From 2eb2756f6c9e9621e022d78321ce40a62c4520b5 Mon Sep 17 00:00:00 2001 From: Alexander Aring Date: Tue, 4 Oct 2022 21:47:49 -0400 Subject: Revert "net/ieee802154: reject zero-sized raw_sendmsg()" This reverts commit 3a4d061c699bd3eedc80dc97a4b2a2e1af83c6f5. There is a v2 which does return zero if zero length is given. Signed-off-by: Alexander Aring Link: https://lore.kernel.org/r/20221005014750.3685555-1-aahringo@redhat.com Signed-off-by: Stefan Schmidt --- net/ieee802154/socket.c | 3 --- 1 file changed, 3 deletions(-) (limited to 'net') diff --git a/net/ieee802154/socket.c b/net/ieee802154/socket.c index cbd0e2ac4ffe..7889e1ef7fad 100644 --- a/net/ieee802154/socket.c +++ b/net/ieee802154/socket.c @@ -251,9 +251,6 @@ static int raw_sendmsg(struct sock *sk, struct msghdr *msg, size_t size) return -EOPNOTSUPP; } - if (!size) - return -EINVAL; - lock_sock(sk); if (!sk->sk_bound_dev_if) dev = dev_getfirstbyhwtype(sock_net(sk), ARPHRD_IEEE802154); -- cgit v1.2.3 From b12e924a2f5b960373459c8f8a514f887adf5cac Mon Sep 17 00:00:00 2001 From: Tetsuo Handa Date: Tue, 4 Oct 2022 21:47:50 -0400 Subject: net/ieee802154: don't warn zero-sized raw_sendmsg() syzbot is hitting skb_assert_len() warning at __dev_queue_xmit() [1], for PF_IEEE802154 socket's zero-sized raw_sendmsg() request is hitting __dev_queue_xmit() with skb->len == 0. Since PF_IEEE802154 socket's zero-sized raw_sendmsg() request was able to return 0, don't call __dev_queue_xmit() if packet length is 0. ---------- #include #include int main(int argc, char *argv[]) { struct sockaddr_in addr = { .sin_family = AF_INET, .sin_addr.s_addr = htonl(INADDR_LOOPBACK) }; struct iovec iov = { }; struct msghdr hdr = { .msg_name = &addr, .msg_namelen = sizeof(addr), .msg_iov = &iov, .msg_iovlen = 1 }; sendmsg(socket(PF_IEEE802154, SOCK_RAW, 0), &hdr, 0); return 0; } ---------- Note that this might be a sign that commit fd1894224407c484 ("bpf: Don't redirect packets with invalid pkt_len") should be reverted, for skb->len == 0 was acceptable for at least PF_IEEE802154 socket. Link: https://syzkaller.appspot.com/bug?extid=5ea725c25d06fb9114c4 [1] Reported-by: syzbot Fixes: fd1894224407c484 ("bpf: Don't redirect packets with invalid pkt_len") Signed-off-by: Tetsuo Handa Signed-off-by: Alexander Aring Link: https://lore.kernel.org/r/20221005014750.3685555-2-aahringo@redhat.com Signed-off-by: Stefan Schmidt --- net/ieee802154/socket.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'net') diff --git a/net/ieee802154/socket.c b/net/ieee802154/socket.c index 7889e1ef7fad..6e55fae4c686 100644 --- a/net/ieee802154/socket.c +++ b/net/ieee802154/socket.c @@ -272,6 +272,10 @@ static int raw_sendmsg(struct sock *sk, struct msghdr *msg, size_t size) err = -EMSGSIZE; goto out_dev; } + if (!size) { + err = 0; + goto out_dev; + } hlen = LL_RESERVED_SPACE(dev); tlen = dev->needed_tailroom; -- cgit v1.2.3 From af7b29b1deaac6da3bb7637f0e263dfab7bfc7a3 Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Wed, 5 Oct 2022 01:01:00 +0300 Subject: Revert "net/sched: taprio: make qdisc_leaf() see the per-netdev-queue pfifo child qdiscs" taprio_attach() has this logic at the end, which should have been removed with the blamed patch (which is now being reverted): /* access to the child qdiscs is not needed in offload mode */ if (FULL_OFFLOAD_IS_ENABLED(q->flags)) { kfree(q->qdiscs); q->qdiscs = NULL; } because otherwise, we make use of q->qdiscs[] even after this array was deallocated, namely in taprio_leaf(). Therefore, whenever one would try to attach a valid child qdisc to a fully offloaded taprio root, one would immediately dereference a NULL pointer. $ tc qdisc replace dev eno0 handle 8001: parent root taprio \ num_tc 8 \ map 0 1 2 3 4 5 6 7 \ queues 1@0 1@1 1@2 1@3 1@4 1@5 1@6 1@7 \ max-sdu 0 0 0 0 0 200 0 0 \ base-time 200 \ sched-entry S 80 20000 \ sched-entry S a0 20000 \ sched-entry S 5f 60000 \ flags 2 $ max_frame_size=1500 $ data_rate_kbps=20000 $ port_transmit_rate_kbps=1000000 $ idleslope=$data_rate_kbps $ sendslope=$(($idleslope - $port_transmit_rate_kbps)) $ locredit=$(($max_frame_size * $sendslope / $port_transmit_rate_kbps)) $ hicredit=$(($max_frame_size * $idleslope / $port_transmit_rate_kbps)) $ tc qdisc replace dev eno0 parent 8001:7 cbs \ idleslope $idleslope \ sendslope $sendslope \ hicredit $hicredit \ locredit $locredit \ offload 0 Unable to handle kernel NULL pointer dereference at virtual address 0000000000000030 pc : taprio_leaf+0x28/0x40 lr : qdisc_leaf+0x3c/0x60 Call trace: taprio_leaf+0x28/0x40 tc_modify_qdisc+0xf0/0x72c rtnetlink_rcv_msg+0x12c/0x390 netlink_rcv_skb+0x5c/0x130 rtnetlink_rcv+0x1c/0x2c The solution is not as obvious as the problem. The code which deallocates q->qdiscs[] is in fact copied and pasted from mqprio, which also deallocates the array in mqprio_attach() and never uses it afterwards. Therefore, the identical cleanup logic of priv->qdiscs[] that mqprio_destroy() has is deceptive because it will never take place at qdisc_destroy() time, but just at raw ops->destroy() time (otherwise said, priv->qdiscs[] do not last for the entire lifetime of the mqprio root), but rather, this is just the twisted way in which the Qdisc API understands error path cleanup should be done (Qdisc_ops :: destroy() is called even when Qdisc_ops :: init() never succeeded). Side note, in fact this is also what the comment in mqprio_init() says: /* pre-allocate qdisc, attachment can't fail */ Or reworded, mqprio's priv->qdiscs[] scheme is only meant to serve as data passing between Qdisc_ops :: init() and Qdisc_ops :: attach(). [ this comment was also copied and pasted into the initial taprio commit, even though taprio_attach() came way later ] The problem is that taprio also makes extensive use of the q->qdiscs[] array in the software fast path (taprio_enqueue() and taprio_dequeue()), but it does not keep a reference of its own on q->qdiscs[i] (you'd think that since it creates these Qdiscs, it holds the reference, but nope, this is not completely true). To understand the difference between taprio_destroy() and mqprio_destroy() one must look before commit 13511704f8d7 ("net: taprio offload: enforce qdisc to netdev queue mapping"), because that just muddied the waters. In the "original" taprio design, taprio always attached itself (the root Qdisc) to all netdev TX queues, so that dev_qdisc_enqueue() would go through taprio_enqueue(). It also called qdisc_refcount_inc() on itself for as many times as there were netdev TX queues, in order to counter-balance what tc_get_qdisc() does when destroying a Qdisc (simplified for brevity below): if (n->nlmsg_type == RTM_DELQDISC) err = qdisc_graft(dev, parent=NULL, new=NULL, q, extack); qdisc_graft(where "new" is NULL so this deletes the Qdisc): for (i = 0; i < num_q; i++) { struct netdev_queue *dev_queue; dev_queue = netdev_get_tx_queue(dev, i); old = dev_graft_qdisc(dev_queue, new); if (new && i > 0) qdisc_refcount_inc(new); qdisc_put(old); ~~~~~~~~~~~~~~ this decrements taprio's refcount once for each TX queue } notify_and_destroy(net, skb, n, classid, rtnl_dereference(dev->qdisc), new); ~~~~~~~~~~~~~~~~~~~~~~~~~~~~ and this finally decrements it to zero, making qdisc_put() call qdisc_destroy() The q->qdiscs[] created using qdisc_create_dflt() (or their replacements, if taprio_graft() was ever to get called) were then privately freed by taprio_destroy(). This is still what is happening after commit 13511704f8d7 ("net: taprio offload: enforce qdisc to netdev queue mapping"), but only for software mode. In full offload mode, the per-txq "qdisc_put(old)" calls from qdisc_graft() now deallocate the child Qdiscs rather than decrement taprio's refcount. So when notify_and_destroy(taprio) finally calls taprio_destroy(), the difference is that the child Qdiscs were already deallocated. And this is exactly why the taprio_attach() comment "access to the child qdiscs is not needed in offload mode" is deceptive too. Not only the q->qdiscs[] array is not needed, but it is also necessary to get rid of it as soon as possible, because otherwise, we will also call qdisc_put() on the child Qdiscs in qdisc_destroy() -> taprio_destroy(), and this will cause a nasty use-after-free/refcount-saturate/whatever. In short, the problem is that since the blamed commit, taprio_leaf() needs q->qdiscs[] to not be freed by taprio_attach(), while qdisc_destroy() -> taprio_destroy() does need q->qdiscs[] to be freed by taprio_attach() for full offload. Fixing one problem triggers the other. All of this can be solved by making taprio keep its q->qdiscs[i] with a refcount elevated at 2 (in offloaded mode where they are attached to the netdev TX queues), both in taprio_attach() and in taprio_graft(). The generic qdisc_graft() would just decrement the child qdiscs' refcounts to 1, and taprio_destroy() would give them the final coup de grace. However the rabbit hole of changes is getting quite deep, and the complexity increases. The blamed commit was supposed to be a bug fix in the first place, and the bug it addressed is not so significant so as to justify further rework in stable trees. So I'd rather just revert it. I don't know enough about multi-queue Qdisc design to make a proper judgement right now regarding what is/isn't idiomatic use of Qdisc concepts in taprio. I will try to study the problem more and come with a different solution in net-next. Fixes: 1461d212ab27 ("net/sched: taprio: make qdisc_leaf() see the per-netdev-queue pfifo child qdiscs") Reported-by: Muhammad Husaini Zulkifli Reported-by: Vinicius Costa Gomes Signed-off-by: Vladimir Oltean Reviewed-by: Vinicius Costa Gomes Link: https://lore.kernel.org/r/20221004220100.1650558-1-vladimir.oltean@nxp.com Signed-off-by: Jakub Kicinski --- net/sched/sch_taprio.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) (limited to 'net') diff --git a/net/sched/sch_taprio.c b/net/sched/sch_taprio.c index 435d866fcfa0..570389f6cdd7 100644 --- a/net/sched/sch_taprio.c +++ b/net/sched/sch_taprio.c @@ -2043,14 +2043,12 @@ start_error: static struct Qdisc *taprio_leaf(struct Qdisc *sch, unsigned long cl) { - struct taprio_sched *q = qdisc_priv(sch); - struct net_device *dev = qdisc_dev(sch); - unsigned int ntx = cl - 1; + struct netdev_queue *dev_queue = taprio_queue_get(sch, cl); - if (ntx >= dev->num_tx_queues) + if (!dev_queue) return NULL; - return q->qdiscs[ntx]; + return dev_queue->qdisc_sleeping; } static unsigned long taprio_find(struct Qdisc *sch, u32 classid) -- cgit v1.2.3 From 61b91eb33a69c3be11b259c5ea484505cd79f883 Mon Sep 17 00:00:00 2001 From: David Ahern Date: Thu, 6 Oct 2022 10:48:49 -0600 Subject: ipv4: Handle attempt to delete multipath route when fib_info contains an nh reference Gwangun Jung reported a slab-out-of-bounds access in fib_nh_match: fib_nh_match+0xf98/0x1130 linux-6.0-rc7/net/ipv4/fib_semantics.c:961 fib_table_delete+0x5f3/0xa40 linux-6.0-rc7/net/ipv4/fib_trie.c:1753 inet_rtm_delroute+0x2b3/0x380 linux-6.0-rc7/net/ipv4/fib_frontend.c:874 Separate nexthop objects are mutually exclusive with the legacy multipath spec. Fix fib_nh_match to return if the config for the to be deleted route contains a multipath spec while the fib_info is using a nexthop object. Fixes: 493ced1ac47c ("ipv4: Allow routes to use nexthop objects") Fixes: 6bf92d70e690 ("net: ipv4: fix route with nexthop object delete warning") Reported-by: Gwangun Jung Signed-off-by: David Ahern Reviewed-by: Ido Schimmel Tested-by: Ido Schimmel Signed-off-by: David S. Miller --- net/ipv4/fib_semantics.c | 8 ++++---- tools/testing/selftests/net/fib_nexthops.sh | 5 +++++ 2 files changed, 9 insertions(+), 4 deletions(-) (limited to 'net') diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c index 2dc97583d279..e9a7f70a54df 100644 --- a/net/ipv4/fib_semantics.c +++ b/net/ipv4/fib_semantics.c @@ -888,13 +888,13 @@ int fib_nh_match(struct net *net, struct fib_config *cfg, struct fib_info *fi, return 1; } + /* cannot match on nexthop object attributes */ + if (fi->nh) + return 1; + if (cfg->fc_oif || cfg->fc_gw_family) { struct fib_nh *nh; - /* cannot match on nexthop object attributes */ - if (fi->nh) - return 1; - nh = fib_info_nh(fi, 0); if (cfg->fc_encap) { if (fib_encap_match(net, cfg->fc_encap_type, diff --git a/tools/testing/selftests/net/fib_nexthops.sh b/tools/testing/selftests/net/fib_nexthops.sh index d5a0dd548989..ee5e98204d3d 100755 --- a/tools/testing/selftests/net/fib_nexthops.sh +++ b/tools/testing/selftests/net/fib_nexthops.sh @@ -1223,6 +1223,11 @@ ipv4_fcnal() log_test $rc 0 "Delete nexthop route warning" run_cmd "$IP route delete 172.16.101.1/32 nhid 12" run_cmd "$IP nexthop del id 12" + + run_cmd "$IP nexthop add id 21 via 172.16.1.6 dev veth1" + run_cmd "$IP ro add 172.16.101.0/24 nhid 21" + run_cmd "$IP ro del 172.16.101.0/24 nexthop via 172.16.1.7 dev veth1 nexthop via 172.16.1.8 dev veth1" + log_test $? 2 "Delete multipath route with only nh id based entry" } ipv4_grp_fcnal() -- cgit v1.2.3 From 557f050166e523ce86018d7a43e7d543d9598b3d Mon Sep 17 00:00:00 2001 From: Yang Yingliang Date: Sat, 8 Oct 2022 16:39:42 +0800 Subject: net: dsa: fix wrong pointer passed to PTR_ERR() in dsa_port_phylink_create() Fix wrong pointer passed to PTR_ERR() in dsa_port_phylink_create() to print error message. Fixes: cf5ca4ddc37a ("net: dsa: don't leave dangling pointers in dp->pl when failing") Signed-off-by: Yang Yingliang Reviewed-by: Vladimir Oltean Signed-off-by: David S. Miller --- net/dsa/port.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net') diff --git a/net/dsa/port.c b/net/dsa/port.c index e4a0513816bb..208168276995 100644 --- a/net/dsa/port.c +++ b/net/dsa/port.c @@ -1681,7 +1681,7 @@ int dsa_port_phylink_create(struct dsa_port *dp) pl = phylink_create(&dp->pl_config, of_fwnode_handle(dp->dn), mode, &dsa_port_phylink_mac_ops); if (IS_ERR(pl)) { - pr_err("error creating PHYLINK: %ld\n", PTR_ERR(dp->pl)); + pr_err("error creating PHYLINK: %ld\n", PTR_ERR(pl)); return PTR_ERR(pl); } -- cgit v1.2.3 From aebe9f4639b13a1f4e9a6b42cdd2e38c617b442d Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Wed, 28 Sep 2022 21:56:15 +0200 Subject: wifi: cfg80211: fix u8 overflow in cfg80211_update_notlisted_nontrans() In the copy code of the elements, we do the following calculation to reach the end of the MBSSID element: /* copy the IEs after MBSSID */ cpy_len = mbssid[1] + 2; This looks fine, however, cpy_len is a u8, the same as mbssid[1], so the addition of two can overflow. In this case the subsequent memcpy() will overflow the allocated buffer, since it copies 256 bytes too much due to the way the allocation and memcpy() sizes are calculated. Fix this by using size_t for the cpy_len variable. This fixes CVE-2022-41674. Reported-by: Soenke Huster Tested-by: Soenke Huster Fixes: 0b8fb8235be8 ("cfg80211: Parsing of Multiple BSSID information in scanning") Reviewed-by: Kees Cook Signed-off-by: Johannes Berg --- net/wireless/scan.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net') diff --git a/net/wireless/scan.c b/net/wireless/scan.c index 5382fc2003db..62f8c10412ad 100644 --- a/net/wireless/scan.c +++ b/net/wireless/scan.c @@ -2279,7 +2279,7 @@ cfg80211_update_notlisted_nontrans(struct wiphy *wiphy, size_t new_ie_len; struct cfg80211_bss_ies *new_ies; const struct cfg80211_bss_ies *old; - u8 cpy_len; + size_t cpy_len; lockdep_assert_held(&wiphy_to_rdev(wiphy)->bss_lock); -- cgit v1.2.3 From 8f033d2becc24aa6bfd2a5c104407963560caabc Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Wed, 28 Sep 2022 22:01:37 +0200 Subject: wifi: cfg80211/mac80211: reject bad MBSSID elements Per spec, the maximum value for the MaxBSSID ('n') indicator is 8, and the minimum is 1 since a multiple BSSID set with just one BSSID doesn't make sense (the # of BSSIDs is limited by 2^n). Limit this in the parsing in both cfg80211 and mac80211, rejecting any elements with an invalid value. This fixes potentially bad shifts in the processing of these inside the cfg80211_gen_new_bssid() function later. I found this during the investigation of CVE-2022-41674 fixed by the previous patch. Fixes: 0b8fb8235be8 ("cfg80211: Parsing of Multiple BSSID information in scanning") Fixes: 78ac51f81532 ("mac80211: support multi-bssid") Reviewed-by: Kees Cook Signed-off-by: Johannes Berg --- net/mac80211/util.c | 2 ++ net/wireless/scan.c | 2 ++ 2 files changed, 4 insertions(+) (limited to 'net') diff --git a/net/mac80211/util.c b/net/mac80211/util.c index bf7461c41bef..f61289c5fed2 100644 --- a/net/mac80211/util.c +++ b/net/mac80211/util.c @@ -1445,6 +1445,8 @@ static size_t ieee802_11_find_bssid_profile(const u8 *start, size_t len, for_each_element_id(elem, WLAN_EID_MULTIPLE_BSSID, start, len) { if (elem->datalen < 2) continue; + if (elem->data[0] < 1 || elem->data[0] > 8) + continue; for_each_element(sub, elem->data + 1, elem->datalen - 1) { u8 new_bssid[ETH_ALEN]; diff --git a/net/wireless/scan.c b/net/wireless/scan.c index 62f8c10412ad..5dab33e1f3a8 100644 --- a/net/wireless/scan.c +++ b/net/wireless/scan.c @@ -2143,6 +2143,8 @@ static void cfg80211_parse_mbssid_data(struct wiphy *wiphy, for_each_element_id(elem, WLAN_EID_MULTIPLE_BSSID, ie, ielen) { if (elem->datalen < 4) continue; + if (elem->data[0] < 1 || (int)elem->data[0] > 8) + continue; for_each_element(sub, elem->data + 1, elem->datalen - 1) { u8 profile_len; -- cgit v1.2.3 From ff05d4b45dd89b922578dac497dcabf57cf771c6 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Wed, 28 Sep 2022 22:07:15 +0200 Subject: wifi: mac80211: fix MBSSID parsing use-after-free When we parse a multi-BSSID element, we might point some element pointers into the allocated nontransmitted_profile. However, we free this before returning, causing UAF when the relevant pointers in the parsed elements are accessed. Fix this by not allocating the scratch buffer separately but as part of the returned structure instead, that way, there are no lifetime issues with it. The scratch buffer introduction as part of the returned data here is taken from MLO feature work done by Ilan. This fixes CVE-2022-42719. Fixes: 5023b14cf4df ("mac80211: support profile split between elements") Co-developed-by: Ilan Peer Signed-off-by: Ilan Peer Reviewed-by: Kees Cook Signed-off-by: Johannes Berg --- net/mac80211/ieee80211_i.h | 8 ++++++++ net/mac80211/util.c | 30 +++++++++++++++--------------- 2 files changed, 23 insertions(+), 15 deletions(-) (limited to 'net') diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h index 4e1d4c339f2d..a842f2e1c230 100644 --- a/net/mac80211/ieee80211_i.h +++ b/net/mac80211/ieee80211_i.h @@ -1709,6 +1709,14 @@ struct ieee802_11_elems { /* whether a parse error occurred while retrieving these elements */ bool parse_error; + + /* + * scratch buffer that can be used for various element parsing related + * tasks, e.g., element de-fragmentation etc. + */ + size_t scratch_len; + u8 *scratch_pos; + u8 scratch[]; }; static inline struct ieee80211_local *hw_to_local( diff --git a/net/mac80211/util.c b/net/mac80211/util.c index f61289c5fed2..99e903299143 100644 --- a/net/mac80211/util.c +++ b/net/mac80211/util.c @@ -1506,24 +1506,26 @@ ieee802_11_parse_elems_full(struct ieee80211_elems_parse_params *params) const struct element *non_inherit = NULL; u8 *nontransmitted_profile; int nontransmitted_profile_len = 0; + size_t scratch_len = params->len; - elems = kzalloc(sizeof(*elems), GFP_ATOMIC); + elems = kzalloc(sizeof(*elems) + scratch_len, GFP_ATOMIC); if (!elems) return NULL; elems->ie_start = params->start; elems->total_len = params->len; - - nontransmitted_profile = kmalloc(params->len, GFP_ATOMIC); - if (nontransmitted_profile) { - nontransmitted_profile_len = - ieee802_11_find_bssid_profile(params->start, params->len, - elems, params->bss, - nontransmitted_profile); - non_inherit = - cfg80211_find_ext_elem(WLAN_EID_EXT_NON_INHERITANCE, - nontransmitted_profile, - nontransmitted_profile_len); - } + elems->scratch_len = scratch_len; + elems->scratch_pos = elems->scratch; + + nontransmitted_profile = elems->scratch_pos; + nontransmitted_profile_len = + ieee802_11_find_bssid_profile(params->start, params->len, + elems, params->bss, + nontransmitted_profile); + elems->scratch_pos += nontransmitted_profile_len; + elems->scratch_len -= nontransmitted_profile_len; + non_inherit = cfg80211_find_ext_elem(WLAN_EID_EXT_NON_INHERITANCE, + nontransmitted_profile, + nontransmitted_profile_len); elems->crc = _ieee802_11_parse_elems_full(params, elems, non_inherit); @@ -1557,8 +1559,6 @@ ieee802_11_parse_elems_full(struct ieee80211_elems_parse_params *params) offsetofend(struct ieee80211_bssid_index, dtim_count)) elems->dtim_count = elems->bssid_index->dtim_count; - kfree(nontransmitted_profile); - return elems; } -- cgit v1.2.3 From 567e14e39e8f8c6997a1378bc3be615afca86063 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Thu, 29 Sep 2022 21:50:44 +0200 Subject: wifi: cfg80211: ensure length byte is present before access When iterating the elements here, ensure the length byte is present before checking it to see if the entire element will fit into the buffer. Longer term, we should rewrite this code using the type-safe element iteration macros that check all of this. Fixes: 0b8fb8235be8 ("cfg80211: Parsing of Multiple BSSID information in scanning") Reported-by: Soenke Huster Signed-off-by: Johannes Berg --- net/wireless/scan.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'net') diff --git a/net/wireless/scan.c b/net/wireless/scan.c index 5dab33e1f3a8..a183f2b75874 100644 --- a/net/wireless/scan.c +++ b/net/wireless/scan.c @@ -304,7 +304,8 @@ static size_t cfg80211_gen_new_ie(const u8 *ie, size_t ielen, tmp_old = cfg80211_find_ie(WLAN_EID_SSID, ie, ielen); tmp_old = (tmp_old) ? tmp_old + tmp_old[1] + 2 : ie; - while (tmp_old + tmp_old[1] + 2 - ie <= ielen) { + while (tmp_old + 2 - ie <= ielen && + tmp_old + tmp_old[1] + 2 - ie <= ielen) { if (tmp_old[0] == 0) { tmp_old++; continue; @@ -364,7 +365,8 @@ static size_t cfg80211_gen_new_ie(const u8 *ie, size_t ielen, * copied to new ie, skip ssid, capability, bssid-index ie */ tmp_new = sub_copy; - while (tmp_new + tmp_new[1] + 2 - sub_copy <= subie_len) { + while (tmp_new + 2 - sub_copy <= subie_len && + tmp_new + tmp_new[1] + 2 - sub_copy <= subie_len) { if (!(tmp_new[0] == WLAN_EID_NON_TX_BSSID_CAP || tmp_new[0] == WLAN_EID_SSID)) { memcpy(pos, tmp_new, tmp_new[1] + 2); -- cgit v1.2.3 From 0b7808818cb9df6680f98996b8e9a439fa7bcc2f Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Fri, 30 Sep 2022 23:44:23 +0200 Subject: wifi: cfg80211: fix BSS refcounting bugs There are multiple refcounting bugs related to multi-BSSID: - In bss_ref_get(), if the BSS has a hidden_beacon_bss, then the bss pointer is overwritten before checking for the transmitted BSS, which is clearly wrong. Fix this by using the bss_from_pub() macro. - In cfg80211_bss_update() we copy the transmitted_bss pointer from tmp into new, but then if we release new, we'll unref it erroneously. We already set the pointer and ref it, but need to NULL it since it was copied from the tmp data. - In cfg80211_inform_single_bss_data(), if adding to the non- transmitted list fails, we unlink the BSS and yet still we return it, but this results in returning an entry without a reference. We shouldn't return it anyway if it was broken enough to not get added there. This fixes CVE-2022-42720. Reported-by: Sönke Huster Tested-by: Sönke Huster Fixes: a3584f56de1c ("cfg80211: Properly track transmitting and non-transmitting BSS") Signed-off-by: Johannes Berg --- net/wireless/scan.c | 27 ++++++++++++++------------- 1 file changed, 14 insertions(+), 13 deletions(-) (limited to 'net') diff --git a/net/wireless/scan.c b/net/wireless/scan.c index a183f2b75874..249107212c09 100644 --- a/net/wireless/scan.c +++ b/net/wireless/scan.c @@ -143,18 +143,12 @@ static inline void bss_ref_get(struct cfg80211_registered_device *rdev, lockdep_assert_held(&rdev->bss_lock); bss->refcount++; - if (bss->pub.hidden_beacon_bss) { - bss = container_of(bss->pub.hidden_beacon_bss, - struct cfg80211_internal_bss, - pub); - bss->refcount++; - } - if (bss->pub.transmitted_bss) { - bss = container_of(bss->pub.transmitted_bss, - struct cfg80211_internal_bss, - pub); - bss->refcount++; - } + + if (bss->pub.hidden_beacon_bss) + bss_from_pub(bss->pub.hidden_beacon_bss)->refcount++; + + if (bss->pub.transmitted_bss) + bss_from_pub(bss->pub.transmitted_bss)->refcount++; } static inline void bss_ref_put(struct cfg80211_registered_device *rdev, @@ -1741,6 +1735,8 @@ cfg80211_bss_update(struct cfg80211_registered_device *rdev, new->refcount = 1; INIT_LIST_HEAD(&new->hidden_list); INIT_LIST_HEAD(&new->pub.nontrans_list); + /* we'll set this later if it was non-NULL */ + new->pub.transmitted_bss = NULL; if (rcu_access_pointer(tmp->pub.proberesp_ies)) { hidden = rb_find_bss(rdev, tmp, BSS_CMP_HIDE_ZLEN); @@ -2023,10 +2019,15 @@ cfg80211_inform_single_bss_data(struct wiphy *wiphy, spin_lock_bh(&rdev->bss_lock); if (cfg80211_add_nontrans_list(non_tx_data->tx_bss, &res->pub)) { - if (__cfg80211_unlink_bss(rdev, res)) + if (__cfg80211_unlink_bss(rdev, res)) { rdev->bss_generation++; + res = NULL; + } } spin_unlock_bh(&rdev->bss_lock); + + if (!res) + return NULL; } trace_cfg80211_return_bss(&res->pub); -- cgit v1.2.3 From bcca852027e5878aec911a347407ecc88d6fff7f Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Sat, 1 Oct 2022 00:01:44 +0200 Subject: wifi: cfg80211: avoid nontransmitted BSS list corruption If a non-transmitted BSS shares enough information (both SSID and BSSID!) with another non-transmitted BSS of a different AP, then we can find and update it, and then try to add it to the non-transmitted BSS list. We do a search for it on the transmitted BSS, but if it's not there (but belongs to another transmitted BSS), the list gets corrupted. Since this is an erroneous situation, simply fail the list insertion in this case and free the non-transmitted BSS. This fixes CVE-2022-42721. Reported-by: Sönke Huster Tested-by: Sönke Huster Fixes: 0b8fb8235be8 ("cfg80211: Parsing of Multiple BSSID information in scanning") Signed-off-by: Johannes Berg --- net/wireless/scan.c | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'net') diff --git a/net/wireless/scan.c b/net/wireless/scan.c index 249107212c09..703b05c6c43e 100644 --- a/net/wireless/scan.c +++ b/net/wireless/scan.c @@ -423,6 +423,15 @@ cfg80211_add_nontrans_list(struct cfg80211_bss *trans_bss, rcu_read_unlock(); + /* + * This is a bit weird - it's not on the list, but already on another + * one! The only way that could happen is if there's some BSSID/SSID + * shared by multiple APs in their multi-BSSID profiles, potentially + * with hidden SSID mixed in ... ignore it. + */ + if (!list_empty(&nontrans_bss->nontrans_list)) + return -EINVAL; + /* add to the list */ list_add_tail(&nontrans_bss->nontrans_list, &trans_bss->nontrans_list); return 0; -- cgit v1.2.3 From b2d03cabe2b2e150ff5a381731ea0355459be09f Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Wed, 5 Oct 2022 21:24:10 +0200 Subject: wifi: mac80211: fix crash in beacon protection for P2P-device If beacon protection is active but the beacon cannot be decrypted or is otherwise malformed, we call the cfg80211 API to report this to userspace, but that uses a netdev pointer, which isn't present for P2P-Device. Fix this to call it only conditionally to ensure cfg80211 won't crash in the case of P2P-Device. This fixes CVE-2022-42722. Reported-by: Sönke Huster Fixes: 9eaf183af741 ("mac80211: Report beacon protection failures to user space") Signed-off-by: Johannes Berg --- net/mac80211/rx.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) (limited to 'net') diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c index bd215fe3c796..6001adc0a00e 100644 --- a/net/mac80211/rx.c +++ b/net/mac80211/rx.c @@ -1978,10 +1978,11 @@ ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx) if (mmie_keyidx < NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS || mmie_keyidx >= NUM_DEFAULT_KEYS + NUM_DEFAULT_MGMT_KEYS + - NUM_DEFAULT_BEACON_KEYS) { - cfg80211_rx_unprot_mlme_mgmt(rx->sdata->dev, - skb->data, - skb->len); + NUM_DEFAULT_BEACON_KEYS) { + if (rx->sdata->dev) + cfg80211_rx_unprot_mlme_mgmt(rx->sdata->dev, + skb->data, + skb->len); return RX_DROP_MONITOR; /* unexpected BIP keyidx */ } @@ -2131,7 +2132,8 @@ ieee80211_rx_h_decrypt(struct ieee80211_rx_data *rx) /* either the frame has been decrypted or will be dropped */ status->flag |= RX_FLAG_DECRYPTED; - if (unlikely(ieee80211_is_beacon(fc) && result == RX_DROP_UNUSABLE)) + if (unlikely(ieee80211_is_beacon(fc) && result == RX_DROP_UNUSABLE && + rx->sdata->dev)) cfg80211_rx_unprot_mlme_mgmt(rx->sdata->dev, skb->data, skb->len); -- cgit v1.2.3 From c90b93b5b782891ebfda49d4e5da36632fefd5d1 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Wed, 5 Oct 2022 23:11:43 +0200 Subject: wifi: cfg80211: update hidden BSSes to avoid WARN_ON When updating beacon elements in a non-transmitted BSS, also update the hidden sub-entries to the same beacon elements, so that a future update through other paths won't trigger a WARN_ON(). The warning is triggered because the beacon elements in the hidden BSSes that are children of the BSS should always be the same as in the parent. Reported-by: Sönke Huster Tested-by: Sönke Huster Fixes: 0b8fb8235be8 ("cfg80211: Parsing of Multiple BSSID information in scanning") Signed-off-by: Johannes Berg --- net/wireless/scan.c | 31 ++++++++++++++++++++----------- 1 file changed, 20 insertions(+), 11 deletions(-) (limited to 'net') diff --git a/net/wireless/scan.c b/net/wireless/scan.c index 703b05c6c43e..806a5f1330ff 100644 --- a/net/wireless/scan.c +++ b/net/wireless/scan.c @@ -1607,6 +1607,23 @@ struct cfg80211_non_tx_bss { u8 bssid_index; }; +static void cfg80211_update_hidden_bsses(struct cfg80211_internal_bss *known, + const struct cfg80211_bss_ies *new_ies, + const struct cfg80211_bss_ies *old_ies) +{ + struct cfg80211_internal_bss *bss; + + /* Assign beacon IEs to all sub entries */ + list_for_each_entry(bss, &known->hidden_list, hidden_list) { + const struct cfg80211_bss_ies *ies; + + ies = rcu_access_pointer(bss->pub.beacon_ies); + WARN_ON(ies != old_ies); + + rcu_assign_pointer(bss->pub.beacon_ies, new_ies); + } +} + static bool cfg80211_update_known_bss(struct cfg80211_registered_device *rdev, struct cfg80211_internal_bss *known, @@ -1630,7 +1647,6 @@ cfg80211_update_known_bss(struct cfg80211_registered_device *rdev, kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head); } else if (rcu_access_pointer(new->pub.beacon_ies)) { const struct cfg80211_bss_ies *old; - struct cfg80211_internal_bss *bss; if (known->pub.hidden_beacon_bss && !list_empty(&known->hidden_list)) { @@ -1658,16 +1674,7 @@ cfg80211_update_known_bss(struct cfg80211_registered_device *rdev, if (old == rcu_access_pointer(known->pub.ies)) rcu_assign_pointer(known->pub.ies, new->pub.beacon_ies); - /* Assign beacon IEs to all sub entries */ - list_for_each_entry(bss, &known->hidden_list, hidden_list) { - const struct cfg80211_bss_ies *ies; - - ies = rcu_access_pointer(bss->pub.beacon_ies); - WARN_ON(ies != old); - - rcu_assign_pointer(bss->pub.beacon_ies, - new->pub.beacon_ies); - } + cfg80211_update_hidden_bsses(known, new->pub.beacon_ies, old); if (old) kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head); @@ -2360,6 +2367,8 @@ cfg80211_update_notlisted_nontrans(struct wiphy *wiphy, } else { old = rcu_access_pointer(nontrans_bss->beacon_ies); rcu_assign_pointer(nontrans_bss->beacon_ies, new_ies); + cfg80211_update_hidden_bsses(bss_from_pub(nontrans_bss), + new_ies, old); rcu_assign_pointer(nontrans_bss->ies, new_ies); if (old) kfree_rcu((struct cfg80211_bss_ies *)old, rcu_head); -- cgit v1.2.3