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2008-06-16tcp: Fix inconsistency source (CA_Open only when !tcp_left_out(tp))Ilpo Järvinen
[ upstream commit: 8aca6cb1179ed9bef9351028c8d8af852903eae2 ] It is possible that this skip path causes TCP to end up into an invalid state where ca_state was left to CA_Open while some segments already came into sacked_out. If next valid ACK doesn't contain new SACK information TCP fails to enter into tcp_fastretrans_alert(). Thus at least high_seq is set incorrectly to a too high seqno because some new data segments could be sent in between (and also, limited transmit is not being correctly invoked there). Reordering in both directions can easily cause this situation to occur. I guess we would want to use tcp_moderate_cwnd(tp) there as well as it may be possible to use this to trigger oversized burst to network by sending an old ACK with huge amount of SACK info, but I'm a bit unsure about its effects (mainly to FlightSize), so to be on the safe side I just currently fixed it minimally to keep TCP's state consistent (obviously, such nasty ACKs have been possible this far). Though it seems that FlightSize is already underestimated by some amount, so probably on the long term we might want to trigger recovery there too, if appropriate, to make FlightSize calculation to resemble reality at the time when the losses where discovered (but such change scares me too much now and requires some more thinking anyway how to do that as it likely involves some code shuffling). This bug was found by Brian Vowell while running my TCP debug patch to find cause of another TCP issue (fackets_out miscount). Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-06-16tcp FRTO: work-around inorder receiversIlpo Järvinen
[ upstream commit: 79d44516b4b178ffb6e2159c75584cfcfc097914 ] If receiver consumes segments successfully only in-order, FRTO fallback to conventional recovery produces RTO loop because FRTO's forward transmissions will always get dropped and need to be resent, yet by default they're not marked as lost (which are the only segments we will retransmit in CA_Loss). Price to pay about this is occassionally unnecessarily retransmitting the forward transmission(s). SACK blocks help a bit to avoid this, so it's mainly a concern for NewReno case though SACK is not fully immune either. This change has a side-effect of fixing SACKFRTO problem where it didn't have snd_nxt of the RTO time available anymore when fallback become necessary (this problem would have only occured when RTO would occur for two or more segments and ECE arrives in step 3; no need to figure out how to fix that unless the TODO item of selective behavior is considered in future). Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Reported-by: Damon L. Chesser <damon@damtek.com> Tested-by: Damon L. Chesser <damon@damtek.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Chris Wright <chrisw@sous-sol.org>
2008-06-16tcp FRTO: SACK variant is errorneously used with NewRenoIlpo Järvinen
[ upstream commit: 62ab22278308a40bcb7f4079e9719ab8b7fe11b5 ] Note: there's actually another bug in FRTO's SACK variant, which is the causing failure in NewReno case because of the error that's fixed here. I'll fix the SACK case separately (it's a separate bug really, though related, but in order to fix that I need to audit tp->snd_nxt usage a bit). There were two places where SACK variant of FRTO is getting incorrectly used even if SACK wasn't negotiated by the TCP flow. This leads to incorrect setting of frto_highmark with NewReno if a previous recovery was interrupted by another RTO. An eventual fallback to conventional recovery then incorrectly considers one or couple of segments as forward transmissions though they weren't, which then are not LOST marked during fallback making them "non-retransmittable" until the next RTO. In a bad case, those segments are really lost and are the only one left in the window. Thus TCP needs another RTO to continue. The next FRTO, however, could again repeat the same events making the progress of the TCP flow extremely slow. In order for these events to occur at all, FRTO must occur again in FRTOs step 3 while the key segments must be lost as well, which is not too likely in practice. It seems to most frequently with some small devices such as network printers that *seem* to accept TCP segments only in-order. In cases were key segments weren't lost, things get automatically resolved because those wrongly marked segments don't need to be retransmitted in order to continue. I found a reproducer after digging up relevant reports (few reports in total, none at netdev or lkml I know of), some cases seemed to indicate middlebox issues which seems now to be a false assumption some people had made. Bugzilla #10063 _might_ be related. Damon L. Chesser <damon@damtek.com> had a reproducable case and was kind enough to tcpdump it for me. With the tcpdump log it was quite trivial to figure out. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Chris Wright <chrisw@sous-sol.org>
2008-06-16tcp FRTO: Fix fallback to conventional recoveryIlpo Järvinen
[ upstream commit: a1c1f281b84a751fdb5ff919da3b09df7297619f ] It seems that commit 009a2e3e4ec ("[TCP] FRTO: Improve interoperability with other undo_marker users") run into another land-mine which caused fallback to conventional recovery to break: 1. Cumulative ACK arrives after FRTO retransmission 2. tcp_try_to_open sees zero retrans_out, clears retrans_stamp which should be kept like in CA_Loss state it would be 3. undo_marker change allowed tcp_packet_delayed to return true because of the cleared retrans_stamp once FRTO is terminated causing LossUndo to occur, which means all loss markings FRTO made are reverted. This means that the conventional recovery basically recovered one loss per RTT, which is not that efficient. It was quite unobvious that the undo_marker change broken something like this, I had a quite long session to track it down because of the non-intuitiviness of the bug (luckily I had a trivial reproducer at hand and I was also able to learn to use kprobes in the process as well :-)). This together with the NewReno+FRTO fix and FRTO in-order workaround this fixes Damon's problems, this and the first mentioned are enough to fix Bugzilla #10063. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Reported-by: Damon L. Chesser <damon@damtek.com> Tested-by: Damon L. Chesser <damon@damtek.com> Tested-by: Sebastian Hyrwall <zibbe@cisko.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Chris Wright <chrisw@sous-sol.org>
2008-06-16tcp: fix skb vs fack_count out-of-sync conditionIlpo Järvinen
[ upstream commit: a6604471db5e7a33474a7f16c64d6b118fae3e74 ] This bug is able to corrupt fackets_out in very rare cases. In order for this to cause corruption: 1) DSACK in the middle of previous SACK block must be generated. 2) In order to take that particular branch, part or all of the DSACKed segment must already be SACKed so that we have that in cache in the first place. 3) The new info must be top enough so that fackets_out will be updated on this iteration. ...then fack_count is updated while skb wasn't, then we walk again that particular segment thus updating fack_count twice for a single skb and finally that value is assigned to fackets_out by tcp_sacktag_one. It is safe to call tcp_sacktag_one just once for a segment (at DSACK), no need to call again for plain SACK. Potential problem of the miscount are limited to premature entry to recovery and to inflated reordering metric (which could even cancel each other out in the most the luckiest scenarios :-)). Both are quite insignificant in worst case too and there exists also code to reset them (fackets_out once sacked_out becomes zero and reordering metric on RTO). This has been reported by a number of people, because it occurred quite rarely, it has been very evasive. Andy Furniss was able to get it to occur couple of times so that a bit more info was collected about the problem using a debug patch, though it still required lot of checking around. Thanks also to others who have tried to help here. This is listed as Bugzilla #10346. The bug was introduced by me in commit 68f8353b48 ([TCP]: Rewrite SACK block processing & sack_recv_cache use), I probably thought back then that there's need to scan that entry twice or didn't dare to make it go through it just once there. Going through twice would have required restoring fack_count after the walk but as noted above, I chose to drop the additional walk step altogether here. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Chris Wright <chrisw@sous-sol.org>
2008-06-16tcp: Limit cwnd growth when deferring for GSOJohn Heffner
[ upstream commit: 246eb2af060fc32650f07203c02bdc0456ad76c7 ] This fixes inappropriately large cwnd growth on sender-limited flows when GSO is enabled, limiting cwnd growth to 64k. [ Backport to 2.6.25 by replacing sk->sk_gso_max_size with 65536 -DaveM ] Signed-off-by: John Heffner <johnwheffner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Chris Wright <chrisw@sous-sol.org>
2008-06-16tcp: Allow send-limited cwnd to grow up to max_burst when gso disabledJohn Heffner
[ upstream commit: ce447eb91409225f8a488f6b7b2a1bdf7b2d884f ] This changes the logic in tcp_is_cwnd_limited() so that cwnd may grow up to tcp_max_burst() even when sk_can_gso() is false, or when sysctl_tcp_tso_win_divisor != 0. Signed-off-by: John Heffner <johnwheffner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Chris Wright <chrisw@sous-sol.org>
2008-06-16tcp: TCP connection times out if ICMP frag needed is delayedSridhar Samudrala
[ upstream commit: 7d227cd235c809c36c847d6a597956ad9e9d2bae ] We are seeing an issue with TCP in handling an ICMP frag needed message that is received after net.ipv4.tcp_retries1 retransmits. The default value of retries1 is 3. So if the path mtu changes and ICMP frag needed is lost for the first 3 retransmits or if it gets delayed until 3 retransmits are done, TCP doesn't update MSS correctly and continues to retransmit the orginal message until it timesout after tcp_retries2 retransmits. I am seeing this issue even with the latest 2.6.25.4 kernel. In tcp_retransmit_timer(), when retransmits counter exceeds tcp_retries1 value, the dst cache entry of the socket is reset. At this time, if we receive an ICMP frag needed message, the dst entry gets updated with the new MTU, but the TCP sockets dst_cache entry remains NULL. So the next time when we try to retransmit after the ICMP frag needed is received, tcp_retransmit_skb() gets called. Here the cur_mss value is calculated at the start of the routine with a NULL sk_dst_cache. Instead we should call tcp_current_mss after the rebuild_header that caches the dst entry with the updated mtu. Also the rebuild_header should be called before tcp_fragment so that skb is fragmented if the mss goes down. Signed-off-by: Sridhar Samudrala <sri@us.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Chris Wright <chrisw@sous-sol.org>
2008-06-16ipsec: Use the correct ip_local_out functionHerbert Xu
[ upstream commit: 1ac06e0306d0192a7a4d9ea1c9e06d355ce7e7d3 ] Because the IPsec output function xfrm_output_resume does its own dst_output call it should always call __ip_local_output instead of ip_local_output as the latter may invoke dst_output directly. Otherwise the return values from nf_hook and dst_output may clash as they both use the value 1 but for different purposes. When that clash occurs this can cause a packet to be used after it has been freed which usually leads to a crash. Because the offending value is only returned from dst_output with qdiscs such as HTB, this bug is normally not visible. Thanks to Marco Berizzi for his perseverance in tracking this down. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Chris Wright <chrisw@sous-sol.org>
2008-06-06asn1: additional sanity checking during BER decoding (CVE-2008-1673)Chris Wright
upstream commit: ddb2c43594f22843e9f3153da151deaba1a834c5 - Don't trust a length which is greater than the working buffer. An invalid length could cause overflow when calculating buffer size for decoding oid. - An oid length of zero is invalid and allows for an off-by-one error when decoding oid because the first subid actually encodes first 2 subids. - A primitive encoding may not have an indefinite length. Thanks to Wei Wang from McAfee for report. Cc: Steven French <sfrench@us.ibm.com> Cc: stable@kernel.org Acked-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-15{nfnetlink, ip, ip6}_queue: fix skb_over_panic when enlarging packetsArnaud Ebalard
[NETFILTER]: {nfnetlink,ip,ip6}_queue: fix skb_over_panic when enlarging packets From: Arnaud Ebalard <arno@natisbad.org> Upstream commit 9a732ed6d: While reinjecting *bigger* modified versions of IPv6 packets using libnetfilter_queue, things work fine on a 2.6.24 kernel (2.6.22 too) but I get the following on recents kernels (2.6.25, trace below is against today's net-2.6 git tree): skb_over_panic: text:c04fddb0 len:696 put:632 head:f7592c00 data:f7592c00 tail:0xf7592eb8 end:0xf7592e80 dev:eth0 ------------[ cut here ]------------ invalid opcode: 0000 [#1] PREEMPT Process sendd (pid: 3657, ti=f6014000 task=f77c31d0 task.ti=f6014000) Stack: c071e638 c04fddb0 000002b8 00000278 f7592c00 f7592c00 f7592eb8 f7592e80 f763c000 f6bc5200 f7592c40 f6015c34 c04cdbfc f6bc5200 00000278 f6015c60 c04fddb0 00000020 f72a10c0 f751b420 00000001 0000000a 000002b8 c065582c Call Trace: [<c04fddb0>] ? nfqnl_recv_verdict+0x1c0/0x2e0 [<c04cdbfc>] ? skb_put+0x3c/0x40 [<c04fddb0>] ? nfqnl_recv_verdict+0x1c0/0x2e0 [<c04fd115>] ? nfnetlink_rcv_msg+0xf5/0x160 [<c04fd03e>] ? nfnetlink_rcv_msg+0x1e/0x160 [<c04fd020>] ? nfnetlink_rcv_msg+0x0/0x160 [<c04f8ed7>] ? netlink_rcv_skb+0x77/0xa0 [<c04fcefc>] ? nfnetlink_rcv+0x1c/0x30 [<c04f8c73>] ? netlink_unicast+0x243/0x2b0 [<c04cfaba>] ? memcpy_fromiovec+0x4a/0x70 [<c04f9406>] ? netlink_sendmsg+0x1c6/0x270 [<c04c8244>] ? sock_sendmsg+0xc4/0xf0 [<c011970d>] ? set_next_entity+0x1d/0x50 [<c0133a80>] ? autoremove_wake_function+0x0/0x40 [<c0118f9e>] ? __wake_up_common+0x3e/0x70 [<c0342fbf>] ? n_tty_receive_buf+0x34f/0x1280 [<c011d308>] ? __wake_up+0x68/0x70 [<c02cea47>] ? copy_from_user+0x37/0x70 [<c04cfd7c>] ? verify_iovec+0x2c/0x90 [<c04c837a>] ? sys_sendmsg+0x10a/0x230 [<c011967a>] ? __dequeue_entity+0x2a/0xa0 [<c011970d>] ? set_next_entity+0x1d/0x50 [<c0345397>] ? pty_write+0x47/0x60 [<c033d59b>] ? tty_default_put_char+0x1b/0x20 [<c011d2e9>] ? __wake_up+0x49/0x70 [<c033df99>] ? tty_ldisc_deref+0x39/0x90 [<c033ff20>] ? tty_write+0x1a0/0x1b0 [<c04c93af>] ? sys_socketcall+0x7f/0x260 [<c0102ff9>] ? sysenter_past_esp+0x6a/0x91 [<c05f0000>] ? snd_intel8x0m_probe+0x270/0x6e0 ======================= Code: 00 00 89 5c 24 14 8b 98 9c 00 00 00 89 54 24 0c 89 5c 24 10 8b 40 50 89 4c 24 04 c7 04 24 38 e6 71 c0 89 44 24 08 e8 c4 46 c5 ff <0f> 0b eb fe 55 89 e5 56 89 d6 53 89 c3 83 ec 0c 8b 40 50 39 d0 EIP: [<c04ccdfc>] skb_over_panic+0x5c/0x60 SS:ESP 0068:f6015bf8 Looking at the code, I ended up in nfq_mangle() function (called by nfqnl_recv_verdict()) which performs a call to skb_copy_expand() due to the increased size of data passed to the function. AFAICT, it should ask for 'diff' instead of 'diff - skb_tailroom(e->skb)'. Because the resulting sk_buff has not enough space to support the skb_put(skb, diff) call a few lines later, this results in the call to skb_over_panic(). The patch below asks for allocation of a copy with enough space for mangled packet and the same amount of headroom as old sk_buff. While looking at how the regression appeared (e2b58a67), I noticed the same pattern in ipq_mangle_ipv6() and ipq_mangle_ipv4(). The patch corrects those locations too. Tested with bigger reinjected IPv6 packets (nfqnl_mangle() path), things are ok (2.6.25 and today's net-2.6 git tree). Signed-off-by: Arnaud Ebalard <arno@natisbad.org> Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-05-15nf_conntrack: padding breaks conntrack hash on ARMPhilip Craig
[NETFILTER]: nf_conntrack: padding breaks conntrack hash on ARM Upstream commit 443a70d50: commit 0794935e "[NETFILTER]: nf_conntrack: optimize hash_conntrack()" results in ARM platforms hashing uninitialised padding. This padding doesn't exist on other architectures. Fix this by replacing NF_CT_TUPLE_U_BLANK() with memset() to ensure everything is initialised. There were only 4 bytes that NF_CT_TUPLE_U_BLANK() wasn't clearing anyway (or 12 bytes on ARM). Signed-off-by: Philip Craig <philipc@snapgear.com> Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-05-15ipvs: fix oops in backup for fwmark conn templatesJulian Anastasov
[ Upstream commit: 2ad17defd596ca7e8ba782d5fc6950ee0e99513c ] Fixes bug http://bugzilla.kernel.org/show_bug.cgi?id=10556 where conn templates with protocol=IPPROTO_IP can oops backup box. Result from ip_vs_proto_get() should be checked because protocol value can be invalid or unsupported in backup. But for valid message we should not fail for templates which use IPPROTO_IP. Also, add checks to validate message limits and connection state. Show state NONE for templates using IPPROTO_IP. Fix tested and confirmed by L0op8ack <l0op8ack@hotmail.com> Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-05-01tcp: tcp_probe buffer overflow and incorrect return valueTom Quetchenbach
[ Upstream commit: 8d390efd903485923419584275fd0c2aa4c94183 ] tcp_probe has a bounds-checking bug that causes many programs (less, python) to crash reading /proc/net/tcp_probe. When it outputs a log line to the reader, it only checks if that line alone will fit in the reader's buffer, rather than that line and all the previous lines it has already written. tcpprobe_read also returns the wrong value if copy_to_user fails--it just passes on the return value of copy_to_user (number of bytes not copied), which makes a failure look like a success. This patch fixes the buffer overflow and sets the return value to -EFAULT if copy_to_user fails. Patch is against latest net-2.6; tested briefly and seems to fix the crashes in less and python. Signed-off-by: Tom Quetchenbach <virtualphtn@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-04-16Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6Linus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: [TCP]: Add return value indication to tcp_prune_ofo_queue(). PS3: gelic: fix the oops on the broken IE returned from the hypervisor b43legacy: fix DMA mapping leakage mac80211: remove message on receiving unexpected unencrypted frames Update rt2x00 MAINTAINERS entry Add rfkill to MAINTAINERS file rfkill: Fix device type check when toggling states b43legacy: Fix usage of struct device used for DMAing ssb: Fix usage of struct device used for DMAing MAINTAINERS: move to generic repository for iwlwifi b43legacy: fix initvals loading on bcm4303 rtl8187: Add missing priv->vif assignments netconsole: only set CON_PRINTBUFFER if the user specifies a netconsole [CAN]: Update documentation of struct sockaddr_can MAINTAINERS: isdn4linux@listserv.isdn4linux.de is subscribers-only [TCP]: Fix never pruned tcp out-of-order queue. [NET_SCHED] sch_api: fix qdisc_tree_decrease_qlen() loop
2008-04-15[TCP]: Add return value indication to tcp_prune_ofo_queue().Vitaliy Gusev
Returns non-zero if tp->out_of_order_queue was seen non-empty. This allows tcp_try_rmem_schedule() to return early. Signed-off-by: Vitaliy Gusev <vgusev@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-15[TCP]: Fix never pruned tcp out-of-order queue.Vitaliy Gusev
tcp_prune_queue() doesn't prune an out-of-order queue at all. Therefore sk_rmem_schedule() can fail but the out-of-order queue isn't pruned . This can lead to tcp deadlock state if the next two conditions are held: 1. There are a sequence hole between last received in order segment and segments enqueued to the out-of-order queue. 2. Size of all segments in the out-of-order queue is more than tcp_mem[2]. Signed-off-by: Vitaliy Gusev <vgusev@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-14Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6Linus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (31 commits) [BRIDGE]: Fix crash in __ip_route_output_key with bridge netfilter [NETFILTER]: ipt_CLUSTERIP: fix race between clusterip_config_find_get and _entry_put [IPV6] ADDRCONF: Don't generate temporary address for ip6-ip6 interface. [IPV6] ADDRCONF: Ensure disabling multicast RS even if privacy extensions are disabled. [IPV6]: Use appropriate sock tclass setting for routing lookup. [IPV6]: IPv6 extension header structures need to be packed. [IPV6]: Fix ipv6 address fetching in raw6_icmp_error(). [NET]: Return more appropriate error from eth_validate_addr(). [ISDN]: Do not validate ISDN net device address prior to interface-up [NET]: Fix kernel-doc for skb_segment [SOCK] sk_stamp: should be initialized to ktime_set(-1L, 0) net: check for underlength tap writes net: make struct tun_struct private to tun.c [SCTP]: IPv4 vs IPv6 addresses mess in sctp_inet[6]addr_event. [SCTP]: Fix compiler warning about const qualifiers [SCTP]: Fix protocol violation when receiving an error lenght INIT-ACK [SCTP]: Add check for hmac_algo parameter in sctp_verify_param() [NET_SCHED] cls_u32: refcounting fix for u32_delete() [DCCP]: Fix skb->cb conflicts with IP [AX25]: Potential ax25_uid_assoc-s leaks on module unload. ...
2008-04-14[NETFILTER]: ipt_CLUSTERIP: fix race between clusterip_config_find_get and ↵Pavel Emelyanov
_entry_put Consider we are putting a clusterip_config entry with the "entries" count == 1, and on the other CPU there's a clusterip_config_find_get in progress: CPU1: CPU2: clusterip_config_entry_put: clusterip_config_find_get: if (atomic_dec_and_test(&c->entries)) { /* true */ read_lock_bh(&clusterip_lock); c = __clusterip_config_find(clusterip); /* found - it's still in list */ ... atomic_inc(&c->entries); read_unlock_bh(&clusterip_lock); write_lock_bh(&clusterip_lock); list_del(&c->list); write_unlock_bh(&clusterip_lock); ... dev_put(c->dev); Oops! We have an entry returned by the clusterip_config_find_get, which is a) not in list b) has a stale dev pointer. The problems will happen when the CPU2 will release the entry - it will remove it from the list for the 2nd time, thus spoiling it, and will put a stale dev pointer. The fix is to make atomic_dec_and_test under the clusterip_lock. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: Patrick McHardy <kaber@trash.net>
2008-04-11Merge branch 'docs' of git://git.lwn.net/linux-2.6Linus Torvalds
* 'docs' of git://git.lwn.net/linux-2.6: Add additional examples in Documentation/spinlocks.txt Move sched-rt-group.txt to scheduler/ Documentation: move rpc-cache.txt to filesystems/ Documentation: move nfsroot.txt to filesystems/ Spell out behavior of atomic_dec_and_lock() in kerneldoc Fix a typo in highres.txt Fixes to the seq_file document Fill out information on patch tags in SubmittingPatches Add the seq_file documentation
2008-04-11Documentation: move nfsroot.txt to filesystems/J. Bruce Fields
Documentation/ is a little large, and filesystems/ seems an obvious place for this file. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2008-04-10[NETNS][IPV6] tcp - assign the netns for timewait socketsDaniel Lezcano
Copy the network namespace from the socket to the timewait socket. Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com> Acked-by: Mark Lord <mlord@pobox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-10[IPV4]: Fix byte value boundary check in do_ip_getsockopt().David S. Miller
This fixes kernel bugzilla 10371. As reported by M.Piechaczek@osmosys.tv, if we try to grab a char sized socket option value, as in: unsigned char ttl = 255; socklen_t len = sizeof(ttl); setsockopt(socket, IPPROTO_IP, IP_MULTICAST_TTL, &ttl, &len); getsockopt(socket, IPPROTO_IP, IP_MULTICAST_TTL, &ttl, &len); The ttl returned will be wrong on big-endian, and on both little- endian and big-endian the next three bytes in userspace are written with garbage. It's because of this test in do_ip_getsockopt(): if (len < sizeof(int) && len > 0 && val>=0 && val<255) { It should allow a 'val' of 255 to pass here, but it doesn't so it copies a full 'int' back to userspace. On little-endian that will write the correct value into the location but it spams on the next three bytes in userspace. On big endian it writes the wrong value into the location and spams the next three bytes. Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-09[NETFILTER]: nf_nat: autoload IPv4 connection trackingJan Engelhardt
Without this patch, the generic L3 tracker would kick in if nf_conntrack_ipv4 was not loaded before nf_nat, which would lead to translation problems with ICMP errors. NAT does not make sense without IPv4 connection tracking anyway, so just add a call to need_ipv4_conntrack(). Signed-off-by: Jan Engelhardt <jengelh@computergmbh.de> Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-07[TCP]: Don't allow FRTO to take place while MTU is being probedIlpo Järvinen
MTU probe can cause some remedies for FRTO because the normal packet ordering may be violated allowing FRTO to make a wrong decision (it might not be that serious threat for anything though). Thus it's safer to not run FRTO while MTU probe is underway. It seems that the basic FRTO variant should also look for an skb at probe_seq.start to check if that's retransmitted one but I didn't implement it now (plain seqno in window check isn't robust against wraparounds). Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-07[TCP]: tcp_simple_retransmit can cause S+LIlpo Järvinen
This fixes Bugzilla #10384 tcp_simple_retransmit does L increment without any checking whatsoever for overflowing S+L when Reno is in use. The simplest scenario I can currently think of is rather complex in practice (there might be some more straightforward cases though). Ie., if mss is reduced during mtu probing, it may end up marking everything lost and if some duplicate ACKs arrived prior to that sacked_out will be non-zero as well, leading to S+L > packets_out, tcp_clean_rtx_queue on the next cumulative ACK or tcp_fastretrans_alert on the next duplicate ACK will fix the S counter. More straightforward (but questionable) solution would be to just call tcp_reset_reno_sack() in tcp_simple_retransmit but it would negatively impact the probe's retransmission, ie., the retransmissions would not occur if some duplicate ACKs had arrived. So I had to add reno sacked_out reseting to CA_Loss state when the first cumulative ACK arrives (this stale sacked_out might actually be the explanation for the reports of left_out overflows in kernel prior to 2.6.23 and S+L overflow reports of 2.6.24). However, this alone won't be enough to fix kernel before 2.6.24 because it is building on top of the commit 1b6d427bb7e ([TCP]: Reduce sacked_out with reno when purging write_queue) to keep the sacked_out from overflowing. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Reported-by: Alessandro Suardi <alessandro.suardi@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-07[TCP]: Fix NewReno's fast rexmit/recovery problems with GSOed skbIlpo Järvinen
Fixes a long-standing bug which makes NewReno recovery crippled. With GSO the whole head skb was marked as LOST which is in violation of NewReno procedure that only wants to mark one packet and ended up breaking our TCP code by causing counter overflow because our code was built on top of assumption about valid NewReno procedure. This manifested as triggering a WARN_ON for the overflow in a number of places. It seems relatively safe alternative to just do nothing if tcp_fragment fails due to oom because another duplicate ACK is likely to be received soon and the fragmentation will be retried. Special thanks goes to Soeren Sonnenburg <kernel@nn7.de> who was lucky enough to be able to reproduce this so that the warning for the overflow was hit. It's not as easy task as it seems even if this bug happens quite often because the amount of outstanding data is pretty significant for the mismarkings to lead to an overflow. Because it's very late in 2.6.25-rc cycle (if this even makes in time), I didn't want to touch anything with SACK enabled here. Fragmenting might be useful for it as well but it's more or less a policy decision rather than mandatory fix. Thus there's no need to rush and we can postpone considering tcp_fragment with SACK for 2.6.26. In 2.6.24 and earlier, this very same bug existed but the effect is slightly different because of a small changes in the if conditions that fit to the patch's context. With them nothing got lost marker and thus no retransmissions happened. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-07[TCP]: Restore 2.6.24 mark_head_lost behavior for newreno/fackIlpo Järvinen
The fast retransmission can be forced locally to the rfc3517 branch in tcp_update_scoreboard instead of making such fragile constructs deeper in tcp_mark_head_lost. This is necessary for the next patch which must not have loopholes for cnt > packets check. As one can notice, readability got some improvements too because of this :-). Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-03[ICMP]: Ensure that ICMP relookup maintains status quoHerbert Xu
The ICMP relookup path is only meant to modify behaviour when appropriate IPsec policies are in place and marked as requiring relookups. It is certainly not meant to modify behaviour when IPsec policies don't exist at all. However, due to an oversight on the error paths existing behaviour may in fact change should one of the relookup steps fail. This patch corrects this by redirecting all errors on relookup failures to the previous code path. That is, if the initial xfrm_lookup let the packet pass, we will stand by that decision should the relookup fail due to an error. This should be safe from a security point-of-view because compliant systems must install a default deny policy so the packet would'nt have passed in that case. Many thanks to Julian Anastasov for pointing out this error. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-31[IP] UDP: Use SEQ_START_TOKEN.YOSHIFUJI Hideaki
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-28[INET]: inet_frag_evictor() must run with BH disabledDavid S. Miller
Based upon a lockdep trace from Dave Jones. Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-28[NET]: Don't send ICMP_FRAG_NEEDED for GSO packetsRusty Russell
Commit 9af3912ec9e30509b76cb376abb65a4d8af27df3 ("[NET] Move DF check to ip_forward") added a new check to send ICMP fragmentation needed for large packets. Unlike the check in ip_finish_output(), it doesn't check for GSO. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-27[NETFILTER]: Replate direct proc_fops assignment with proc_create call.Denis V. Lunev
This elliminates infamous race during module loading when one could lookup proc entry without proc_fops assigned. Signed-off-by: Denis V. Lunev <den@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-27[ESP]: Ensure IV is in linear part of the skb to avoid BUG() due to OOB accessThomas Graf
ESP does not account for the IV size when calling pskb_may_pull() to ensure everything it accesses directly is within the linear part of a potential fragment. This results in a BUG() being triggered when the both the IPv4 and IPv6 ESP stack is fed with an skb where the first fragment ends between the end of the esp header and the end of the IV. This bug was found by Dirk Nehring <dnehring@gmx.net> . Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-26[IPSEC]: Fix BEET outputHerbert Xu
The IPv6 BEET output function is incorrectly including the inner header in the payload to be protected. This causes a crash as the packet doesn't actually have that many bytes for a second header. The IPv4 BEET output on the other hand is broken when it comes to handling an inner IPv6 header since it always assumes an inner IPv4 header. This patch fixes both by making sure that neither BEET output function touches the inner header at all. All access is now done through the protocol-independent cb structure. Two new attributes are added to make this work, the IP header length and the IPv4 option length. They're filled in by the inner mode's output function. Thanks to Joakim Koskela for finding this problem. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-26[ICMP]: Dst entry leak in icmp_send host re-lookup code (v2).Pavel Emelyanov
Commit 8b7817f3a959ed99d7443afc12f78a7e1fcc2063 ([IPSEC]: Add ICMP host relookup support) introduced some dst leaks on error paths: the rt pointer can be forgotten to be put. Fix it bu going to a proper label. Found after net namespace's lo refused to unregister :) Many thanks to Den for valuable help during debugging. Herbert pointed out, that xfrm_lookup() will put the rtable in case of error itself, so the first goto fix is redundant. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: Denis V. Lunev <den@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-24[IPSEC]: Fix inter address family IPsec tunnel handling.Kazunori MIYAZAWA
Signed-off-by: Kazunori MIYAZAWA <kazunori@miyazawa.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-22[IPV4] fib_trie: fix warning from rcu_assign_poingerStephen Hemminger
This gets rid of a warning caused by the test in rcu_assign_pointer. I tried to fix rcu_assign_pointer, but that devolved into a long set of discussions about doing it right that came to no real solution. Since the test in rcu_assign_pointer for constant NULL would never succeed in fib_trie, just open code instead. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-22[TCP]: Let skbs grow over a page on fast peersHerbert Xu
While testing the virtio-net driver on KVM with TSO I noticed that TSO performance with a 1500 MTU is significantly worse compared to the performance of non-TSO with a 16436 MTU. The packet dump shows that most of the packets sent are smaller than a page. Looking at the code this actually is quite obvious as it always stop extending the packet if it's the first packet yet to be sent and if it's larger than the MSS. Since each extension is bound by the page size, this means that (given a 1500 MTU) we're very unlikely to construct packets greater than a page, provided that the receiver and the path is fast enough so that packets can always be sent immediately. The fix is also quite obvious. The push calls inside the loop is just an optimisation so that we don't end up doing all the sending at the end of the loop. Therefore there is no specific reason why it has to do so at MSS boundaries. For TSO, the most natural extension of this optimisation is to do the pushing once the skb exceeds the TSO size goal. This is what the patch does and testing with KVM shows that the TSO performance with a 1500 MTU easily surpasses that of a 16436 MTU and indeed the packet sizes sent are generally larger than 16436. I don't see any obvious downsides for slower peers or connections, but it would be prudent to test this extensively to ensure that those cases don't regress. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-21[IPV4]: Fix null dereference in ip_defragPhil Oester
Been seeing occasional panics in my testing of 2.6.25-rc in ip_defrag. Offending line in ip_defrag is here: net = skb->dev->nd_net where dev is NULL. Bisected the problem down to commit ac18e7509e7df327e30d6e073a787d922eaf211d ([NETNS][FRAGS]: Make the inet_frag_queue lookup work in namespaces). Below patch (idea from Patrick McHardy) fixes the problem for me. Signed-off-by: Phil Oester <kernel@linuxace.com> Acked-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-20[TCP]: Fix shrinking windows with window scalingPatrick McHardy
When selecting a new window, tcp_select_window() tries not to shrink the offered window by using the maximum of the remaining offered window size and the newly calculated window size. The newly calculated window size is always a multiple of the window scaling factor, the remaining window size however might not be since it depends on rcv_wup/rcv_nxt. This means we're effectively shrinking the window when scaling it down. The dump below shows the problem (scaling factor 2^7): - Window size of 557 (71296) is advertised, up to 3111907257: IP 172.2.2.3.33000 > 172.2.2.2.33000: . ack 3111835961 win 557 <...> - New window size of 514 (65792) is advertised, up to 3111907217, 40 bytes below the last end: IP 172.2.2.3.33000 > 172.2.2.2.33000: . 3113575668:3113577116(1448) ack 3111841425 win 514 <...> The number 40 results from downscaling the remaining window: 3111907257 - 3111841425 = 65832 65832 / 2^7 = 514 65832 % 2^7 = 40 If the sender uses up the entire window before it is shrunk, this can have chaotic effects on the connection. When sending ACKs, tcp_acceptable_seq() will notice that the window has been shrunk since tcp_wnd_end() is before tp->snd_nxt, which makes it choose tcp_wnd_end() as sequence number. This will fail the receivers checks in tcp_sequence() however since it is before it's tp->rcv_wup, making it respond with a dupack. If both sides are in this condition, this leads to a constant flood of ACKs until the connection times out. Make sure the window is never shrunk by aligning the remaining window to the window scaling factor. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-20[NETFILTER]: ipt_recent: sanity check hit countDaniel Hokka Zakrisson
If a rule using ipt_recent is created with a hit count greater than ip_pkt_list_tot, the rule will never match as it cannot keep track of enough timestamps. This patch makes ipt_recent refuse to create such rules. With ip_pkt_list_tot's default value of 20, the following can be used to reproduce the problem. nc -u -l 0.0.0.0 1234 & for i in `seq 1 100`; do echo $i | nc -w 1 -u 127.0.0.1 1234; done This limits it to 20 packets: iptables -A OUTPUT -p udp --dport 1234 -m recent --set --name test \ --rsource iptables -A OUTPUT -p udp --dport 1234 -m recent --update --seconds \ 60 --hitcount 20 --name test --rsource -j DROP While this is unlimited: iptables -A OUTPUT -p udp --dport 1234 -m recent --set --name test \ --rsource iptables -A OUTPUT -p udp --dport 1234 -m recent --update --seconds \ 60 --hitcount 21 --name test --rsource -j DROP With the patch the second rule-set will throw an EINVAL. Reported-by: Sean Kennedy <skennedy@vcn.com> Signed-off-by: Daniel Hokka Zakrisson <daniel@hozac.com> Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-17[IPV4]: esp_output() misannotationsAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-17[NET] endianness noise: INADDR_ANYAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-11[TCP]: Prevent sending past receiver window with TSO (at last skb)Ilpo Järvinen
With TSO it was possible to send past the receiver window when the skb to be sent was the last in the write queue while the receiver window is the limiting factor. One can notice that there's a loophole in the tcp_mss_split_point that lacked a receiver window check for the tcp_write_queue_tail() if also cwnd was smaller than the full skb. Noticed by Thomas Gleixner <tglx@linutronix.de> in form of "Treason uncloaked! Peer ... shrinks window .... Repaired." messages (the peer didn't actually shrink its window as the message suggests, we had just sent something past it without a permission to do so). Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Tested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-04[IPCONFIG]: The kernel gets no IP from some DHCP serversStephen Hemminger
From: Stephen Hemminger <shemminger@linux-foundation.org> Based upon a patch by Marcel Wappler: This patch fixes a DHCP issue of the kernel: some DHCP servers (i.e. in the Linksys WRT54Gv5) are very strict about the contents of the DHCPDISCOVER packet they receive from clients. Table 5 in RFC2131 page 36 requests the fields 'ciaddr' and 'siaddr' MUST be set to '0'. These DHCP servers ignore Linux kernel's DHCP discovery packets with these two fields set to '255.255.255.255' (in contrast to popular DHCP clients, such as 'dhclient' or 'udhcpc'). This leads to a not booting system. Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-04[ESP]: Add select on AUTHENCHerbert Xu
Now the ESP uses the AEAD interface even for algorithms which are not combined mode, we need to select CONFIG_CRYPTO_AUTHENC as otherwise only combined mode algorithms will work. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-03-03[TCP]: Must count fack_count also when skippingIlpo Järvinen
It makes fackets_out to grow too slowly compared with the real write queue. This shouldn't cause those BUG_TRAP(packets <= tp->packets_out) to trigger but how knows how such inconsistent fackets_out affects here and there around TCP when everything is nowadays assuming accurate fackets_out. So lets see if this silences them all. Reported by Guillaume Chazarain <guichaz@gmail.com>. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-02-28[TCP]: BIC web page link is corrected.Sangtae Ha
Signed-off-by: Sangtae Ha <sha2@ncsu.edu> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-02-28[IPV4]: Use proc_create() to setup ->proc_fops firstWang Chen
Use proc_create() to make sure that ->proc_fops be setup before gluing PDE to main tree. Signed-off-by: Wang Chen <wangchen@cn.fujitsu.com> Signed-off-by: David S. Miller <davem@davemloft.net>