- 08 Feb, 2015 39 commits
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David S. Miller authored
Neal Cardwellsays: ==================== tcp: mitigate TCP ACK loops due to out-of-window validation dupacks This patch series mitigates "ack loop" DoS scenarios by rate-limiting outgoing duplicate ACKs sent in response to incoming "out of window" segments. Background ----------- There are several cases in which the TCP RFCs specify that a TCP endpoint should send a pure duplicate ACK in response to a pure duplicate ACK that appears to be invalid due to being "out of window": (1) RFC 793 (section 3.9, page 69) specifies that endpoints should send a duplicate ACK in response to an ACK when the incoming sequence number is invalid due to being outside the receive window: "If an incoming segment is not acceptable, an acknowledgment should be sent in reply". (2) RFC 793 (section 3.9, page 72) says: "If the ACK acknowledges something not yet sent (SEG.ACK > SND.NXT) then send an ACK". (3) RFC 1323 (section 4.2.1, page 18) specifies that endpoints should send a duplicate ACK in response to an ACK when the PAWS check for the incoming timestamp value fails: "If .... SEG.TSval < TS.Recent and if TS.Recent is valid ... Send an acknowledgement in reply" The problem ------------ Normally, this is not a problem. However, a buggy middlebox or malicious man-in-the-middle can inject a few packets into the conversation that advance each endpoint's notion of the current window (sequence, ACK, or timestamp), without either side noticing. In this case, from then on each side can think the other is sending invalid segments. Thus an infinite feedback loop of duplicate ACKs can ensue, as each endpoint receives a duplicate ACK, decides that it is invalid (due to sequence number, ACK number, or timestamp), and then sends a dupack in reply, which the other side decides is invalid, responding with a dupack... ad infinitum. This ping-pong feedback loop can happen at a very high rate. This phenomenon can and does happen in practice. It has been seen in datacenter and Internet contexts at Google, and has been documented by Anil Agarwal in the Nov 2013 tcpm thread "TCP mismatched sequence numbers issue", and Avery Fay in the Feb 2015 Linux netdev thread "Invalid timestamp? causing tight ack loop (hundreds of thousands of packets / sec)". This patch series ------------------ This patch series mitigates such ack loops by rate-limiting outgoing duplicate ACKs sent in response to incoming TCP packets that are for an existing connection but that are invalid due to any of the reasons mentioned above: sequence number (1), ACK field (2), or timestamp value (3). The rate limit for such duplicate ACKs is specified by a new sysctl, tcp_invalid_ratelimit, which specifies the minimal space between such outbound duplicate ACKs, in milliseconds. The default is 500 (500ms), and 0 disables the mechanism. We rate-limit these duplicate ACK responses rather than blocking them entirely or resetting the connection, because legitimate connections can rely on dupacks in response to some out-of-window segments. For example, zero window probes are typically sent with a sequence number that is below the current window, and ZWPs thus expect to thus elicit a dupack in response. Testing: this approach has been in use at Google for a while. ==================== Signed-off-by:David S. Miller <davem@davemloft.net>
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Neal Cardwell authored
Ensure that in state FIN_WAIT2 or TIME_WAIT, where the connection is represented by a tcp_timewait_sock, we rate limit dupacks in response to incoming packets (a) with TCP timestamps that fail PAWS checks, or (b) with sequence numbers that are out of the acceptable window. We do not send a dupack in response to out-of-window packets if it has been less than sysctl_tcp_invalid_ratelimit (default 500ms) since we last sent a dupack in response to an out-of-window packet. Reported-by:
Avery Fay <avery@mixpanel.com> Signed-off-by:
Neal Cardwell <ncardwell@google.com> Signed-off-by:
Yuchung Cheng <ycheng@google.com> Signed-off-by:
Eric Dumazet <edumazet@google.com> Signed-off-by:
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Neal Cardwell authored
Ensure that in state ESTABLISHED, where the connection is represented by a tcp_sock, we rate limit dupacks in response to incoming packets (a) with TCP timestamps that fail PAWS checks, or (b) with sequence numbers or ACK numbers that are out of the acceptable window. We do not send a dupack in response to out-of-window packets if it has been less than sysctl_tcp_invalid_ratelimit (default 500ms) since we last sent a dupack in response to an out-of-window packet. There is already a similar (although global) rate-limiting mechanism for "challenge ACKs". When deciding whether to send a challence ACK, we first consult the new per-connection rate limit, and then the global rate limit. Reported-by:
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Neal Cardwell authored
In the SYN_RECV state, where the TCP connection is represented by tcp_request_sock, we now rate-limit SYNACKs in response to a client's retransmitted SYNs: we do not send a SYNACK in response to client SYN if it has been less than sysctl_tcp_invalid_ratelimit (default 500ms) since we last sent a SYNACK in response to a client's retransmitted SYN. This allows the vast majority of legitimate client connections to proceed unimpeded, even for the most aggressive platforms, iOS and MacOS, which actually retransmit SYNs 1-second intervals for several times in a row. They use SYN RTO timeouts following the progression: 1,1,1,1,1,2,4,8,16,32. Reported-by:
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Neal Cardwell authored
Helpers for mitigating ACK loops by rate-limiting dupacks sent in response to incoming out-of-window packets. This patch includes: - rate-limiting logic - sysctl to control how often we allow dupacks to out-of-window packets - SNMP counter for cases where we rate-limited our dupack sending The rate-limiting logic in this patch decides to not send dupacks in response to out-of-window segments if (a) they are SYNs or pure ACKs and (b) the remote endpoint is sending them faster than the configured rate limit. We rate-limit our responses rather than blocking them entirely or resetting the connection, because legitimate connections can rely on dupacks in response to some out-of-window segments. For example, zero window probes are typically sent with a sequence number that is below the current window, and ZWPs thus expect to thus elicit a dupack in response. We allow dupacks in response to TCP segments with data, because these may be spurious retransmissions for which the remote endpoint wants to receive DSACKs. This is safe because segments with data can't realistically be part of ACK loops, which by their nature consist of each side sending pure/data-less ACKs to each other. The dupack interval is controlled by a new sysctl knob, tcp_invalid_ratelimit, given in milliseconds, in case an administrator needs to dial this upward in the face of a high-rate DoS attack. The name and units are chosen to be analogous to the existing analogous knob for ICMP, icmp_ratelimit. The default value for tcp_invalid_ratelimit is 500ms, which allows at most one such dupack per 500ms. This is chosen to be 2x faster than the 1-second minimum RTO interval allowed by RFC 6298 (section 2, rule 2.4). We allow the extra 2x factor because network delay variations can cause packets sent at 1 second intervals to be compressed and arrive much closer. Reported-by:
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Pravin B Shelar authored
Flow alloc needs to initialize unmasked key pointer. Otherwise it can crash kernel trying to free random unmasked-key pointer. general protection fault: 0000 [#1] SMP 3.19.0-rc6-net-next+ #457 Hardware name: Supermicro X7DWU/X7DWU, BIOS 1.1 04/30/2008 RIP: 0010:[<ffffffff8111df0e>] [<ffffffff8111df0e>] kfree+0xac/0x196 Call Trace: [<ffffffffa060bd87>] flow_free+0x21/0x59 [openvswitch] [<ffffffffa060bde0>] ovs_flow_free+0x21/0x23 [openvswitch] [<ffffffffa0605b4a>] ovs_packet_cmd_execute+0x2f3/0x35f [openvswitch] [<ffffffffa0605995>] ? ovs_packet_cmd_execute+0x13e/0x35f [openvswitch] [<ffffffff811fe6fb>] ? nla_parse+0x4f/0xec [<ffffffff8139a2fc>] genl_family_rcv_msg+0x26d/0x2c9 [<ffffffff8107620f>] ? __lock_acquire+0x90e/0x9aa [<ffffffff8139a3be>] genl_rcv_msg+0x66/0x89 [<ffffffff8139a358>] ? genl_family_rcv_msg+0x2c9/0x2c9 [<ffffffff81399591>] netlink_rcv_skb+0x3e/0x95 [<ffffffff81399898>] ? genl_rcv+0x18/0x37 [<ffffffff813998a7>] genl_rcv+0x27/0x37 [<ffffffff81399033>] netlink_unicast+0x103/0x191 [<ffffffff81399382>] netlink_sendmsg+0x2c1/0x310 [<ffffffff811007ad>] ? might_fault+0x50/0xa0 [<ffffffff8135c773>] do_sock_sendmsg+0x5f/0x7a [<ffffffff8135c799>] sock_sendmsg+0xb/0xd [<ffffffff8135cacf>] ___sys_sendmsg+0x1a3/0x218 [<ffffffff8113e54b>] ? get_close_on_exec+0x86/0x86 [<ffffffff8115a9d0>] ? fsnotify+0x32c/0x348 [<ffffffff8115a720>] ? fsnotify+0x7c/0x348 [<ffffffff8113e5f5>] ? __fget+0xaa/0xbf [<ffffffff8113e54b>] ? get_close_on_exec+0x86/0x86 [<ffffffff8135cccd>] __sys_sendmsg+0x3d/0x5e [<ffffffff8135cd02>] SyS_sendmsg+0x14/0x16 [<ffffffff81411852>] system_call_fastpath+0x12/0x17 Fixes: 74ed7ab9("openvswitch: Add support for unique flow IDs.") CC: Joe Stringer <joestringer@nicira.com> Reported-by:
Or Gerlitz <ogerlitz@mellanox.com> Signed-off-by:
Pravin B Shelar <pshelar@nicira.com> Acked-by:
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David S. Miller authored
Hariprasad Shenai says: ==================== Add support to dump some hw debug info This patch series adds support to dump sensor info, dump Transport Processor event trace, dump Upper Layer Protocol RX module command trace, dump mailbox contents and dump Transport Processor congestion control configuration. Will send a separate patch series for all the hw stats patches, by moving them to ethtool. The patches series is created against 'net-next' tree. And includes patches on cxgb4 driver. We have included all the maintainers of respective drivers. Kindly review the change and let us know in case of any review comments. V2: Dopped all hw stats related patches. Added a new patch which adds support to dump congestion control table. ==================== Signed-off-by: -
Hariprasad Shenai authored
Dump Transport Processor modules congestion control configuration Signed-off-by:
Hariprasad Shenai <hariprasad@chelsio.com> Signed-off-by:
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Hariprasad Shenai authored
Adds support to dump the current contents of mailbox and the driver which owns it. Signed-off-by:
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Hariprasad Shenai authored
Dump Upper Layer Protocol RX module command trace Signed-off-by:
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Hariprasad Shenai authored
Dump Transport Processor event trace. Signed-off-by:
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Hariprasad Shenai authored
Dump out various chip sensor information. Currently Chip Temperature and Core Voltage. Signed-off-by:
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David S. Miller authored
Sathya Perla says: ==================== be2net: patch set Hi Dave, pls consider applying the following patch-set to the net-next tree. It has 5 code/style cleanup patches and 4 patches that add functionality to the driver. Patch 1 moves routines that were not needed to be in be.h to the respective src files, to avoid unnecessary compilation. Patch 2 replaces (1 << x) with BIT(x) macro Patch 3 refactors code that checks if a FW flash file is compatible with the adapter. The code is now refactored into 2 routines, the first one gets the file type from the image file and the 2nd routine checks if the file type is compatible with the adapter. Patch 4 adds compatibility checks for flashing a FW image on the new Skyhawk P2 HW revision. Patch 5 adds support for a new "offset based" flashing scheme, wherein the driver informs the FW of the offset at which each component in the flash file is to be flashed at. This helps flashing components that were previously not recognized by the running FW. Patch 6 simplifies the be_cmd_rx_filter() routine, by passing to it the filter flags already used in the FW cmd, instead of the netdev flags that were converted to the FW-cmd flags. Patch 7 introduces helper routines in be_set_rx_mode() and be_vid_config() to improve code readability. Patch 8 adds processing of port-misconfig async event sent by the FW. Patch 9 removes unnecessary swapping of a field in the TX desc. ==================== Signed-off-by: -
Sathya Perla authored
The 32-bit fields of a tx-wrb are little endian. The driver is currently using be_dws_le_to_cpu() routine to swap (cpu to le) all the fields of a tx-wrb. So, the rsvd field is also unnecessarily swapped. This patch fixes this by individually swapping the required fields. Also, the type of the fields in eth_tx_wrb{} is now changed to __le32 from u32 to avoid sparse warnings. Signed-off-by:Sathya Perla <sathya.perla@emulex.com> Signed-off-by:
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Vasundhara Volam authored
This patch adds support for processing the port misconfigure async event generated by the FW. This event is generated typically when an optical module is incorrectly installed or is faulty. This patch also moves the port_name field to the adapter struct for logging the event. As the be_cmd_query_port_name() call is now moved to be_get_config(), it is modified to use the mailbox instead of MCCQ Signed-off-by:
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Sathya Perla authored
This patch re-factors the filter setting (uc-list, mc-list, promisc, vlan) code in be_set_rx_mode() and be_vid_config() to make it more readable and reduce code duplication. This patch adds a separate field to track the state/mode of filtering, along with moving all the filtering related fields to one place in be be_adapter structure. Signed-off-by:
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Sathya Perla authored
This patch passes BE_IF_FLAGS_XXX flags to be_cmd_rx_filter() routine instead of the IFF_XXX flags. Doing this gets rid of the code to convert the IFF_XXX flags to the BE_IF_FLAGS_XXX used by the FW cmd. The patch also removes code for setting if_flags_mask that was duplicated for each filter mode. Signed-off-by:
Kalesh AP <kalesh.purayil@emulex.com> Signed-off-by:
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Vasundhara Volam authored
While sending FW update cmds to the FW, the driver specifies the "type" of each component that needs to be flashed. The FW then picks the offset in the flash area at which the componnet is to be flashed. This doesn't work when new components that the current FW doesn't recognize, need to be flashed. Recent FWs (10.2 and above) support a scheme of FW-update wherein the "offset" of the component in the flash area can be specified instead of the "type". This patch uses the "offset" based FW-update mechanism and only when it fails, it fallsback to the old "type" based update. Signed-off-by:
Vasundhara Volam <vasundhara.volam@emulex.com> Signed-off-by:
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Vasundhara Volam authored
Skyhawk-B0 FW UFI is not compatible to flash on Skyhawk-P2 ASIC. But, Skyhawk-P2 FW UFI is compatible with both B0 and P2 chips. Signed-off-by:
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Vasundhara Volam authored
This patch re-factors the code that checks for flash file compatibility with the chip type, for better readability, as follows: - be_get_ufi_type() returns the UFI type from the flash file - be_check_ufi_compatibility() checks if the UFI type is compatible with the adapter/chip that is being flashed Signed-off-by:
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Vasundhara Volam authored
BIT(x) is the preffered usage. Signed-off-by:
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Sathya Perla authored
Routines that are called only inside one src file must remain in that file itself. Including them in a header file that is used for exporting routine/struct definitions, causes unnecessary compilation of other src files, when such a routine is modified. Signed-off-by:
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Roopa Prabhu authored
This patch fixes a missing bridge port check caught by smatch. setlink/dellink of attributes like vlans can come for a bridge device and there is no need to offload those today. So, this patch adds a bridge port check. (In these cases however, the BRIDGE_SELF flags will always be set and we may not hit a problem with the current code). smatch complaint: The patch 68e331c7: "bridge: offload bridge port attributes to switch asic if feature flag set" from Jan 29, 2015, leads to the following Smatch complaint: net/bridge/br_netlink.c:552 br_setlink() error: we previously assumed 'p' could be null (see line 518) net/bridge/br_netlink.c 517 518 if (p && protinfo) { ^ Check for NULL. Reported-By:
Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by:
Roopa Prabhu <roopa@cumulusnetworks.com> Signed-off-by:
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git://git.kernel.org/pub/scm/linux/kernel/git/jkirsher/net-nextDavid S. Miller authored
Jeff Kirsher says: ==================== Intel Wired LAN Driver Updates 2015-02-05 This series contains updates to fm10k, ixgbe and ixgbevf. Matthew fixes an issue where fm10k does not properly drop the upper-most four bits on of the VLAN ID due to type promotion, so resolve the issue by not masking off the bits, but by throwing an error if the VLAN ID is out-of-bounds. Then cleans up two cases where variables were not being used, but were being set, so just remove the unused variables. Don cleans up sparse errors in the x550 family file for ixgbe. Fixed up a redundant setting of the default value for set_rxpba, which was done twice accidentally. Cleaned up the probe routine to remove a redundant attempt to identify the PHY, which could lead to a panic on x550. Added support for VXLAN receive checksum offload in x550 hardware. Added the Ethertype Anti-spoofing feature for affected devices. Emil enables ixgbe and ixgbevf to allow multiple queues in SRIOV mode. Adds RSS support for x550 per VF. Fixed up a couple of issues introduced in commit 2b509c0c ("ixgbe: cleanup ixgbe_ndo_set_vf_vlan"), fixed setting of the VLAN inside ixgbe_enable_port_vlan() and disable the "hide VLAN" bit in PFQDE when port VLAN is disabled. Cleaned up the setting of vlan_features by enabling all features at once. Fixed the ordering of the shutdown patch so that we attempt to shutdown the rings more gracefully. We shutdown the main Rx filter in the case of Rx and we set the carrier_off state in the case of Tx so that packets stop being delivered from outside the driver. Then we shutdown interrupts and NAPI, then finally stop the rings from performing DMA and clean them. Added code to allow for Tx hang checking to provide more robust debug info in the event of a transmit unit hang in ixgbevf. Cleaned up ixgbevf logic dealing with link up/down by breaking down the link detection and up/down events into separate functions, similar to how these events are handled in other drivers. Combined the ixgbevf reset and watchdog tasks into a single task so that we can avoid multiple schedules of the reset task when we have a reset event needed due to either the mailbox going down or transmit packets being present on a link down. v2: Fixed up patch #03 of the series to remove the variable type change based on feedback from David Laight ==================== Signed-off-by:
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David S. Miller authored
Hayes Wang says: ==================== r8152: adjust the code V2: Correct the subject of patch #5. Replace "link feed" with "line feed". v1: Code adjustment. ==================== Signed-off-by: -
hayeswang authored
Use BIT macro to replace (1 << bits). Signed-off-by:
Hayes Wang <hayeswang@realtek.com> Signed-off-by:
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hayeswang authored
vlan_get_protocol() has been defined and use it to replace get_protocol(). Signed-off-by:
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hayeswang authored
Keep NETIF_F_HW_VLAN_CTAG_RX and NETIF_F_HW_VLAN_CTAG_TX at the same line. Signed-off-by:
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hayeswang authored
It is unnecessary to accress the hw register if the device is unplugged. Signed-off-by:
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hayeswang authored
Replace (tp->speed & LINK_STATUS) with netif_carrier_ok(). Signed-off-by:
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hayeswang authored
Set LPM timer to 500us, except for RTL_VER_04 which doesn't link at USB 3.0. Signed-off-by:
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hayeswang authored
If a error occurs when submitting rx, skip the remaining submissions and try to submit them again next time. Signed-off-by:
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Sowmini Varadhan authored
Commit 083735f4 ("rds: switch rds_message_copy_from_user() to iov_iter") breaks rds_message_copy_from_user() semantics on success, and causes it to return nbytes copied, when it should return 0. This commit fixes that bug. Signed-off-by:
Sowmini Varadhan <sowmini.varadhan@oracle.com> Signed-off-by:
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Rasmus Villemoes authored
The macro rdsdebug is defined as pr_debug("%s(): " fmt, __func__ , ##args) Hence it doesn't make sense to include the name of the calling function explicitly in the format string passed to rdsdebug. Signed-off-by:Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by:
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Jarno Rajahalme authored
OVS userspace already probes the openvswitch kernel module for OVS_ACTION_ATTR_SET_MASKED support. This patch adds the kernel module implementation of masked set actions. The existing set action sets many fields at once. When only a subset of the IP header fields, for example, should be modified, all the IP fields need to be exact matched so that the other field values can be copied to the set action. A masked set action allows modification of an arbitrary subset of the supported header bits without requiring the rest to be matched. Masked set action is now supported for all writeable key types, except for the tunnel key. The set tunnel action is an exception as any input tunnel info is cleared before action processing starts, so there is no tunnel info to mask. The kernel module converts all (non-tunnel) set actions to masked set actions. This makes action processing more uniform, and results in less branching and duplicating the action processing code. When returning actions to userspace, the fully masked set actions are converted back to normal set actions. We use a kernel internal action code to be able to tell the userspace provided and converted masked set actions apart. Signed-off-by:
Jarno Rajahalme <jrajahalme@nicira.com> Acked-by:
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David S. Miller authored
Florian Fainelli says: ==================== net: dsa: bcm_sf2: GPHY power down This patch series implement GPHY power up and down in the SF2 switch driver in order to conserve power whenever possible (e.g: port is brought down or unused during Wake-on-LAN). ==================== Signed-off-by: -
Florian Fainelli authored
Implement the power on/off recommended procedure for the Single GPHY we have on our Starfighter 2 switch. In order to make sure we get proper LED link/activity signaling during suspend, switch the link indication from the Switch/MAC to the PHY. Finally, since the GPHY needs to be reset to be put in low power mode, we will loose any context applied to it: workarounds, EEE etc.. so we need to call phy_init_hw() to get our fixups re-applied successfully. Signed-off-by:
Florian Fainelli <f.fainelli@gmail.com> Signed-off-by:
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Florian Fainelli authored
Move the code that touches the single GPHY register from bcm_sf2_sw_resume() to a separate function since we will have to enable/disable the GPHY from different locations, and we want the code to be self-contained. Signed-off-by:
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git://git.kernel.org/pub/scm/linux/kernel/git/sameo/nfc-nextDavid S. Miller authored
NFC: 3.20 second pull request This is the second NFC pull request for 3.20. It brings: - NCI NFCEE (NFC Execution Environment, typically an embedded or external secure element) discovery and enabling/disabling support. In order to communicate with an NFCEE, we also added NCI's logical connections support to the NCI stack. - HCI over NCI protocol support. Some secure elements only understand HCI and thus we need to send them HCI frames when they're part of an NCI chipset. - NFC_EVT_TRANSACTION userspace API addition. Whenever an application running on a secure element needs to notify its host counterpart, we send an NFC_EVENT_SE_TRANSACTION event to userspace through the NFC netlink socket. - Secure element and HCI transaction event support for the st21nfcb chipset. Signed-off-by:
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- 06 Feb, 2015 1 commit
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Thomas Graf authored
The remove logic properly searched the remaining chain for a matching entry with an identical hash but it did this while searching from both the old and new table. Instead in order to not leave stale references behind we need to: 1. When growing and searching from the new table: Search remaining chain for entry with same hash to avoid having the new table directly point to a entry with a different hash. 2. When shrinking and searching from the old table: Check if the element after the removed would create a cross reference and avoid it if so. These bugs were present from the beginning in nft_hash. Also, both insert functions calculated the hash based on the mask of the new table. This worked while growing. Wwhile shrinking, the mask of the inew table is smaller than the mask of the old table. This lead to a bit not being taken into account when selecting the bucket lock and thus caused the wrong bucket to be locked eventually. Fixes: 7e1e7763 ("lib: Resizable, Scalable, Concurrent Hash Table") Fixes: 97defe1e ("rhashtable: Per bucket locks & deferred expansion/shrinking") Reported-by:Ying Xue <ying.xue@windriver.com> Signed-off-by:
Thomas Graf <tgraf@suug.ch> Signed-off-by:
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