4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Sara Sharon sara.sharon@intel.com
commit f631a77ba920f7153a1094d09cd8f2ebbffd0328 upstream.
Some hardware (iwlwifi an example) de-aggregate AMSDUs and copy the IV as is to the generated MPDUs, so the same PN appears in multiple packets without being a replay attack. Allow driver to explicitly indicate that a frame is allowed to have the same PN as the previous frame.
Signed-off-by: Sara Sharon sara.sharon@intel.com Signed-off-by: Luca Coelho luciano.coelho@intel.com Signed-off-by: Johannes Berg johannes.berg@intel.com Cc: Sriram R srirrama@codeaurora.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- include/net/mac80211.h | 6 +++++- net/mac80211/wpa.c | 16 ++++++++++++---- 2 files changed, 17 insertions(+), 5 deletions(-)
--- a/include/net/mac80211.h +++ b/include/net/mac80211.h @@ -1031,6 +1031,9 @@ ieee80211_tx_info_clear_status(struct ie * @RX_FLAG_RADIOTAP_VENDOR_DATA: This frame contains vendor-specific * radiotap data in the skb->data (before the frame) as described by * the &struct ieee80211_vendor_radiotap. + * @RX_FLAG_ALLOW_SAME_PN: Allow the same PN as same packet before. + * This is used for AMSDU subframes which can have the same PN as + * the first subframe. */ enum mac80211_rx_flags { RX_FLAG_MMIC_ERROR = BIT(0), @@ -1061,7 +1064,8 @@ enum mac80211_rx_flags { RX_FLAG_5MHZ = BIT(29), RX_FLAG_AMSDU_MORE = BIT(30), RX_FLAG_RADIOTAP_VENDOR_DATA = BIT(31), - RX_FLAG_MIC_STRIPPED = BIT_ULL(32), + RX_FLAG_MIC_STRIPPED = BIT_ULL(32), + RX_FLAG_ALLOW_SAME_PN = BIT_ULL(33), };
#define RX_FLAG_STBC_SHIFT 26 --- a/net/mac80211/wpa.c +++ b/net/mac80211/wpa.c @@ -523,12 +523,16 @@ ieee80211_crypto_ccmp_decrypt(struct iee return RX_DROP_UNUSABLE;
if (!(status->flag & RX_FLAG_PN_VALIDATED)) { + int res; + ccmp_hdr2pn(pn, skb->data + hdrlen);
queue = rx->security_idx;
- if (memcmp(pn, key->u.ccmp.rx_pn[queue], - IEEE80211_CCMP_PN_LEN) <= 0) { + res = memcmp(pn, key->u.ccmp.rx_pn[queue], + IEEE80211_CCMP_PN_LEN); + if (res < 0 || + (!res && !(status->flag & RX_FLAG_ALLOW_SAME_PN))) { key->u.ccmp.replays++; return RX_DROP_UNUSABLE; } @@ -749,12 +753,16 @@ ieee80211_crypto_gcmp_decrypt(struct iee return RX_DROP_UNUSABLE;
if (!(status->flag & RX_FLAG_PN_VALIDATED)) { + int res; + gcmp_hdr2pn(pn, skb->data + hdrlen);
queue = rx->security_idx;
- if (memcmp(pn, key->u.gcmp.rx_pn[queue], - IEEE80211_GCMP_PN_LEN) <= 0) { + res = memcmp(pn, key->u.gcmp.rx_pn[queue], + IEEE80211_GCMP_PN_LEN); + if (res < 0 || + (!res && !(status->flag & RX_FLAG_ALLOW_SAME_PN))) { key->u.gcmp.replays++; return RX_DROP_UNUSABLE; }