This is a note to let you know that I've just added the patch titled

nl80211: Sanitize array index in parse_txq_params

to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: nl80211-sanitize-array-index-in-parse_txq_params.patch and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.

From foo@baz Thu Feb 8 03:32:24 CET 2018

From: Dan Williams dan.j.williams@intel.com Date: Mon, 29 Jan 2018 17:03:15 -0800 Subject: nl80211: Sanitize array index in parse_txq_params

From: Dan Williams dan.j.williams@intel.com

(cherry picked from commit 259d8c1e984318497c84eef547bbb6b1d9f4eb05)

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@gmail.com Reported-by: Elena Reshetova elena.reshetova@intel.com Signed-off-by: Dan Williams dan.j.williams@intel.com Signed-off-by: Thomas Gleixner tglx@linutronix.de Acked-by: Johannes Berg johannes@sipsolutions.net Cc: linux-arch@vger.kernel.org Cc: kernel-hardening@lists.openwall.com Cc: gregkh@linuxfoundation.org Cc: linux-wireless@vger.kernel.org Cc: torvalds@linux-foundation.org Cc: "David S. Miller" davem@davemloft.net Cc: alan@linux.intel.com Link: https://lkml.kernel.org/r/151727419584.33451.7700736761686184303.stgit@dwill... Signed-off-by: David Woodhouse dwmw@amazon.co.uk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/wireless/nl80211.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-)

--- 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> @@ -2014,20 +2015,22 @@ static const struct nla_policy txq_param 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; }

Patches currently in stable-queue which might be from dan.j.williams@intel.com are

queue-4.9/kvm-vmx-allow-direct-access-to-msr_ia32_spec_ctrl.patch queue-4.9/kvm-x86-add-ibpb-support.patch queue-4.9/kvm-svm-allow-direct-access-to-msr_ia32_spec_ctrl.patch queue-4.9/x86-paravirt-remove-noreplace-paravirt-cmdline-option.patch queue-4.9/documentation-document-array_index_nospec.patch queue-4.9/x86-usercopy-replace-open-coded-stac-clac-with-__uaccess_-begin-end.patch queue-4.9/kvm-x86-make-indirect-calls-in-emulator-speculation-safe.patch queue-4.9/vfs-fdtable-prevent-bounds-check-bypass-via-speculative-execution.patch queue-4.9/x86-uaccess-use-__uaccess_begin_nospec-and-uaccess_try_nospec.patch queue-4.9/x86-implement-array_index_mask_nospec.patch queue-4.9/array_index_nospec-sanitize-speculative-array-de-references.patch queue-4.9/kvm-vmx-make-indirect-call-speculation-safe.patch queue-4.9/x86-kvm-update-spectre-v1-mitigation.patch queue-4.9/x86-get_user-use-pointer-masking-to-limit-speculation.patch queue-4.9/x86-syscall-sanitize-syscall-table-de-references-under-speculation.patch queue-4.9/x86-spectre-report-get_user-mitigation-for-spectre_v1.patch queue-4.9/x86-introduce-barrier_nospec.patch queue-4.9/kvm-vmx-emulate-msr_ia32_arch_capabilities.patch queue-4.9/x86-introduce-__uaccess_begin_nospec-and-uaccess_try_nospec.patch queue-4.9/nl80211-sanitize-array-index-in-parse_txq_params.patch