kernel/include/net/netns/xfrm.h, branch linux-5.11.y

net: xfrm: Localize sequence counter per network namespace

2021-04-14T06:47:16Z

[ Upstream commit e88add19f68191448427a6e4eb059664650a837f ] A sequence counter write section must be serialized or its internal state can get corrupted. The "xfrm_state_hash_generation" seqcount is global, but its write serialization lock (net->xfrm.xfrm_state_lock) is instantiated per network namespace. The write protection is thus insufficient. To provide full protection, localize the sequence counter per network namespace instead. This should be safe as both the seqcount read and write sections access data exclusively within the network namespace. It also lays the foundation for transforming "xfrm_state_hash_generation" data type from seqcount_t to seqcount_LOCKNAME_t in further commits. Fixes: b65e3d7be06f ("xfrm: state: add sequence count to detect hash resizes") Signed-off-by: Ahmed S. Darwish Signed-off-by: Steffen Klassert Signed-off-by: Sasha Levin

xfrm: policy: store inexact policies in an rhashtable

2018-11-09T10:57:47Z

Switch packet-path lookups for inexact policies to rhashtable. In this initial version, we now no longer need to search policies with non-matching address family and type. Next patch will add the if_id as well so lookups from the xfrm interface driver only need to search inexact policies for that device. Future patches will augment the hlist in each rhash bucket with a tree and pre-sort policies according to daddr/prefix. A single rhashtable is used. In order to avoid a full rhashtable walk on netns exit, the bins get placed on a pernet list, i.e. we add almost no cost for network namespaces that had no xfrm policies. The inexact lists are kept in place, and policies are added to both the per-rhash-inexact list and a pernet one. The latter is needed for the control plane to handle migrate -- these requests do not consider the if_id, so if we'd remove the inexact_list now we would have to search all hash buckets and then figure out which matching policy candidate is the most recent one -- this appears a bit harder than just keeping the 'old' inexact list for this purpose. Signed-off-by: Florian Westphal Acked-by: David S. Miller Signed-off-by: Steffen Klassert

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02T10:10:55Z

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 Reviewed-by: Philippe Ombredanne Reviewed-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

xfrm: remove flow cache

2017-07-18T18:13:41Z

After rcu conversions performance degradation in forward tests isn't that noticeable anymore. See next patch for some numbers. A followup patcg could then also remove genid from the policies as we do not cache bundles anymore. Signed-off-by: Florian Westphal Signed-off-by: David S. Miller

xfrm: state: remove per-netns gc task

2016-08-24T11:16:06Z

After commit 5b8ef3415a21f173 ("xfrm: Remove ancient sleeping when the SA is in acquire state") gc does not need any per-netns data anymore. As far as gc is concerned all state structs are the same, so we can use a global work struct for it. Signed-off-by: Florian Westphal Signed-off-by: Steffen Klassert

xfrm: policy: convert policy_lock to spinlock

2016-08-12T06:07:12Z

After earlier patches conversions all spots acquire the writer lock and we can now convert this to a normal spinlock. Signed-off-by: Florian Westphal Signed-off-by: Steffen Klassert

xfrm: policy: make xfrm_policy_lookup_bytype lockless

2016-08-12T06:07:12Z

side effect: no longer disables BH (should be fine). Signed-off-by: Florian Westphal Signed-off-by: Steffen Klassert

xfrm: state: don't use lock anymore unless acquire operation is needed

2016-08-10T09:23:24Z

push the lock down, after earlier patches we can rely on rcu to make sure state struct won't go away. Signed-off-by: Florian Westphal Signed-off-by: Steffen Klassert

flowcache: Avoid OOM condition under preasure

2016-03-17T09:28:42Z

We can hit an OOM condition if we are under presure because we can not free the entries in gc_list fast enough. So add a counter for the not yet freed entries in the gc_list and refuse new allocations if the value is too high. Signed-off-by: Steffen Klassert

xfrm: Do not hash socket policies

2014-11-13T10:25:03Z

Back in 2003 when I added policy expiration, I half-heartedly did a clean-up and renamed xfrm_sk_policy_link/xfrm_sk_policy_unlink to __xfrm_policy_link/__xfrm_policy_unlink, because the latter could be reused for all policies. I never actually got around to using __xfrm_policy_link for non-socket policies. Later on hashing was added to all xfrm policies, including socket policies. In fact, we don't need hashing on socket policies at all since they're always looked up via a linked list. This patch restores xfrm_sk_policy_link/xfrm_sk_policy_unlink as wrappers around __xfrm_policy_link/__xfrm_policy_unlink so that it's obvious we're dealing with socket policies. This patch also removes hashing from __xfrm_policy_link as for now it's only used by socket policies which do not need to be hashed. Ironically this will in fact allow us to use this helper for non-socket policies which I shall do later. Signed-off-by: Herbert Xu Signed-off-by: Steffen Klassert