FIX: [mac80211] assure all fragments are encrypted (CVE-2020-26147)

FIX: [mac80211] prevent mixed key and fragment cache attacks (CVE-2020-24586, CVE-2020-24587)
    FIX: [mac80211] properly handle A-MSDUs that start with an RFC 1042 header
    FIX: [mac80211] Mitigate A-MSDU injection attacks (CVE-2020-24588)
    FIX: [mac80211] drop A-MSDUs completely with old ciphers. (CVE-2020-24588)
    FIX: [mac80211] add fragment cache to sta_info
    FIX: [mac80211] check defrag PN against current frame
    FIX: [mac80211] prevent attacks on TKIP/WEP as well
    FIX: [mac80211] do not accept/forward invalid EAPOL frames
    FIX: [mac80211] extend protection against mixed key and fragment cache attacks (CVE-2020-24586, CVE-2020-24587)
    FIX: [mac80211] ath10k: add CCMP PN replay protection for fragmented frames for PCIe
    FIX: [mac80211] ath10k: drop fragments with multicast DA for PCIe (CVE-2020-26145)
    FIX: [mac80211] ath10k: drop fragments with multicast DA for SDIO (CVE-2020-26145)
    FIX: [mac80211] ath10k: drop MPDU which has discard flag set by firmware for SDIO (CVE-2020-24588)
    FIX: [mac80211] ath10k: Fix TKIP Michael MIC verification for PCIe (CVE-2020-26141)
    FIX: [mac80211] ath10k: Validate first subframe of A-MSDU before processing the list
    FIX: [wl18xx] firmware: updated to version 8.9.0.0.88 (Fixes related to Wi-Fi FragAttacks - FRagmentation and AGgregation Attacks)

    BugzId: 72727
    (cherry picked from commit 4fb2e1d93b)
This commit is contained in:
Patrick Walther 2021-05-13 13:03:04 +02:00
parent 412dfbc9af
commit 8f746d1044
4 changed files with 955 additions and 2 deletions

View File

@ -12,7 +12,7 @@ SRC_URI += " \
file://nm-wl18xx-TIInit_11.8.32.bts \
"
SRCREV = "5ec05007f2662f460f881c5868311fd3ab7e6e71"
SRCREV = "bda5304cc86e9c4029f8101394d2a8b39c640f53"
S = "${WORKDIR}/git"

View File

@ -0,0 +1,952 @@
diff --git a/drivers/net/wireless/ath/ath10k/htt.h b/drivers/net/wireless/ath/ath10k/htt.h
index 9c8ad11..a7dd616 100644
--- a/drivers/net/wireless/ath/ath10k/htt.h
+++ b/drivers/net/wireless/ath/ath10k/htt.h
@@ -836,6 +836,7 @@ enum htt_security_types {
#define ATH10K_HTT_TXRX_PEER_SECURITY_MAX 2
#define ATH10K_TXRX_NUM_EXT_TIDS 19
+#define ATH10K_TXRX_NON_QOS_TID 16
enum htt_security_flags {
#define HTT_SECURITY_TYPE_MASK 0x7F
diff --git a/drivers/net/wireless/ath/ath10k/htt_rx.c b/drivers/net/wireless/ath/ath10k/htt_rx.c
index 9f0e7b4..9e04bc4 100644
--- a/drivers/net/wireless/ath/ath10k/htt_rx.c
+++ b/drivers/net/wireless/ath/ath10k/htt_rx.c
@@ -1725,16 +1725,97 @@ static void ath10k_htt_rx_h_csum_offload(struct sk_buff *msdu)
msdu->ip_summed = ath10k_htt_rx_get_csum_state(msdu);
}
+static u64 ath10k_htt_rx_h_get_pn(struct ath10k *ar, struct sk_buff *skb,
+ u16 offset,
+ enum htt_rx_mpdu_encrypt_type enctype)
+{
+ struct ieee80211_hdr *hdr;
+ u64 pn = 0;
+ u8 *ehdr;
+
+ hdr = (struct ieee80211_hdr *)(skb->data + offset);
+ ehdr = skb->data + offset + ieee80211_hdrlen(hdr->frame_control);
+
+ if (enctype == HTT_RX_MPDU_ENCRYPT_AES_CCM_WPA2) {
+ pn = ehdr[0];
+ pn |= (u64)ehdr[1] << 8;
+ pn |= (u64)ehdr[4] << 16;
+ pn |= (u64)ehdr[5] << 24;
+ pn |= (u64)ehdr[6] << 32;
+ pn |= (u64)ehdr[7] << 40;
+ }
+ return pn;
+}
+
+static bool ath10k_htt_rx_h_frag_multicast_check(struct ath10k *ar,
+ struct sk_buff *skb,
+ u16 offset)
+{
+ struct ieee80211_hdr *hdr;
+
+ hdr = (struct ieee80211_hdr *)(skb->data + offset);
+ return !is_multicast_ether_addr(hdr->addr1);
+}
+
+static bool ath10k_htt_rx_h_frag_pn_check(struct ath10k *ar,
+ struct sk_buff *skb,
+ u16 peer_id,
+ u16 offset,
+ enum htt_rx_mpdu_encrypt_type enctype)
+{
+ struct ath10k_peer *peer;
+ union htt_rx_pn_t *last_pn, new_pn = {0};
+ struct ieee80211_hdr *hdr;
+ bool more_frags;
+ u8 tid, frag_number;
+ u32 seq;
+
+ peer = ath10k_peer_find_by_id(ar, peer_id);
+ if (!peer) {
+ ath10k_dbg(ar, ATH10K_DBG_HTT, "invalid peer for frag pn check\n");
+ return false;
+ }
+
+ hdr = (struct ieee80211_hdr *)(skb->data + offset);
+ if (ieee80211_is_data_qos(hdr->frame_control))
+ tid = ieee80211_get_tid(hdr);
+ else
+ tid = ATH10K_TXRX_NON_QOS_TID;
+
+ last_pn = &peer->frag_tids_last_pn[tid];
+ new_pn.pn48 = ath10k_htt_rx_h_get_pn(ar, skb, offset, enctype);
+ more_frags = ieee80211_has_morefrags(hdr->frame_control);
+ frag_number = le16_to_cpu(hdr->seq_ctrl) & IEEE80211_SCTL_FRAG;
+ seq = (__le16_to_cpu(hdr->seq_ctrl) & IEEE80211_SCTL_SEQ) >> 4;
+
+ if (frag_number == 0) {
+ last_pn->pn48 = new_pn.pn48;
+ peer->frag_tids_seq[tid] = seq;
+ } else {
+ if (seq != peer->frag_tids_seq[tid])
+ return false;
+
+ if (new_pn.pn48 != last_pn->pn48 + 1)
+ return false;
+
+ last_pn->pn48 = new_pn.pn48;
+ }
+
+ return true;
+}
+
static void ath10k_htt_rx_h_mpdu(struct ath10k *ar,
struct sk_buff_head *amsdu,
struct ieee80211_rx_status *status,
bool fill_crypt_header,
u8 *rx_hdr,
- enum ath10k_pkt_rx_err *err)
+ enum ath10k_pkt_rx_err *err,
+ u16 peer_id,
+ bool frag)
{
struct sk_buff *first;
struct sk_buff *last;
- struct sk_buff *msdu;
+ struct sk_buff *msdu, *temp;
struct htt_rx_desc *rxd;
struct ieee80211_hdr *hdr;
enum htt_rx_mpdu_encrypt_type enctype;
@@ -1747,6 +1828,7 @@ static void ath10k_htt_rx_h_mpdu(struct ath10k *ar,
bool is_decrypted;
bool is_mgmt;
u32 attention;
+ bool frag_pn_check = true, multicast_check = true;
if (skb_queue_empty(amsdu))
return;
@@ -1845,7 +1927,37 @@ static void ath10k_htt_rx_h_mpdu(struct ath10k *ar,
}
skb_queue_walk(amsdu, msdu) {
+ if (frag && !fill_crypt_header && is_decrypted &&
+ enctype == HTT_RX_MPDU_ENCRYPT_AES_CCM_WPA2)
+ frag_pn_check = ath10k_htt_rx_h_frag_pn_check(ar,
+ msdu,
+ peer_id,
+ 0,
+ enctype);
+
+ if (frag)
+ multicast_check = ath10k_htt_rx_h_frag_multicast_check(ar,
+ msdu,
+ 0);
+
+ if (!frag_pn_check || !multicast_check) {
+ /* Discard the fragment with invalid PN or multicast DA
+ */
+ temp = msdu->prev;
+ __skb_unlink(msdu, amsdu);
+ dev_kfree_skb_any(msdu);
+ msdu = temp;
+ frag_pn_check = true;
+ multicast_check = true;
+ continue;
+ }
+
ath10k_htt_rx_h_csum_offload(msdu);
+
+ if (frag && !fill_crypt_header &&
+ enctype == HTT_RX_MPDU_ENCRYPT_TKIP_WPA)
+ status->flag &= ~RX_FLAG_MMIC_STRIPPED;
+
ath10k_htt_rx_h_undecap(ar, msdu, status, first_hdr, enctype,
is_decrypted);
@@ -1863,6 +1975,11 @@ static void ath10k_htt_rx_h_mpdu(struct ath10k *ar,
hdr = (void *)msdu->data;
hdr->frame_control &= ~__cpu_to_le16(IEEE80211_FCTL_PROTECTED);
+
+ if (frag && !fill_crypt_header &&
+ enctype == HTT_RX_MPDU_ENCRYPT_TKIP_WPA)
+ status->flag &= ~RX_FLAG_IV_STRIPPED &
+ ~RX_FLAG_MMIC_STRIPPED;
}
}
@@ -1970,14 +2087,62 @@ static void ath10k_htt_rx_h_unchain(struct ath10k *ar,
ath10k_unchain_msdu(amsdu, unchain_cnt);
}
+static bool ath10k_htt_rx_validate_amsdu(struct ath10k *ar,
+ struct sk_buff_head *amsdu)
+{
+ u8 *subframe_hdr;
+ struct sk_buff *first;
+ bool is_first, is_last;
+ struct htt_rx_desc *rxd;
+ struct ieee80211_hdr *hdr;
+ size_t hdr_len, crypto_len;
+ enum htt_rx_mpdu_encrypt_type enctype;
+ int bytes_aligned = ar->hw_params.decap_align_bytes;
+
+ first = skb_peek(amsdu);
+
+ rxd = (void *)first->data - sizeof(*rxd);
+ hdr = (void *)rxd->rx_hdr_status;
+
+ is_first = !!(rxd->msdu_end.common.info0 &
+ __cpu_to_le32(RX_MSDU_END_INFO0_FIRST_MSDU));
+ is_last = !!(rxd->msdu_end.common.info0 &
+ __cpu_to_le32(RX_MSDU_END_INFO0_LAST_MSDU));
+
+ /* Return in case of non-aggregated msdu */
+ if (is_first && is_last)
+ return true;
+
+ /* First msdu flag is not set for the first msdu of the list */
+ if (!is_first)
+ return false;
+
+ enctype = MS(__le32_to_cpu(rxd->mpdu_start.info0),
+ RX_MPDU_START_INFO0_ENCRYPT_TYPE);
+
+ hdr_len = ieee80211_hdrlen(hdr->frame_control);
+ crypto_len = ath10k_htt_rx_crypto_param_len(ar, enctype);
+
+ subframe_hdr = (u8 *)hdr + round_up(hdr_len, bytes_aligned) +
+ crypto_len;
+
+ /* Validate if the amsdu has a proper first subframe.
+ * There are chances a single msdu can be received as amsdu when
+ * the unauthenticated amsdu flag of a QoS header
+ * gets flipped in non-SPP AMSDU's, in such cases the first
+ * subframe has llc/snap header in place of a valid da.
+ * return false if the da matches rfc1042 pattern
+ */
+ if (ether_addr_equal(subframe_hdr, rfc1042_header))
+ return false;
+
+ return true;
+}
+
static bool ath10k_htt_rx_amsdu_allowed(struct ath10k *ar,
struct sk_buff_head *amsdu,
struct ieee80211_rx_status *rx_status)
{
- /* FIXME: It might be a good idea to do some fuzzy-testing to drop
- * invalid/dangerous frames.
- */
-
if (!rx_status->freq) {
ath10k_dbg(ar, ATH10K_DBG_HTT, "no channel configured; ignoring frame(s)!\n");
return false;
@@ -1988,6 +2153,11 @@ static bool ath10k_htt_rx_amsdu_allowed(struct ath10k *ar,
return false;
}
+ if (!ath10k_htt_rx_validate_amsdu(ar, amsdu)) {
+ ath10k_dbg(ar, ATH10K_DBG_HTT, "invalid amsdu received\n");
+ return false;
+ }
+
return true;
}
@@ -2050,7 +2220,8 @@ static int ath10k_htt_rx_handle_amsdu(struct ath10k_htt *htt)
ath10k_htt_rx_h_unchain(ar, &amsdu, &drop_cnt, &unchain_cnt);
ath10k_htt_rx_h_filter(ar, &amsdu, rx_status, &drop_cnt_filter);
- ath10k_htt_rx_h_mpdu(ar, &amsdu, rx_status, true, first_hdr, &err);
+ ath10k_htt_rx_h_mpdu(ar, &amsdu, rx_status, true, first_hdr, &err, 0,
+ false);
msdus_to_queue = skb_queue_len(&amsdu);
ath10k_htt_rx_h_enqueue(ar, &amsdu, rx_status);
@@ -2183,6 +2354,11 @@ static bool ath10k_htt_rx_proc_rx_ind_hl(struct ath10k_htt *htt,
fw_desc = &rx->fw_desc;
rx_desc_len = fw_desc->len;
+ if (fw_desc->u.bits.discard) {
+ ath10k_dbg(ar, ATH10K_DBG_HTT, "htt discard mpdu\n");
+ goto err;
+ }
+
/* I have not yet seen any case where num_mpdu_ranges > 1.
* qcacld does not seem handle that case either, so we introduce the
* same limitiation here as well.
@@ -2483,6 +2659,13 @@ static bool ath10k_htt_rx_proc_rx_frag_ind_hl(struct ath10k_htt *htt,
rx_desc = (struct htt_hl_rx_desc *)(skb->data + tot_hdr_len);
rx_desc_info = __le32_to_cpu(rx_desc->info);
+ hdr = (struct ieee80211_hdr *)((u8 *)rx_desc + rx_hl->fw_desc.len);
+
+ if (is_multicast_ether_addr(hdr->addr1)) {
+ /* Discard the fragment with multicast DA */
+ goto err;
+ }
+
if (!MS(rx_desc_info, HTT_RX_DESC_HL_INFO_ENCRYPTED)) {
spin_unlock_bh(&ar->data_lock);
return ath10k_htt_rx_proc_rx_ind_hl(htt, &resp->rx_ind_hl, skb,
@@ -2490,8 +2673,6 @@ static bool ath10k_htt_rx_proc_rx_frag_ind_hl(struct ath10k_htt *htt,
HTT_RX_NON_TKIP_MIC);
}
- hdr = (struct ieee80211_hdr *)((u8 *)rx_desc + rx_hl->fw_desc.len);
-
if (ieee80211_has_retry(hdr->frame_control))
goto err;
@@ -3000,7 +3181,7 @@ static int ath10k_htt_rx_in_ord_ind(struct ath10k *ar, struct sk_buff *skb)
ath10k_htt_rx_h_ppdu(ar, &amsdu, status, vdev_id);
ath10k_htt_rx_h_filter(ar, &amsdu, status, NULL);
ath10k_htt_rx_h_mpdu(ar, &amsdu, status, false, NULL,
- NULL);
+ NULL, peer_id, frag);
ath10k_htt_rx_h_enqueue(ar, &amsdu, status);
break;
case -EAGAIN:
diff --git a/drivers/net/wireless/ath/ath10k/rx_desc.h b/drivers/net/wireless/ath/ath10k/rx_desc.h
index dec1582..13a1cae 100644
--- a/drivers/net/wireless/ath/ath10k/rx_desc.h
+++ b/drivers/net/wireless/ath/ath10k/rx_desc.h
@@ -1282,7 +1282,19 @@ struct fw_rx_desc_base {
#define FW_RX_DESC_UDP (1 << 6)
struct fw_rx_desc_hl {
- u8 info0;
+ union {
+ struct {
+ u8 discard:1,
+ forward:1,
+ any_err:1,
+ dup_err:1,
+ reserved:1,
+ inspect:1,
+ extension:2;
+ } bits;
+ u8 info0;
+ } u;
+
u8 version;
u8 len;
u8 flags;
diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 8099b10..75ecfeb 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -5207,7 +5207,7 @@ unsigned int ieee80211_get_mesh_hdrlen(struct ieee80211s_hdr *meshhdr);
*/
int ieee80211_data_to_8023_exthdr(struct sk_buff *skb, struct ethhdr *ehdr,
const u8 *addr, enum nl80211_iftype iftype,
- u8 data_offset);
+ u8 data_offset, bool is_amsdu);
/**
* ieee80211_data_to_8023 - convert an 802.11 data frame to 802.3
@@ -5219,7 +5219,7 @@ int ieee80211_data_to_8023_exthdr(struct sk_buff *skb, struct ethhdr *ehdr,
static inline int ieee80211_data_to_8023(struct sk_buff *skb, const u8 *addr,
enum nl80211_iftype iftype)
{
- return ieee80211_data_to_8023_exthdr(skb, NULL, addr, iftype, 0);
+ return ieee80211_data_to_8023_exthdr(skb, NULL, addr, iftype, 0, false);
}
/**
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index f75fb7d..60cd5b0 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -50,12 +50,6 @@ struct ieee80211_local;
#define IEEE80211_ENCRYPT_HEADROOM 8
#define IEEE80211_ENCRYPT_TAILROOM 18
-/* IEEE 802.11 (Ch. 9.5 Defragmentation) requires support for concurrent
- * reception of at least three fragmented frames. This limit can be increased
- * by changing this define, at the cost of slower frame reassembly and
- * increased memory use (about 2 kB of RAM per entry). */
-#define IEEE80211_FRAGMENT_MAX 4
-
/* power level hasn't been configured (or set to automatic) */
#define IEEE80211_UNSET_POWER_LEVEL INT_MIN
@@ -88,18 +82,6 @@ extern const u8 ieee80211_ac_to_qos_mask[IEEE80211_NUM_ACS];
#define IEEE80211_MAX_NAN_INSTANCE_ID 255
-struct ieee80211_fragment_entry {
- struct sk_buff_head skb_list;
- unsigned long first_frag_time;
- u16 seq;
- u16 extra_len;
- u16 last_frag;
- u8 rx_queue;
- bool check_sequential_pn; /* needed for CCMP/GCMP */
- u8 last_pn[6]; /* PN of the last fragment if CCMP was used */
-};
-
-
struct ieee80211_bss {
u32 device_ts_beacon, device_ts_presp;
@@ -240,8 +222,15 @@ struct ieee80211_rx_data {
*/
int security_idx;
- u32 tkip_iv32;
- u16 tkip_iv16;
+ union {
+ struct {
+ u32 iv32;
+ u16 iv16;
+ } tkip;
+ struct {
+ u8 pn[IEEE80211_CCMP_PN_LEN];
+ } ccm_gcm;
+ };
};
struct ieee80211_csa_settings {
@@ -894,9 +883,7 @@ struct ieee80211_sub_if_data {
char name[IFNAMSIZ];
- /* Fragment table for host-based reassembly */
- struct ieee80211_fragment_entry fragments[IEEE80211_FRAGMENT_MAX];
- unsigned int fragment_next;
+ struct ieee80211_fragment_cache frags;
/* TID bitmap for NoAck policy */
u16 noack_map;
@@ -2268,4 +2255,7 @@ u32 ieee80211_calc_expected_tx_airtime(struct ieee80211_hw *hw,
#define debug_noinline
#endif
+void ieee80211_init_frag_cache(struct ieee80211_fragment_cache *cache);
+void ieee80211_destroy_frag_cache(struct ieee80211_fragment_cache *cache);
+
#endif /* IEEE80211_I_H */
diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c
index 1c6bb17..a88795c 100644
--- a/net/mac80211/iface.c
+++ b/net/mac80211/iface.c
@@ -1108,16 +1108,12 @@ static void ieee80211_set_multicast_list(struct net_device *dev)
*/
static void ieee80211_teardown_sdata(struct ieee80211_sub_if_data *sdata)
{
- int i;
-
/* free extra data */
ieee80211_free_keys(sdata, false);
ieee80211_debugfs_remove_netdev(sdata);
- for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++)
- __skb_queue_purge(&sdata->fragments[i].skb_list);
- sdata->fragment_next = 0;
+ ieee80211_destroy_frag_cache(&sdata->frags);
if (ieee80211_vif_is_mesh(&sdata->vif))
ieee80211_mesh_teardown_sdata(sdata);
@@ -1893,8 +1889,7 @@ int ieee80211_if_add(struct ieee80211_local *local, const char *name,
sdata->wdev.wiphy = local->hw.wiphy;
sdata->local = local;
- for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++)
- skb_queue_head_init(&sdata->fragments[i].skb_list);
+ ieee80211_init_frag_cache(&sdata->frags);
INIT_LIST_HEAD(&sdata->key_list);
diff --git a/net/mac80211/key.c b/net/mac80211/key.c
index efc1acc..fff7efc 100644
--- a/net/mac80211/key.c
+++ b/net/mac80211/key.c
@@ -764,6 +764,7 @@ int ieee80211_key_link(struct ieee80211_key *key,
struct ieee80211_sub_if_data *sdata,
struct sta_info *sta)
{
+ static atomic_t key_color = ATOMIC_INIT(0);
struct ieee80211_key *old_key;
int idx = key->conf.keyidx;
bool pairwise = key->conf.flags & IEEE80211_KEY_FLAG_PAIRWISE;
@@ -815,6 +816,12 @@ int ieee80211_key_link(struct ieee80211_key *key,
key->sdata = sdata;
key->sta = sta;
+ /*
+ * Assign a unique ID to every key so we can easily prevent mixed
+ * key and fragment cache attacks.
+ */
+ key->color = atomic_inc_return(&key_color);
+
increment_tailroom_need_count(sdata);
ret = ieee80211_key_replace(sdata, sta, pairwise, old_key, key);
diff --git a/net/mac80211/key.h b/net/mac80211/key.h
index cbc219d..39a50ba 100644
--- a/net/mac80211/key.h
+++ b/net/mac80211/key.h
@@ -127,6 +127,8 @@ struct ieee80211_key {
} debugfs;
#endif
+ unsigned int color;
+
/*
* key config, must be last because it contains key
* material as variable length member
diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index cd3e241..77463a8 100644
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -2084,19 +2084,34 @@ ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx)
return result;
}
+void ieee80211_init_frag_cache(struct ieee80211_fragment_cache *cache)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(cache->entries); i++)
+ skb_queue_head_init(&cache->entries[i].skb_list);
+}
+
+void ieee80211_destroy_frag_cache(struct ieee80211_fragment_cache *cache)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(cache->entries); i++)
+ __skb_queue_purge(&cache->entries[i].skb_list);
+}
+
static inline struct ieee80211_fragment_entry *
-ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
+ieee80211_reassemble_add(struct ieee80211_fragment_cache *cache,
unsigned int frag, unsigned int seq, int rx_queue,
struct sk_buff **skb)
{
struct ieee80211_fragment_entry *entry;
- entry = &sdata->fragments[sdata->fragment_next++];
- if (sdata->fragment_next >= IEEE80211_FRAGMENT_MAX)
- sdata->fragment_next = 0;
+ entry = &cache->entries[cache->next++];
+ if (cache->next >= IEEE80211_FRAGMENT_MAX)
+ cache->next = 0;
- if (!skb_queue_empty(&entry->skb_list))
- __skb_queue_purge(&entry->skb_list);
+ __skb_queue_purge(&entry->skb_list);
__skb_queue_tail(&entry->skb_list, *skb); /* no need for locking */
*skb = NULL;
@@ -2111,14 +2126,14 @@ ieee80211_reassemble_add(struct ieee80211_sub_if_data *sdata,
}
static inline struct ieee80211_fragment_entry *
-ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
+ieee80211_reassemble_find(struct ieee80211_fragment_cache *cache,
unsigned int frag, unsigned int seq,
int rx_queue, struct ieee80211_hdr *hdr)
{
struct ieee80211_fragment_entry *entry;
int i, idx;
- idx = sdata->fragment_next;
+ idx = cache->next;
for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
struct ieee80211_hdr *f_hdr;
struct sk_buff *f_skb;
@@ -2127,7 +2142,7 @@ ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
if (idx < 0)
idx = IEEE80211_FRAGMENT_MAX - 1;
- entry = &sdata->fragments[idx];
+ entry = &cache->entries[idx];
if (skb_queue_empty(&entry->skb_list) || entry->seq != seq ||
entry->rx_queue != rx_queue ||
entry->last_frag + 1 != frag)
@@ -2155,15 +2170,27 @@ ieee80211_reassemble_find(struct ieee80211_sub_if_data *sdata,
return NULL;
}
+static bool requires_sequential_pn(struct ieee80211_rx_data *rx, __le16 fc)
+{
+ return rx->key &&
+ (rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP ||
+ rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP_256 ||
+ rx->key->conf.cipher == WLAN_CIPHER_SUITE_GCMP ||
+ rx->key->conf.cipher == WLAN_CIPHER_SUITE_GCMP_256) &&
+ ieee80211_has_protected(fc);
+}
+
static ieee80211_rx_result debug_noinline
ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
{
+ struct ieee80211_fragment_cache *cache = &rx->sdata->frags;
struct ieee80211_hdr *hdr;
u16 sc;
__le16 fc;
unsigned int frag, seq;
struct ieee80211_fragment_entry *entry;
struct sk_buff *skb;
+ struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
hdr = (struct ieee80211_hdr *)rx->skb->data;
fc = hdr->frame_control;
@@ -2179,6 +2206,9 @@ ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
goto out_no_led;
}
+ if (rx->sta)
+ cache = &rx->sta->frags;
+
if (likely(!ieee80211_has_morefrags(fc) && frag == 0))
goto out;
@@ -2197,20 +2227,17 @@ ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
if (frag == 0) {
/* This is the first fragment of a new frame. */
- entry = ieee80211_reassemble_add(rx->sdata, frag, seq,
+ entry = ieee80211_reassemble_add(cache, frag, seq,
rx->seqno_idx, &(rx->skb));
- if (rx->key &&
- (rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP ||
- rx->key->conf.cipher == WLAN_CIPHER_SUITE_CCMP_256 ||
- rx->key->conf.cipher == WLAN_CIPHER_SUITE_GCMP ||
- rx->key->conf.cipher == WLAN_CIPHER_SUITE_GCMP_256) &&
- ieee80211_has_protected(fc)) {
+ if (requires_sequential_pn(rx, fc)) {
int queue = rx->security_idx;
/* Store CCMP/GCMP PN so that we can verify that the
* next fragment has a sequential PN value.
*/
entry->check_sequential_pn = true;
+ entry->is_protected = true;
+ entry->key_color = rx->key->color;
memcpy(entry->last_pn,
rx->key->u.ccmp.rx_pn[queue],
IEEE80211_CCMP_PN_LEN);
@@ -2222,6 +2249,11 @@ ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
sizeof(rx->key->u.gcmp.rx_pn[queue]));
BUILD_BUG_ON(IEEE80211_CCMP_PN_LEN !=
IEEE80211_GCMP_PN_LEN);
+ } else if (rx->key &&
+ (ieee80211_has_protected(fc) ||
+ (status->flag & RX_FLAG_DECRYPTED))) {
+ entry->is_protected = true;
+ entry->key_color = rx->key->color;
}
return RX_QUEUED;
}
@@ -2229,7 +2261,7 @@ ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
/* This is a fragment for a frame that should already be pending in
* fragment cache. Add this fragment to the end of the pending entry.
*/
- entry = ieee80211_reassemble_find(rx->sdata, frag, seq,
+ entry = ieee80211_reassemble_find(cache, frag, seq,
rx->seqno_idx, hdr);
if (!entry) {
I802_DEBUG_INC(rx->local->rx_handlers_drop_defrag);
@@ -2244,25 +2276,39 @@ ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx)
if (entry->check_sequential_pn) {
int i;
u8 pn[IEEE80211_CCMP_PN_LEN], *rpn;
- int queue;
- if (!rx->key ||
- (rx->key->conf.cipher != WLAN_CIPHER_SUITE_CCMP &&
- rx->key->conf.cipher != WLAN_CIPHER_SUITE_CCMP_256 &&
- rx->key->conf.cipher != WLAN_CIPHER_SUITE_GCMP &&
- rx->key->conf.cipher != WLAN_CIPHER_SUITE_GCMP_256))
+ if (!requires_sequential_pn(rx, fc))
+ return RX_DROP_UNUSABLE;
+
+ /* Prevent mixed key and fragment cache attacks */
+ if (entry->key_color != rx->key->color)
return RX_DROP_UNUSABLE;
+
memcpy(pn, entry->last_pn, IEEE80211_CCMP_PN_LEN);
for (i = IEEE80211_CCMP_PN_LEN - 1; i >= 0; i--) {
pn[i]++;
if (pn[i])
break;
}
- queue = rx->security_idx;
- rpn = rx->key->u.ccmp.rx_pn[queue];
+
+ rpn = rx->ccm_gcm.pn;
if (memcmp(pn, rpn, IEEE80211_CCMP_PN_LEN))
return RX_DROP_UNUSABLE;
memcpy(entry->last_pn, pn, IEEE80211_CCMP_PN_LEN);
+ } else if (entry->is_protected &&
+ (!rx->key ||
+ (!ieee80211_has_protected(fc) &&
+ !(status->flag & RX_FLAG_DECRYPTED)) ||
+ rx->key->color != entry->key_color)) {
+ /* Drop this as a mixed key or fragment cache attack, even
+ * if for TKIP Michael MIC should protect us, and WEP is a
+ * lost cause anyway.
+ */
+ return RX_DROP_UNUSABLE;
+ } else if (entry->is_protected && rx->key &&
+ entry->key_color != rx->key->color &&
+ (status->flag & RX_FLAG_DECRYPTED)) {
+ return RX_DROP_UNUSABLE;
}
skb_pull(rx->skb, ieee80211_hdrlen(fc));
@@ -2422,13 +2468,13 @@ static bool ieee80211_frame_allowed(struct ieee80211_rx_data *rx, __le16 fc)
struct ethhdr *ehdr = (struct ethhdr *) rx->skb->data;
/*
- * Allow EAPOL frames to us/the PAE group address regardless
- * of whether the frame was encrypted or not.
+ * Allow EAPOL frames to us/the PAE group address regardless of
+ * whether the frame was encrypted or not, and always disallow
+ * all other destination addresses for them.
*/
- if (ehdr->h_proto == rx->sdata->control_port_protocol &&
- (ether_addr_equal(ehdr->h_dest, rx->sdata->vif.addr) ||
- ether_addr_equal(ehdr->h_dest, pae_group_addr)))
- return true;
+ if (unlikely(ehdr->h_proto == rx->sdata->control_port_protocol))
+ return ether_addr_equal(ehdr->h_dest, rx->sdata->vif.addr) ||
+ ether_addr_equal(ehdr->h_dest, pae_group_addr);
if (ieee80211_802_1x_port_control(rx) ||
ieee80211_drop_unencrypted(rx, fc))
@@ -2452,8 +2498,28 @@ static void ieee80211_deliver_skb_to_local_stack(struct sk_buff *skb,
cfg80211_rx_control_port(dev, skb, noencrypt);
dev_kfree_skb(skb);
} else {
+ struct ethhdr *ehdr = (void *)skb_mac_header(skb);
+
memset(skb->cb, 0, sizeof(skb->cb));
+ /*
+ * 802.1X over 802.11 requires that the authenticator address
+ * be used for EAPOL frames. However, 802.1X allows the use of
+ * the PAE group address instead. If the interface is part of
+ * a bridge and we pass the frame with the PAE group address,
+ * then the bridge will forward it to the network (even if the
+ * client was not associated yet), which isn't supposed to
+ * happen.
+ * To avoid that, rewrite the destination address to our own
+ * address, so that the authenticator (e.g. hostapd) will see
+ * the frame, but bridge won't forward it anywhere else. Note
+ * that due to earlier filtering, the only other address can
+ * be the PAE group address.
+ */
+ if (unlikely(skb->protocol == sdata->control_port_protocol &&
+ !ether_addr_equal(ehdr->h_dest, sdata->vif.addr)))
+ ether_addr_copy(ehdr->h_dest, sdata->vif.addr);
+
/* deliver to local stack */
if (rx->napi)
napi_gro_receive(rx->napi, skb);
@@ -2493,6 +2559,7 @@ ieee80211_deliver_skb(struct ieee80211_rx_data *rx)
if ((sdata->vif.type == NL80211_IFTYPE_AP ||
sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
!(sdata->flags & IEEE80211_SDATA_DONT_BRIDGE_PACKETS) &&
+ ehdr->h_proto != rx->sdata->control_port_protocol &&
(sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->u.vlan.sta)) {
if (is_multicast_ether_addr(ehdr->h_dest) &&
ieee80211_vif_get_num_mcast_if(sdata) != 0) {
@@ -2602,7 +2669,7 @@ __ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx, u8 data_offset)
if (ieee80211_data_to_8023_exthdr(skb, &ethhdr,
rx->sdata->vif.addr,
rx->sdata->vif.type,
- data_offset))
+ data_offset, true))
return RX_DROP_UNUSABLE;
ieee80211_amsdu_to_8023s(skb, &frame_list, dev->dev_addr,
@@ -2659,6 +2726,23 @@ ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx)
if (is_multicast_ether_addr(hdr->addr1))
return RX_DROP_UNUSABLE;
+ if (rx->key) {
+ /*
+ * We should not receive A-MSDUs on pre-HT connections,
+ * and HT connections cannot use old ciphers. Thus drop
+ * them, as in those cases we couldn't even have SPP
+ * A-MSDUs or such.
+ */
+ switch (rx->key->conf.cipher) {
+ case WLAN_CIPHER_SUITE_WEP40:
+ case WLAN_CIPHER_SUITE_WEP104:
+ case WLAN_CIPHER_SUITE_TKIP:
+ return RX_DROP_UNUSABLE;
+ default:
+ break;
+ }
+ }
+
return __ieee80211_rx_h_amsdu(rx, 0);
}
diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c
index ee72428..b506f2a 100644
--- a/net/mac80211/sta_info.c
+++ b/net/mac80211/sta_info.c
@@ -374,6 +374,8 @@ struct sta_info *sta_info_alloc(struct ieee80211_sub_if_data *sdata,
u64_stats_init(&sta->rx_stats.syncp);
+ ieee80211_init_frag_cache(&sta->frags);
+
sta->sta_state = IEEE80211_STA_NONE;
/* Mark TID as unreserved */
@@ -1085,6 +1087,8 @@ static void __sta_info_destroy_part2(struct sta_info *sta)
ieee80211_sta_debugfs_remove(sta);
+ ieee80211_destroy_frag_cache(&sta->frags);
+
cleanup_single_sta(sta);
}
diff --git a/net/mac80211/sta_info.h b/net/mac80211/sta_info.h
index 768000d..6611eae 100644
--- a/net/mac80211/sta_info.h
+++ b/net/mac80211/sta_info.h
@@ -432,6 +432,34 @@ struct ieee80211_sta_rx_stats {
u64 msdu[IEEE80211_NUM_TIDS + 1];
};
+/*
+ * IEEE 802.11-2016 (10.6 "Defragmentation") recommends support for "concurrent
+ * reception of at least one MSDU per access category per associated STA"
+ * on APs, or "at least one MSDU per access category" on other interface types.
+ *
+ * This limit can be increased by changing this define, at the cost of slower
+ * frame reassembly and increased memory use while fragments are pending.
+ */
+#define IEEE80211_FRAGMENT_MAX 4
+
+struct ieee80211_fragment_entry {
+ struct sk_buff_head skb_list;
+ unsigned long first_frag_time;
+ u16 seq;
+ u16 extra_len;
+ u16 last_frag;
+ u8 rx_queue;
+ u8 check_sequential_pn:1, /* needed for CCMP/GCMP */
+ is_protected:1;
+ u8 last_pn[6]; /* PN of the last fragment if CCMP was used */
+ unsigned int key_color;
+};
+
+struct ieee80211_fragment_cache {
+ struct ieee80211_fragment_entry entries[IEEE80211_FRAGMENT_MAX];
+ unsigned int next;
+};
+
/*
* The bandwidth threshold below which the per-station CoDel parameters will be
* scaled to be more lenient (to prevent starvation of slow stations). This
@@ -525,6 +553,7 @@ struct ieee80211_sta_rx_stats {
* @status_stats.last_ack_signal: last ACK signal
* @status_stats.ack_signal_filled: last ACK signal validity
* @status_stats.avg_ack_signal: average ACK signal
+ * @frags: fragment cache
*/
struct sta_info {
/* General information, mostly static */
@@ -630,6 +659,8 @@ struct sta_info {
struct cfg80211_chan_def tdls_chandef;
+ struct ieee80211_fragment_cache frags;
+
/* keep last! */
struct ieee80211_sta sta;
};
diff --git a/net/mac80211/wpa.c b/net/mac80211/wpa.c
index 690fe47..eb42d18 100644
--- a/net/mac80211/wpa.c
+++ b/net/mac80211/wpa.c
@@ -3,6 +3,7 @@
* Copyright 2002-2004, Instant802 Networks, Inc.
* Copyright 2008, Jouni Malinen <j@w1.fi>
* Copyright (C) 2016-2017 Intel Deutschland GmbH
+ * Copyright (C) 2020-2021 Intel Corporation
*/
#include <linux/netdevice.h>
@@ -167,8 +168,8 @@ ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx)
update_iv:
/* update IV in key information to be able to detect replays */
- rx->key->u.tkip.rx[rx->security_idx].iv32 = rx->tkip_iv32;
- rx->key->u.tkip.rx[rx->security_idx].iv16 = rx->tkip_iv16;
+ rx->key->u.tkip.rx[rx->security_idx].iv32 = rx->tkip.iv32;
+ rx->key->u.tkip.rx[rx->security_idx].iv16 = rx->tkip.iv16;
return RX_CONTINUE;
@@ -294,8 +295,8 @@ ieee80211_crypto_tkip_decrypt(struct ieee80211_rx_data *rx)
key, skb->data + hdrlen,
skb->len - hdrlen, rx->sta->sta.addr,
hdr->addr1, hwaccel, rx->security_idx,
- &rx->tkip_iv32,
- &rx->tkip_iv16);
+ &rx->tkip.iv32,
+ &rx->tkip.iv16);
if (res != TKIP_DECRYPT_OK)
return RX_DROP_UNUSABLE;
@@ -552,6 +553,8 @@ ieee80211_crypto_ccmp_decrypt(struct ieee80211_rx_data *rx,
}
memcpy(key->u.ccmp.rx_pn[queue], pn, IEEE80211_CCMP_PN_LEN);
+ if (unlikely(ieee80211_is_frag(hdr)))
+ memcpy(rx->ccm_gcm.pn, pn, IEEE80211_CCMP_PN_LEN);
}
/* Remove CCMP header and MIC */
@@ -782,6 +785,8 @@ ieee80211_crypto_gcmp_decrypt(struct ieee80211_rx_data *rx)
}
memcpy(key->u.gcmp.rx_pn[queue], pn, IEEE80211_GCMP_PN_LEN);
+ if (unlikely(ieee80211_is_frag(hdr)))
+ memcpy(rx->ccm_gcm.pn, pn, IEEE80211_CCMP_PN_LEN);
}
/* Remove GCMP header and MIC */
diff --git a/net/wireless/util.c b/net/wireless/util.c
index 734c4d0..981a225 100644
--- a/net/wireless/util.c
+++ b/net/wireless/util.c
@@ -449,7 +449,7 @@ EXPORT_SYMBOL(ieee80211_get_mesh_hdrlen);
int ieee80211_data_to_8023_exthdr(struct sk_buff *skb, struct ethhdr *ehdr,
const u8 *addr, enum nl80211_iftype iftype,
- u8 data_offset)
+ u8 data_offset, bool is_amsdu)
{
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
struct {
@@ -537,7 +537,7 @@ int ieee80211_data_to_8023_exthdr(struct sk_buff *skb, struct ethhdr *ehdr,
skb_copy_bits(skb, hdrlen, &payload, sizeof(payload));
tmp.h_proto = payload.proto;
- if (likely((ether_addr_equal(payload.hdr, rfc1042_header) &&
+ if (likely((!is_amsdu && ether_addr_equal(payload.hdr, rfc1042_header) &&
tmp.h_proto != htons(ETH_P_AARP) &&
tmp.h_proto != htons(ETH_P_IPX)) ||
ether_addr_equal(payload.hdr, bridge_tunnel_header)))
@@ -683,6 +683,9 @@ void ieee80211_amsdu_to_8023s(struct sk_buff *skb, struct sk_buff_head *list,
remaining = skb->len - offset;
if (subframe_len > remaining)
goto purge;
+ /* mitigate A-MSDU aggregation injection attacks */
+ if (ether_addr_equal(eth.h_dest, rfc1042_header))
+ goto purge;
offset += sizeof(struct ethhdr);
last = remaining <= subframe_len + padding;

View File

@ -20,7 +20,8 @@ SRC_URI = "http://www.kernel.org/pub/linux/kernel/projects/backports/stable/v${S
file://0004-backport-of-rt2x00-patches-from-openwrt.patch \
file://0005-backport-of-mwl-patches-from-openwrt.patch \
file://0006-backport-of-brcm-patches-from-openwrt.patch \
file://0007-backport-of-netmodule-patches-from-openwrt.patch \
file://0008-fragattack.patch \
file://0009-backport-of-netmodule-patches-from-openwrt.patch \
file://config.${NM_TARGET} \
"