linux/net, branch v3.8.11

net: drop dst before queueing fragments

2013-05-01T16:46:20Z

[ Upstream commit 97599dc792b45b1669c3cdb9a4b365aad0232f65 ] Commit 4a94445c9a5c (net: Use ip_route_input_noref() in input path) added a bug in IP defragmentation handling, as non refcounted dst could escape an RCU protected section. Commit 64f3b9e203bd068 (net: ip_expire() must revalidate route) fixed the case of timeouts, but not the general problem. Tom Parkin noticed crashes in UDP stack and provided a patch, but further analysis permitted us to pinpoint the root cause. Before queueing a packet into a frag list, we must drop its dst, as this dst has limited lifetime (RCU protected) When/if a packet is finally reassembled, we use the dst of the very last skb, still protected by RCU and valid, as the dst of the reassembled packet. Use same logic in IPv6, as there is no need to hold dst references. Reported-by: Tom Parkin Tested-by: Tom Parkin Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: rate-limit warn-bad-offload splats.

2013-05-01T16:46:20Z

[ Upstream commit c846ad9b880ece01bb4d8d07ba917734edf0324f ] If one does do something unfortunate and allow a bad offload bug into the kernel, this the skb_warn_bad_offload can effectively live-lock the system, filling the logs with the same error over and over. Add rate limitation to this so that box remains otherwise functional in this case. Signed-off-by: Ben Greear Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

tcp: call tcp_replace_ts_recent() from tcp_ack()

2013-05-01T16:46:19Z

[ Upstream commit 12fb3dd9dc3c64ba7d64cec977cca9b5fb7b1d4e ] commit bd090dfc634d (tcp: tcp_replace_ts_recent() should not be called from tcp_validate_incoming()) introduced a TS ecr bug in slow path processing. 1 A > B P. 1:10001(10000) ack 1 2 B < A . 1:1(0) ack 1 win 257 3 A > B . 1:1001(1000) ack 1 win 227 4 A > B . 1001:2001(1000) ack 1 win 227 (ecr 200 should be ecr 300 in packets 3 & 4) Problem is tcp_ack() can trigger send of new packets (retransmits), reflecting the prior TSval, instead of the TSval contained in the currently processed incoming packet. Fix this by calling tcp_replace_ts_recent() from tcp_ack() after the checks, but before the actions. Reported-by: Yuchung Cheng Signed-off-by: Eric Dumazet Cc: Neal Cardwell Acked-by: Neal Cardwell Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

esp4: fix error return code in esp_output()

2013-05-01T16:46:19Z

[ Upstream commit 06848c10f720cbc20e3b784c0df24930b7304b93 ] Fix to return a negative error code from the error handling case instead of 0, as returned elsewhere in this function. Signed-off-by: Wei Yongjun Acked-by: Steffen Klassert Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

tcp: Reallocate headroom if it would overflow csum_start

2013-05-01T16:46:18Z

[ Upstream commit 50bceae9bd3569d56744882f3012734d48a1d413 ] If a TCP retransmission gets partially ACKed and collapsed multiple times it is possible for the headroom to grow beyond 64K which will overflow the 16bit skb->csum_start which is based on the start of the headroom. It has been observed rarely in the wild with IPoIB due to the 64K MTU. Verify if the acking and collapsing resulted in a headroom exceeding what csum_start can cover and reallocate the headroom if so. A big thank you to Jim Foraker and the team at LLNL for helping out with the investigation and testing. Reported-by: Jim Foraker Signed-off-by: Thomas Graf Acked-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

tcp: incoming connections might use wrong route under synflood

2013-05-01T16:46:18Z

[ Upstream commit d66954a066158781ccf9c13c91d0316970fe57b6 ] There is a bug in cookie_v4_check (net/ipv4/syncookies.c): flowi4_init_output(&fl4, 0, sk->sk_mark, RT_CONN_FLAGS(sk), RT_SCOPE_UNIVERSE, IPPROTO_TCP, inet_sk_flowi_flags(sk), (opt && opt->srr) ? opt->faddr : ireq->rmt_addr, ireq->loc_addr, th->source, th->dest); Here we do not respect sk->sk_bound_dev_if, therefore wrong dst_entry may be taken. This dst_entry is used by new socket (get_cookie_sock -> tcp_v4_syn_recv_sock), so its packets may take the wrong path. Signed-off-by: Dmitry Popov Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

rtnetlink: Call nlmsg_parse() with correct header length

2013-05-01T16:46:18Z

[ Upstream commit 88c5b5ce5cb57af6ca2a7cf4d5715fa320448ff9 ] Signed-off-by: Michael Riesch Cc: Jiri Benc Cc: "Theodore Ts'o" Acked-by: Mark Rustad Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

ipv6/tcp: Stop processing ICMPv6 redirect messages

2013-05-01T16:46:18Z

[ Upstream commit 50a75a8914539c5dcd441c5f54d237a666a426fd ] Tetja Rediske found that if the host receives an ICMPv6 redirect message after sending a SYN+ACK, the connection will be reset. He bisected it down to 093d04d (ipv6: Change skb->data before using icmpv6_notify() to propagate redirect), but the origin of the bug comes from ec18d9a26 (ipv6: Add redirect support to all protocol icmp error handlers.). The bug simply did not trigger prior to 093d04d, because skb->data did not point to the inner IP header and thus icmpv6_notify did not call the correct err_handler. This patch adds the missing "goto out;" in tcp_v6_err. After receiving an ICMPv6 Redirect, we should not continue processing the ICMP in tcp_v6_err, as this may trigger the removal of request-socks or setting sk_err(_soft). Reported-by: Tetja Rediske Signed-off-by: Christoph Paasch Acked-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

netfilter: don't reset nf_trace in nf_reset()

2013-05-01T16:46:17Z

[ Upstream commit 124dff01afbdbff251f0385beca84ba1b9adda68 ] Commit 130549fe ("netfilter: reset nf_trace in nf_reset") added code to reset nf_trace in nf_reset(). This is wrong and unnecessary. nf_reset() is used in the following cases: - when passing packets up the the socket layer, at which point we want to release all netfilter references that might keep modules pinned while the packet is queued. nf_trace doesn't matter anymore at this point. - when encapsulating or decapsulating IPsec packets. We want to continue tracing these packets after IPsec processing. - when passing packets through virtual network devices. Only devices on that encapsulate in IPv4/v6 matter since otherwise nf_trace is not used anymore. Its not entirely clear whether those packets should be traced after that, however we've always done that. - when passing packets through virtual network devices that make the packet cross network namespace boundaries. This is the only cases where we clearly want to reset nf_trace and is also what the original patch intended to fix. Add a new function nf_reset_trace() and use it in dev_forward_skb() to fix this properly. Signed-off-by: Patrick McHardy Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

af_unix: If we don't care about credentials coallesce all messages

2013-05-01T16:46:17Z

[ Upstream commit 0e82e7f6dfeec1013339612f74abc2cdd29d43d2 ] It was reported that the following LSB test case failed https://lsbbugs.linuxfoundation.org/attachment.cgi?id=2144 because we were not coallescing unix stream messages when the application was expecting us to. The problem was that the first send was before the socket was accepted and thus sock->sk_socket was NULL in maybe_add_creds, and the second send after the socket was accepted had a non-NULL value for sk->socket and thus we could tell the credentials were not needed so we did not bother. The unnecessary credentials on the first message cause unix_stream_recvmsg to start verifying that all messages had the same credentials before coallescing and then the coallescing failed because the second message had no credentials. Ignoring credentials when we don't care in unix_stream_recvmsg fixes a long standing pessimization which would fail to coallesce messages when reading from a unix stream socket if the senders were different even if we did not care about their credentials. I have tested this and verified that the in the LSB test case mentioned above that the messages do coallesce now, while the were failing to coallesce without this change. Reported-by: Karel Srot Reported-by: Ding Tianhong Signed-off-by: "Eric W. Biederman" Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman