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2021-07-21ipv6: ioam: Data plane support for Pre-allocated TraceJustin Iurman1-0/+19
Implement support for processing the IOAM Pre-allocated Trace with IPv6, see [1] and [2]. Introduce a new IPv6 Hop-by-Hop TLV option, see IANA [3]. A new per-interface sysctl is introduced. The value is a boolean to accept (=1) or ignore (=0, by default) IPv6 IOAM options on ingress for an interface: - net.ipv6.conf.XXX.ioam6_enabled Two other sysctls are introduced to define IOAM IDs, represented by an integer. They are respectively per-namespace and per-interface: - net.ipv6.ioam6_id - net.ipv6.conf.XXX.ioam6_id The value of the first one represents the IOAM ID of the node itself (u32; max and default value = U32_MAX>>8, due to hop limit concatenation) while the other represents the IOAM ID of an interface (u16; max and default value = U16_MAX). Each "ioam6_id" sysctl has a "_wide" equivalent: - net.ipv6.ioam6_id_wide - net.ipv6.conf.XXX.ioam6_id_wide The value of the first one represents the wide IOAM ID of the node itself (u64; max and default value = U64_MAX>>8, due to hop limit concatenation) while the other represents the wide IOAM ID of an interface (u32; max and default value = U32_MAX). The use of short and wide equivalents is not exclusive, a deployment could choose to leverage both. For example, net.ipv6.conf.XXX.ioam6_id (short format) could be an identifier for a physical interface, whereas net.ipv6.conf.XXX.ioam6_id_wide (wide format) could be an identifier for a logical sub-interface. Documentation about new sysctls is provided at the end of this patchset. Two relativistic hash tables are used: one for IOAM namespaces, the other for IOAM schemas. A namespace can only have a single active schema and a schema can only be attached to a single namespace (1:1 relationship). [1] https://tools.ietf.org/html/draft-ietf-ippm-ioam-ipv6-options [2] https://tools.ietf.org/html/draft-ietf-ippm-ioam-data [3] https://www.iana.org/assignments/ipv6-parameters/ipv6-parameters.xhtml#ipv6-parameters-2 Signed-off-by: Justin Iurman <justin.iurman@uliege.be> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-05-19net: Add notifications when multipath hash field changeIdo Schimmel1-1/+17
In-kernel notifications are already sent when the multipath hash policy itself changes, but not when the multipath hash fields change. Add these notifications, so that interested listeners (e.g., switch ASIC drivers) could perform the necessary configuration. Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: Petr Machata <petrm@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-05-18ipv6: Add custom multipath hash policyIdo Schimmel1-1/+2
Add a new multipath hash policy where the packet fields used for hash calculation are determined by user space via the fib_multipath_hash_fields sysctl that was introduced in the previous patch. The current set of available packet fields includes both outer and inner fields, which requires two invocations of the flow dissector. Avoid unnecessary dissection of the outer or inner flows by skipping dissection if none of the outer or inner fields are required. In accordance with the existing policies, when an skb is not available, packet fields are extracted from the provided flow key. In which case, only outer fields are considered. Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-05-18ipv6: Add a sysctl to control multipath hash fieldsIdo Schimmel1-0/+12
A subsequent patch will add a new multipath hash policy where the packet fields used for multipath hash calculation are determined by user space. This patch adds a sysctl that allows user space to set these fields. The packet fields are represented using a bitmask and are common between IPv4 and IPv6 to allow user space to use the same numbering across both protocols. For example, to hash based on standard 5-tuple: # sysctl -w net.ipv6.fib_multipath_hash_fields=0x0037 net.ipv6.fib_multipath_hash_fields = 0x0037 To avoid introducing holes in 'struct netns_sysctl_ipv6', move the 'bindv6only' field after the multipath hash fields. The kernel rejects unknown fields, for example: # sysctl -w net.ipv6.fib_multipath_hash_fields=0x1000 sysctl: setting key "net.ipv6.fib_multipath_hash_fields": Invalid argument Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-01ipv6: convert elligible sysctls to u8Eric Dumazet1-20/+18
Convert most sysctls that can fit in a byte. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-02-09IPv6: Extend 'fib_notify_on_flag_change' sysctlAmit Cohen1-1/+1
Add the value '2' to 'fib_notify_on_flag_change' to allow sending notifications only for failed route installation. Separate value is added for such notifications because there are less of them, so they do not impact performance and some users will find them more important. Signed-off-by: Amit Cohen <amcohen@nvidia.com> Signed-off-by: Ido Schimmel <idosch@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-02-03net: ipv6: Emit notification when fib hardware flags are changedAmit Cohen1-0/+9
After installing a route to the kernel, user space receives an acknowledgment, which means the route was installed in the kernel, but not necessarily in hardware. The asynchronous nature of route installation in hardware can lead to a routing daemon advertising a route before it was actually installed in hardware. This can result in packet loss or mis-routed packets until the route is installed in hardware. It is also possible for a route already installed in hardware to change its action and therefore its flags. For example, a host route that is trapping packets can be "promoted" to perform decapsulation following the installation of an IPinIP/VXLAN tunnel. Emit RTM_NEWROUTE notifications whenever RTM_F_OFFLOAD/RTM_F_TRAP flags are changed. The aim is to provide an indication to user-space (e.g., routing daemons) about the state of the route in hardware. Introduce a sysctl that controls this behavior. Keep the default value at 0 (i.e., do not emit notifications) for several reasons: - Multiple RTM_NEWROUTE notification per-route might confuse existing routing daemons. - Convergence reasons in routing daemons. - The extra notifications will negatively impact the insertion rate. - Not all users are interested in these notifications. Move fib6_info_hw_flags_set() to C file because it is no longer a short function. Signed-off-by: Amit Cohen <amcohen@nvidia.com> Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-09-03ipv6: Fix sysctl max for fib_multipath_hash_policyIdo Schimmel1-1/+2
Cited commit added the possible value of '2', but it cannot be set. Fix it by adjusting the maximum value to '2'. This is consistent with the corresponding IPv4 sysctl. Before: # sysctl -w net.ipv6.fib_multipath_hash_policy=2 sysctl: setting key "net.ipv6.fib_multipath_hash_policy": Invalid argument net.ipv6.fib_multipath_hash_policy = 2 # sysctl net.ipv6.fib_multipath_hash_policy net.ipv6.fib_multipath_hash_policy = 0 After: # sysctl -w net.ipv6.fib_multipath_hash_policy=2 net.ipv6.fib_multipath_hash_policy = 2 # sysctl net.ipv6.fib_multipath_hash_policy net.ipv6.fib_multipath_hash_policy = 2 Fixes: d8f74f0975d8 ("ipv6: Support multipath hashing on inner IP pkts") Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: Stephen Suryaputra <ssuryaextr@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-27sysctl: pass kernel pointers to ->proc_handlerChristoph Hellwig1-2/+1
Instead of having all the sysctl handlers deal with user pointers, which is rather hairy in terms of the BPF interaction, copy the input to and from userspace in common code. This also means that the strings are always NUL-terminated by the common code, making the API a little bit safer. As most handler just pass through the data to one of the common handlers a lot of the changes are mechnical. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Andrey Ignatov <rdna@fb.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-03-04ipv6: Use math to point per net sysctls into the appropriate struct netCambda Zhu1-17/+4
The data pointers of ipv6 sysctl are set one by one which is hard to maintain, especially with kconfig. This patch simplifies it by using math to point the per net sysctls into the appropriate struct net, just like what we did for ipv4. Signed-off-by: Cambda Zhu <cambda@linux.alibaba.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-19proc/sysctl: add shared variables for range checkMatteo Croce1-6/+4
In the sysctl code the proc_dointvec_minmax() function is often used to validate the user supplied value between an allowed range. This function uses the extra1 and extra2 members from struct ctl_table as minimum and maximum allowed value. On sysctl handler declaration, in every source file there are some readonly variables containing just an integer which address is assigned to the extra1 and extra2 members, so the sysctl range is enforced. The special values 0, 1 and INT_MAX are very often used as range boundary, leading duplication of variables like zero=0, one=1, int_max=INT_MAX in different source files: $ git grep -E '\.extra[12].*&(zero|one|int_max)' |wc -l 248 Add a const int array containing the most commonly used values, some macros to refer more easily to the correct array member, and use them instead of creating a local one for every object file. This is the bloat-o-meter output comparing the old and new binary compiled with the default Fedora config: # scripts/bloat-o-meter -d vmlinux.o.old vmlinux.o add/remove: 2/2 grow/shrink: 0/2 up/down: 24/-188 (-164) Data old new delta sysctl_vals - 12 +12 __kstrtab_sysctl_vals - 12 +12 max 14 10 -4 int_max 16 - -16 one 68 - -68 zero 128 28 -100 Total: Before=20583249, After=20583085, chg -0.00% [mcroce@redhat.com: tipc: remove two unused variables] Link: http://lkml.kernel.org/r/20190530091952.4108-1-mcroce@redhat.com [akpm@linux-foundation.org: fix net/ipv6/sysctl_net_ipv6.c] [arnd@arndb.de: proc/sysctl: make firmware loader table conditional] Link: http://lkml.kernel.org/r/20190617130014.1713870-1-arnd@arndb.de [akpm@linux-foundation.org: fix fs/eventpoll.c] Link: http://lkml.kernel.org/r/20190430180111.10688-1-mcroce@redhat.com Signed-off-by: Matteo Croce <mcroce@redhat.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Kees Cook <keescook@chromium.org> Reviewed-by: Aaron Tomlin <atomlin@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-07-02net/ipv6: Fix misuse of proc_dointvec "flowlabel_reflect"Eiichi Tsukata1-1/+1
/proc/sys/net/ipv6/flowlabel_reflect assumes written value to be in the range of 0 to 3. Use proc_dointvec_minmax instead of proc_dointvec. Fixes: 323a53c41292 ("ipv6: tcp: enable flowlabel reflection in some RST packets") Signed-off-by: Eiichi Tsukata <devel@etsukata.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-01ipv6: icmp: allow flowlabel reflection in echo repliesEric Dumazet1-2/+2
Extend flowlabel_reflect bitmask to allow conditional reflection of incoming flowlabels in echo replies. Note this has precedence against auto flowlabels. Add flowlabel_reflect enum to replace hard coded values. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-06ipv6: tcp: enable flowlabel reflection in some RST packetsEric Dumazet1-0/+3
When RST packets are sent because no socket could be found, it makes sense to use flowlabel_reflect sysctl to decide if a reflection of the flowlabel is requested. This extends commit 22b6722bfa59 ("ipv6: Add sysctl for per namespace flow label reflection"), for some TCP RST packets. In order to provide full control of this new feature, flowlabel_reflect becomes a bitmask. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-25ipv6: sr: Compute flowlabel for outer IPv6 header of seg6 encap modeAhmed Abdelsalam1-0/+8
ECMP (equal-cost multipath) hashes are typically computed on the packets' 5-tuple(src IP, dst IP, src port, dst port, L4 proto). For encapsulated packets, the L4 data is not readily available and ECMP hashing will often revert to (src IP, dst IP). This will lead to traffic polarization on a single ECMP path, causing congestion and waste of network capacity. In IPv6, the 20-bit flow label field is also used as part of the ECMP hash. In the lack of L4 data, the hashing will be on (src IP, dst IP, flow label). Having a non-zero flow label is thus important for proper traffic load balancing when L4 data is unavailable (i.e., when packets are encapsulated). Currently, the seg6_do_srh_encap() function extracts the original packet's flow label and set it as the outer IPv6 flow label. There are two issues with this behaviour: a) There is no guarantee that the inner flow label is set by the source. b) If the original packet is not IPv6, the flow label will be set to zero (e.g., IPv4 or L2 encap). This patch adds a function, named seg6_make_flowlabel(), that computes a flow label from a given skb. It supports IPv6, IPv4 and L2 payloads, and leverages the per namespace 'seg6_flowlabel" sysctl value. The currently support behaviours are as follows: -1 set flowlabel to zero. 0 copy flowlabel from Inner paceket in case of Inner IPv6 (Set flowlabel to 0 in case IPv4/L2) 1 Compute the flowlabel using seg6_make_flowlabel() This patch has been tested for IPv6, IPv4, and L2 traffic. Signed-off-by: Ahmed Abdelsalam <amsalam20@gmail.com> Acked-by: David Lebrun <dlebrun@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-27net: Drop pernet_operations::asyncKirill Tkhai1-1/+0
Synchronous pernet_operations are not allowed anymore. All are asynchronous. So, drop the structure member. Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-04net/ipv6: Add support for path selection using hash of 5-tupleDavid Ahern1-0/+27
Some operators prefer IPv6 path selection to use a standard 5-tuple hash rather than just an L3 hash with the flow the label. To that end add support to IPv6 for multipath hash policy similar to bf4e0a3db97eb ("net: ipv4: add support for ECMP hash policy choice"). The default is still L3 which covers source and destination addresses along with flow label and IPv6 protocol. Signed-off-by: David Ahern <dsahern@gmail.com> Reviewed-by: Ido Schimmel <idosch@mellanox.com> Tested-by: Ido Schimmel <idosch@mellanox.com> Reviewed-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-19net: Convert ipv6_sysctl_net_opsKirill Tkhai1-0/+1
These pernet_operations create and destroy sysctl tables. They are not touched by another net pernet_operations. So, it's possible to execute them in parallel with others. Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-04Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-0/+1
Files removed in 'net-next' had their license header updated in 'net'. We take the remove from 'net-next'. Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-03ipv6: Implement limits on Hop-by-Hop and Destination optionsTom Herbert1-0/+32
RFC 8200 (IPv6) defines Hop-by-Hop options and Destination options extension headers. Both of these carry a list of TLVs which is only limited by the maximum length of the extension header (2048 bytes). By the spec a host must process all the TLVs in these options, however these could be used as a fairly obvious denial of service attack. I think this could in fact be a significant DOS vector on the Internet, one mitigating factor might be that many FWs drop all packets with EH (and obviously this is only IPv6) so an Internet wide attack might not be so effective (yet!). By my calculation, the worse case packet with TLVs in a standard 1500 byte MTU packet that would be processed by the stack contains 1282 invidual TLVs (including pad TLVS) or 724 two byte TLVs. I wrote a quick test program that floods a whole bunch of these packets to a host and sure enough there is substantial time spent in ip6_parse_tlv. These packets contain nothing but unknown TLVS (that are ignored), TLV padding, and bogus UDP header with zero payload length. 25.38% [kernel] [k] __fib6_clean_all 21.63% [kernel] [k] ip6_parse_tlv 4.21% [kernel] [k] __local_bh_enable_ip 2.18% [kernel] [k] ip6_pol_route.isra.39 1.98% [kernel] [k] fib6_walk_continue 1.88% [kernel] [k] _raw_write_lock_bh 1.65% [kernel] [k] dst_release This patch adds configurable limits to Destination and Hop-by-Hop options. There are three limits that may be set: - Limit the number of options in a Hop-by-Hop or Destination options extension header. - Limit the byte length of a Hop-by-Hop or Destination options extension header. - Disallow unrecognized options in a Hop-by-Hop or Destination options extension header. The limits are set in corresponding sysctls: ipv6.sysctl.max_dst_opts_cnt ipv6.sysctl.max_hbh_opts_cnt ipv6.sysctl.max_dst_opts_len ipv6.sysctl.max_hbh_opts_len If a max_*_opts_cnt is less than zero then unknown TLVs are disallowed. The number of known TLVs that are allowed is the absolute value of this number. If a limit is exceeded when processing an extension header the packet is dropped. Default values are set to 8 for options counts, and set to INT_MAX for maximum length. Note the choice to limit options to 8 is an arbitrary guess (roughly based on the fact that the stack supports three HBH options and just one destination option). These limits have being proposed in draft-ietf-6man-rfc6434-bis. Tested (by Martin Lau) I tested out 1 thread (i.e. one raw_udp process). I changed the net.ipv6.max_dst_(opts|hbh)_number between 8 to 2048. With sysctls setting to 2048, the softirq% is packed to 100%. With 8, the softirq% is almost unnoticable from mpstat. v2; - Code and documention cleanup. - Change references of RFC2460 to be RFC8200. - Add reference to RFC6434-bis where the limits will be in standard. Signed-off-by: Tom Herbert <tom@quantonium.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman1-0/+1
Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-25ipv6: Add sysctl for per namespace flow label reflectionJakub Sitnicki1-0/+8
Reflecting IPv6 Flow Label at server nodes is useful in environments that employ multipath routing to load balance the requests. As "IPv6 Flow Label Reflection" standard draft [1] points out - ICMPv6 PTB error messages generated in response to a downstream packets from the server can be routed by a load balancer back to the original server without looking at transport headers, if the server applies the flow label reflection. This enables the Path MTU Discovery past the ECMP router in load-balance or anycast environments where each server node is reachable by only one path. Introduce a sysctl to enable flow label reflection per net namespace for all newly created sockets. Same could be earlier achieved only per socket by setting the IPV6_FL_F_REFLECT flag for the IPV6_FLOWLABEL_MGR socket option. [1] https://tools.ietf.org/html/draft-wang-6man-flow-label-reflection-01 Signed-off-by: Jakub Sitnicki <jkbs@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-27calipso: Add a label cache.Huw Davies1-0/+19
This works in exactly the same way as the CIPSO label cache. The idea is to allow the lsm to cache the result of a secattr lookup so that it doesn't need to perform the lookup for every skbuff. It introduces two sysctl controls: calipso_cache_enable - enables/disables the cache. calipso_cache_bucket_size - sets the size of a cache bucket. Signed-off-by: Huw Davies <huw@codeweavers.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
2015-08-01ipv6: Implement different admin modes for automatic flow labelsTom Herbert1-1/+6
Change the meaning of net.ipv6.auto_flowlabels to provide a mode for automatic flow labels generation. There are four modes: 0: flow labels are disabled 1: flow labels are enabled, sockets can opt-out 2: flow labels are allowed, sockets can opt-in 3: flow labels are enabled and enforced, no opt-out for sockets np->autoflowlabel is initialized according to the sysctl value. Signed-off-by: Tom Herbert <tom@herbertland.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-10ipv6: Nonlocal bindTom Herbert1-0/+8
Add support to allow non-local binds similar to how this was done for IPv4. Non-local binds are very useful in emulating the Internet in a box, etc. This add the ip_nonlocal_bind sysctl under ipv6. Testing: Set up nonlocal binding and receive routing on a host, e.g.: ip -6 rule add from ::/0 iif eth0 lookup 200 ip -6 route add local 2001:0:0:1::/64 dev lo proto kernel scope host table 200 sysctl -w net.ipv6.ip_nonlocal_bind=1 Set up routing to 2001:0:0:1::/64 on peer to go to first host ping6 -I 2001:0:0:1::1 peer-address -- to verify Signed-off-by: Tom Herbert <tom@herbertland.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-04ipv6: Flow label state rangesTom Herbert1-0/+8
This patch divides the IPv6 flow label space into two ranges: 0-7ffff is reserved for flow label manager, 80000-fffff will be used for creating auto flow labels (per RFC6438). This only affects how labels are set on transmit, it does not affect receive. This range split can be disbaled by systcl. Background: IPv6 flow labels have been an unmitigated disappointment thus far in the lifetime of IPv6. Support in HW devices to use them for ECMP is lacking, and OSes don't turn them on by default. If we had these we could get much better hashing in IPv6 networks without resorting to DPI, possibly eliminating some of the motivations to to define new encaps in UDP just for getting ECMP. Unfortunately, the initial specfications of IPv6 did not clarify how they are to be used. There has always been a vague concept that these can be used for ECMP, flow hashing, etc. and we do now have a good standard how to this in RFC6438. The problem is that flow labels can be either stateful or stateless (as in RFC6438), and we are presented with the possibility that a stateless label may collide with a stateful one. Attempts to split the flow label space were rejected in IETF. When we added support in Linux for RFC6438, we could not turn on flow labels by default due to this conflict. This patch splits the flow label space and should give us a path to enabling auto flow labels by default for all IPv6 packets. This is an API change so we need to consider compatibility with existing deployment. The stateful range is chosen to be the lower values in hopes that most uses would have chosen small numbers. Once we resolve the stateless/stateful issue, we can proceed to look at enabling RFC6438 flow labels by default (starting with scaled testing). Signed-off-by: Tom Herbert <tom@herbertland.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-31ipv6: coding style: comparison for equality with NULLIan Morris1-1/+1
The ipv6 code uses a mixture of coding styles. In some instances check for NULL pointer is done as x == NULL and sometimes as !x. !x is preferred according to checkpatch and this patch makes the code consistent by adopting the latter form. No changes detected by objdiff. Signed-off-by: Ian Morris <ipm@chirality.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-24ipv6: introduce idgen_delay and idgen_retries knobsHannes Frederic Sowa1-0/+16
This is specified by RFC 7217. Cc: Erik Kline <ek@google.com> Cc: Fernando Gont <fgont@si6networks.com> Cc: Lorenzo Colitti <lorenzo@google.com> Cc: YOSHIFUJI Hideaki/吉藤英明 <hideaki.yoshifuji@miraclelinux.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-05ipv6: add sysctl_mld_qrv to configure query robustness variableHannes Frederic Sowa1-0/+10
This patch adds a new sysctl_mld_qrv knob to configure the mldv1/v2 query robustness variable. It specifies how many retransmit of unsolicited mld retransmit should happen. Admins might want to tune this on lossy links. Also reset mld state on interface down/up, so we pick up new sysctl settings during interface up event. IPv6 certification requests this knob to be available. I didn't make this knob netns specific, as it is mostly a setting in a physical environment and should be per host. Cc: Flavio Leitner <fbl@redhat.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Acked-by: Flavio Leitner <fbl@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-06Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-0/+1
Conflicts: drivers/net/Makefile net/ipv6/sysctl_net_ipv6.c Two ipv6_table_template[] additions overlap, so the index of the ipv6_table[x] assignments needed to be adjusted. In the drivers/net/Makefile case, we've gotten rid of the garbage whereby we had to list every single USB networking driver in the top-level Makefile, there is just one "USB_NETWORKING" that guards everything. Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-03ipv6: data of fwmark_reflect sysctl needs to be updated on netns constructionHannes Frederic Sowa1-0/+1
Fixes: e110861f86094cd ("net: add a sysctl to reflect the fwmark on replies") Cc: Lorenzo Colitti <lorenzo@google.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-08ipv6: Implement automatic flow label generation on transmitTom Herbert1-0/+8
Automatically generate flow labels for IPv6 packets on transmit. The flow label is computed based on skb_get_hash. The flow label will only automatically be set when it is zero otherwise (i.e. flow label manager hasn't set one). This supports the transmit side functionality of RFC 6438. Added an IPv6 sysctl auto_flowlabels to enable/disable this behavior system wide, and added IPV6_AUTOFLOWLABEL socket option to enable this functionality per socket. By default, auto flowlabels are disabled to avoid possible conflicts with flow label manager, however if this feature proves useful we may want to enable it by default. It should also be noted that FreeBSD has already implemented automatic flow labels (including the sysctl and socket option). In FreeBSD, automatic flow labels default to enabled. Performance impact: Running super_netperf with 200 flows for TCP_RR and UDP_RR for IPv6. Note that in UDP case, __skb_get_hash will be called for every packet with explains slight regression. In the TCP case the hash is saved in the socket so there is no regression. Automatic flow labels disabled: TCP_RR: 86.53% CPU utilization 127/195/322 90/95/99% latencies 1.40498e+06 tps UDP_RR: 90.70% CPU utilization 118/168/243 90/95/99% latencies 1.50309e+06 tps Automatic flow labels enabled: TCP_RR: 85.90% CPU utilization 128/199/337 90/95/99% latencies 1.40051e+06 UDP_RR 92.61% CPU utilization 115/164/236 90/95/99% latencies 1.4687e+06 Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-14net: add a sysctl to reflect the fwmark on repliesLorenzo Colitti1-0/+7
Kernel-originated IP packets that have no user socket associated with them (e.g., ICMP errors and echo replies, TCP RSTs, etc.) are emitted with a mark of zero. Add a sysctl to make them have the same mark as the packet they are replying to. This allows an administrator that wishes to do so to use mark-based routing, firewalling, etc. for these replies by marking the original packets inbound. Tested using user-mode linux: - ICMP/ICMPv6 echo replies and errors. - TCP RST packets (IPv4 and IPv6). Signed-off-by: Lorenzo Colitti <lorenzo@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-20ipv6: add flowlabel_consistency sysctlFlorent Fourcot1-0/+8
With the introduction of IPV6_FL_F_REFLECT, there is no guarantee of flow label unicity. This patch introduces a new sysctl to protect the old behaviour, enable by default. Changelog of V3: * rename ip6_flowlabel_consistency to flowlabel_consistency * use net_info_ratelimited() * checkpatch cleanups Signed-off-by: Florent Fourcot <florent.fourcot@enst-bretagne.fr> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-15IPv6: move the anycast_src_echo_reply sysctl to netns_sysctl_ipv6FX Le Bail1-2/+2
This change move anycast_src_echo_reply sysctl with other ipv6 sysctls. Suggested-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: Francois-Xavier Le Bail <fx.lebail@yahoo.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-08IPv6: add the option to use anycast addresses as source addresses in echo replyFX Le Bail1-0/+8
This change allows to follow a recommandation of RFC4942. - Add "anycast_src_echo_reply" sysctl to control the use of anycast addresses as source addresses for ICMPv6 echo reply. This sysctl is false by default to preserve existing behavior. - Add inline check ipv6_anycast_destination(). - Use them in icmpv6_echo_reply(). Reference: RFC4942 - IPv6 Transition/Coexistence Security Considerations (http://tools.ietf.org/html/rfc4942#section-2.1.6) 2.1.6. Anycast Traffic Identification and Security [...] To avoid exposing knowledge about the internal structure of the network, it is recommended that anycast servers now take advantage of the ability to return responses with the anycast address as the source address if possible. Signed-off-by: Francois-Xavier Le Bail <fx.lebail@yahoo.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-13net: Convert uses of typedef ctl_table to struct ctl_tableJoe Perches1-2/+2
Reduce the uses of this unnecessary typedef. Done via perl script: $ git grep --name-only -w ctl_table net | \ xargs perl -p -i -e '\ sub trim { my ($local) = @_; $local =~ s/(^\s+|\s+$)//g; return $local; } \ s/\b(?<!struct\s)ctl_table\b(\s*\*\s*|\s+\w+)/"struct ctl_table " . trim($1)/ge' Reflow the modified lines that now exceed 80 columns. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-21net: Delete all remaining instances of ctl_pathEric W. Biederman1-7/+0
We don't use struct ctl_path anymore so delete the exported constants. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-21net ipv6: Don't use sysctl tables with .child entries.Eric W. Biederman1-24/+23
The sysctl core no longer natively understands sysctl tables with .child entries. Split the ipv6_table to remove the .child entries. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-21net ipv6: Remove unneded registration of an empty net/ipv6/neighEric W. Biederman1-27/+0
sysctl no longer requires explicit creation of directories. The neigh directory is always populated with at least a default entry so this should cause no user visible changes. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-21net: Move all of the network sysctls without a namespace into init_net.Eric W. Biederman1-1/+1
This makes it clearer which sysctls are relative to your current network namespace. This makes it a little less error prone by not exposing sysctls for the initial network namespace in other namespaces. This is the same way we handle all of our other network interfaces to userspace and I can't honestly remember why we didn't do this for sysctls right from the start. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-21net: Kill register_sysctl_rotableEric W. Biederman1-1/+1
register_sysctl_rotable never caught on as an interesting way to register sysctls. My take on the situation is that what we want are sysctls that we can only see in the initial network namespace. What we have implemented with register_sysctl_rotable are sysctls that we can see in all of the network namespaces and can only change in the initial network namespace. That is a very silly way to go. Just register the network sysctls in the initial network namespace and we don't have any weird special cases to deal with. The sysctls affected are: /proc/sys/net/ipv4/ipfrag_secret_interval /proc/sys/net/ipv4/ipfrag_max_dist /proc/sys/net/ipv6/ip6frag_secret_interval /proc/sys/net/ipv6/mld_max_msf I really don't expect anyone will miss them if they can't read them in a child user namespace. CC: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-01net: Add export.h for EXPORT_SYMBOL/THIS_MODULE to non-modulesPaul Gortmaker1-0/+1
These files are non modular, but need to export symbols using the macros now living in export.h -- call out the include so that things won't break when we remove the implicit presence of module.h from everywhere. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-03-22net ipv6: Fix duplicate /proc/sys/net/ipv6/neigh directory entries.Eric W. Biederman1-7/+11
When I was fixing issues with unregisgtering tables under /proc/sys/net/ipv6/neigh by adding a mount point it appears I missed a critical ordering issue, in the ipv6 initialization. I had not realized that ipv6_sysctl_register is called at the very end of the ipv6 initialization and in particular after we call neigh_sysctl_register from ndisc_init. "neigh" needs to be initialized in ipv6_static_sysctl_register which is the first ipv6 table to initialized, and definitely before ndisc_init. This removes the weirdness of duplicate tables while still providing a "neigh" mount point which prevents races in sysctl unregistering. This was initially reported at https://bugzilla.kernel.org/show_bug.cgi?id=31232 Reported-by: sunkan@zappa.cx Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2011-02-01net: Fix ipv6 neighbour unregister_sysctl_table warningEric W. Biederman1-1/+8
In my testing of 2.6.37 I was occassionally getting a warning about sysctl table entries being unregistered in the wrong order. Digging in it turns out this dates back to the last great sysctl reorg done where Al Viro introduced the requirement that sysctl directories needed to be created before and destroyed after the files in them. It turns out that in that great reorg /proc/sys/net/ipv6/neigh was overlooked. So this patch fixes that oversight and makes an annoying warning message go away. >------------[ cut here ]------------ >WARNING: at kernel/sysctl.c:1992 unregister_sysctl_table+0x134/0x164() >Pid: 23951, comm: kworker/u:3 Not tainted 2.6.37-350888.2010AroraKernelBeta.fc14.x86_64 #1 >Call Trace: > [<ffffffff8103e034>] warn_slowpath_common+0x80/0x98 > [<ffffffff8103e061>] warn_slowpath_null+0x15/0x17 > [<ffffffff810452f8>] unregister_sysctl_table+0x134/0x164 > [<ffffffff810e7834>] ? kfree+0xc4/0xd1 > [<ffffffff813439b2>] neigh_sysctl_unregister+0x22/0x3a > [<ffffffffa02cd14e>] addrconf_ifdown+0x33f/0x37b [ipv6] > [<ffffffff81331ec2>] ? skb_dequeue+0x5f/0x6b > [<ffffffffa02ce4a5>] addrconf_notify+0x69b/0x75c [ipv6] > [<ffffffffa02eb953>] ? ip6mr_device_event+0x98/0xa9 [ipv6] > [<ffffffff813d2413>] notifier_call_chain+0x32/0x5e > [<ffffffff8105bdea>] raw_notifier_call_chain+0xf/0x11 > [<ffffffff8133cdac>] call_netdevice_notifiers+0x45/0x4a > [<ffffffff8133d2b0>] rollback_registered_many+0x118/0x201 > [<ffffffff8133d3af>] unregister_netdevice_many+0x16/0x6d > [<ffffffff8133d571>] default_device_exit_batch+0xa4/0xb8 > [<ffffffff81337c42>] ? cleanup_net+0x0/0x194 > [<ffffffff81337a2a>] ops_exit_list+0x4e/0x56 > [<ffffffff81337d36>] cleanup_net+0xf4/0x194 > [<ffffffff81053318>] process_one_work+0x187/0x280 > [<ffffffff8105441b>] worker_thread+0xff/0x19f > [<ffffffff8105431c>] ? worker_thread+0x0/0x19f > [<ffffffff8105776d>] kthread+0x7d/0x85 > [<ffffffff81003824>] kernel_thread_helper+0x4/0x10 > [<ffffffff810576f0>] ? kthread+0x0/0x85 > [<ffffffff81003820>] ? kernel_thread_helper+0x0/0x10 >---[ end trace 8a7e9310b35e9486 ]--- Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo1-0/+1
implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-01-18net: spread __net_init, __net_exitAlexey Dobriyan1-2/+2
__net_init/__net_exit are apparently not going away, so use them to full extent. In some cases __net_init was removed, because it was called from __net_exit code. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-11-12sysctl net: Remove unused binary sysctl codeEric W. Biederman1-8/+4
Now that sys_sysctl is a compatiblity wrapper around /proc/sys all sysctl strategy routines, and all ctl_name and strategy entries in the sysctl tables are unused, and can be revmoed. In addition neigh_sysctl_register has been modified to no longer take a strategy argument and it's callers have been modified not to pass one. Cc: "David Miller" <davem@davemloft.net> Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org> Cc: netdev@vger.kernel.org Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2009-08-02inet6: functions shadow global variableGerrit Renker1-2/+2
This renames away a variable clash: * ipv6_table[] is declared as a static global table; * ipv6_sysctl_net_init() uses ipv6_table to refer/destroy dynamic memory; * ipv6_sysctl_net_exit() also uses ipv6_table for the same purpose; * both the two last functions call kfree() on ipv6_table. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-08remove lots of double-semicolonsFernando Carrijo1-1/+1
Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Acked-by: Theodore Ts'o <tytso@mit.edu> Acked-by: Mark Fasheh <mfasheh@suse.com> Acked-by: David S. Miller <davem@davemloft.net> Cc: James Morris <jmorris@namei.org> Acked-by: Casey Schaufler <casey@schaufler-ca.com> Acked-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>