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2014-02-15radiotap: fix bitmap-end-finding buffer overrunJohannes Berg
commit bd02cd2549cfcdfc57cb5ce57ffc3feb94f70575 upstream. Evan Huus found (by fuzzing in wireshark) that the radiotap iterator code can access beyond the length of the buffer if the first bitmap claims an extension but then there's no data at all. Fix this. Reported-by: Evan Huus <eapache@gmail.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-02-15net: avoid reference counter overflows on fib_rules in multicast forwardingHannes Frederic Sowa
[ Upstream commit 95f4a45de1a0f172b35451fc52283290adb21f6e ] Bob Falken reported that after 4G packets, multicast forwarding stopped working. This was because of a rule reference counter overflow which freed the rule as soon as the overflow happend. This patch solves this by adding the FIB_LOOKUP_NOREF flag to fib_rules_lookup calls. This is safe even from non-rcu locked sections as in this case the flag only implies not taking a reference to the rule, which we don't need at all. Rules only hold references to the namespace, which are guaranteed to be available during the call of the non-rcu protected function reg_vif_xmit because of the interface reference which itself holds a reference to the net namespace. Fixes: f0ad0860d01e47 ("ipv4: ipmr: support multiple tables") Fixes: d1db275dd3f6e4 ("ipv6: ip6mr: support multiple tables") Reported-by: Bob Falken <NetFestivalHaveFun@gmx.com> Cc: Patrick McHardy <kaber@trash.net> Cc: Thomas Graf <tgraf@suug.ch> Cc: Julian Anastasov <ja@ssi.bg> Cc: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-02-15inet_diag: fix inet_diag_dump_icsk() timewait socket state logicNeal Cardwell
[ Based upon upstream commit 70315d22d3c7383f9a508d0aab21e2eb35b2303a ] Fix inet_diag_dump_icsk() to reflect the fact that both TIME_WAIT and FIN_WAIT2 connections are represented by inet_timewait_sock (not just TIME_WAIT). Thus: (a) We need to iterate through the time_wait buckets if the user wants either TIME_WAIT or FIN_WAIT2. (Before fixing this, "ss -nemoi state fin-wait-2" would not return any sockets, even if there were some in FIN_WAIT2.) (b) We need to check tw_substate to see if the user wants to dump sockets in the particular substate (TIME_WAIT or FIN_WAIT2) that a given connection is in. (Before fixing this, "ss -nemoi state time-wait" would actually return sockets in state FIN_WAIT2.) An analogous fix is in v3.13: 70315d22d3c7383f9a508d0aab21e2eb35b2303a ("inet_diag: fix inet_diag_dump_icsk() to use correct state for timewait sockets") but that patch is quite different because 3.13 code is very different in this area due to the unification of TCP hash tables in 05dbc7b ("tcp/dccp: remove twchain") in v3.13-rc1. I tested that this applies cleanly between v3.3 and v3.12, and tested that it works in both 3.3 and 3.12. It does not apply cleanly to 3.2 and earlier (though it makes semantic sense), and semantically is not the right fix for 3.13 and beyond (as mentioned above). Signed-off-by: Neal Cardwell <ncardwell@google.com> Cc: Eric Dumazet <edumazet@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-02-15bridge: use spin_lock_bh() in br_multicast_set_hash_maxCurt Brune
[ Upstream commit fe0d692bbc645786bce1a98439e548ae619269f5 ] br_multicast_set_hash_max() is called from process context in net/bridge/br_sysfs_br.c by the sysfs store_hash_max() function. br_multicast_set_hash_max() calls spin_lock(&br->multicast_lock), which can deadlock the CPU if a softirq that also tries to take the same lock interrupts br_multicast_set_hash_max() while the lock is held . This can happen quite easily when any of the bridge multicast timers expire, which try to take the same lock. The fix here is to use spin_lock_bh(), preventing other softirqs from executing on this CPU. Steps to reproduce: 1. Create a bridge with several interfaces (I used 4). 2. Set the "multicast query interval" to a low number, like 2. 3. Enable the bridge as a multicast querier. 4. Repeatedly set the bridge hash_max parameter via sysfs. # brctl addbr br0 # brctl addif br0 eth1 eth2 eth3 eth4 # brctl setmcqi br0 2 # brctl setmcquerier br0 1 # while true ; do echo 4096 > /sys/class/net/br0/bridge/hash_max; done Signed-off-by: Curt Brune <curt@cumulusnetworks.com> Signed-off-by: Scott Feldman <sfeldma@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-02-15net: llc: fix use after free in llc_ui_recvmsgDaniel Borkmann
[ Upstream commit 4d231b76eef6c4a6bd9c96769e191517765942cb ] While commit 30a584d944fb fixes datagram interface in LLC, a use after free bug has been introduced for SOCK_STREAM sockets that do not make use of MSG_PEEK. The flow is as follow ... if (!(flags & MSG_PEEK)) { ... sk_eat_skb(sk, skb, false); ... } ... if (used + offset < skb->len) continue; ... where sk_eat_skb() calls __kfree_skb(). Therefore, cache original length and work on skb_len to check partial reads. Fixes: 30a584d944fb ("[LLX]: SOCK_DGRAM interface fixes") Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Cc: Stephen Hemminger <stephen@networkplumber.org> Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-02-15vlan: Fix header ops passthru when doing TX VLAN offload.David S. Miller
[ Upstream commit 2205369a314e12fcec4781cc73ac9c08fc2b47de ] When the vlan code detects that the real device can do TX VLAN offloads in hardware, it tries to arrange for the real device's header_ops to be invoked directly. But it does so illegally, by simply hooking the real device's header_ops up to the VLAN device. This doesn't work because we will end up invoking a set of header_ops routines which expect a device type which matches the real device, but will see a VLAN device instead. Fix this by providing a pass-thru set of header_ops which will arrange to pass the proper real device instead. To facilitate this add a dev_rebuild_header(). There are implementations which provide a ->cache and ->create but not a ->rebuild (f.e. PLIP). So we need a helper function just like dev_hard_header() to avoid crashes. Use this helper in the one existing place where the header_ops->rebuild was being invoked, the neighbour code. With lots of help from Florian Westphal. Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-02-15net: rose: restore old recvmsg behaviorFlorian Westphal
[ Upstream commit f81152e35001e91997ec74a7b4e040e6ab0acccf ] recvmsg handler in net/rose/af_rose.c performs size-check ->msg_namelen. After commit f3d3342602f8bcbf37d7c46641cb9bca7618eb1c (net: rework recvmsg handler msg_name and msg_namelen logic), we now always take the else branch due to namelen being initialized to 0. Digging in netdev-vger-cvs git repo shows that msg_namelen was initialized with a fixed-size since at least 1995, so the else branch was never taken. Compile tested only. Signed-off-by: Florian Westphal <fw@strlen.de> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-02-15rds: prevent dereference of a NULL deviceSasha Levin
[ Upstream commit c2349758acf1874e4c2b93fe41d072336f1a31d0 ] Binding might result in a NULL device, which is dereferenced causing this BUG: [ 1317.260548] BUG: unable to handle kernel NULL pointer dereference at 000000000000097 4 [ 1317.261847] IP: [<ffffffff84225f52>] rds_ib_laddr_check+0x82/0x110 [ 1317.263315] PGD 418bcb067 PUD 3ceb21067 PMD 0 [ 1317.263502] Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC [ 1317.264179] Dumping ftrace buffer: [ 1317.264774] (ftrace buffer empty) [ 1317.265220] Modules linked in: [ 1317.265824] CPU: 4 PID: 836 Comm: trinity-child46 Tainted: G W 3.13.0-rc4- next-20131218-sasha-00013-g2cebb9b-dirty #4159 [ 1317.267415] task: ffff8803ddf33000 ti: ffff8803cd31a000 task.ti: ffff8803cd31a000 [ 1317.268399] RIP: 0010:[<ffffffff84225f52>] [<ffffffff84225f52>] rds_ib_laddr_check+ 0x82/0x110 [ 1317.269670] RSP: 0000:ffff8803cd31bdf8 EFLAGS: 00010246 [ 1317.270230] RAX: 0000000000000000 RBX: ffff88020b0dd388 RCX: 0000000000000000 [ 1317.270230] RDX: ffffffff8439822e RSI: 00000000000c000a RDI: 0000000000000286 [ 1317.270230] RBP: ffff8803cd31be38 R08: 0000000000000000 R09: 0000000000000000 [ 1317.270230] R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000 [ 1317.270230] R13: 0000000054086700 R14: 0000000000a25de0 R15: 0000000000000031 [ 1317.270230] FS: 00007ff40251d700(0000) GS:ffff88022e200000(0000) knlGS:000000000000 0000 [ 1317.270230] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b [ 1317.270230] CR2: 0000000000000974 CR3: 00000003cd478000 CR4: 00000000000006e0 [ 1317.270230] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 1317.270230] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000090602 [ 1317.270230] Stack: [ 1317.270230] 0000000054086700 5408670000a25de0 5408670000000002 0000000000000000 [ 1317.270230] ffffffff84223542 00000000ea54c767 0000000000000000 ffffffff86d26160 [ 1317.270230] ffff8803cd31be68 ffffffff84223556 ffff8803cd31beb8 ffff8800c6765280 [ 1317.270230] Call Trace: [ 1317.270230] [<ffffffff84223542>] ? rds_trans_get_preferred+0x42/0xa0 [ 1317.270230] [<ffffffff84223556>] rds_trans_get_preferred+0x56/0xa0 [ 1317.270230] [<ffffffff8421c9c3>] rds_bind+0x73/0xf0 [ 1317.270230] [<ffffffff83e4ce62>] SYSC_bind+0x92/0xf0 [ 1317.270230] [<ffffffff812493f8>] ? context_tracking_user_exit+0xb8/0x1d0 [ 1317.270230] [<ffffffff8119313d>] ? trace_hardirqs_on+0xd/0x10 [ 1317.270230] [<ffffffff8107a852>] ? syscall_trace_enter+0x32/0x290 [ 1317.270230] [<ffffffff83e4cece>] SyS_bind+0xe/0x10 [ 1317.270230] [<ffffffff843a6ad0>] tracesys+0xdd/0xe2 [ 1317.270230] Code: 00 8b 45 cc 48 8d 75 d0 48 c7 45 d8 00 00 00 00 66 c7 45 d0 02 00 89 45 d4 48 89 df e8 78 49 76 ff 41 89 c4 85 c0 75 0c 48 8b 03 <80> b8 74 09 00 00 01 7 4 06 41 bc 9d ff ff ff f6 05 2a b6 c2 02 [ 1317.270230] RIP [<ffffffff84225f52>] rds_ib_laddr_check+0x82/0x110 [ 1317.270230] RSP <ffff8803cd31bdf8> [ 1317.270230] CR2: 0000000000000974 Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-02-15net: inet_diag: zero out uninitialized idiag_{src,dst} fieldsDaniel Borkmann
[ Upstream commit b1aac815c0891fe4a55a6b0b715910142227700f ] Jakub reported while working with nlmon netlink sniffer that parts of the inet_diag_sockid are not initialized when r->idiag_family != AF_INET6. That is, fields of r->id.idiag_src[1 ... 3], r->id.idiag_dst[1 ... 3]. In fact, it seems that we can leak 6 * sizeof(u32) byte of kernel [slab] memory through this. At least, in udp_dump_one(), we allocate a skb in ... rep = nlmsg_new(sizeof(struct inet_diag_msg) + ..., GFP_KERNEL); ... and then pass that to inet_sk_diag_fill() that puts the whole struct inet_diag_msg into the skb, where we only fill out r->id.idiag_src[0], r->id.idiag_dst[0] and leave the rest untouched: r->id.idiag_src[0] = inet->inet_rcv_saddr; r->id.idiag_dst[0] = inet->inet_daddr; struct inet_diag_msg embeds struct inet_diag_sockid that is correctly / fully filled out in IPv6 case, but for IPv4 not. So just zero them out by using plain memset (for this little amount of bytes it's probably not worth the extra check for idiag_family == AF_INET). Similarly, fix also other places where we fill that out. Reported-by: Jakub Zawadzki <darkjames-ws@darkjames.pl> Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-02-15net: unix: allow bind to fail on mutex lockSasha Levin
[ Upstream commit 37ab4fa7844a044dc21fde45e2a0fc2f3c3b6490 ] This is similar to the set_peek_off patch where calling bind while the socket is stuck in unix_dgram_recvmsg() will block and cause a hung task spew after a while. This is also the last place that did a straightforward mutex_lock(), so there shouldn't be any more of these patches. Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-02-15net: drop_monitor: fix the value of maxattrChangli Gao
[ Upstream commit d323e92cc3f4edd943610557c9ea1bb4bb5056e8 ] maxattr in genl_family should be used to save the max attribute type, but not the max command type. Drop monitor doesn't support any attributes, so we should leave it as zero. Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-02-15ipv6: don't count addrconf generated routes against gc limitHannes Frederic Sowa
[ Upstream commit a3300ef4bbb1f1e33ff0400e1e6cf7733d988f4f ] Brett Ciphery reported that new ipv6 addresses failed to get installed because the addrconf generated dsts where counted against the dst gc limit. We don't need to count those routes like we currently don't count administratively added routes. Because the max_addresses check enforces a limit on unbounded address generation first in case someone plays with router advertisments, we are still safe here. Reported-by: Brett Ciphery <brett.ciphery@windriver.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-02-15rds: prevent BUG_ON triggered on congestion update to loopbackVenkat Venkatsubra
[ Upstream commit 18fc25c94eadc52a42c025125af24657a93638c0 ] After congestion update on a local connection, when rds_ib_xmit returns less bytes than that are there in the message, rds_send_xmit calls back rds_ib_xmit with an offset that causes BUG_ON(off & RDS_FRAG_SIZE) to trigger. For a 4Kb PAGE_SIZE rds_ib_xmit returns min(8240,4096)=4096 when actually the message contains 8240 bytes. rds_send_xmit thinks there is more to send and calls rds_ib_xmit again with a data offset "off" of 4096-48(rds header) =4048 bytes thus hitting the BUG_ON(off & RDS_FRAG_SIZE) [RDS_FRAG_SIZE=4k]. The commit 6094628bfd94323fc1cea05ec2c6affd98c18f7f "rds: prevent BUG_ON triggering on congestion map updates" introduced this regression. That change was addressing the triggering of a different BUG_ON in rds_send_xmit() on PowerPC architecture with 64Kbytes PAGE_SIZE: BUG_ON(ret != 0 && conn->c_xmit_sg == rm->data.op_nents); This was the sequence it was going through: (rds_ib_xmit) /* Do not send cong updates to IB loopback */ if (conn->c_loopback && rm->m_inc.i_hdr.h_flags & RDS_FLAG_CONG_BITMAP) { rds_cong_map_updated(conn->c_fcong, ~(u64) 0); return sizeof(struct rds_header) + RDS_CONG_MAP_BYTES; } rds_ib_xmit returns 8240 rds_send_xmit: c_xmit_data_off = 0 + 8240 - 48 (rds header accounted only the first time) = 8192 c_xmit_data_off < 65536 (sg->length), so calls rds_ib_xmit again rds_ib_xmit returns 8240 rds_send_xmit: c_xmit_data_off = 8192 + 8240 = 16432, calls rds_ib_xmit again and so on (c_xmit_data_off 24672,32912,41152,49392,57632) rds_ib_xmit returns 8240 On this iteration this sequence causes the BUG_ON in rds_send_xmit: while (ret) { tmp = min_t(int, ret, sg->length - conn->c_xmit_data_off); [tmp = 65536 - 57632 = 7904] conn->c_xmit_data_off += tmp; [c_xmit_data_off = 57632 + 7904 = 65536] ret -= tmp; [ret = 8240 - 7904 = 336] if (conn->c_xmit_data_off == sg->length) { conn->c_xmit_data_off = 0; sg++; conn->c_xmit_sg++; BUG_ON(ret != 0 && conn->c_xmit_sg == rm->data.op_nents); [c_xmit_sg = 1, rm->data.op_nents = 1] What the current fix does: Since the congestion update over loopback is not actually transmitted as a message, all that rds_ib_xmit needs to do is let the caller think the full message has been transmitted and not return partial bytes. It will return 8240 (RDS_CONG_MAP_BYTES+48) when PAGE_SIZE is 4Kb. And 64Kb+48 when page size is 64Kb. Reported-by: Josh Hunt <joshhunt00@gmail.com> Tested-by: Honggang Li <honli@redhat.com> Acked-by: Bang Nguyen <bang.nguyen@oracle.com> Signed-off-by: Venkat Venkatsubra <venkat.x.venkatsubra@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-01-03net: flow_dissector: fail on evil iph->ihlJason Wang
commit 6f092343855a71e03b8d209815d8c45bf3a27fcd upstream. We don't validate iph->ihl which may lead a dead loop if we meet a IPIP skb whose iph->ihl is zero. Fix this by failing immediately when iph->ihl is evil (less than 5). This issue were introduced by commit ec5efe7946280d1e84603389a1030ccec0a767ae (rps: support IPIP encapsulation). Cc: Eric Dumazet <edumazet@google.com> Cc: Petr Matousek <pmatouse@redhat.com> Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.2: the affected code is in __skb_get_rxhash()] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-01-03{pktgen, xfrm} Update IPv4 header total len and checksum after tranformationfan.du
[ Upstream commit 3868204d6b89ea373a273e760609cb08020beb1a ] commit a553e4a6317b2cfc7659542c10fe43184ffe53da ("[PKTGEN]: IPSEC support") tried to support IPsec ESP transport transformation for pktgen, but acctually this doesn't work at all for two reasons(The orignal transformed packet has bad IPv4 checksum value, as well as wrong auth value, reported by wireshark) - After transpormation, IPv4 header total length needs update, because encrypted payload's length is NOT same as that of plain text. - After transformation, IPv4 checksum needs re-caculate because of payload has been changed. With this patch, armmed pktgen with below cofiguration, Wireshark is able to decrypted ESP packet generated by pktgen without any IPv4 checksum error or auth value error. pgset "flag IPSEC" pgset "flows 1" Signed-off-by: Fan Du <fan.du@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-01-03ipv6: fix possible seqlock deadlock in ip6_finish_output2Hannes Frederic Sowa
[ Upstream commit 7f88c6b23afbd31545c676dea77ba9593a1a14bf ] IPv6 stats are 64 bits and thus are protected with a seqlock. By not disabling bottom-half we could deadlock here if we don't disable bh and a softirq reentrantly updates the same mib. Cc: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-01-03inet: fix possible seqlock deadlocksEric Dumazet
[ Upstream commit f1d8cba61c3c4b1eb88e507249c4cb8d635d9a76 ] In commit c9e9042994d3 ("ipv4: fix possible seqlock deadlock") I left another places where IP_INC_STATS_BH() were improperly used. udp_sendmsg(), ping_v4_sendmsg() and tcp_v4_connect() are called from process context, not from softirq context. This was detected by lockdep seqlock support. Reported-by: jongman heo <jongman.heo@samsung.com> Fixes: 584bdf8cbdf6 ("[IPV4]: Fix "ipOutNoRoutes" counter error for TCP and UDP") Fixes: c319b4d76b9e ("net: ipv4: add IPPROTO_ICMP socket kind") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Hannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-01-03af_packet: block BH in prb_shutdown_retire_blk_timer()Veaceslav Falico
[ Upstream commit ec6f809ff6f19fafba3212f6aff0dda71dfac8e8 ] Currently we're using plain spin_lock() in prb_shutdown_retire_blk_timer(), however the timer might fire right in the middle and thus try to re-aquire the same spinlock, leaving us in a endless loop. To fix that, use the spin_lock_bh() to block it. Fixes: f6fb8f100b80 ("af-packet: TPACKET_V3 flexible buffer implementation.") CC: "David S. Miller" <davem@davemloft.net> CC: Daniel Borkmann <dborkman@redhat.com> CC: Willem de Bruijn <willemb@google.com> CC: Phil Sutter <phil@nwl.cc> CC: Eric Dumazet <edumazet@google.com> Reported-by: Jan Stancek <jstancek@redhat.com> Tested-by: Jan Stancek <jstancek@redhat.com> Signed-off-by: Veaceslav Falico <vfalico@redhat.com> Acked-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-01-03packet: fix use after free race in send path when dev is releasedDaniel Borkmann
[ Upstream commit e40526cb20b5ee53419452e1f03d97092f144418 ] Salam reported a use after free bug in PF_PACKET that occurs when we're sending out frames on a socket bound device and suddenly the net device is being unregistered. It appears that commit 827d9780 introduced a possible race condition between {t,}packet_snd() and packet_notifier(). In the case of a bound socket, packet_notifier() can drop the last reference to the net_device and {t,}packet_snd() might end up suddenly sending a packet over a freed net_device. To avoid reverting 827d9780 and thus introducing a performance regression compared to the current state of things, we decided to hold a cached RCU protected pointer to the net device and maintain it on write side via bind spin_lock protected register_prot_hook() and __unregister_prot_hook() calls. In {t,}packet_snd() path, we access this pointer under rcu_read_lock through packet_cached_dev_get() that holds reference to the device to prevent it from being freed through packet_notifier() while we're in send path. This is okay to do as dev_put()/dev_hold() are per-cpu counters, so this should not be a performance issue. Also, the code simplifies a bit as we don't need need_rls_dev anymore. Fixes: 827d978037d7 ("af-packet: Use existing netdev reference for bound sockets.") Reported-by: Salam Noureddine <noureddine@aristanetworks.com> Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: Salam Noureddine <noureddine@aristanetworks.com> Cc: Ben Greear <greearb@candelatech.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-01-03bridge: flush br's address entry in fdb when remove the bridge devDing Tianhong
[ Upstream commit f873042093c0b418d2351fe142222b625c740149 ] When the following commands are executed: brctl addbr br0 ifconfig br0 hw ether <addr> rmmod bridge The calltrace will occur: [ 563.312114] device eth1 left promiscuous mode [ 563.312188] br0: port 1(eth1) entered disabled state [ 563.468190] kmem_cache_destroy bridge_fdb_cache: Slab cache still has objects [ 563.468197] CPU: 6 PID: 6982 Comm: rmmod Tainted: G O 3.12.0-0.7-default+ #9 [ 563.468199] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2007 [ 563.468200] 0000000000000880 ffff88010f111e98 ffffffff814d1c92 ffff88010f111eb8 [ 563.468204] ffffffff81148efd ffff88010f111eb8 0000000000000000 ffff88010f111ec8 [ 563.468206] ffffffffa062a270 ffff88010f111ed8 ffffffffa063ac76 ffff88010f111f78 [ 563.468209] Call Trace: [ 563.468218] [<ffffffff814d1c92>] dump_stack+0x6a/0x78 [ 563.468234] [<ffffffff81148efd>] kmem_cache_destroy+0xfd/0x100 [ 563.468242] [<ffffffffa062a270>] br_fdb_fini+0x10/0x20 [bridge] [ 563.468247] [<ffffffffa063ac76>] br_deinit+0x4e/0x50 [bridge] [ 563.468254] [<ffffffff810c7dc9>] SyS_delete_module+0x199/0x2b0 [ 563.468259] [<ffffffff814e0922>] system_call_fastpath+0x16/0x1b [ 570.377958] Bridge firewalling registered --------------------------- cut here ------------------------------- The reason is that when the bridge dev's address is changed, the br_fdb_change_mac_address() will add new address in fdb, but when the bridge was removed, the address entry in the fdb did not free, the bridge_fdb_cache still has objects when destroy the cache, Fix this by flushing the bridge address entry when removing the bridge. v2: according to the Toshiaki Makita and Vlad's suggestion, I only delete the vlan0 entry, it still have a leak here if the vlan id is other number, so I need to call fdb_delete_by_port(br, NULL, 1) to flush all entries whose dst is NULL for the bridge. Suggested-by: Toshiaki Makita <toshiaki.makita1@gmail.com> Suggested-by: Vlad Yasevich <vyasevich@gmail.com> Signed-off-by: Ding Tianhong <dingtianhong@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-01-03net: core: Always propagate flag changes to interfacesVlad Yasevich
[ Upstream commit d2615bf450694c1302d86b9cc8a8958edfe4c3a4 ] The following commit: b6c40d68ff6498b7f63ddf97cf0aa818d748dee7 net: only invoke dev->change_rx_flags when device is UP tried to fix a problem with VLAN devices and promiscuouse flag setting. The issue was that VLAN device was setting a flag on an interface that was down, thus resulting in bad promiscuity count. This commit blocked flag propagation to any device that is currently down. A later commit: deede2fabe24e00bd7e246eb81cd5767dc6fcfc7 vlan: Don't propagate flag changes on down interfaces fixed VLAN code to only propagate flags when the VLAN interface is up, thus fixing the same issue as above, only localized to VLAN. The problem we have now is that if we have create a complex stack involving multiple software devices like bridges, bonds, and vlans, then it is possible that the flags would not propagate properly to the physical devices. A simple examle of the scenario is the following: eth0----> bond0 ----> bridge0 ---> vlan50 If bond0 or eth0 happen to be down at the time bond0 is added to the bridge, then eth0 will never have promisc mode set which is currently required for operation as part of the bridge. As a result, packets with vlan50 will be dropped by the interface. The only 2 devices that implement the special flag handling are VLAN and DSA and they both have required code to prevent incorrect flag propagation. As a result we can remove the generic solution introduced in b6c40d68ff6498b7f63ddf97cf0aa818d748dee7 and leave it to the individual devices to decide whether they will block flag propagation or not. Reported-by: Stefan Priebe <s.priebe@profihost.ag> Suggested-by: Veaceslav Falico <vfalico@redhat.com> Signed-off-by: Vlad Yasevich <vyasevic@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-01-03ipv6: fix leaking uninitialized port number of offender sockaddrHannes Frederic Sowa
[ Upstream commit 1fa4c710b6fe7b0aac9907240291b6fe6aafc3b8 ] Offenders don't have port numbers, so set it to 0. Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-01-03net: clamp ->msg_namelen instead of returning an errorDan Carpenter
[ Upstream commit db31c55a6fb245fdbb752a2ca4aefec89afabb06 ] If kmsg->msg_namelen > sizeof(struct sockaddr_storage) then in the original code that would lead to memory corruption in the kernel if you had audit configured. If you didn't have audit configured it was harmless. There are some programs such as beta versions of Ruby which use too large of a buffer and returning an error code breaks them. We should clamp the ->msg_namelen value instead. Fixes: 1661bf364ae9 ("net: heap overflow in __audit_sockaddr()") Reported-by: Eric Wong <normalperson@yhbt.net> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Tested-by: Eric Wong <normalperson@yhbt.net> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-01-03inet: fix addr_len/msg->msg_namelen assignment in recv_error and rxpmtu ↵Hannes Frederic Sowa
functions [ Upstream commit 85fbaa75037d0b6b786ff18658ddf0b4014ce2a4 ] Commit bceaa90240b6019ed73b49965eac7d167610be69 ("inet: prevent leakage of uninitialized memory to user in recv syscalls") conditionally updated addr_len if the msg_name is written to. The recv_error and rxpmtu functions relied on the recvmsg functions to set up addr_len before. As this does not happen any more we have to pass addr_len to those functions as well and set it to the size of the corresponding sockaddr length. This broke traceroute and such. Fixes: bceaa90240b6 ("inet: prevent leakage of uninitialized memory to user in recv syscalls") Reported-by: Brad Spengler <spender@grsecurity.net> Reported-by: Tom Labanowski Cc: mpb <mpb.mail@gmail.com> Cc: David S. Miller <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-01-03net: add BUG_ON if kernel advertises msg_namelen > sizeof(struct ↵Hannes Frederic Sowa
sockaddr_storage) [ Upstream commit 68c6beb373955da0886d8f4f5995b3922ceda4be ] In that case it is probable that kernel code overwrote part of the stack. So we should bail out loudly here. The BUG_ON may be removed in future if we are sure all protocols are conformant. Suggested-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-01-03net: rework recvmsg handler msg_name and msg_namelen logicHannes Frederic Sowa
[ Upstream commit f3d3342602f8bcbf37d7c46641cb9bca7618eb1c ] This patch now always passes msg->msg_namelen as 0. recvmsg handlers must set msg_namelen to the proper size <= sizeof(struct sockaddr_storage) to return msg_name to the user. This prevents numerous uninitialized memory leaks we had in the recvmsg handlers and makes it harder for new code to accidentally leak uninitialized memory. Optimize for the case recvfrom is called with NULL as address. We don't need to copy the address at all, so set it to NULL before invoking the recvmsg handler. We can do so, because all the recvmsg handlers must cope with the case a plain read() is called on them. read() also sets msg_name to NULL. Also document these changes in include/linux/net.h as suggested by David Miller. Changes since RFC: Set msg->msg_name = NULL if user specified a NULL in msg_name but had a non-null msg_namelen in verify_iovec/verify_compat_iovec. This doesn't affect sendto as it would bail out earlier while trying to copy-in the address. It also more naturally reflects the logic by the callers of verify_iovec. With this change in place I could remove " if (!uaddr || msg_sys->msg_namelen == 0) msg->msg_name = NULL ". This change does not alter the user visible error logic as we ignore msg_namelen as long as msg_name is NULL. Also remove two unnecessary curly brackets in ___sys_recvmsg and change comments to netdev style. Cc: David Miller <davem@davemloft.net> Suggested-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-01-03inet: prevent leakage of uninitialized memory to user in recv syscallsHannes Frederic Sowa
[ Upstream commit bceaa90240b6019ed73b49965eac7d167610be69 ] Only update *addr_len when we actually fill in sockaddr, otherwise we can return uninitialized memory from the stack to the caller in the recvfrom, recvmmsg and recvmsg syscalls. Drop the the (addr_len == NULL) checks because we only get called with a valid addr_len pointer either from sock_common_recvmsg or inet_recvmsg. If a blocking read waits on a socket which is concurrently shut down we now return zero and set msg_msgnamelen to 0. Reported-by: mpb <mpb.mail@gmail.com> Suggested-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-01-03ipv4: fix possible seqlock deadlockEric Dumazet
[ Upstream commit c9e9042994d37cbc1ee538c500e9da1bb9d1bcdf ] ip4_datagram_connect() being called from process context, it should use IP_INC_STATS() instead of IP_INC_STATS_BH() otherwise we can deadlock on 32bit arches, or get corruptions of SNMP counters. Fixes: 584bdf8cbdf6 ("[IPV4]: Fix "ipOutNoRoutes" counter error for TCP and UDP") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Dave Jones <davej@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-01-036lowpan: Uncompression of traffic class field was incorrectJukka Rissanen
[ Upstream commit 1188f05497e7bd2f2614b99c54adfbe7413d5749 ] If priority/traffic class field in IPv6 header is set (seen when using ssh), the uncompression sets the TC and Flow fields incorrectly. Example: This is IPv6 header of a sent packet. Note the priority/TC (=1) in the first byte. 00000000: 61 00 00 00 00 2c 06 40 fe 80 00 00 00 00 00 00 00000010: 02 02 72 ff fe c6 42 10 fe 80 00 00 00 00 00 00 00000020: 02 1e ab ff fe 4c 52 57 This gets compressed like this in the sending side 00000000: 72 31 04 06 02 1e ab ff fe 4c 52 57 ec c2 00 16 00000010: aa 2d fe 92 86 4e be c6 .... In the receiving end, the packet gets uncompressed to this IPv6 header 00000000: 60 06 06 02 00 2a 1e 40 fe 80 00 00 00 00 00 00 00000010: 02 02 72 ff fe c6 42 10 fe 80 00 00 00 00 00 00 00000020: ab ff fe 4c 52 57 ec c2 First four bytes are set incorrectly and we have also lost two bytes from destination address. The fix is to switch the case values in switch statement when checking the TC field. Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-01-03ipv6: use rt6_get_dflt_router to get default router in rt6_route_rcvDuan Jiong
[ Upstream commit f104a567e673f382b09542a8dc3500aa689957b4 ] As the rfc 4191 said, the Router Preference and Lifetime values in a ::/0 Route Information Option should override the preference and lifetime values in the Router Advertisement header. But when the kernel deals with a ::/0 Route Information Option, the rt6_get_route_info() always return NULL, that means that overriding will not happen, because those default routers were added without flag RTF_ROUTEINFO in rt6_add_dflt_router(). In order to deal with that condition, we should call rt6_get_dflt_router when the prefix length is 0. Signed-off-by: Duan Jiong <duanj.fnst@cn.fujitsu.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-01-03net: Fix "ip rule delete table 256"Andreas Henriksson
[ Upstream commit 13eb2ab2d33c57ebddc57437a7d341995fc9138c ] When trying to delete a table >= 256 using iproute2 the local table will be deleted. The table id is specified as a netlink attribute when it needs more then 8 bits and iproute2 then sets the table field to RT_TABLE_UNSPEC (0). Preconditions to matching the table id in the rule delete code doesn't seem to take the "table id in netlink attribute" into condition so the frh_get_table helper function never gets to do its job when matching against current rule. Use the helper function twice instead of peaking at the table value directly. Originally reported at: http://bugs.debian.org/724783 Reported-by: Nicolas HICHER <nhicher@avencall.com> Signed-off-by: Andreas Henriksson <andreas@fatal.se> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-01-03net: update consumers of MSG_MORE to recognize MSG_SENDPAGE_NOTLASTShawn Landden
commit d3f7d56a7a4671d395e8af87071068a195257bf6 upstream. Commit 35f9c09fe (tcp: tcp_sendpages() should call tcp_push() once) added an internal flag MSG_SENDPAGE_NOTLAST, similar to MSG_MORE. algif_hash, algif_skcipher, and udp used MSG_MORE from tcp_sendpages() and need to see the new flag as identical to MSG_MORE. This fixes sendfile() on AF_ALG. v3: also fix udp Cc: Tom Herbert <therbert@google.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: David S. Miller <davem@davemloft.net> Reported-and-tested-by: Shawn Landden <shawnlandden@gmail.com> Original-patch: Richard Weinberger <richard@nod.at> Signed-off-by: Shawn Landden <shawn@churchofgit.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-01-03mac80211: don't attempt to reorder multicast framesJohannes Berg
commit 051a41fa4ee14f5c39668f0980973b9a195de560 upstream. Multicast frames can't be transmitted as part of an aggregation session (such a session couldn't even be set up) so don't try to reorder them. Trying to do so would cause the reorder to stop working correctly since multicast QoS frames (as transmitted by the Aruba APs this was found with) would cause sequence number confusion in the buffer. Reported-by: Blaise Gassend <blaise@suitabletech.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2014-01-03SUNRPC: Fix a data corruption issue when retransmitting RPC callsTrond Myklebust
commit a6b31d18b02ff9d7915c5898c9b5ca41a798cd73 upstream. The following scenario can cause silent data corruption when doing NFS writes. It has mainly been observed when doing database writes using O_DIRECT. 1) The RPC client uses sendpage() to do zero-copy of the page data. 2) Due to networking issues, the reply from the server is delayed, and so the RPC client times out. 3) The client issues a second sendpage of the page data as part of an RPC call retransmission. 4) The reply to the first transmission arrives from the server _before_ the client hardware has emptied the TCP socket send buffer. 5) After processing the reply, the RPC state machine rules that the call to be done, and triggers the completion callbacks. 6) The application notices the RPC call is done, and reuses the pages to store something else (e.g. a new write). 7) The client NIC drains the TCP socket send buffer. Since the page data has now changed, it reads a corrupted version of the initial RPC call, and puts it on the wire. This patch fixes the problem in the following manner: The ordering guarantees of TCP ensure that when the server sends a reply, then we know that the _first_ transmission has completed. Using zero-copy in that situation is therefore safe. If a time out occurs, we then send the retransmission using sendmsg() (i.e. no zero-copy), We then know that the socket contains a full copy of the data, and so it will retransmit a faithful reproduction even if the RPC call completes, and the application reuses the O_DIRECT buffer in the meantime. Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2013-11-28wireless: radiotap: fix parsing buffer overrunJohannes Berg
commit f5563318ff1bde15b10e736e97ffce13be08bc1a upstream. When parsing an invalid radiotap header, the parser can overrun the buffer that is passed in because it doesn't correctly check 1) the minimum radiotap header size 2) the space for extended bitmaps The first issue doesn't affect any in-kernel user as they all check the minimum size before calling the radiotap function. The second issue could potentially affect the kernel if an skb is passed in that consists only of the radiotap header with a lot of extended bitmaps that extend past the SKB. In that case a read-only buffer overrun by at most 4 bytes is possible. Fix this by adding the appropriate checks to the parser. Reported-by: Evan Huus <eapache@gmail.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2013-11-28mac80211: correctly close cancelled scansEmmanuel Grumbach
commit a754055a1296fcbe6f32de3a5eaca6efb2fd1865 upstream. __ieee80211_scan_completed is called from a worker. This means that the following flow is possible. * driver calls ieee80211_scan_completed * mac80211 cancels the scan (that is already complete) * __ieee80211_scan_completed runs When scan_work will finally run, it will see that the scan hasn't been aborted and might even trigger another scan on another band. This leads to a situation where cfg80211's scan is not done and no further scan can be issued. Fix this by setting a new flag when a HW scan is being cancelled so that no other scan will be triggered. Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2013-11-28mac80211: update sta->last_rx on acked tx framesFelix Fietkau
commit 0c5b93290b2f3c7a376567c03ae8d385b0e99851 upstream. When clients are idle for too long, hostapd sends nullfunc frames for probing. When those are acked by the client, the idle time needs to be updated. To make this work (and to avoid unnecessary probing), update sta->last_rx whenever an ACK was received for a tx packet. Only do this if the flag IEEE80211_HW_REPORTS_TX_ACK_STATUS is set. Signed-off-by: Felix Fietkau <nbd@openwrt.org> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2013-11-28mac80211: drop spoofed packets in ad-hoc modeFelix Fietkau
commit 6329b8d917adc077caa60c2447385554130853a3 upstream. If an Ad-Hoc node receives packets with the Cell ID or its own MAC address as source address, it hits a WARN_ON in sta_info_insert_check() With many packets, this can massively spam the logs. One way that this can easily happen is through having Cisco APs in the area with rouge AP detection and countermeasures enabled. Such Cisco APs will regularly send fake beacons, disassoc and deauth packets that trigger these warnings. To fix this issue, drop such spoofed packets early in the rx path. Reported-by: Thomas Huehn <thomas@net.t-labs.tu-berlin.de> Signed-off-by: Felix Fietkau <nbd@openwrt.org> Signed-off-by: Johannes Berg <johannes.berg@intel.com> [bwh: Backported to 3.2: use compare_ether_addr() instead of ether_addr_equal()] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2013-11-28netfilter: nf_ct_sip: don't drop packets with offsets pointing outside the ↵Patrick McHardy
packet commit 3a7b21eaf4fb3c971bdb47a98f570550ddfe4471 upstream. Some Cisco phones create huge messages that are spread over multiple packets. After calculating the offset of the SIP body, it is validated to be within the packet and the packet is dropped otherwise. This breaks operation of these phones. Since connection tracking is supposed to be passive, just let those packets pass unmodified and untracked. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> [bwh: Backported to 3.2: there is no log message to delete] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2013-11-28inet: fix possible memory corruption with UDP_CORK and UFOHannes Frederic Sowa
[ This is a simplified -stable version of a set of upstream commits. ] This is a replacement patch only for stable which does fix the problems handled by the following two commits in -net: "ip_output: do skb ufo init for peeked non ufo skb as well" (e93b7d748be887cd7639b113ba7d7ef792a7efb9) "ip6_output: do skb ufo init for peeked non ufo skb as well" (c547dbf55d5f8cf615ccc0e7265e98db27d3fb8b) Three frames are written on a corked udp socket for which the output netdevice has UFO enabled. If the first and third frame are smaller than the mtu and the second one is bigger, we enqueue the second frame with skb_append_datato_frags without initializing the gso fields. This leads to the third frame appended regulary and thus constructing an invalid skb. This fixes the problem by always using skb_append_datato_frags as soon as the first frag got enqueued to the skb without marking the packet as SKB_GSO_UDP. The problem with only two frames for ipv6 was fixed by "ipv6: udp packets following an UFO enqueued packet need also be handled by UFO" (2811ebac2521ceac84f2bdae402455baa6a7fb47). Cc: Jiri Pirko <jiri@resnulli.us> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: David Miller <davem@davemloft.net> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2013-11-28net: unix: inherit SOCK_PASS{CRED, SEC} flags from socket to fix raceDaniel Borkmann
[ Upstream commit 90c6bd34f884cd9cee21f1d152baf6c18bcac949 ] In the case of credentials passing in unix stream sockets (dgram sockets seem not affected), we get a rather sparse race after commit 16e5726 ("af_unix: dont send SCM_CREDENTIALS by default"). We have a stream server on receiver side that requests credential passing from senders (e.g. nc -U). Since we need to set SO_PASSCRED on each spawned/accepted socket on server side to 1 first (as it's not inherited), it can happen that in the time between accept() and setsockopt() we get interrupted, the sender is being scheduled and continues with passing data to our receiver. At that time SO_PASSCRED is neither set on sender nor receiver side, hence in cmsg's SCM_CREDENTIALS we get eventually pid:0, uid:65534, gid:65534 (== overflow{u,g}id) instead of what we actually would like to see. On the sender side, here nc -U, the tests in maybe_add_creds() invoked through unix_stream_sendmsg() would fail, as at that exact time, as mentioned, the sender has neither SO_PASSCRED on his side nor sees it on the server side, and we have a valid 'other' socket in place. Thus, sender believes it would just look like a normal connection, not needing/requesting SO_PASSCRED at that time. As reverting 16e5726 would not be an option due to the significant performance regression reported when having creds always passed, one way/trade-off to prevent that would be to set SO_PASSCRED on the listener socket and allow inheriting these flags to the spawned socket on server side in accept(). It seems also logical to do so if we'd tell the listener socket to pass those flags onwards, and would fix the race. Before, strace: recvmsg(4, {msg_name(0)=NULL, msg_iov(1)=[{"blub\n", 4096}], msg_controllen=32, {cmsg_len=28, cmsg_level=SOL_SOCKET, cmsg_type=SCM_CREDENTIALS{pid=0, uid=65534, gid=65534}}, msg_flags=0}, 0) = 5 After, strace: recvmsg(4, {msg_name(0)=NULL, msg_iov(1)=[{"blub\n", 4096}], msg_controllen=32, {cmsg_len=28, cmsg_level=SOL_SOCKET, cmsg_type=SCM_CREDENTIALS{pid=11580, uid=1000, gid=1000}}, msg_flags=0}, 0) = 5 Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2013-11-28sctp: Perform software checksum if packet has to be fragmented.Vlad Yasevich
[ Upstream commit d2dbbba77e95dff4b4f901fee236fef6d9552072 ] IP/IPv6 fragmentation knows how to compute only TCP/UDP checksum. This causes problems if SCTP packets has to be fragmented and ipsummed has been set to PARTIAL due to checksum offload support. This condition can happen when retransmitting after MTU discover, or when INIT or other control chunks are larger then MTU. Check for the rare fragmentation condition in SCTP and use software checksum calculation in this case. CC: Fan Du <fan.du@windriver.com> Signed-off-by: Vlad Yasevich <vyasevich@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2013-11-28sctp: Use software crc32 checksum when xfrm transform will happen.Fan Du
[ Upstream commit 27127a82561a2a3ed955ce207048e1b066a80a2a ] igb/ixgbe have hardware sctp checksum support, when this feature is enabled and also IPsec is armed to protect sctp traffic, ugly things happened as xfrm_output checks CHECKSUM_PARTIAL to do checksum operation(sum every thing up and pack the 16bits result in the checksum field). The result is fail establishment of sctp communication. Cc: Neil Horman <nhorman@tuxdriver.com> Cc: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Fan Du <fan.du@windriver.com> Signed-off-by: Vlad Yasevich <vyasevich@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2013-11-28l2tp: must disable bh before calling l2tp_xmit_skb()Eric Dumazet
[ Upstream commit 455cc32bf128e114455d11ad919321ab89a2c312 ] François Cachereul made a very nice bug report and suspected the bh_lock_sock() / bh_unlok_sock() pair used in l2tp_xmit_skb() from process context was not good. This problem was added by commit 6af88da14ee284aaad6e4326da09a89191ab6165 ("l2tp: Fix locking in l2tp_core.c"). l2tp_eth_dev_xmit() runs from BH context, so we must disable BH from other l2tp_xmit_skb() users. [ 452.060011] BUG: soft lockup - CPU#1 stuck for 23s! [accel-pppd:6662] [ 452.061757] Modules linked in: l2tp_ppp l2tp_netlink l2tp_core pppoe pppox ppp_generic slhc ipv6 ext3 mbcache jbd virtio_balloon xfs exportfs dm_mod virtio_blk ata_generic virtio_net floppy ata_piix libata virtio_pci virtio_ring virtio [last unloaded: scsi_wait_scan] [ 452.064012] CPU 1 [ 452.080015] BUG: soft lockup - CPU#2 stuck for 23s! [accel-pppd:6643] [ 452.080015] CPU 2 [ 452.080015] [ 452.080015] Pid: 6643, comm: accel-pppd Not tainted 3.2.46.mini #1 Bochs Bochs [ 452.080015] RIP: 0010:[<ffffffff81059f6c>] [<ffffffff81059f6c>] do_raw_spin_lock+0x17/0x1f [ 452.080015] RSP: 0018:ffff88007125fc18 EFLAGS: 00000293 [ 452.080015] RAX: 000000000000aba9 RBX: ffffffff811d0703 RCX: 0000000000000000 [ 452.080015] RDX: 00000000000000ab RSI: ffff8800711f6896 RDI: ffff8800745c8110 [ 452.080015] RBP: ffff88007125fc18 R08: 0000000000000020 R09: 0000000000000000 [ 452.080015] R10: 0000000000000000 R11: 0000000000000280 R12: 0000000000000286 [ 452.080015] R13: 0000000000000020 R14: 0000000000000240 R15: 0000000000000000 [ 452.080015] FS: 00007fdc0cc24700(0000) GS:ffff8800b6f00000(0000) knlGS:0000000000000000 [ 452.080015] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 452.080015] CR2: 00007fdb054899b8 CR3: 0000000074404000 CR4: 00000000000006a0 [ 452.080015] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 452.080015] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 [ 452.080015] Process accel-pppd (pid: 6643, threadinfo ffff88007125e000, task ffff8800b27e6dd0) [ 452.080015] Stack: [ 452.080015] ffff88007125fc28 ffffffff81256559 ffff88007125fc98 ffffffffa01b2bd1 [ 452.080015] ffff88007125fc58 000000000000000c 00000000029490d0 0000009c71dbe25e [ 452.080015] 000000000000005c 000000080000000e 0000000000000000 ffff880071170600 [ 452.080015] Call Trace: [ 452.080015] [<ffffffff81256559>] _raw_spin_lock+0xe/0x10 [ 452.080015] [<ffffffffa01b2bd1>] l2tp_xmit_skb+0x189/0x4ac [l2tp_core] [ 452.080015] [<ffffffffa01c2d36>] pppol2tp_sendmsg+0x15e/0x19c [l2tp_ppp] [ 452.080015] [<ffffffff811c7872>] __sock_sendmsg_nosec+0x22/0x24 [ 452.080015] [<ffffffff811c83bd>] sock_sendmsg+0xa1/0xb6 [ 452.080015] [<ffffffff81254e88>] ? __schedule+0x5c1/0x616 [ 452.080015] [<ffffffff8103c7c6>] ? __dequeue_signal+0xb7/0x10c [ 452.080015] [<ffffffff810bbd21>] ? fget_light+0x75/0x89 [ 452.080015] [<ffffffff811c8444>] ? sockfd_lookup_light+0x20/0x56 [ 452.080015] [<ffffffff811c9b34>] sys_sendto+0x10c/0x13b [ 452.080015] [<ffffffff8125cac2>] system_call_fastpath+0x16/0x1b [ 452.080015] Code: 81 48 89 e5 72 0c 31 c0 48 81 ff 45 66 25 81 0f 92 c0 5d c3 55 b8 00 01 00 00 48 89 e5 f0 66 0f c1 07 0f b6 d4 38 d0 74 06 f3 90 <8a> 07 eb f6 5d c3 90 90 55 48 89 e5 9c 58 0f 1f 44 00 00 5d c3 [ 452.080015] Call Trace: [ 452.080015] [<ffffffff81256559>] _raw_spin_lock+0xe/0x10 [ 452.080015] [<ffffffffa01b2bd1>] l2tp_xmit_skb+0x189/0x4ac [l2tp_core] [ 452.080015] [<ffffffffa01c2d36>] pppol2tp_sendmsg+0x15e/0x19c [l2tp_ppp] [ 452.080015] [<ffffffff811c7872>] __sock_sendmsg_nosec+0x22/0x24 [ 452.080015] [<ffffffff811c83bd>] sock_sendmsg+0xa1/0xb6 [ 452.080015] [<ffffffff81254e88>] ? __schedule+0x5c1/0x616 [ 452.080015] [<ffffffff8103c7c6>] ? __dequeue_signal+0xb7/0x10c [ 452.080015] [<ffffffff810bbd21>] ? fget_light+0x75/0x89 [ 452.080015] [<ffffffff811c8444>] ? sockfd_lookup_light+0x20/0x56 [ 452.080015] [<ffffffff811c9b34>] sys_sendto+0x10c/0x13b [ 452.080015] [<ffffffff8125cac2>] system_call_fastpath+0x16/0x1b [ 452.064012] [ 452.064012] Pid: 6662, comm: accel-pppd Not tainted 3.2.46.mini #1 Bochs Bochs [ 452.064012] RIP: 0010:[<ffffffff81059f6e>] [<ffffffff81059f6e>] do_raw_spin_lock+0x19/0x1f [ 452.064012] RSP: 0018:ffff8800b6e83ba0 EFLAGS: 00000297 [ 452.064012] RAX: 000000000000aaa9 RBX: ffff8800b6e83b40 RCX: 0000000000000002 [ 452.064012] RDX: 00000000000000aa RSI: 000000000000000a RDI: ffff8800745c8110 [ 452.064012] RBP: ffff8800b6e83ba0 R08: 000000000000c802 R09: 000000000000001c [ 452.064012] R10: ffff880071096c4e R11: 0000000000000006 R12: ffff8800b6e83b18 [ 452.064012] R13: ffffffff8125d51e R14: ffff8800b6e83ba0 R15: ffff880072a589c0 [ 452.064012] FS: 00007fdc0b81e700(0000) GS:ffff8800b6e80000(0000) knlGS:0000000000000000 [ 452.064012] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 452.064012] CR2: 0000000000625208 CR3: 0000000074404000 CR4: 00000000000006a0 [ 452.064012] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 452.064012] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 [ 452.064012] Process accel-pppd (pid: 6662, threadinfo ffff88007129a000, task ffff8800744f7410) [ 452.064012] Stack: [ 452.064012] ffff8800b6e83bb0 ffffffff81256559 ffff8800b6e83bc0 ffffffff8121c64a [ 452.064012] ffff8800b6e83bf0 ffffffff8121ec7a ffff880072a589c0 ffff880071096c62 [ 452.064012] 0000000000000011 ffffffff81430024 ffff8800b6e83c80 ffffffff8121f276 [ 452.064012] Call Trace: [ 452.064012] <IRQ> [ 452.064012] [<ffffffff81256559>] _raw_spin_lock+0xe/0x10 [ 452.064012] [<ffffffff8121c64a>] spin_lock+0x9/0xb [ 452.064012] [<ffffffff8121ec7a>] udp_queue_rcv_skb+0x186/0x269 [ 452.064012] [<ffffffff8121f276>] __udp4_lib_rcv+0x297/0x4ae [ 452.064012] [<ffffffff8121c178>] ? raw_rcv+0xe9/0xf0 [ 452.064012] [<ffffffff8121f4a7>] udp_rcv+0x1a/0x1c [ 452.064012] [<ffffffff811fe385>] ip_local_deliver_finish+0x12b/0x1a5 [ 452.064012] [<ffffffff811fe54e>] ip_local_deliver+0x53/0x84 [ 452.064012] [<ffffffff811fe1d0>] ip_rcv_finish+0x2bc/0x2f3 [ 452.064012] [<ffffffff811fe78f>] ip_rcv+0x210/0x269 [ 452.064012] [<ffffffff8101911e>] ? kvm_clock_get_cycles+0x9/0xb [ 452.064012] [<ffffffff811d88cd>] __netif_receive_skb+0x3a5/0x3f7 [ 452.064012] [<ffffffff811d8eba>] netif_receive_skb+0x57/0x5e [ 452.064012] [<ffffffff811cf30f>] ? __netdev_alloc_skb+0x1f/0x3b [ 452.064012] [<ffffffffa0049126>] virtnet_poll+0x4ba/0x5a4 [virtio_net] [ 452.064012] [<ffffffff811d9417>] net_rx_action+0x73/0x184 [ 452.064012] [<ffffffffa01b2cc2>] ? l2tp_xmit_skb+0x27a/0x4ac [l2tp_core] [ 452.064012] [<ffffffff810343b9>] __do_softirq+0xc3/0x1a8 [ 452.064012] [<ffffffff81013b56>] ? ack_APIC_irq+0x10/0x12 [ 452.064012] [<ffffffff81256559>] ? _raw_spin_lock+0xe/0x10 [ 452.064012] [<ffffffff8125e0ac>] call_softirq+0x1c/0x26 [ 452.064012] [<ffffffff81003587>] do_softirq+0x45/0x82 [ 452.064012] [<ffffffff81034667>] irq_exit+0x42/0x9c [ 452.064012] [<ffffffff8125e146>] do_IRQ+0x8e/0xa5 [ 452.064012] [<ffffffff8125676e>] common_interrupt+0x6e/0x6e [ 452.064012] <EOI> [ 452.064012] [<ffffffff810b82a1>] ? kfree+0x8a/0xa3 [ 452.064012] [<ffffffffa01b2cc2>] ? l2tp_xmit_skb+0x27a/0x4ac [l2tp_core] [ 452.064012] [<ffffffffa01b2c25>] ? l2tp_xmit_skb+0x1dd/0x4ac [l2tp_core] [ 452.064012] [<ffffffffa01c2d36>] pppol2tp_sendmsg+0x15e/0x19c [l2tp_ppp] [ 452.064012] [<ffffffff811c7872>] __sock_sendmsg_nosec+0x22/0x24 [ 452.064012] [<ffffffff811c83bd>] sock_sendmsg+0xa1/0xb6 [ 452.064012] [<ffffffff81254e88>] ? __schedule+0x5c1/0x616 [ 452.064012] [<ffffffff8103c7c6>] ? __dequeue_signal+0xb7/0x10c [ 452.064012] [<ffffffff810bbd21>] ? fget_light+0x75/0x89 [ 452.064012] [<ffffffff811c8444>] ? sockfd_lookup_light+0x20/0x56 [ 452.064012] [<ffffffff811c9b34>] sys_sendto+0x10c/0x13b [ 452.064012] [<ffffffff8125cac2>] system_call_fastpath+0x16/0x1b [ 452.064012] Code: 89 e5 72 0c 31 c0 48 81 ff 45 66 25 81 0f 92 c0 5d c3 55 b8 00 01 00 00 48 89 e5 f0 66 0f c1 07 0f b6 d4 38 d0 74 06 f3 90 8a 07 <eb> f6 5d c3 90 90 55 48 89 e5 9c 58 0f 1f 44 00 00 5d c3 55 48 [ 452.064012] Call Trace: [ 452.064012] <IRQ> [<ffffffff81256559>] _raw_spin_lock+0xe/0x10 [ 452.064012] [<ffffffff8121c64a>] spin_lock+0x9/0xb [ 452.064012] [<ffffffff8121ec7a>] udp_queue_rcv_skb+0x186/0x269 [ 452.064012] [<ffffffff8121f276>] __udp4_lib_rcv+0x297/0x4ae [ 452.064012] [<ffffffff8121c178>] ? raw_rcv+0xe9/0xf0 [ 452.064012] [<ffffffff8121f4a7>] udp_rcv+0x1a/0x1c [ 452.064012] [<ffffffff811fe385>] ip_local_deliver_finish+0x12b/0x1a5 [ 452.064012] [<ffffffff811fe54e>] ip_local_deliver+0x53/0x84 [ 452.064012] [<ffffffff811fe1d0>] ip_rcv_finish+0x2bc/0x2f3 [ 452.064012] [<ffffffff811fe78f>] ip_rcv+0x210/0x269 [ 452.064012] [<ffffffff8101911e>] ? kvm_clock_get_cycles+0x9/0xb [ 452.064012] [<ffffffff811d88cd>] __netif_receive_skb+0x3a5/0x3f7 [ 452.064012] [<ffffffff811d8eba>] netif_receive_skb+0x57/0x5e [ 452.064012] [<ffffffff811cf30f>] ? __netdev_alloc_skb+0x1f/0x3b [ 452.064012] [<ffffffffa0049126>] virtnet_poll+0x4ba/0x5a4 [virtio_net] [ 452.064012] [<ffffffff811d9417>] net_rx_action+0x73/0x184 [ 452.064012] [<ffffffffa01b2cc2>] ? l2tp_xmit_skb+0x27a/0x4ac [l2tp_core] [ 452.064012] [<ffffffff810343b9>] __do_softirq+0xc3/0x1a8 [ 452.064012] [<ffffffff81013b56>] ? ack_APIC_irq+0x10/0x12 [ 452.064012] [<ffffffff81256559>] ? _raw_spin_lock+0xe/0x10 [ 452.064012] [<ffffffff8125e0ac>] call_softirq+0x1c/0x26 [ 452.064012] [<ffffffff81003587>] do_softirq+0x45/0x82 [ 452.064012] [<ffffffff81034667>] irq_exit+0x42/0x9c [ 452.064012] [<ffffffff8125e146>] do_IRQ+0x8e/0xa5 [ 452.064012] [<ffffffff8125676e>] common_interrupt+0x6e/0x6e [ 452.064012] <EOI> [<ffffffff810b82a1>] ? kfree+0x8a/0xa3 [ 452.064012] [<ffffffffa01b2cc2>] ? l2tp_xmit_skb+0x27a/0x4ac [l2tp_core] [ 452.064012] [<ffffffffa01b2c25>] ? l2tp_xmit_skb+0x1dd/0x4ac [l2tp_core] [ 452.064012] [<ffffffffa01c2d36>] pppol2tp_sendmsg+0x15e/0x19c [l2tp_ppp] [ 452.064012] [<ffffffff811c7872>] __sock_sendmsg_nosec+0x22/0x24 [ 452.064012] [<ffffffff811c83bd>] sock_sendmsg+0xa1/0xb6 [ 452.064012] [<ffffffff81254e88>] ? __schedule+0x5c1/0x616 [ 452.064012] [<ffffffff8103c7c6>] ? __dequeue_signal+0xb7/0x10c [ 452.064012] [<ffffffff810bbd21>] ? fget_light+0x75/0x89 [ 452.064012] [<ffffffff811c8444>] ? sockfd_lookup_light+0x20/0x56 [ 452.064012] [<ffffffff811c9b34>] sys_sendto+0x10c/0x13b [ 452.064012] [<ffffffff8125cac2>] system_call_fastpath+0x16/0x1b Reported-by: François Cachereul <f.cachereul@alphalink.fr> Tested-by: François Cachereul <f.cachereul@alphalink.fr> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: James Chapman <jchapman@katalix.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2013-11-28net: vlan: fix nlmsg size calculation in vlan_get_size()Marc Kleine-Budde
[ Upstream commit c33a39c575068c2ea9bffb22fd6de2df19c74b89 ] This patch fixes the calculation of the nlmsg size, by adding the missing nla_total_size(). Cc: Patrick McHardy <kaber@trash.net> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2013-11-28ipv6: restrict neighbor entry creation to output flowMarcelo Ricardo Leitner
This patch is based on 3.2.y branch, the one used by reporter. Please let me know if it should be different. Thanks. The patch which introduced the regression was applied on stables: 3.0.64 3.4.31 3.7.8 3.2.39 The patch which introduced the regression was for stable trees only. ---8<--- Commit 0d6a77079c475033cb622c07c5a880b392ef664e "ipv6: do not create neighbor entries for local delivery" introduced a regression on which routes to local delivery would not work anymore. Like this: $ ip -6 route add local 2001::/64 dev lo $ ping6 -c1 2001::9 PING 2001::9(2001::9) 56 data bytes ping: sendmsg: Invalid argument As this is a local delivery, that commit would not allow the creation of a neighbor entry and thus the packet cannot be sent. But as TPROXY scenario actually needs to avoid the neighbor entry creation only for input flow, this patch now limits previous patch to input flow, keeping output as before that patch. Reported-by: Debabrata Banerjee <dbavatar@gmail.com> Signed-off-by: Marcelo Ricardo Leitner <mleitner@redhat.com> Signed-off-by: Jiri Pirko <jiri@resnulli.us> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> CC: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2013-11-28ipv4: fix ineffective source address selectionJiri Benc
[ Upstream commit 0a7e22609067ff524fc7bbd45c6951dd08561667 ] When sending out multicast messages, the source address in inet->mc_addr is ignored and rewritten by an autoselected one. This is caused by a typo in commit 813b3b5db831 ("ipv4: Use caller's on-stack flowi as-is in output route lookups"). Signed-off-by: Jiri Benc <jbenc@redhat.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2013-11-28net: heap overflow in __audit_sockaddr()Dan Carpenter
[ Upstream commit 1661bf364ae9c506bc8795fef70d1532931be1e8 ] We need to cap ->msg_namelen or it leads to a buffer overflow when we to the memcpy() in __audit_sockaddr(). It requires CAP_AUDIT_CONTROL to exploit this bug. The call tree is: ___sys_recvmsg() move_addr_to_user() audit_sockaddr() __audit_sockaddr() Reported-by: Jüri Aedla <juri.aedla@gmail.com> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2013-11-28net: do not call sock_put() on TIMEWAIT socketsEric Dumazet
[ Upstream commit 80ad1d61e72d626e30ebe8529a0455e660ca4693 ] commit 3ab5aee7fe84 ("net: Convert TCP & DCCP hash tables to use RCU / hlist_nulls") incorrectly used sock_put() on TIMEWAIT sockets. We should instead use inet_twsk_put() Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2013-11-28tcp: do not forget FIN in tcp_shifted_skb()Eric Dumazet
[ Upstream commit 5e8a402f831dbe7ee831340a91439e46f0d38acd ] Yuchung found following problem : There are bugs in the SACK processing code, merging part in tcp_shift_skb_data(), that incorrectly resets or ignores the sacked skbs FIN flag. When a receiver first SACK the FIN sequence, and later throw away ofo queue (e.g., sack-reneging), the sender will stop retransmitting the FIN flag, and hangs forever. Following packetdrill test can be used to reproduce the bug. $ cat sack-merge-bug.pkt `sysctl -q net.ipv4.tcp_fack=0` // Establish a connection and send 10 MSS. 0.000 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3 +.000 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0 +.000 bind(3, ..., ...) = 0 +.000 listen(3, 1) = 0 +.050 < S 0:0(0) win 32792 <mss 1000,sackOK,nop,nop,nop,wscale 7> +.000 > S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK,nop,wscale 6> +.001 < . 1:1(0) ack 1 win 1024 +.000 accept(3, ..., ...) = 4 +.100 write(4, ..., 12000) = 12000 +.000 shutdown(4, SHUT_WR) = 0 +.000 > . 1:10001(10000) ack 1 +.050 < . 1:1(0) ack 2001 win 257 +.000 > FP. 10001:12001(2000) ack 1 +.050 < . 1:1(0) ack 2001 win 257 <sack 10001:11001,nop,nop> +.050 < . 1:1(0) ack 2001 win 257 <sack 10001:12002,nop,nop> // SACK reneg +.050 < . 1:1(0) ack 12001 win 257 +0 %{ print "unacked: ",tcpi_unacked }% +5 %{ print "" }% First, a typo inverted left/right of one OR operation, then code forgot to advance end_seq if the merged skb carried FIN. Bug was added in 2.6.29 by commit 832d11c5cd076ab ("tcp: Try to restore large SKBs while SACK processing") Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Cc: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Acked-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>