linux-stable.git/net, branch v3.18.46

packet: fix race condition in packet_set_ring

2016-12-23T15:39:29+00:00

[ Upstream commit 84ac7260236a49c79eede91617700174c2c19b0c ]

When packet_set_ring creates a ring buffer it will initialize a
struct timer_list if the packet version is TPACKET_V3. This value
can then be raced by a different thread calling setsockopt to
set the version to TPACKET_V1 before packet_set_ring has finished.

This leads to a use-after-free on a function pointer in the
struct timer_list when the socket is closed as the previously
initialized timer will not be deleted.

The bug is fixed by taking lock_sock(sk) in packet_setsockopt when
changing the packet version while also taking the lock at the start
of packet_set_ring.

Fixes: f6fb8f100b80 ("af-packet: TPACKET_V3 flexible buffer implementation.")
Signed-off-by: Philip Pettersson 
Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

Bluetooth: Fix potential NULL dereference in RFCOMM bind callback

2016-12-23T15:39:29+00:00

[ Upstream commit 951b6a0717db97ce420547222647bcc40bf1eacd ]

addr can be NULL and it should not be dereferenced before NULL checking.

Signed-off-by: Jaganath Kanakkassery 
Signed-off-by: Marcel Holtmann 
Signed-off-by: Sasha Levin

mac80211: discard multicast and 4-addr A-MSDUs

2016-11-24T03:56:41+00:00

[ Upstream commit ea720935cf6686f72def9d322298bf7e9bd53377 ]

In mac80211, multicast A-MSDUs are accepted in many cases that
they shouldn't be accepted in:
 * drop A-MSDUs with a multicast A1 (RA), as required by the
   spec in 9.11 (802.11-2012 version)
 * drop A-MSDUs with a 4-addr header, since the fourth address
   can't actually be useful for them; unless 4-address frame
   format is actually requested, even though the fourth address
   is still not useful in this case, but ignored

Accepting the first case, in particular, is very problematic
since it allows anyone else with possession of a GTK to send
unicast frames encapsulated in a multicast A-MSDU, even when
the AP has client isolation enabled.

Cc: stable@vger.kernel.org
Signed-off-by: Johannes Berg 
Signed-off-by: Sasha Levin

udp: properly support MSG_PEEK with truncated buffers

2016-11-19T15:15:10+00:00

[ Upstream commit 197c949e7798fbf28cfadc69d9ca0c2abbf93191 ]

Backport of this upstream commit into stable kernels :
89c22d8c3b27 ("net: Fix skb csum races when peeking")
exposed a bug in udp stack vs MSG_PEEK support, when user provides
a buffer smaller than skb payload.

In this case,
skb_copy_and_csum_datagram_iovec(skb, sizeof(struct udphdr),
                                 msg->msg_iov);
returns -EFAULT.

This bug does not happen in upstream kernels since Al Viro did a great
job to replace this into :
skb_copy_and_csum_datagram_msg(skb, sizeof(struct udphdr), msg);
This variant is safe vs short buffers.

For the time being, instead reverting Herbert Xu patch and add back
skb->ip_summed invalid changes, simply store the result of
udp_lib_checksum_complete() so that we avoid computing the checksum a
second time, and avoid the problematic
skb_copy_and_csum_datagram_iovec() call.

This patch can be applied on recent kernels as it avoids a double
checksumming, then backported to stable kernels as a bug fix.

Signed-off-by: Eric Dumazet 
Acked-by: Herbert Xu 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

nl80211: validate number of probe response CSA counters

2016-10-06T02:40:20+00:00

[ Upstream commit ad5987b47e96a0fb6d13fea250e936aed000093c ]

Due to an apparent copy/paste bug, the number of counters for the
beacon configuration were checked twice, instead of checking the
number of probe response counters. Fix this to check the number of
probe response counters before parsing those.

Cc: stable@vger.kernel.org
Fixes: 9a774c78e211 ("cfg80211: Support multiple CSA counters")
Signed-off-by: Johannes Berg 
Signed-off-by: Sasha Levin

ipv6: addrconf: fix dev refcont leak when DAD failed

2016-10-06T02:40:20+00:00

[ Upstream commit 751eb6b6042a596b0080967c1a529a9fe98dac1d ]

In general, when DAD detected IPv6 duplicate address, ifp->state
will be set to INET6_IFADDR_STATE_ERRDAD and DAD is stopped by a
delayed work, the call tree should be like this:

ndisc_recv_ns
  -> addrconf_dad_failure        <- missing ifp put
     -> addrconf_mod_dad_work
       -> schedule addrconf_dad_work()
         -> addrconf_dad_stop()  <- missing ifp hold before call it

addrconf_dad_failure() called with ifp refcont holding but not put.
addrconf_dad_work() call addrconf_dad_stop() without extra holding
refcount. This will not cause any issue normally.

But the race between addrconf_dad_failure() and addrconf_dad_work()
may cause ifp refcount leak and netdevice can not be unregister,
dmesg show the following messages:

IPv6: eth0: IPv6 duplicate address fe80::XX:XXXX:XXXX:XX detected!
...
unregister_netdevice: waiting for eth0 to become free. Usage count = 1

Cc: stable@vger.kernel.org
Fixes: c15b1ccadb32 ("ipv6: move DAD and addrconf_verify processing
to workqueue")
Signed-off-by: Wei Yongjun 
Signed-off-by: David S. Miller 

Signed-off-by: Sasha Levin

Revert "wext: Fix 32 bit iwpriv compatibility issue with 64 bit Kernel"

2016-10-04T04:44:50+00:00

[ Upstream commit 4d0bd46a4d55383f7b925e6cf7865a77e0f0e020 ]

This reverts commit 3d5fdff46c4b2b9534fa2f9fc78e90a48e0ff724.

Ben Hutchings pointed out that the commit isn't safe since it assumes
that the structure used by the driver is iw_point, when in fact there's
no way to know about that.

Fortunately, the only driver in the tree that ever runs this code path
is the wilc1000 staging driver, so it doesn't really matter.

Clearly I should have investigated this better before applying, sorry.

Reported-by: Ben Hutchings 
Cc: stable@vger.kernel.org [though I guess it doesn't matter much]
Fixes: 3d5fdff46c4b ("wext: Fix 32 bit iwpriv compatibility issue with 64 bit Kernel")
Signed-off-by: Johannes Berg 
Signed-off-by: Sasha Levin

mac80211: fix purging multicast PS buffer queue

2016-08-31T23:25:44+00:00

[ Upstream commit 6b07d9ca9b5363dda959b9582a3fc9c0b89ef3b5 ]

The code currently assumes that buffered multicast PS frames don't have
a pending ACK frame for tx status reporting.
However, hostapd sends a broadcast deauth frame on teardown for which tx
status is requested. This can lead to the "Have pending ack frames"
warning on module reload.
Fix this by using ieee80211_free_txskb/ieee80211_purge_tx_queue.

Cc: stable@vger.kernel.org
Signed-off-by: Felix Fietkau 
Signed-off-by: Johannes Berg 
Signed-off-by: Sasha Levin

tcp: make challenge acks less predictable

2016-08-24T15:05:40+00:00

[ Upstream commit 75ff39ccc1bd5d3c455b6822ab09e533c551f758 ]

Yue Cao claims that current host rate limiting of challenge ACKS
(RFC 5961) could leak enough information to allow a patient attacker
to hijack TCP sessions. He will soon provide details in an academic
paper.

This patch increases the default limit from 100 to 1000, and adds
some randomization so that the attacker can no longer hijack
sessions without spending a considerable amount of probes.

Based on initial analysis and patch from Linus.

Note that we also have per socket rate limiting, so it is tempting
to remove the host limit in the future.

v2: randomize the count of challenge acks per second, not the period.

Fixes: 282f23c6ee34 ("tcp: implement RFC 5961 3.2")
Reported-by: Yue Cao 
Signed-off-by: Eric Dumazet 
Suggested-by: Linus Torvalds 
Cc: Yuchung Cheng 
Cc: Neal Cardwell 
Acked-by: Neal Cardwell 
Acked-by: Yuchung Cheng 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

net/irda: fix NULL pointer dereference on memory allocation failure

2016-08-22T16:23:18+00:00

[ Upstream commit d3e6952cfb7ba5f4bfa29d4803ba91f96ce1204d ]

I ran into this:

    kasan: CONFIG_KASAN_INLINE enabled
    kasan: GPF could be caused by NULL-ptr deref or user memory access
    general protection fault: 0000 [#1] PREEMPT SMP KASAN
    CPU: 2 PID: 2012 Comm: trinity-c3 Not tainted 4.7.0-rc7+ #19
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
    task: ffff8800b745f2c0 ti: ffff880111740000 task.ti: ffff880111740000
    RIP: 0010:[]  [] irttp_connect_request+0x36/0x710
    RSP: 0018:ffff880111747bb8  EFLAGS: 00010286
    RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000069dd8358
    RDX: 0000000000000009 RSI: 0000000000000027 RDI: 0000000000000048
    RBP: ffff880111747c00 R08: 0000000000000000 R09: 0000000000000000
    R10: 0000000069dd8358 R11: 1ffffffff0759723 R12: 0000000000000000
    R13: ffff88011a7e4780 R14: 0000000000000027 R15: 0000000000000000
    FS:  00007fc738404700(0000) GS:ffff88011af00000(0000) knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    CR2: 00007fc737fdfb10 CR3: 0000000118087000 CR4: 00000000000006e0
    Stack:
     0000000000000200 ffff880111747bd8 ffffffff810ee611 ffff880119f1f220
     ffff880119f1f4f8 ffff880119f1f4f0 ffff88011a7e4780 ffff880119f1f232
     ffff880119f1f220 ffff880111747d58 ffffffff82bca542 0000000000000000
    Call Trace:
     [] irda_connect+0x562/0x1190
     [] SYSC_connect+0x202/0x2a0
     [] SyS_connect+0x9/0x10
     [] do_syscall_64+0x19c/0x410
     [] entry_SYSCALL64_slow_path+0x25/0x25
    Code: 41 89 ca 48 89 e5 41 57 41 56 41 55 41 54 41 89 d7 53 48 89 fb 48 83 c7 48 48 89 fa 41 89 f6 48 c1 ea 03 48 83 ec 20 4c 8b 65 10 <0f> b6 04 02 84 c0 74 08 84 c0 0f 8e 4c 04 00 00 80 7b 48 00 74
    RIP  [] irttp_connect_request+0x36/0x710
     RSP 
    ---[ end trace 4cda2588bc055b30 ]---

The problem is that irda_open_tsap() can fail and leave self->tsap = NULL,
and then irttp_connect_request() almost immediately dereferences it.

Cc: stable@vger.kernel.org
Signed-off-by: Vegard Nossum 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin