Steffen Klassert says:
====================
pull request (net): ipsec 2021-08-04
1) Fix a sysbot reported memory leak in xfrm_user_rcv_msg.
From Pavel Skripkin.
2) Revert "xfrm: policy: Read seqcount outside of rcu-read side
in xfrm_policy_lookup_bytype". This commit tried to fix a
lockin bug, but only cured some of the symptoms. A proper
fix is applied on top of this revert.
3) Fix a locking bug on xfrm state hash resize. A recent change
on sequence counters accidentally repaced a spinlock by a mutex.
Fix from Frederic Weisbecker.
4) Fix possible user-memory-access in xfrm_user_rcv_msg_compat().
From Dmitry Safonov.
5) Add initialiation sefltest fot xfrm_spdattr_type_t.
From Dmitry Safonov.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
xfrm_bydst_resize() calls synchronize_rcu() while holding
hash_resize_mutex. But then on PREEMPT_RT configurations,
xfrm_policy_lookup_bytype() may acquire that mutex while running in an
RCU read side critical section. This results in a deadlock.
In fact the scope of hash_resize_mutex is way beyond the purpose of
xfrm_policy_lookup_bytype() to just fetch a coherent and stable policy
for a given destination/direction, along with other details.
The lower level net->xfrm.xfrm_policy_lock, which among other things
protects per destination/direction references to policy entries, is
enough to serialize and benefit from priority inheritance against the
write side. As a bonus, it makes it officially a per network namespace
synchronization business where a policy table resize on namespace A
shouldn't block a policy lookup on namespace B.
Fixes: 77cc278f7b (xfrm: policy: Use sequence counters with associated lock)
Cc: stable@vger.kernel.org
Cc: Ahmed S. Darwish <a.darwish@linutronix.de>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Varad Gautam <varad.gautam@suse.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
When creating new states with seq set in xfrm_usersa_info, we walk
through all the states already installed in that netns to find a
matching ACQUIRE state (__xfrm_find_acq_byseq, called from
xfrm_state_add). This causes severe slowdowns on systems with a large
number of states.
This patch introduces a hashtable using x->km.seq as key, so that the
corresponding state can be found in a reasonable time.
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
A sequence counter write section must be serialized or its internal
state can get corrupted. A plain seqcount_t does not contain the
information of which lock must be held to guaranteee write side
serialization.
For xfrm_state_hash_generation, use seqcount_spinlock_t instead of plain
seqcount_t. This allows to associate the spinlock used for write
serialization with the sequence counter. It thus enables lockdep to
verify that the write serialization lock is indeed held before entering
the sequence counter write section.
If lockdep is disabled, this lock association is compiled out and has
neither storage size nor runtime overhead.
Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
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: b65e3d7be0 ("xfrm: state: add sequence count to detect hash resizes")
Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
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 <fw@strlen.de>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
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>
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 <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
After commit 5b8ef3415a
("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 <fw@strlen.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
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 <fw@strlen.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
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 <fw@strlen.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
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 <steffen.klassert@secunet.com>
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 <herbert@gondor.apana.org.au>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Enable to specify local and remote prefix length thresholds for the
policy hash table via a netlink XFRM_MSG_NEWSPDINFO message.
prefix length thresholds are specified by XFRMA_SPD_IPV4_HTHRESH and
XFRMA_SPD_IPV6_HTHRESH optional attributes (struct xfrmu_spdhthresh).
example:
struct xfrmu_spdhthresh thresh4 = {
.lbits = 0;
.rbits = 24;
};
struct xfrmu_spdhthresh thresh6 = {
.lbits = 0;
.rbits = 56;
};
struct nlmsghdr *hdr;
struct nl_msg *msg;
msg = nlmsg_alloc();
hdr = nlmsg_put(msg, NL_AUTO_PORT, NL_AUTO_SEQ, XFRMA_SPD_IPV4_HTHRESH, sizeof(__u32), NLM_F_REQUEST);
nla_put(msg, XFRMA_SPD_IPV4_HTHRESH, sizeof(thresh4), &thresh4);
nla_put(msg, XFRMA_SPD_IPV6_HTHRESH, sizeof(thresh6), &thresh6);
nla_send_auto(sk, msg);
The numbers are the policy selector minimum prefix lengths to put a
policy in the hash table.
- lbits is the local threshold (source address for out policies,
destination address for in and fwd policies).
- rbits is the remote threshold (destination address for out
policies, source address for in and fwd policies).
The default values are:
XFRMA_SPD_IPV4_HTHRESH: 32 32
XFRMA_SPD_IPV6_HTHRESH: 128 128
Dynamic re-building of the SPD is performed when the thresholds values
are changed.
The current thresholds can be read via a XFRM_MSG_GETSPDINFO request:
the kernel replies to XFRM_MSG_GETSPDINFO requests by an
XFRM_MSG_NEWSPDINFO message, with both attributes
XFRMA_SPD_IPV4_HTHRESH and XFRMA_SPD_IPV6_HTHRESH.
Signed-off-by: Christophe Gouault <christophe.gouault@6wind.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
The idea is an extension of the current policy hashing.
Today only non-prefixed policies are stored in a hash table. This
patch relaxes the constraints, and hashes policies whose prefix
lengths are greater or equal to a configurable threshold.
Each hash table (one per direction) maintains its own set of IPv4 and
IPv6 thresholds (dbits4, sbits4, dbits6, sbits6), by default (32, 32,
128, 128).
Example, if the output hash table is configured with values (16, 24,
56, 64):
ip xfrm policy add dir out src 10.22.0.0/20 dst 10.24.1.0/24 ... => hashed
ip xfrm policy add dir out src 10.22.0.0/16 dst 10.24.1.1/32 ... => hashed
ip xfrm policy add dir out src 10.22.0.0/16 dst 10.24.0.0/16 ... => unhashed
ip xfrm policy add dir out \
src 3ffe:304:124:2200::/60 dst 3ffe:304:124:2401::/64 ... => hashed
ip xfrm policy add dir out \
src 3ffe:304:124:2200::/56 dst 3ffe:304:124:2401::2/128 ... => hashed
ip xfrm policy add dir out \
src 3ffe:304:124:2200::/56 dst 3ffe:304:124:2400::/56 ... => unhashed
The high order bits of the addresses (up to the threshold) are used to
compute the hash key.
Signed-off-by: Christophe Gouault <christophe.gouault@6wind.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
It is not legal to create multiple kmem_cache having the same name.
flowcache can use a single kmem_cache, no need for a per netns
one.
Fixes: ca925cf153 ("flowcache: Make flow cache name space aware")
Reported-by: Jakub Kicinski <moorray3@wp.pl>
Tested-by: Jakub Kicinski <moorray3@wp.pl>
Tested-by: Fan Du <fan.du@windriver.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We currently cache socket policy bundles at xfrm_policy_sk_bundles.
These cached bundles are never used. Instead we create and cache
a new one whenever xfrm_lookup() is called on a socket policy.
Most protocols cache the used routes to the socket, so let's
remove the unused caching of socket policy bundles in xfrm.
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Inserting a entry into flowcache, or flushing flowcache should be based
on per net scope. The reason to do so is flushing operation from fat
netns crammed with flow entries will also making the slim netns with only
a few flow cache entries go away in original implementation.
Since flowcache is tightly coupled with IPsec, so it would be easier to
put flow cache global parameters into xfrm namespace part. And one last
thing needs to do is bumping flow cache genid, and flush flow cache should
also be made in per net style.
Signed-off-by: Fan Du <fan.du@windriver.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
We now queue packets to the policy if the states are not yet resolved,
this replaces the ancient sleeping code. Also the sleeping can cause
indefinite task hangs if the needed state does not get resolved.
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
By semantics, xfrm layer is fully name space aware,
so will the locks, e.g. xfrm_state/pocliy_lock.
Ensure exclusive access into state/policy link list
for different name space with one global lock is not
right in terms of semantics aspect at first place,
as they are indeed mutually independent with each
other, but also more seriously causes scalability
problem.
One practical scenario is on a Open Network Stack,
more than hundreds of lxc tenants acts as routers
within one host, a global xfrm_state/policy_lock
becomes the bottleneck. But onces those locks are
decoupled in a per-namespace fashion, locks contend
is just with in specific name space scope, without
causing additional SPD/SAD access delay for other
name space.
Also this patch improve scalability while as without
changing original xfrm behavior.
Signed-off-by: Fan Du <fan.du@windriver.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Instead of testing defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In a network bench, I noticed an unfortunate false sharing between
'loopback_dev' and 'count' fields in "struct net".
'count' is written each time a socket is created or destroyed, while
loopback_dev might be often read in routing code.
Move loopback_dev in a read mostly section of "struct net"
Note: struct netns_xfrm is cache line aligned on SMP.
(It contains a "struct dst_ops")
Move it at the end to avoid holes, and reduce sizeof(struct net) by 128
bytes on ia32.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
GC is non-existent in netns, so after you hit GC threshold, no new
dst entries will be created until someone triggers cleanup in init_net.
Make xfrm4_dst_ops and xfrm6_dst_ops per-netns.
This is not done in a generic way, because it woule waste
(AF_MAX - 2) * sizeof(struct dst_ops) bytes per-netns.
Reorder GC threshold initialization so it'd be done before registering
XFRM policies.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
xfrm.nlsk is provided by the xfrm_user module and is access via rcu from
other parts of the xfrm code. Add xfrm.nlsk_stash a copy of xfrm.nlsk that
will never be set to NULL. This allows the synchronize_net and
netlink_kernel_release to be deferred until a whole batch of xfrm.nlsk sockets
have been set to NULL.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Make
net.core.xfrm_aevent_etime
net.core.xfrm_acq_expires
net.core.xfrm_aevent_rseqth
net.core.xfrm_larval_drop
sysctls per-netns.
For that make net_core_path[] global, register it to prevent two
/proc/net/core antries and change initcall position -- xfrm_init() is called
from fs_initcall, so this one should be fs_initcall at least.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Per-netns hashes are independently resizeable.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Disallow spurious wakeups in __xfrm_lookup().
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
State GC is per-netns, and this is part of it.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
km_waitq is going to be made per-netns to disallow spurious wakeups
in __xfrm_lookup().
To not wakeup after every garbage-collected xfrm_state (which potentially
can be from different netns) make state GC list per-netns.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
All of this is implicit passing which netns's hashes should be resized.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since hashtables are per-netns, they can be independently resized.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is done to get
a) simple "something leaked" check
b) cover possible DoSes when other netns puts many, many xfrm_states
onto a list.
c) not miss "alien xfrm_state" check in some of list iterators in future.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
