|
Message-ID: <151727419584.33451.7700736761686184303.stgit@dwillia2-desk3.amr.corp.intel.com> Date: Mon, 29 Jan 2018 17:03:15 -0800 From: Dan Williams <dan.j.williams@...el.com> To: tglx@...utronix.de, mingo@...nel.org Cc: linux-arch@...r.kernel.org, Christian Lamparter <chunkeey@...il.com>, gregkh@...uxfoundation.org, kernel-hardening@...ts.openwall.com, linux-wireless@...r.kernel.org, linux-kernel@...r.kernel.org, Johannes Berg <johannes@...solutions.net>, torvalds@...ux-foundation.org, "David S. Miller" <davem@...emloft.net>, Elena Reshetova <elena.reshetova@...el.com>, alan@...ux.intel.com Subject: [PATCH v6 12/13] nl80211: sanitize array index in parse_txq_params Wireless drivers rely on parse_txq_params to validate that txq_params->ac is less than NL80211_NUM_ACS by the time the low-level driver's ->conf_tx() handler is called. Use a new helper, array_index_nospec(), to sanitize txq_params->ac with respect to speculation. I.e. ensure that any speculation into ->conf_tx() handlers is done with a value of txq_params->ac that is within the bounds of [0, NL80211_NUM_ACS). Reported-by: Christian Lamparter <chunkeey@...il.com> Reported-by: Elena Reshetova <elena.reshetova@...el.com> Acked-by: Johannes Berg <johannes@...solutions.net> Cc: "David S. Miller" <davem@...emloft.net> Cc: linux-wireless@...r.kernel.org Signed-off-by: Dan Williams <dan.j.williams@...el.com> --- net/wireless/nl80211.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index d396cb61a280..81bef0676e1d 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -16,6 +16,7 @@ #include <linux/nl80211.h> #include <linux/rtnetlink.h> #include <linux/netlink.h> +#include <linux/nospec.h> #include <linux/etherdevice.h> #include <net/net_namespace.h> #include <net/genetlink.h> @@ -2056,20 +2057,22 @@ static const struct nla_policy txq_params_policy[NL80211_TXQ_ATTR_MAX + 1] = { static int parse_txq_params(struct nlattr *tb[], struct ieee80211_txq_params *txq_params) { + u8 ac; + if (!tb[NL80211_TXQ_ATTR_AC] || !tb[NL80211_TXQ_ATTR_TXOP] || !tb[NL80211_TXQ_ATTR_CWMIN] || !tb[NL80211_TXQ_ATTR_CWMAX] || !tb[NL80211_TXQ_ATTR_AIFS]) return -EINVAL; - txq_params->ac = nla_get_u8(tb[NL80211_TXQ_ATTR_AC]); + ac = nla_get_u8(tb[NL80211_TXQ_ATTR_AC]); txq_params->txop = nla_get_u16(tb[NL80211_TXQ_ATTR_TXOP]); txq_params->cwmin = nla_get_u16(tb[NL80211_TXQ_ATTR_CWMIN]); txq_params->cwmax = nla_get_u16(tb[NL80211_TXQ_ATTR_CWMAX]); txq_params->aifs = nla_get_u8(tb[NL80211_TXQ_ATTR_AIFS]); - if (txq_params->ac >= NL80211_NUM_ACS) + if (ac >= NL80211_NUM_ACS) return -EINVAL; - + txq_params->ac = array_index_nospec(ac, NL80211_NUM_ACS); return 0; }
Powered by blists - more mailing lists
Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.