linux/net/ipv4, branch v3.4.19

net: inet_diag -- Return error code if protocol handler is missed

2012-11-17T21:16:19Z

[ Upstream commit cacb6ba0f36ab14a507f4ee7697e8332899015d2 ] We've observed that in case if UDP diag module is not supported in kernel the netlink returns NLMSG_DONE without notifying a caller that handler is missed. This patch makes __inet_diag_dump to return error code instead. So as example it become possible to detect such situation and handle it gracefully on userspace level. Signed-off-by: Cyrill Gorcunov CC: David Miller CC: Eric Dumazet CC: Pavel Emelyanov Acked-by: Pavel Emelyanov Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: fix divide by zero in tcp algorithm illinois

2012-11-17T21:16:17Z

[ Upstream commit 8f363b77ee4fbf7c3bbcf5ec2c5ca482d396d664 ] Reading TCP stats when using TCP Illinois congestion control algorithm can cause a divide by zero kernel oops. The division by zero occur in tcp_illinois_info() at: do_div(t, ca->cnt_rtt); where ca->cnt_rtt can become zero (when rtt_reset is called) Steps to Reproduce: 1. Register tcp_illinois: # sysctl -w net.ipv4.tcp_congestion_control=illinois 2. Monitor internal TCP information via command "ss -i" # watch -d ss -i 3. Establish new TCP conn to machine Either it fails at the initial conn, or else it needs to wait for a loss or a reset. This is only related to reading stats. The function avg_delay() also performs the same divide, but is guarded with a (ca->cnt_rtt > 0) at its calling point in update_params(). Thus, simply fix tcp_illinois_info(). Function tcp_illinois_info() / get_info() is called without socket lock. Thus, eliminate any race condition on ca->cnt_rtt by using a local stack variable. Simply reuse info.tcpv_rttcnt, as its already set to ca->cnt_rtt. Function avg_delay() is not affected by this race condition, as its called with the socket lock. Cc: Petr Matousek Signed-off-by: Jesper Dangaard Brouer Acked-by: Eric Dumazet Acked-by: Stephen Hemminger Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

tcp: fix FIONREAD/SIOCINQ

2012-11-17T21:16:15Z

[ Upstream commit a3374c42aa5f7237e87ff3b0622018636b0c847e ] tcp_ioctl() tries to take into account if tcp socket received a FIN to report correct number bytes in receive queue. But its flaky because if the application ate the last skb, we return 1 instead of 0. Correct way to detect that FIN was received is to test SOCK_DONE. Reported-by: Elliot Hughes Signed-off-by: Eric Dumazet Cc: Neal Cardwell Cc: Tom Herbert Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

tcp: resets are misrouted

2012-10-28T17:14:16Z

[ Upstream commit 4c67525849e0b7f4bd4fab2487ec9e43ea52ef29 ] After commit e2446eaa ("tcp_v4_send_reset: binding oif to iif in no sock case").. tcp resets are always lost, when routing is asymmetric. Yes, backing out that patch will result in misrouting of resets for dead connections which used interface binding when were alive, but we actually cannot do anything here. What's died that's died and correct handling normal unbound connections is obviously a priority. Comment to comment: > This has few benefits: > 1. tcp_v6_send_reset already did that. It was done to route resets for IPv6 link local addresses. It was a mistake to do so for global addresses. The patch fixes this as well. Actually, the problem appears to be even more serious than guaranteed loss of resets. As reported by Sergey Soloviev , those misrouted resets create a lot of arp traffic and huge amount of unresolved arp entires putting down to knees NAT firewalls which use asymmetric routing. Signed-off-by: Alexey Kuznetsov Signed-off-by: Greg Kroah-Hartman

netfilter: nf_nat_sip: fix via header translation with multiple parameters

2012-10-21T16:28:00Z

commit f22eb25cf5b1157b29ef88c793b71972efc47143 upstream. Via-headers are parsed beginning at the first character after the Via-address. When the address is translated first and its length decreases, the offset to start parsing at is incorrect and header parameters might be missed. Update the offset after translating the Via-address to fix this. Signed-off-by: Patrick McHardy Signed-off-by: Pablo Neira Ayuso Acked-by: David Miller Signed-off-by: Greg Kroah-Hartman

netfilter: nf_nat_sip: fix incorrect handling of EBUSY for RTCP expectation

2012-10-21T16:28:00Z

commit 3f509c689a07a4aa989b426893d8491a7ffcc410 upstream. We're hitting bug while trying to reinsert an already existing expectation: kernel BUG at kernel/timer.c:895! invalid opcode: 0000 [#1] SMP [...] Call Trace: [] nf_ct_expect_related_report+0x4a0/0x57a [nf_conntrack] [] ? in4_pton+0x72/0x131 [] ip_nat_sdp_media+0xeb/0x185 [nf_nat_sip] [] set_expected_rtp_rtcp+0x32d/0x39b [nf_conntrack_sip] [] process_sdp+0x30c/0x3ec [nf_conntrack_sip] [] ? irq_exit+0x9a/0x9c [] ? ip_nat_sdp_media+0x185/0x185 [nf_nat_sip] We have to remove the RTP expectation if the RTCP expectation hits EBUSY since we keep trying with other ports until we succeed. Reported-by: Rafal Fitt Acked-by: David Miller Signed-off-by: Pablo Neira Ayuso Signed-off-by: Greg Kroah-Hartman

ipv4: raw: fix icmp_filter()

2012-10-12T20:38:44Z

[ Upstream commit ab43ed8b7490cb387782423ecf74aeee7237e591 ] icmp_filter() should not modify its input, or else its caller would need to recompute ip_hdr() if skb->head is reallocated. Use skb_header_pointer() instead of pskb_may_pull() and change the prototype to make clear both sk and skb are const. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

tcp: flush DMA queue before sk_wait_data if rcv_wnd is zero

2012-10-12T20:38:43Z

[ Upstream commit 15c041759bfcd9ab0a4e43f1c16e2644977d0467 ] If recv() syscall is called for a TCP socket so that - IOAT DMA is used - MSG_WAITALL flag is used - requested length is bigger than sk_rcvbuf - enough data has already arrived to bring rcv_wnd to zero then when tcp_recvmsg() gets to calling sk_wait_data(), receive window can be still zero while sk_async_wait_queue exhausts enough space to keep it zero. As this queue isn't cleaned until the tcp_service_net_dma() call, sk_wait_data() cannot receive any data and blocks forever. If zero receive window and non-empty sk_async_wait_queue is detected before calling sk_wait_data(), process the queue first. Signed-off-by: Michal Kubecek Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: ipv4: ipmr_expire_timer causes crash when removing net namespace

2012-10-02T17:29:50Z

[ Upstream commit acbb219d5f53821b2d0080d047800410c0420ea1 ] When tearing down a net namespace, ipv4 mr_table structures are freed without first deactivating their timers. This can result in a crash in run_timer_softirq. This patch mimics the corresponding behaviour in ipv6. Locking and synchronization seem to be adequate. We are about to kfree mrt, so existing code should already make sure that no other references to mrt are pending or can be created by incoming traffic. The functions invoked here do not cause new references to mrt or other race conditions to be created. Invoking del_timer_sync guarantees that ipmr_expire_timer is inactive. Both ipmr_expire_process (whose completion we may have to wait in del_timer_sync) and mroute_clean_tables internally use mfc_unres_lock or other synchronizations when needed, and they both only modify mrt. Tested in Linux 3.4.8. Signed-off-by: Francesco Ruggeri Signed-off-by: David S. Miller

tcp: fix cwnd reduction for non-sack recovery

2012-10-02T17:29:38Z

[ Upstream commit 7c4a56fec379ac0d7754e0d4da6a7361f1a4fe64 ] The cwnd reduction in fast recovery is based on the number of packets newly delivered per ACK. For non-sack connections every DUPACK signifies a packet has been delivered, but the sender mistakenly skips counting them for cwnd reduction. The fix is to compute newly_acked_sacked after DUPACKs are accounted in sacked_out for non-sack connections. Signed-off-by: Yuchung Cheng Acked-by: Nandita Dukkipati Acked-by: Neal Cardwell Signed-off-by: David S. Miller