linux-stable.git/net/wireless, branch v4.4.271

cfg80211: mitigate A-MSDU aggregation attacks

2021-06-03T06:22:05+00:00

commit 2b8a1fee3488c602aca8bea004a087e60806a5cf upstream.

Mitigate A-MSDU injection attacks (CVE-2020-24588) by detecting if the
destination address of a subframe equals an RFC1042 (i.e., LLC/SNAP)
header, and if so dropping the complete A-MSDU frame. This mitigates
known attacks, although new (unknown) aggregation-based attacks may
remain possible.

This defense works because in A-MSDU aggregation injection attacks, a
normal encrypted Wi-Fi frame is turned into an A-MSDU frame. This means
the first 6 bytes of the first A-MSDU subframe correspond to an RFC1042
header. In other words, the destination MAC address of the first A-MSDU
subframe contains the start of an RFC1042 header during an aggregation
attack. We can detect this and thereby prevent this specific attack.
For details, see Section 7.2 of "Fragment and Forge: Breaking Wi-Fi
Through Frame Aggregation and Fragmentation".

Note that for kernel 4.9 and above this patch depends on "mac80211:
properly handle A-MSDUs that start with a rfc1042 header". Otherwise
this patch has no impact and attacks will remain possible.

Cc: stable@vger.kernel.org
Signed-off-by: Mathy Vanhoef 
Link: https://lore.kernel.org/r/20210511200110.25d93176ddaf.I9e265b597f2cd23eb44573f35b625947b386a9de@changeid
Signed-off-by: Johannes Berg 
Signed-off-by: Greg Kroah-Hartman

mac80211: properly handle A-MSDUs that start with an RFC 1042 header

2021-06-03T06:22:05+00:00

commit a1d5ff5651ea592c67054233b14b30bf4452999c upstream.

Properly parse A-MSDUs whose first 6 bytes happen to equal a rfc1042
header. This can occur in practice when the destination MAC address
equals AA:AA:03:00:00:00. More importantly, this simplifies the next
patch to mitigate A-MSDU injection attacks.

Cc: stable@vger.kernel.org
Signed-off-by: Mathy Vanhoef 
Link: https://lore.kernel.org/r/20210511200110.0b2b886492f0.I23dd5d685fe16d3b0ec8106e8f01b59f499dffed@changeid
Signed-off-by: Johannes Berg 
Signed-off-by: Greg Kroah-Hartman

cfg80211: scan: drop entry from hidden_list on overflow

2021-05-22T08:38:21+00:00

commit 010bfbe768f7ecc876ffba92db30432de4997e2a upstream.

If we overflow the maximum number of BSS entries and free the
new entry, drop it from any hidden_list that it may have been
added to in the code above or in cfg80211_combine_bsses().

Reported-by: Dan Carpenter 
Link: https://lore.kernel.org/r/20210416094212.5de7d1676ad7.Ied283b0bc5f504845e7d6ab90626bdfa68bb3dc0@changeid
Cc: stable@vger.kernel.org
Signed-off-by: Johannes Berg 
Signed-off-by: Greg Kroah-Hartman

cfg80211: remove WARN_ON() in cfg80211_sme_connect

2021-04-16T10:00:22+00:00

commit 1b5ab825d9acc0f27d2f25c6252f3526832a9626 upstream.

A WARN_ON(wdev->conn) would trigger in cfg80211_sme_connect(), if multiple
send_msg(NL80211_CMD_CONNECT) system calls are made from the userland, which
should be anticipated and handled by the wireless driver. Remove this WARN_ON()
to prevent kernel panic if kernel is configured to "panic_on_warn".

Bug reported by syzbot.

Reported-by: syzbot+5f9392825de654244975@syzkaller.appspotmail.com
Signed-off-by: Du Cheng 
Link: https://lore.kernel.org/r/20210407162756.6101-1-ducheng2@gmail.com
Signed-off-by: Johannes Berg 
Signed-off-by: Greg Kroah-Hartman

wext: fix NULL-ptr-dereference with cfg80211's lack of commit()

2021-02-03T22:16:15+00:00

commit 5122565188bae59d507d90a9a9fd2fd6107f4439 upstream.

Since cfg80211 doesn't implement commit, we never really cared about
that code there (and it's configured out w/o CONFIG_WIRELESS_EXT).
After all, since it has no commit, it shouldn't return -EIWCOMMIT to
indicate commit is needed.

However, EIWCOMMIT is actually an alias for EINPROGRESS, which _can_
happen if e.g. we try to change the frequency but we're already in
the process of connecting to some network, and drivers could return
that value (or even cfg80211 itself might).

This then causes us to crash because dev->wireless_handlers is NULL
but we try to check dev->wireless_handlers->standard[0].

Fix this by also checking dev->wireless_handlers. Also simplify the
code a little bit.

Cc: stable@vger.kernel.org
Reported-by: syzbot+444248c79e117bc99f46@syzkaller.appspotmail.com
Reported-by: syzbot+8b2a88a09653d4084179@syzkaller.appspotmail.com
Link: https://lore.kernel.org/r/20210121171621.2076e4a37d5a.I5d9c72220fe7bb133fb718751da0180a57ecba4e@changeid
Signed-off-by: Johannes Berg 
Signed-off-by: Greg Kroah-Hartman

cfg80211: initialize rekey_data

2020-12-29T12:42:41+00:00

[ Upstream commit f495acd8851d7b345e5f0e521b2645b1e1f928a0 ]

In case we have old supplicant, the akm field is uninitialized.

Signed-off-by: Sara Sharon 
Signed-off-by: Luca Coelho 
Link: https://lore.kernel.org/r/iwlwifi.20201129172929.930f0ab7ebee.Ic546e384efab3f4a89f318eafddc3eb7d556aecb@changeid
Signed-off-by: Johannes Berg 
Signed-off-by: Sasha Levin

cfg80211: regulatory: Fix inconsistent format argument

2020-11-18T17:25:00+00:00

[ Upstream commit db18d20d1cb0fde16d518fb5ccd38679f174bc04 ]

Fix follow warning:
[net/wireless/reg.c:3619]: (warning) %d in format string (no. 2)
requires 'int' but the argument type is 'unsigned int'.

Reported-by: Hulk Robot 
Signed-off-by: Ye Bin 
Link: https://lore.kernel.org/r/20201009070215.63695-1-yebin10@huawei.com
Signed-off-by: Johannes Berg 
Signed-off-by: Sasha Levin

nl80211: fix non-split wiphy information

2020-10-29T08:03:05+00:00

[ Upstream commit ab10c22bc3b2024f0c9eafa463899a071eac8d97 ]

When dumping wiphy information, we try to split the data into
many submessages, but for old userspace we still support the
old mode where this doesn't happen.

However, in this case we were not resetting our state correctly
and dumping multiple messages for each wiphy, which would have
broken such older userspace.

This was broken pretty much immediately afterwards because it
only worked in the original commit where non-split dumps didn't
have any more data than split dumps...

Fixes: fe1abafd942f ("nl80211: re-add channel width and extended capa advertising")
Signed-off-by: Johannes Berg 
Link: https://lore.kernel.org/r/20200928130717.3e6d9c6bada2.Ie0f151a8d0d00a8e1e18f6a8c9244dd02496af67@changeid
Signed-off-by: Johannes Berg 
Signed-off-by: Sasha Levin

net: wireless: nl80211: fix out-of-bounds access in nl80211_del_key()

2020-10-14T07:46:22+00:00

commit 3dc289f8f139997f4e9d3cfccf8738f20d23e47b upstream.

In nl80211_parse_key(), key.idx is first initialized as -1.
If this value of key.idx remains unmodified and gets returned, and
nl80211_key_allowed() also returns 0, then rdev_del_key() gets called
with key.idx = -1.
This causes an out-of-bounds array access.

Handle this issue by checking if the value of key.idx after
nl80211_parse_key() is called and return -EINVAL if key.idx < 0.

Cc: stable@vger.kernel.org
Reported-by: syzbot+b1bb342d1d097516cbda@syzkaller.appspotmail.com
Tested-by: syzbot+b1bb342d1d097516cbda@syzkaller.appspotmail.com
Signed-off-by: Anant Thazhemadam 
Link: https://lore.kernel.org/r/20201007035401.9522-1-anant.thazhemadam@gmail.com
Signed-off-by: Johannes Berg 
Signed-off-by: Greg Kroah-Hartman

cfg80211: regulatory: reject invalid hints

2020-09-12T09:45:32+00:00

commit 47caf685a6854593348f216e0b489b71c10cbe03 upstream.

Reject invalid hints early in order to not cause a kernel
WARN later if they're restored to or similar.

Reported-by: syzbot+d451401ffd00a60677ee@syzkaller.appspotmail.com
Link: https://syzkaller.appspot.com/bug?extid=d451401ffd00a60677ee
Link: https://lore.kernel.org/r/20200819084648.13956-1-johannes@sipsolutions.net
Signed-off-by: Johannes Berg 
Signed-off-by: Greg Kroah-Hartman