const int pairwise_cipher_suite_size = 4 / sizeof(u16); const int akm_suite_size = 4 / sizeof(u16); + const u16 *ptr; - if (ptr) { - ptr += pairwise_cipher_suite_count_offset; - if (WARN_ON(ptr > (u16 *)skb_tail_pointer(skb))) - return; - ptr += 1 + pairwise_cipher_suite_size * *ptr; - if (WARN_ON(ptr > (u16 *)skb_tail_pointer(skb))) - return; - ptr += 1 + akm_suite_size * *ptr; - if (WARN_ON(ptr > (u16 *)skb_tail_pointer(skb))) - return; - wfx_hif_set_mfp(wvif, *ptr & BIT(7), *ptr & BIT(6)); - } + if (unlikely(!skb)) + return -ENOMEM; + + ptr = (u16 *)cfg80211_find_ie(WLAN_EID_RSN, skb->data + ieoffset, + skb->len - ieoffset); + if (unlikely(!ptr)) + return -EINVAL; + + ptr += pairwise_cipher_suite_count_offset; + if (WARN_ON(ptr > (u16 *)skb_tail_pointer(skb))) + return -EINVAL; + + ptr += 1 + pairwise_cipher_suite_size * *ptr; + if (WARN_ON(ptr > (u16 *)skb_tail_pointer(skb))) + return -EINVAL; + + ptr += 1 + akm_suite_size * *ptr; + if (WARN_ON(ptr > (u16 *)skb_tail_pointer(skb))) + return -EINVAL; + + wfx_hif_set_mfp(wvif, *ptr & BIT(7), *ptr & BIT(6)); + return 0; } int wfx_start_ap(struct ieee80211_hw *hw, struct ieee80211_vif *vif, @@ -376,8 +385,7 @@ int wfx_start_ap(struct ieee80211_hw *hw, struct ieee80211_vif *vif, ret = wfx_hif_start(wvif, &vif->bss_conf, wvif->channel); if (ret > 0) return -EIO; - wfx_set_mfp_ap(wvif); - return ret; + return wfx_set_mfp_ap(wvif); } void wfx_stop_ap(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
Since 'ieee80211_beacon_get()' can return NULL, 'wfx_set_mfp_ap()' should check the return value before examining skb data. So convert the latter to return an appropriate error code and propagate it to return from 'wfx_start_ap()' as well. Compile tested only. Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru> --- v2: adjust branches according to maintainer's suggestions --- drivers/net/wireless/silabs/wfx/sta.c | 42 ++++++++++++++++----------- 1 file changed, 25 insertions(+), 17 deletions(-)