summaryrefslogtreecommitdiff
path: root/net
AgeCommit message (Collapse)Author
2016-01-31batman-adv: Avoid recursive call_rcu for batadv_nc_nodeSven Eckelmann
[ Upstream commit 44e8e7e91d6c7c7ab19688750f7257292640d1a0 ] The batadv_nc_node_free_ref function uses call_rcu to delay the free of the batadv_nc_node object until no (already started) rcu_read_lock is enabled anymore. This makes sure that no context is still trying to access the object which should be removed. But batadv_nc_node also contains a reference to orig_node which must be removed. The reference drop of orig_node was done in the call_rcu function batadv_nc_node_free_rcu but should actually be done in the batadv_nc_node_release function to avoid nested call_rcus. This is important because rcu_barrier (e.g. batadv_softif_free or batadv_exit) will not detect the inner call_rcu as relevant for its execution. Otherwise this barrier will most likely be inserted in the queue before the callback of the first call_rcu was executed. The caller of rcu_barrier will therefore continue to run before the inner call_rcu callback finished. Fixes: d56b1705e28c ("batman-adv: network coding - detect coding nodes and remove these after timeout") Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <a@unstable.cc> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-31batman-adv: Avoid recursive call_rcu for batadv_bla_claimSven Eckelmann
[ Upstream commit 63b399272294e7a939cde41792dca38c549f0484 ] The batadv_claim_free_ref function uses call_rcu to delay the free of the batadv_bla_claim object until no (already started) rcu_read_lock is enabled anymore. This makes sure that no context is still trying to access the object which should be removed. But batadv_bla_claim also contains a reference to backbone_gw which must be removed. The reference drop of backbone_gw was done in the call_rcu function batadv_claim_free_rcu but should actually be done in the batadv_claim_release function to avoid nested call_rcus. This is important because rcu_barrier (e.g. batadv_softif_free or batadv_exit) will not detect the inner call_rcu as relevant for its execution. Otherwise this barrier will most likely be inserted in the queue before the callback of the first call_rcu was executed. The caller of rcu_barrier will therefore continue to run before the inner call_rcu callback finished. Fixes: 23721387c409 ("batman-adv: add basic bridge loop avoidance code") Signed-off-by: Sven Eckelmann <sven@narfation.org> Acked-by: Simon Wunderlich <sw@simonwunderlich.de> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <a@unstable.cc> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-31tcp/dccp: fix timewait races in timer handlingEric Dumazet
[ Upstream commit ed2e923945892a8372ab70d2f61d364b0b6d9054 ] When creating a timewait socket, we need to arm the timer before allowing other cpus to find it. The signal allowing cpus to find the socket is setting tw_refcnt to non zero value. As we set tw_refcnt in __inet_twsk_hashdance(), we therefore need to call inet_twsk_schedule() first. This also means we need to remove tw_refcnt changes from inet_twsk_schedule() and let the caller handle it. Note that because we use mod_timer_pinned(), we have the guarantee the timer wont expire before we set tw_refcnt as we run in BH context. To make things more readable I introduced inet_twsk_reschedule() helper. When rearming the timer, we can use mod_timer_pending() to make sure we do not rearm a canceled timer. Note: This bug can possibly trigger if packets of a flow can hit multiple cpus. This does not normally happen, unless flow steering is broken somehow. This explains this bug was spotted ~5 months after its introduction. A similar fix is needed for SYN_RECV sockets in reqsk_queue_hash_req(), but will be provided in a separate patch for proper tracking. Fixes: 789f558cfb36 ("tcp/dccp: get rid of central timewait timer") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Ying Cai <ycai@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-31bridge: fix lockdep addr_list_lock false positive splatNikolay Aleksandrov
[ Upstream commit c6894dec8ea9ae05747124dce98b3b5c2e69b168 ] After promisc mode management was introduced a bridge device could do dev_set_promiscuity from its ndo_change_rx_flags() callback which in turn can be called after the bridge's addr_list_lock has been taken (e.g. by dev_uc_add). This causes a false positive lockdep splat because the port interfaces' addr_list_lock is taken when br_manage_promisc() runs after the bridge's addr list lock was already taken. To remove the false positive introduce a custom bridge addr_list_lock class and set it on bridge init. A simple way to reproduce this is with the following: $ brctl addbr br0 $ ip l add l br0 br0.100 type vlan id 100 $ ip l set br0 up $ ip l set br0.100 up $ echo 1 > /sys/class/net/br0/bridge/vlan_filtering $ brctl addif br0 eth0 Splat: [ 43.684325] ============================================= [ 43.684485] [ INFO: possible recursive locking detected ] [ 43.684636] 4.4.0-rc8+ #54 Not tainted [ 43.684755] --------------------------------------------- [ 43.684906] brctl/1187 is trying to acquire lock: [ 43.685047] (_xmit_ETHER){+.....}, at: [<ffffffff8150169e>] dev_set_rx_mode+0x1e/0x40 [ 43.685460] but task is already holding lock: [ 43.685618] (_xmit_ETHER){+.....}, at: [<ffffffff815072a7>] dev_uc_add+0x27/0x80 [ 43.686015] other info that might help us debug this: [ 43.686316] Possible unsafe locking scenario: [ 43.686743] CPU0 [ 43.686967] ---- [ 43.687197] lock(_xmit_ETHER); [ 43.687544] lock(_xmit_ETHER); [ 43.687886] *** DEADLOCK *** [ 43.688438] May be due to missing lock nesting notation [ 43.688882] 2 locks held by brctl/1187: [ 43.689134] #0: (rtnl_mutex){+.+.+.}, at: [<ffffffff81510317>] rtnl_lock+0x17/0x20 [ 43.689852] #1: (_xmit_ETHER){+.....}, at: [<ffffffff815072a7>] dev_uc_add+0x27/0x80 [ 43.690575] stack backtrace: [ 43.690970] CPU: 0 PID: 1187 Comm: brctl Not tainted 4.4.0-rc8+ #54 [ 43.691270] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.8.1-20150318_183358- 04/01/2014 [ 43.691770] ffffffff826a25c0 ffff8800369fb8e0 ffffffff81360ceb ffffffff826a25c0 [ 43.692425] ffff8800369fb9b8 ffffffff810d0466 ffff8800369fb968 ffffffff81537139 [ 43.693071] ffff88003a08c880 0000000000000000 00000000ffffffff 0000000002080020 [ 43.693709] Call Trace: [ 43.693931] [<ffffffff81360ceb>] dump_stack+0x4b/0x70 [ 43.694199] [<ffffffff810d0466>] __lock_acquire+0x1e46/0x1e90 [ 43.694483] [<ffffffff81537139>] ? netlink_broadcast_filtered+0x139/0x3e0 [ 43.694789] [<ffffffff8153b5da>] ? nlmsg_notify+0x5a/0xc0 [ 43.695064] [<ffffffff810d10f5>] lock_acquire+0xe5/0x1f0 [ 43.695340] [<ffffffff8150169e>] ? dev_set_rx_mode+0x1e/0x40 [ 43.695623] [<ffffffff815edea5>] _raw_spin_lock_bh+0x45/0x80 [ 43.695901] [<ffffffff8150169e>] ? dev_set_rx_mode+0x1e/0x40 [ 43.696180] [<ffffffff8150169e>] dev_set_rx_mode+0x1e/0x40 [ 43.696460] [<ffffffff8150189c>] dev_set_promiscuity+0x3c/0x50 [ 43.696750] [<ffffffffa0586845>] br_port_set_promisc+0x25/0x50 [bridge] [ 43.697052] [<ffffffffa05869aa>] br_manage_promisc+0x8a/0xe0 [bridge] [ 43.697348] [<ffffffffa05826ee>] br_dev_change_rx_flags+0x1e/0x20 [bridge] [ 43.697655] [<ffffffff81501532>] __dev_set_promiscuity+0x132/0x1f0 [ 43.697943] [<ffffffff81501672>] __dev_set_rx_mode+0x82/0x90 [ 43.698223] [<ffffffff815072de>] dev_uc_add+0x5e/0x80 [ 43.698498] [<ffffffffa05b3c62>] vlan_device_event+0x542/0x650 [8021q] [ 43.698798] [<ffffffff8109886d>] notifier_call_chain+0x5d/0x80 [ 43.699083] [<ffffffff810988b6>] raw_notifier_call_chain+0x16/0x20 [ 43.699374] [<ffffffff814f456e>] call_netdevice_notifiers_info+0x6e/0x80 [ 43.699678] [<ffffffff814f4596>] call_netdevice_notifiers+0x16/0x20 [ 43.699973] [<ffffffffa05872be>] br_add_if+0x47e/0x4c0 [bridge] [ 43.700259] [<ffffffffa058801e>] add_del_if+0x6e/0x80 [bridge] [ 43.700548] [<ffffffffa0588b5f>] br_dev_ioctl+0xaf/0xc0 [bridge] [ 43.700836] [<ffffffff8151a7ac>] dev_ifsioc+0x30c/0x3c0 [ 43.701106] [<ffffffff8151aac9>] dev_ioctl+0xf9/0x6f0 [ 43.701379] [<ffffffff81254345>] ? mntput_no_expire+0x5/0x450 [ 43.701665] [<ffffffff812543ee>] ? mntput_no_expire+0xae/0x450 [ 43.701947] [<ffffffff814d7b02>] sock_do_ioctl+0x42/0x50 [ 43.702219] [<ffffffff814d8175>] sock_ioctl+0x1e5/0x290 [ 43.702500] [<ffffffff81242d0b>] do_vfs_ioctl+0x2cb/0x5c0 [ 43.702771] [<ffffffff81243079>] SyS_ioctl+0x79/0x90 [ 43.703033] [<ffffffff815eebb6>] entry_SYSCALL_64_fastpath+0x16/0x7a CC: Vlad Yasevich <vyasevic@redhat.com> CC: Stephen Hemminger <stephen@networkplumber.org> CC: Bridge list <bridge@lists.linux-foundation.org> CC: Andy Gospodarek <gospo@cumulusnetworks.com> CC: Roopa Prabhu <roopa@cumulusnetworks.com> Fixes: 2796d0c648c9 ("bridge: Automatically manage port promiscuous mode.") Reported-by: Andy Gospodarek <gospo@cumulusnetworks.com> Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-31ipv6: update skb->csum when CE mark is propagatedEric Dumazet
[ Upstream commit 34ae6a1aa0540f0f781dd265366036355fdc8930 ] When a tunnel decapsulates the outer header, it has to comply with RFC 6080 and eventually propagate CE mark into inner header. It turns out IP6_ECN_set_ce() does not correctly update skb->csum for CHECKSUM_COMPLETE packets, triggering infamous "hw csum failure" messages and stack traces. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-31net: bpf: reject invalid shiftsRabin Vincent
[ Upstream commit 229394e8e62a4191d592842cf67e80c62a492937 ] On ARM64, a BUG() is triggered in the eBPF JIT if a filter with a constant shift that can't be encoded in the immediate field of the UBFM/SBFM instructions is passed to the JIT. Since these shifts amounts, which are negative or >= regsize, are invalid, reject them in the eBPF verifier and the classic BPF filter checker, for all architectures. Signed-off-by: Rabin Vincent <rabin@rab.in> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-31phonet: properly unshare skbs in phonet_rcv()Eric Dumazet
[ Upstream commit 7aaed57c5c2890634cfadf725173c7c68ea4cb4f ] Ivaylo Dimitrov reported a regression caused by commit 7866a621043f ("dev: add per net_device packet type chains"). skb->dev becomes NULL and we crash in __netif_receive_skb_core(). Before above commit, different kind of bugs or corruptions could happen without major crash. But the root cause is that phonet_rcv() can queue skb without checking if skb is shared or not. Many thanks to Ivaylo Dimitrov for his help, diagnosis and tests. Reported-by: Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com> Tested-by: Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Remi Denis-Courmont <courmisch@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-31net: preserve IP control block during GSO segmentationKonstantin Khlebnikov
[ Upstream commit 9207f9d45b0ad071baa128e846d7e7ed85016df3 ] Skb_gso_segment() uses skb control block during segmentation. This patch adds 32-bytes room for previous control block which will be copied into all resulting segments. This patch fixes kernel crash during fragmenting forwarded packets. Fragmentation requires valid IP CB in skb for clearing ip options. Also patch removes custom save/restore in ovs code, now it's redundant. Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com> Link: http://lkml.kernel.org/r/CALYGNiP-0MZ-FExV2HutTvE9U-QQtkKSoE--KN=JQE5STYsjAA@mail.gmail.com Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-31udp: disallow UFO for sockets with SO_NO_CHECK optionMichal Kubeček
[ Upstream commit 40ba330227ad00b8c0cdf2f425736ff9549cc423 ] Commit acf8dd0a9d0b ("udp: only allow UFO for packets from SOCK_DGRAM sockets") disallows UFO for packets sent from raw sockets. We need to do the same also for SOCK_DGRAM sockets with SO_NO_CHECK options, even if for a bit different reason: while such socket would override the CHECKSUM_PARTIAL set by ip_ufo_append_data(), gso_size is still set and bad offloading flags warning is triggered in __skb_gso_segment(). In the IPv6 case, SO_NO_CHECK option is ignored but we need to disallow UFO for packets sent by sockets with UDP_NO_CHECK6_TX option. Signed-off-by: Michal Kubecek <mkubecek@suse.cz> Tested-by: Shannon Nelson <shannon.nelson@intel.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-31tcp_yeah: don't set ssthresh below 2Neal Cardwell
[ Upstream commit 83d15e70c4d8909d722c0d64747d8fb42e38a48f ] For tcp_yeah, use an ssthresh floor of 2, the same floor used by Reno and CUBIC, per RFC 5681 (equation 4). tcp_yeah_ssthresh() was sometimes returning a 0 or negative ssthresh value if the intended reduction is as big or bigger than the current cwnd. Congestion control modules should never return a zero or negative ssthresh. A zero ssthresh generally results in a zero cwnd, causing the connection to stall. A negative ssthresh value will be interpreted as a u32 and will set a target cwnd for PRR near 4 billion. Oleksandr Natalenko reported that a system using tcp_yeah with ECN could see a warning about a prior_cwnd of 0 in tcp_cwnd_reduction(). Testing verified that this was due to tcp_yeah_ssthresh() misbehaving in this way. Reported-by: Oleksandr Natalenko <oleksandr@natalenko.name> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-31ipv6: tcp: add rcu locking in tcp_v6_send_synack()Eric Dumazet
[ Upstream commit 3e4006f0b86a5ae5eb0e8215f9a9e1db24506977 ] When first SYNACK is sent, we already hold rcu_read_lock(), but this is not true if a SYNACK is retransmitted, as a timer (soft) interrupt does not hold rcu_read_lock() Fixes: 45f6fad84cc30 ("ipv6: add complete rcu protection around np->opt") Reported-by: Dave Jones <davej@codemonkey.org.uk> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-31net: sctp: prevent writes to cookie_hmac_alg from accessing invalid memorySasha Levin
[ Upstream commit 320f1a4a175e7cd5d3f006f92b4d4d3e2cbb7bb5 ] proc_dostring() needs an initialized destination string, while the one provided in proc_sctp_do_hmac_alg() contains stack garbage. Thus, writing to cookie_hmac_alg would strlen() that garbage and end up accessing invalid memory. Fixes: 3c68198e7 ("sctp: Make hmac algorithm selection for cookie generation dynamic") Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-31net: possible use after free in dst_releaseFrancesco Ruggeri
[ Upstream commit 07a5d38453599052aff0877b16bb9c1585f08609 ] dst_release should not access dst->flags after decrementing __refcnt to 0. The dst_entry may be in dst_busy_list and dst_gc_task may dst_destroy it before dst_release gets a chance to access dst->flags. Fixes: d69bbf88c8d0 ("net: fix a race in dst_release()") Fixes: 27b75c95f10d ("net: avoid RCU for NOCACHE dst") Signed-off-by: Francesco Ruggeri <fruggeri@arista.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-31net: sched: fix missing free per cpu on qstatsJohn Fastabend
[ Upstream commit 73c20a8b7245273125cfe92c4b46e6fdb568a801 ] When a qdisc is using per cpu stats (currently just the ingress qdisc) only the bstats are being freed. This also free's the qstats. Fixes: b0ab6f92752b9f9d8 ("net: sched: enable per cpu qstats") Signed-off-by: John Fastabend <john.r.fastabend@intel.com> Acked-by: Eric Dumazet <edumazet@google.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-31bridge: Only call /sbin/bridge-stp for the initial network namespaceHannes Frederic Sowa
[ Upstream commit ff62198553e43cdffa9d539f6165d3e83f8a42bc ] [I stole this patch from Eric Biederman. He wrote:] > There is no defined mechanism to pass network namespace information > into /sbin/bridge-stp therefore don't even try to invoke it except > for bridge devices in the initial network namespace. > > It is possible for unprivileged users to cause /sbin/bridge-stp to be > invoked for any network device name which if /sbin/bridge-stp does not > guard against unreasonable arguments or being invoked twice on the > same network device could cause problems. [Hannes: changed patch using netns_eq] Cc: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-31unix: properly account for FDs passed over unix socketswilly tarreau
[ Upstream commit 712f4aad406bb1ed67f3f98d04c044191f0ff593 ] It is possible for a process to allocate and accumulate far more FDs than the process' limit by sending them over a unix socket then closing them to keep the process' fd count low. This change addresses this problem by keeping track of the number of FDs in flight per user and preventing non-privileged processes from having more FDs in flight than their configured FD limit. Reported-by: socketpair@gmail.com Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Mitigates: CVE-2013-4312 (Linux 2.0+) Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: Willy Tarreau <w@1wt.eu> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-31sctp: sctp should release assoc when sctp_make_abort_user return NULL in ↵Xin Long
sctp_close [ Upstream commit 068d8bd338e855286aea54e70d1c101569284b21 ] In sctp_close, sctp_make_abort_user may return NULL because of memory allocation failure. If this happens, it will bypass any state change and never free the assoc. The assoc has no chance to be freed and it will be kept in memory with the state it had even after the socket is closed by sctp_close(). So if sctp_make_abort_user fails to allocate memory, we should abort the asoc via sctp_primitive_ABORT as well. Just like the annotation in sctp_sf_cookie_wait_prm_abort and sctp_sf_do_9_1_prm_abort said, "Even if we can't send the ABORT due to low memory delete the TCB. This is a departure from our typical NOMEM handling". But then the chunk is NULL (low memory) and the SCTP_CMD_REPLY cmd would dereference the chunk pointer, and system crash. So we should add SCTP_CMD_REPLY cmd only when the chunk is not NULL, just like other places where it adds SCTP_CMD_REPLY cmd. Signed-off-by: Xin Long <lucien.xin@gmail.com> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-31addrconf: always initialize sysctl table dataWANG Cong
[ Upstream commit 5449a5ca9bc27dd51a462de7ca0b1cd861cd2bd0 ] When sysctl performs restrict writes, it allows to write from a middle position of a sysctl file, which requires us to initialize the table data before calling proc_dostring() for the write case. Fixes: 3d1bec99320d ("ipv6: introduce secret_stable to ipv6_devconf") Reported-by: Sasha Levin <sasha.levin@oracle.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Tested-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-31ipv6/addrlabel: fix ip6addrlbl_get()Andrey Ryabinin
[ Upstream commit e459dfeeb64008b2d23bdf600f03b3605dbb8152 ] ip6addrlbl_get() has never worked. If ip6addrlbl_hold() succeeded, ip6addrlbl_get() will exit with '-ESRCH'. If ip6addrlbl_hold() failed, ip6addrlbl_get() will use about to be free ip6addrlbl_entry pointer. Fix this by inverting ip6addrlbl_hold() check. Fixes: 2a8cc6c89039 ("[IPV6] ADDRCONF: Support RFC3484 configurable address selection policy table.") Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Reviewed-by: Cong Wang <cwang@twopensource.com> Acked-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-22tcp: restore fastopen with no data in SYN packetEric Dumazet
[ Upstream commit 07e100f984975cb0417a7d5e626d0409efbad478 ] Yuchung tracked a regression caused by commit 57be5bdad759 ("ip: convert tcp_sendmsg() to iov_iter primitives") for TCP Fast Open. Some Fast Open users do not actually add any data in the SYN packet. Fixes: 57be5bdad759 ("ip: convert tcp_sendmsg() to iov_iter primitives") Reported-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-22af_unix: Revert 'lock_interruptible' in stream receive codeRainer Weikusat
[ Upstream commit 3822b5c2fc62e3de8a0f33806ff279fb7df92432 ] With b3ca9b02b00704053a38bfe4c31dbbb9c13595d0, the AF_UNIX SOCK_STREAM receive code was changed from using mutex_lock(&u->readlock) to mutex_lock_interruptible(&u->readlock) to prevent signals from being delayed for an indefinite time if a thread sleeping on the mutex happened to be selected for handling the signal. But this was never a problem with the stream receive code (as opposed to its datagram counterpart) as that never went to sleep waiting for new messages with the mutex held and thus, wouldn't cause secondary readers to block on the mutex waiting for the sleeping primary reader. As the interruptible locking makes the code more complicated in exchange for no benefit, change it back to using mutex_lock. Signed-off-by: Rainer Weikusat <rweikusat@mobileactivedefense.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-22fou: clean up socket with kfree_rcuHannes Frederic Sowa
[ Upstream commit 3036facbb7be3a169e35be3b271162b0fa564a2d ] fou->udp_offloads is managed by RCU. As it is actually included inside the fou sockets, we cannot let the memory go out of scope before a grace period. We either can synchronize_rcu or switch over to kfree_rcu to manage the sockets. kfree_rcu seems appropriate as it is used by vxlan and geneve. Fixes: 23461551c00628c ("fou: Support for foo-over-udp RX path") Cc: Tom Herbert <tom@herbertland.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-22ipv6: automatically enable stable privacy mode if stable_secret setHannes Frederic Sowa
[ Upstream commit 9b29c6962b70f232cde4076b1020191e1be0889d ] Bjørn reported that while we switch all interfaces to privacy stable mode when setting the secret, we don't set this mode for new interfaces. This does not make sense, so change this behaviour. Fixes: 622c81d57b392cc ("ipv6: generation of stable privacy addresses for link-local and autoconf") Reported-by: Bjørn Mork <bjorn@mork.no> Cc: Bjørn Mork <bjorn@mork.no> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-22net: fix uninitialized variable issuetadeusz.struk@intel.com
[ Upstream commit 130ed5d105dde141e7fe60d5440aa53e0a84f13b ] msg_iocb needs to be initialized on the recv/recvfrom path. Otherwise afalg will wrongly interpret it as an async call. Cc: stable@vger.kernel.org Reported-by: Harald Freudenberger <freude@linux.vnet.ibm.com> Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-22bluetooth: Validate socket address length in sco_sock_bind().David S. Miller
[ Upstream commit 5233252fce714053f0151680933571a2da9cbfb4 ] Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-22net_sched: make qdisc_tree_decrease_qlen() work for non mqEric Dumazet
[ Upstream commit 225734de70cd0a9e0b978f3583a4a87939271d5e ] Stas Nichiporovich reported a regression in his HFSC qdisc setup on a non multi queue device. It turns out I mistakenly added a TCQ_F_NOPARENT flag on all qdisc allocated in qdisc_create() for non multi queue devices, which was rather buggy. I was clearly mislead by the TCQ_F_ONETXQUEUE that is also set here for no good reason, since it only matters for the root qdisc. Fixes: 4eaf3b84f288 ("net_sched: fix qdisc_tree_decrease_qlen() races") Reported-by: Stas Nichiporovich <stasn77@gmail.com> Tested-by: Stas Nichiporovich <stasn77@gmail.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-22net: check both type and procotol for tcp socketsWANG Cong
[ Upstream commit ac5cc977991d2dce85fc734a6c71ddb33f6fe3c1 ] Dmitry reported the following out-of-bound access: Call Trace: [<ffffffff816cec2e>] __asan_report_load4_noabort+0x3e/0x40 mm/kasan/report.c:294 [<ffffffff84affb14>] sock_setsockopt+0x1284/0x13d0 net/core/sock.c:880 [< inline >] SYSC_setsockopt net/socket.c:1746 [<ffffffff84aed7ee>] SyS_setsockopt+0x1fe/0x240 net/socket.c:1729 [<ffffffff85c18c76>] entry_SYSCALL_64_fastpath+0x16/0x7a arch/x86/entry/entry_64.S:185 This is because we mistake a raw socket as a tcp socket. We should check both sk->sk_type and sk->sk_protocol to ensure it is a tcp socket. Willem points out __skb_complete_tx_timestamp() needs to fix as well. Reported-by: Dmitry Vyukov <dvyukov@google.com> Cc: Willem de Bruijn <willemdebruijn.kernel@gmail.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-22skbuff: Fix offset error in skb_reorder_vlan_headerVlad Yasevich
[ Upstream commit f654861569872d10dcb79d9d7ca219b316f94ff0 ] skb_reorder_vlan_header is called after the vlan header has been pulled. As a result the offset of the begining of the mac header has been incrased by 4 bytes (VLAN_HLEN). When moving the mac addresses, include this incrase in the offset calcualation so that the mac addresses are copied correctly. Fixes: a6e18ff1117 (vlan: Fix untag operations of stacked vlans with REORDER_HEADER off) CC: Nicolas Dichtel <nicolas.dichtel@6wind.com> CC: Patrick McHardy <kaber@trash.net> Signed-off-by: Vladislav Yasevich <vyasevich@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-22vlan: Fix untag operations of stacked vlans with REORDER_HEADER offVlad Yasevich
[ Upstream commit a6e18ff111701b4ff6947605bfbe9594ec42a6e8 ] When we have multiple stacked vlan devices all of which have turned off REORDER_HEADER flag, the untag operation does not locate the ethernet addresses correctly for nested vlans. The reason is that in case of REORDER_HEADER flag being off, the outer vlan headers are put back and the mac_len is adjusted to account for the presense of the header. Then, the subsequent untag operation, for the next level vlan, always use VLAN_ETH_HLEN to locate the begining of the ethernet header and that ends up being a multiple of 4 bytes short of the actuall beginning of the mac header (the multiple depending on the how many vlan encapsulations ethere are). As a reslult, if there are multiple levles of vlan devices with REODER_HEADER being off, the recevied packets end up being dropped. To solve this, we use skb->mac_len as the offset. The value is always set on receive path and starts out as a ETH_HLEN. The value is also updated when the vlan header manupations occur so we know it will be correct. Signed-off-by: Vladislav Yasevich <vyasevic@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-22net: fix IP early demux racesEric Dumazet
[ Upstream commit 5037e9ef9454917b047f9f3a19b4dd179fbf7cd4 ] David Wilder reported crashes caused by dst reuse. <quote David> I am seeing a crash on a distro V4.2.3 kernel caused by a double release of a dst_entry. In ipv4_dst_destroy() the call to list_empty() finds a poisoned next pointer, indicating the dst_entry has already been removed from the list and freed. The crash occurs 18 to 24 hours into a run of a network stress exerciser. </quote> Thanks to his detailed report and analysis, we were able to understand the core issue. IP early demux can associate a dst to skb, after a lookup in TCP/UDP sockets. When socket cache is not properly set, we want to store into sk->sk_dst_cache the dst for future IP early demux lookups, by acquiring a stable refcount on the dst. Problem is this acquisition is simply using an atomic_inc(), which works well, unless the dst was queued for destruction from dst_release() noticing dst refcount went to zero, if DST_NOCACHE was set on dst. We need to make sure current refcount is not zero before incrementing it, or risk double free as David reported. This patch, being a stable candidate, adds two new helpers, and use them only from IP early demux problematic paths. It might be possible to merge in net-next skb_dst_force() and skb_dst_force_safe(), but I prefer having the smallest patch for stable kernels : Maybe some skb_dst_force() callers do not expect skb->dst can suddenly be cleared. Can probably be backported back to linux-3.6 kernels Reported-by: David J. Wilder <dwilder@us.ibm.com> Tested-by: David J. Wilder <dwilder@us.ibm.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-22net: add validation for the socket syscall protocol argumentHannes Frederic Sowa
[ Upstream commit 79462ad02e861803b3840cc782248c7359451cd9 ] 郭永刚 reported that one could simply crash the kernel as root by using a simple program: int socket_fd; struct sockaddr_in addr; addr.sin_port = 0; addr.sin_addr.s_addr = INADDR_ANY; addr.sin_family = 10; socket_fd = socket(10,3,0x40000000); connect(socket_fd , &addr,16); AF_INET, AF_INET6 sockets actually only support 8-bit protocol identifiers. inet_sock's skc_protocol field thus is sized accordingly, thus larger protocol identifiers simply cut off the higher bits and store a zero in the protocol fields. This could lead to e.g. NULL function pointer because as a result of the cut off inet_num is zero and we call down to inet_autobind, which is NULL for raw sockets. kernel: Call Trace: kernel: [<ffffffff816db90e>] ? inet_autobind+0x2e/0x70 kernel: [<ffffffff816db9a4>] inet_dgram_connect+0x54/0x80 kernel: [<ffffffff81645069>] SYSC_connect+0xd9/0x110 kernel: [<ffffffff810ac51b>] ? ptrace_notify+0x5b/0x80 kernel: [<ffffffff810236d8>] ? syscall_trace_enter_phase2+0x108/0x200 kernel: [<ffffffff81645e0e>] SyS_connect+0xe/0x10 kernel: [<ffffffff81779515>] tracesys_phase2+0x84/0x89 I found no particular commit which introduced this problem. CVE: CVE-2015-8543 Cc: Cong Wang <cwang@twopensource.com> Reported-by: 郭永刚 <guoyonggang@360.cn> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-22ipv6: sctp: clone options to avoid use after freeEric Dumazet
[ Upstream commit 9470e24f35ab81574da54e69df90c1eb4a96b43f ] SCTP is lacking proper np->opt cloning at accept() time. TCP and DCCP use ipv6_dup_options() helper, do the same in SCTP. We might later factorize this code in a common helper to avoid future mistakes. Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Vlad Yasevich <vyasevich@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-22sctp: also copy sk_tsflags when copying the socketMarcelo Ricardo Leitner
[ Upstream commit 50a5ffb1ef535e3c6989711c51b5d61b543a3b45 ] As we are keeping timestamps on when copying the socket, we also have to copy sk_tsflags. This is needed since b9f40e21ef42 ("net-timestamp: move timestamp flags out of sk_flags"). Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Acked-by: Vlad Yasevich <vyasevich@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-22sctp: update the netstamp_needed counter when copying socketsMarcelo Ricardo Leitner
[ Upstream commit 01ce63c90170283a9855d1db4fe81934dddce648 ] Dmitry Vyukov reported that SCTP was triggering a WARN on socket destroy related to disabling sock timestamp. When SCTP accepts an association or peel one off, it copies sock flags but forgot to call net_enable_timestamp() if a packet timestamping flag was copied, leading to extra calls to net_disable_timestamp() whenever such clones were closed. The fix is to call net_enable_timestamp() whenever we copy a sock with that flag on, like tcp does. Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Acked-by: Vlad Yasevich <vyasevich@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-22sctp: use the same clock as if sock source timestamps were onMarcelo Ricardo Leitner
[ Upstream commit cb5e173ed7c03a0d4630ce68a95a186cce3cc872 ] SCTP echoes a cookie o INIT ACK chunks that contains a timestamp, for detecting stale cookies. This cookie is echoed back to the server by the client and then that timestamp is checked. Thing is, if the listening socket is using packet timestamping, the cookie is encoded with ktime_get() value and checked against ktime_get_real(), as done by __net_timestamp(). The fix is to sctp also use ktime_get_real(), so we can compare bananas with bananas later no matter if packet timestamping was enabled or not. Fixes: 52db882f3fc2 ("net: sctp: migrate cookie life from timeval to ktime") Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Acked-by: Vlad Yasevich <vyasevich@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-22ipv6: keep existing flags when setting IFA_F_OPTIMISTICBjørn Mork
[ Upstream commit 9a1ec4612c9bfc94d4185e3459055a37a685e575 ] Commit 64236f3f3d74 ("ipv6: introduce IFA_F_STABLE_PRIVACY flag") failed to update the setting of the IFA_F_OPTIMISTIC flag, causing the IFA_F_STABLE_PRIVACY flag to be lost if IFA_F_OPTIMISTIC is set. Cc: Erik Kline <ek@google.com> Cc: Fernando Gont <fgont@si6networks.com> Cc: Lorenzo Colitti <lorenzo@google.com> Cc: YOSHIFUJI Hideaki/吉藤英明 <hideaki.yoshifuji@miraclelinux.com> Cc: Hannes Frederic Sowa <hannes@stressinduktion.org> Fixes: 64236f3f3d74 ("ipv6: introduce IFA_F_STABLE_PRIVACY flag") Signed-off-by: Bjørn Mork <bjorn@mork.no> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-22gre6: allow to update all parameters via rtnlNicolas Dichtel
[ Upstream commit 6a61d4dbf4f54b5683e0f1e58d873cecca7cb977 ] Parameters were updated only if the kernel was unable to find the tunnel with the new parameters, ie only if core pamareters were updated (keys, addr, link, type). Now it's possible to update ttl, hoplimit, flowinfo and flags. Fixes: c12b395a4664 ("gre: Support GRE over IPv6") Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-14net_sched: fix qdisc_tree_decrease_qlen() racesEric Dumazet
[ Upstream commit 4eaf3b84f2881c9c028f1d5e76c52ab575fe3a66 ] qdisc_tree_decrease_qlen() suffers from two problems on multiqueue devices. One problem is that it updates sch->q.qlen and sch->qstats.drops on the mq/mqprio root qdisc, while it should not : Daniele reported underflows errors : [ 681.774821] PAX: sch->q.qlen: 0 n: 1 [ 681.774825] PAX: size overflow detected in function qdisc_tree_decrease_qlen net/sched/sch_api.c:769 cicus.693_49 min, count: 72, decl: qlen; num: 0; context: sk_buff_head; [ 681.774954] CPU: 2 PID: 19 Comm: ksoftirqd/2 Tainted: G O 4.2.6.201511282239-1-grsec #1 [ 681.774955] Hardware name: ASUSTeK COMPUTER INC. X302LJ/X302LJ, BIOS X302LJ.202 03/05/2015 [ 681.774956] ffffffffa9a04863 0000000000000000 0000000000000000 ffffffffa990ff7c [ 681.774959] ffffc90000d3bc38 ffffffffa95d2810 0000000000000007 ffffffffa991002b [ 681.774960] ffffc90000d3bc68 ffffffffa91a44f4 0000000000000001 0000000000000001 [ 681.774962] Call Trace: [ 681.774967] [<ffffffffa95d2810>] dump_stack+0x4c/0x7f [ 681.774970] [<ffffffffa91a44f4>] report_size_overflow+0x34/0x50 [ 681.774972] [<ffffffffa94d17e2>] qdisc_tree_decrease_qlen+0x152/0x160 [ 681.774976] [<ffffffffc02694b1>] fq_codel_dequeue+0x7b1/0x820 [sch_fq_codel] [ 681.774978] [<ffffffffc02680a0>] ? qdisc_peek_dequeued+0xa0/0xa0 [sch_fq_codel] [ 681.774980] [<ffffffffa94cd92d>] __qdisc_run+0x4d/0x1d0 [ 681.774983] [<ffffffffa949b2b2>] net_tx_action+0xc2/0x160 [ 681.774985] [<ffffffffa90664c1>] __do_softirq+0xf1/0x200 [ 681.774987] [<ffffffffa90665ee>] run_ksoftirqd+0x1e/0x30 [ 681.774989] [<ffffffffa90896b0>] smpboot_thread_fn+0x150/0x260 [ 681.774991] [<ffffffffa9089560>] ? sort_range+0x40/0x40 [ 681.774992] [<ffffffffa9085fe4>] kthread+0xe4/0x100 [ 681.774994] [<ffffffffa9085f00>] ? kthread_worker_fn+0x170/0x170 [ 681.774995] [<ffffffffa95d8d1e>] ret_from_fork+0x3e/0x70 mq/mqprio have their own ways to report qlen/drops by folding stats on all their queues, with appropriate locking. A second problem is that qdisc_tree_decrease_qlen() calls qdisc_lookup() without proper locking : concurrent qdisc updates could corrupt the list that qdisc_match_from_root() parses to find a qdisc given its handle. Fix first problem adding a TCQ_F_NOPARENT qdisc flag that qdisc_tree_decrease_qlen() can use to abort its tree traversal, as soon as it meets a mq/mqprio qdisc children. Second problem can be fixed by RCU protection. Qdisc are already freed after RCU grace period, so qdisc_list_add() and qdisc_list_del() simply have to use appropriate rcu list variants. A future patch will add a per struct netdev_queue list anchor, so that qdisc_tree_decrease_qlen() can have more efficient lookups. Reported-by: Daniele Fucini <dfucini@gmail.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Cong Wang <cwang@twopensource.com> Cc: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-14ipv6: sctp: implement sctp_v6_destroy_sock()Eric Dumazet
[ Upstream commit 602dd62dfbda3e63a2d6a3cbde953ebe82bf5087 ] Dmitry Vyukov reported a memory leak using IPV6 SCTP sockets. We need to call inet6_destroy_sock() to properly release inet6 specific fields. Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-14net/neighbour: fix crash at dumping device-agnostic proxy entriesKonstantin Khlebnikov
[ Upstream commit 6adc5fd6a142c6e2c80574c1db0c7c17dedaa42e ] Proxy entries could have null pointer to net-device. Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com> Fixes: 84920c1420e2 ("net: Allow ipv6 proxies and arp proxies be shown with iproute2") Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-14ipv6: add complete rcu protection around np->optEric Dumazet
[ Upstream commit 45f6fad84cc305103b28d73482b344d7f5b76f39 ] This patch addresses multiple problems : UDP/RAW sendmsg() need to get a stable struct ipv6_txoptions while socket is not locked : Other threads can change np->opt concurrently. Dmitry posted a syzkaller (http://github.com/google/syzkaller) program desmonstrating use-after-free. Starting with TCP/DCCP lockless listeners, tcp_v6_syn_recv_sock() and dccp_v6_request_recv_sock() also need to use RCU protection to dereference np->opt once (before calling ipv6_dup_options()) This patch adds full RCU protection to np->opt Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-14RDS: fix race condition when sending a message on unbound socketQuentin Casasnovas
[ Upstream commit 8c7188b23474cca017b3ef354c4a58456f68303a ] Sasha's found a NULL pointer dereference in the RDS connection code when sending a message to an apparently unbound socket. The problem is caused by the code checking if the socket is bound in rds_sendmsg(), which checks the rs_bound_addr field without taking a lock on the socket. This opens a race where rs_bound_addr is temporarily set but where the transport is not in rds_bind(), leading to a NULL pointer dereference when trying to dereference 'trans' in __rds_conn_create(). Vegard wrote a reproducer for this issue, so kindly ask him to share if you're interested. I cannot reproduce the NULL pointer dereference using Vegard's reproducer with this patch, whereas I could without. Complete earlier incomplete fix to CVE-2015-6937: 74e98eb08588 ("RDS: verify the underlying transport exists before creating a connection") Cc: David S. Miller <davem@davemloft.net> Cc: stable@vger.kernel.org Reviewed-by: Vegard Nossum <vegard.nossum@oracle.com> Reviewed-by: Sasha Levin <sasha.levin@oracle.com> Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com> Signed-off-by: Quentin Casasnovas <quentin.casasnovas@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-14ipv6: distinguish frag queues by device for multicast and link-local packetsMichal Kubeček
[ Upstream commit 264640fc2c5f4f913db5c73fa3eb1ead2c45e9d7 ] If a fragmented multicast packet is received on an ethernet device which has an active macvlan on top of it, each fragment is duplicated and received both on the underlying device and the macvlan. If some fragments for macvlan are processed before the whole packet for the underlying device is reassembled, the "overlapping fragments" test in ip6_frag_queue() discards the whole fragment queue. To resolve this, add device ifindex to the search key and require it to match reassembling multicast packets and packets to link-local addresses. Note: similar patch has been already submitted by Yoshifuji Hideaki in http://patchwork.ozlabs.org/patch/220979/ but got lost and forgotten for some reason. Signed-off-by: Michal Kubecek <mkubecek@suse.cz> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-14net: ip6mr: fix static mfc/dev leaks on table destructionNikolay Aleksandrov
[ Upstream commit 4c6980462f32b4f282c5d8e5f7ea8070e2937725 ] Similar to ipv4, when destroying an mrt table the static mfc entries and the static devices are kept, which leads to devices that can never be destroyed (because of refcnt taken) and leaked memory. Make sure that everything is cleaned up on netns destruction. Fixes: 8229efdaef1e ("netns: ip6mr: enable namespace support in ipv6 multicast forwarding code") CC: Benjamin Thery <benjamin.thery@bull.net> Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Reviewed-by: Cong Wang <cwang@twopensource.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-14net: ipmr: fix static mfc/dev leaks on table destructionNikolay Aleksandrov
[ Upstream commit 0e615e9601a15efeeb8942cf7cd4dadba0c8c5a7 ] When destroying an mrt table the static mfc entries and the static devices are kept, which leads to devices that can never be destroyed (because of refcnt taken) and leaked memory, for example: unreferenced object 0xffff880034c144c0 (size 192): comm "mfc-broken", pid 4777, jiffies 4320349055 (age 46001.964s) hex dump (first 32 bytes): 98 53 f0 34 00 88 ff ff 98 53 f0 34 00 88 ff ff .S.4.....S.4.... ef 0a 0a 14 01 02 03 04 00 00 00 00 01 00 00 00 ................ backtrace: [<ffffffff815c1b9e>] kmemleak_alloc+0x4e/0xb0 [<ffffffff811ea6e0>] kmem_cache_alloc+0x190/0x300 [<ffffffff815931cb>] ip_mroute_setsockopt+0x5cb/0x910 [<ffffffff8153d575>] do_ip_setsockopt.isra.11+0x105/0xff0 [<ffffffff8153e490>] ip_setsockopt+0x30/0xa0 [<ffffffff81564e13>] raw_setsockopt+0x33/0x90 [<ffffffff814d1e14>] sock_common_setsockopt+0x14/0x20 [<ffffffff814d0b51>] SyS_setsockopt+0x71/0xc0 [<ffffffff815cdbf6>] entry_SYSCALL_64_fastpath+0x16/0x7a [<ffffffffffffffff>] 0xffffffffffffffff Make sure that everything is cleaned on netns destruction. Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Reviewed-by: Cong Wang <cwang@twopensource.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-14net, scm: fix PaX detected msg_controllen overflow in scm_detach_fdsDaniel Borkmann
[ Upstream commit 6900317f5eff0a7070c5936e5383f589e0de7a09 ] David and HacKurx reported a following/similar size overflow triggered in a grsecurity kernel, thanks to PaX's gcc size overflow plugin: (Already fixed in later grsecurity versions by Brad and PaX Team.) [ 1002.296137] PAX: size overflow detected in function scm_detach_fds net/core/scm.c:314 cicus.202_127 min, count: 4, decl: msg_controllen; num: 0; context: msghdr; [ 1002.296145] CPU: 0 PID: 3685 Comm: scm_rights_recv Not tainted 4.2.3-grsec+ #7 [ 1002.296149] Hardware name: Apple Inc. MacBookAir5,1/Mac-66F35F19FE2A0D05, [...] [ 1002.296153] ffffffff81c27366 0000000000000000 ffffffff81c27375 ffffc90007843aa8 [ 1002.296162] ffffffff818129ba 0000000000000000 ffffffff81c27366 ffffc90007843ad8 [ 1002.296169] ffffffff8121f838 fffffffffffffffc fffffffffffffffc ffffc90007843e60 [ 1002.296176] Call Trace: [ 1002.296190] [<ffffffff818129ba>] dump_stack+0x45/0x57 [ 1002.296200] [<ffffffff8121f838>] report_size_overflow+0x38/0x60 [ 1002.296209] [<ffffffff816a979e>] scm_detach_fds+0x2ce/0x300 [ 1002.296220] [<ffffffff81791899>] unix_stream_read_generic+0x609/0x930 [ 1002.296228] [<ffffffff81791c9f>] unix_stream_recvmsg+0x4f/0x60 [ 1002.296236] [<ffffffff8178dc00>] ? unix_set_peek_off+0x50/0x50 [ 1002.296243] [<ffffffff8168fac7>] sock_recvmsg+0x47/0x60 [ 1002.296248] [<ffffffff81691522>] ___sys_recvmsg+0xe2/0x1e0 [ 1002.296257] [<ffffffff81693496>] __sys_recvmsg+0x46/0x80 [ 1002.296263] [<ffffffff816934fc>] SyS_recvmsg+0x2c/0x40 [ 1002.296271] [<ffffffff8181a3ab>] entry_SYSCALL_64_fastpath+0x12/0x85 Further investigation showed that this can happen when an *odd* number of fds are being passed over AF_UNIX sockets. In these cases CMSG_LEN(i * sizeof(int)) and CMSG_SPACE(i * sizeof(int)), where i is the number of successfully passed fds, differ by 4 bytes due to the extra CMSG_ALIGN() padding in CMSG_SPACE() to an 8 byte boundary on 64 bit. The padding is used to align subsequent cmsg headers in the control buffer. When the control buffer passed in from the receiver side *lacks* these 4 bytes (e.g. due to buggy/wrong API usage), then msg->msg_controllen will overflow in scm_detach_fds(): int cmlen = CMSG_LEN(i * sizeof(int)); <--- cmlen w/o tail-padding err = put_user(SOL_SOCKET, &cm->cmsg_level); if (!err) err = put_user(SCM_RIGHTS, &cm->cmsg_type); if (!err) err = put_user(cmlen, &cm->cmsg_len); if (!err) { cmlen = CMSG_SPACE(i * sizeof(int)); <--- cmlen w/ 4 byte extra tail-padding msg->msg_control += cmlen; msg->msg_controllen -= cmlen; <--- iff no tail-padding space here ... } ... wrap-around F.e. it will wrap to a length of 18446744073709551612 bytes in case the receiver passed in msg->msg_controllen of 20 bytes, and the sender properly transferred 1 fd to the receiver, so that its CMSG_LEN results in 20 bytes and CMSG_SPACE in 24 bytes. In case of MSG_CMSG_COMPAT (scm_detach_fds_compat()), I haven't seen an issue in my tests as alignment seems always on 4 byte boundary. Same should be in case of native 32 bit, where we end up with 4 byte boundaries as well. In practice, passing msg->msg_controllen of 20 to recvmsg() while receiving a single fd would mean that on successful return, msg->msg_controllen is being set by the kernel to 24 bytes instead, thus more than the input buffer advertised. It could f.e. become an issue if such application later on zeroes or copies the control buffer based on the returned msg->msg_controllen elsewhere. Maximum number of fds we can send is a hard upper limit SCM_MAX_FD (253). Going over the code, it seems like msg->msg_controllen is not being read after scm_detach_fds() in scm_recv() anymore by the kernel, good! Relevant recvmsg() handler are unix_dgram_recvmsg() (unix_seqpacket_recvmsg()) and unix_stream_recvmsg(). Both return back to their recvmsg() caller, and ___sys_recvmsg() places the updated length, that is, new msg_control - old msg_control pointer into msg->msg_controllen (hence the 24 bytes seen in the example). Long time ago, Wei Yongjun fixed something related in commit 1ac70e7ad24a ("[NET]: Fix function put_cmsg() which may cause usr application memory overflow"). RFC3542, section 20.2. says: The fields shown as "XX" are possible padding, between the cmsghdr structure and the data, and between the data and the next cmsghdr structure, if required by the implementation. While sending an application may or may not include padding at the end of last ancillary data in msg_controllen and implementations must accept both as valid. On receiving a portable application must provide space for padding at the end of the last ancillary data as implementations may copy out the padding at the end of the control message buffer and include it in the received msg_controllen. When recvmsg() is called if msg_controllen is too small for all the ancillary data items including any trailing padding after the last item an implementation may set MSG_CTRUNC. Since we didn't place MSG_CTRUNC for already quite a long time, just do the same as in 1ac70e7ad24a to avoid an overflow. Btw, even man-page author got this wrong :/ See db939c9b26e9 ("cmsg.3: Fix error in SCM_RIGHTS code sample"). Some people must have copied this (?), thus it got triggered in the wild (reported several times during boot by David and HacKurx). No Fixes tag this time as pre 2002 (that is, pre history tree). Reported-by: David Sterba <dave@jikos.cz> Reported-by: HacKurx <hackurx@gmail.com> Cc: PaX Team <pageexec@freemail.hu> Cc: Emese Revfy <re.emese@gmail.com> Cc: Brad Spengler <spender@grsecurity.net> Cc: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Cc: Eric Dumazet <edumazet@google.com> Reviewed-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-14tcp: initialize tp->copied_seq in case of cross SYN connectionEric Dumazet
[ Upstream commit 142a2e7ece8d8ac0e818eb2c91f99ca894730e2a ] Dmitry provided a syzkaller (http://github.com/google/syzkaller) generated program that triggers the WARNING at net/ipv4/tcp.c:1729 in tcp_recvmsg() : WARN_ON(tp->copied_seq != tp->rcv_nxt && !(flags & (MSG_PEEK | MSG_TRUNC))); His program is specifically attempting a Cross SYN TCP exchange, that we support (for the pleasure of hackers ?), but it looks we lack proper tcp->copied_seq initialization. Thanks again Dmitry for your report and testings. Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Dmitry Vyukov <dvyukov@google.com> Tested-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-14tcp: fix potential huge kmalloc() calls in TCP_REPAIREric Dumazet
[ Upstream commit 5d4c9bfbabdb1d497f21afd81501e5c54b0c85d9 ] tcp_send_rcvq() is used for re-injecting data into tcp receive queue. Problems : - No check against size is performed, allowed user to fool kernel in attempting very large memory allocations, eventually triggering OOM when memory is fragmented. - In case of fault during the copy we do not return correct errno. Lets use alloc_skb_with_frags() to cook optimal skbs. Fixes: 292e8d8c8538 ("tcp: Move rcvq sending to tcp_input.c") Fixes: c0e88ff0f256 ("tcp: Repair socket queues") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Pavel Emelyanov <xemul@parallels.com> Acked-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-14tcp: disable Fast Open on timeouts after handshakeYuchung Cheng
[ Upstream commit 0e45f4da5981895e885dd72fe912a3f8e32bae73 ] Some middle-boxes black-hole the data after the Fast Open handshake (https://www.ietf.org/proceedings/94/slides/slides-94-tcpm-13.pdf). The exact reason is unknown. The work-around is to disable Fast Open temporarily after multiple recurring timeouts with few or no data delivered in the established state. Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Christoph Paasch <cpaasch@apple.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-14tcp: md5: fix lockdep annotationEric Dumazet
[ Upstream commit 1b8e6a01e19f001e9f93b39c32387961c91ed3cc ] When a passive TCP is created, we eventually call tcp_md5_do_add() with sk pointing to the child. It is not owner by the user yet (we will add this socket into listener accept queue a bit later anyway) But we do own the spinlock, so amend the lockdep annotation to avoid following splat : [ 8451.090932] net/ipv4/tcp_ipv4.c:923 suspicious rcu_dereference_protected() usage! [ 8451.090932] [ 8451.090932] other info that might help us debug this: [ 8451.090932] [ 8451.090934] [ 8451.090934] rcu_scheduler_active = 1, debug_locks = 1 [ 8451.090936] 3 locks held by socket_sockopt_/214795: [ 8451.090936] #0: (rcu_read_lock){.+.+..}, at: [<ffffffff855c6ac1>] __netif_receive_skb_core+0x151/0xe90 [ 8451.090947] #1: (rcu_read_lock){.+.+..}, at: [<ffffffff85618143>] ip_local_deliver_finish+0x43/0x2b0 [ 8451.090952] #2: (slock-AF_INET){+.-...}, at: [<ffffffff855acda5>] sk_clone_lock+0x1c5/0x500 [ 8451.090958] [ 8451.090958] stack backtrace: [ 8451.090960] CPU: 7 PID: 214795 Comm: socket_sockopt_ [ 8451.091215] Call Trace: [ 8451.091216] <IRQ> [<ffffffff856fb29c>] dump_stack+0x55/0x76 [ 8451.091229] [<ffffffff85123b5b>] lockdep_rcu_suspicious+0xeb/0x110 [ 8451.091235] [<ffffffff8564544f>] tcp_md5_do_add+0x1bf/0x1e0 [ 8451.091239] [<ffffffff85645751>] tcp_v4_syn_recv_sock+0x1f1/0x4c0 [ 8451.091242] [<ffffffff85642b27>] ? tcp_v4_md5_hash_skb+0x167/0x190 [ 8451.091246] [<ffffffff85647c78>] tcp_check_req+0x3c8/0x500 [ 8451.091249] [<ffffffff856451ae>] ? tcp_v4_inbound_md5_hash+0x11e/0x190 [ 8451.091253] [<ffffffff85647170>] tcp_v4_rcv+0x3c0/0x9f0 [ 8451.091256] [<ffffffff85618143>] ? ip_local_deliver_finish+0x43/0x2b0 [ 8451.091260] [<ffffffff856181b6>] ip_local_deliver_finish+0xb6/0x2b0 [ 8451.091263] [<ffffffff85618143>] ? ip_local_deliver_finish+0x43/0x2b0 [ 8451.091267] [<ffffffff85618d38>] ip_local_deliver+0x48/0x80 [ 8451.091270] [<ffffffff85618510>] ip_rcv_finish+0x160/0x700 [ 8451.091273] [<ffffffff8561900e>] ip_rcv+0x29e/0x3d0 [ 8451.091277] [<ffffffff855c74b7>] __netif_receive_skb_core+0xb47/0xe90 Fixes: a8afca0329988 ("tcp: md5: protects md5sig_info with RCU") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>