RE: [PATCH] mwifiex: printk() overflow with 32-byte SSIDs

From: Amitkumar Karwar
Date: Wed Nov 09 2016 - 02:51:41 EST


> From: Brian Norris [mailto:briannorris@xxxxxxxxxxxx]
> Sent: Wednesday, November 09, 2016 7:58 AM
> To: Amitkumar Karwar; Nishant Sarmukadam; Kalle Valo
> Cc: linux-kernel@xxxxxxxxxxxxxxx; linux-wireless@xxxxxxxxxxxxxxx; Cathy
> Luo; security@xxxxxxxxxx; stable@xxxxxxxxxxxxxxx; Brian Norris
> Subject: [PATCH] mwifiex: printk() overflow with 32-byte SSIDs
>
> SSIDs aren't guaranteed to be 0-terminated. Let's cap the max length
> when we print them out.
>
> This can be easily noticed by connecting to a network with a 32-octet
> SSID:
>
> [ 3903.502925] mwifiex_pcie 0000:01:00.0: info: trying to associate to
> '0123456789abcdef0123456789abcdef <uninitialized mem>' bssid
> xx:xx:xx:xx:xx:xx
>
> Fixes: 5e6e3a92b9a4 ("wireless: mwifiex: initial commit for Marvell
> mwifiex driver")
> Signed-off-by: Brian Norris <briannorris@xxxxxxxxxxxx>
> Cc: <stable@xxxxxxxxxxxxxxx>
> ---
> drivers/net/wireless/marvell/mwifiex/cfg80211.c | 13 +++++++------
> 1 file changed, 7 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/net/wireless/marvell/mwifiex/cfg80211.c
> b/drivers/net/wireless/marvell/mwifiex/cfg80211.c
> index 39ce76ad00bc..16241d21727b 100644
> --- a/drivers/net/wireless/marvell/mwifiex/cfg80211.c
> +++ b/drivers/net/wireless/marvell/mwifiex/cfg80211.c
> @@ -2222,8 +2222,9 @@ mwifiex_cfg80211_assoc(struct mwifiex_private
> *priv, size_t ssid_len,
> is_scanning_required = 1;
> } else {
> mwifiex_dbg(priv->adapter, MSG,
> - "info: trying to associate to '%s' bssid
> %pM\n",
> - (char *)req_ssid.ssid, bss->bssid);
> + "info: trying to associate to '%.*s' bssid
> %pM\n",
> + req_ssid.ssid_len, (char *)req_ssid.ssid,
> + bss->bssid);
> memcpy(&priv->cfg_bssid, bss->bssid, ETH_ALEN);
> break;
> }
> @@ -2283,8 +2284,8 @@ mwifiex_cfg80211_connect(struct wiphy *wiphy,
> struct net_device *dev,
> }
>
> mwifiex_dbg(adapter, INFO,
> - "info: Trying to associate to %s and bssid %pM\n",
> - (char *)sme->ssid, sme->bssid);
> + "info: Trying to associate to %.*s and bssid %pM\n",
> + (int)sme->ssid_len, (char *)sme->ssid, sme->bssid);
>
> if (!mwifiex_stop_bg_scan(priv))
> cfg80211_sched_scan_stopped_rtnl(priv->wdev.wiphy);
> @@ -2417,8 +2418,8 @@ mwifiex_cfg80211_join_ibss(struct wiphy *wiphy,
> struct net_device *dev,
> }
>
> mwifiex_dbg(priv->adapter, MSG,
> - "info: trying to join to %s and bssid %pM\n",
> - (char *)params->ssid, params->bssid);
> + "info: trying to join to %.*s and bssid %pM\n",
> + params->ssid_len, (char *)params->ssid, params->bssid);
>
> mwifiex_set_ibss_params(priv, params);
>
> --
> 2.8.0.rc3.226.g39d4020

Thanks for fixing this.

Acked-by: Amitkumar Karwar <akarwar@xxxxxxxxxxx>

Regards,
Amitkumar