Commit Graph

77 Commits

Author SHA1 Message Date
Pavel Emelyanov efb3cb428d inet_diag: Split inet_diag_get_exact into parts
Similar to previous patch: the 1st part locks the inet handler
and will get generalized and the 2nd one dumps icsk-s and will
be used by TCP and DCCP handlers.

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-09 14:14:08 -05:00
Pavel Emelyanov 476f7dbff3 inet_diag: Split inet_diag_get_exact into parts
The 1st part locks the inet handler and the 2nd one dump the
inet connection sock.

In the next patches the 1st part will be generalized to call
the socket dumping routine indirectly (i.e. TCP/UDP/DCCP) and
the 2nd part will be used by TCP and DCCP handlers.

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-09 14:14:08 -05:00
Pavel Emelyanov b005ab4ef8 inet_diag: Export inet diag cookie checking routine
The netlink diag susbsys stores sk address bits in the nl message
as a "cookie" and uses one when dumps details about particular
socket.

The same will be required for udp diag module, so introduce a heler
in inet_diag module

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-09 14:14:08 -05:00
Pavel Emelyanov 87c22ea52e inet_diag: Reduce the number of args for bytecode run routine
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-09 14:14:07 -05:00
Pavel Emelyanov 7b35eadd7e inet_diag: Remove indirect sizeof from inet diag handlers
There's an info_size value stored on inet_diag_handler, but for existing
code this value is effectively constant, so just use sizeof(struct tcp_info)
where required.

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-09 14:14:07 -05:00
Pavel Emelyanov 8ef874bfc7 sock_diag: Move the sock_ code to net/core/
This patch moves the sock_ code from inet_diag.c to generic sock_diag.c
file and provides necessary request_module-s calls and a pointer on
inet_diag_compat dumping routine.

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-06 13:58:02 -05:00
Pavel Emelyanov a029fe26b6 inet_diag: Cleanup type2proto last user
Now all the code works with sock_diag_req-compatible structs, so it's
possible to stop using the inet_diag_type2proto in inet_csk_diag_fill.
Pass the inet_diag_req into it and use the sdiag_protocol field. At the
same time remove the explicit ext argument, since it's also on the req.

However, this conversion is still required in _compat code, so just move
this routine, not remove.

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-06 13:58:02 -05:00
Pavel Emelyanov d23deaa07b inet_diag: Introduce socket family checks
The new API will specify family to work with. Teach the existing
socket walking code to bypass not interesting ones.

To preserve compatibility with existing behavior the _compat code
sets interesting family to AF_UNSPEC to dump them all.

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-06 13:58:02 -05:00
Pavel Emelyanov 25c4cd2b6d inet_diag: Switch the _dump to work with new header
Make inet_diag_dumo work with given header instead of calculating
one from the nl message.

The SOCK_DIAG_BY_FAMILY just passes skb's one through, the compat code
converts the old header to new one.

Also fix the bytecode calculation to find one at proper offset.

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-06 13:58:02 -05:00
Pavel Emelyanov fe50ce2846 inet_diag: Switch the _get_exact to work with new header
Make inet_diag_get_exact work with given header instead of calculating
one from the nl message.

The SOCK_DIAG_BY_FAMILY just passes skb's one through, the compat code
converts the old header to new one.

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-06 13:58:01 -05:00
Pavel Emelyanov 126fdc3249 inet_diag: Introduce new inet_diag_req header
This one coinsides with the sock_diag_req in the beginning and
contains only used fields from its previous analogue.

The existing code is patched to use the _compat version of it
for now.

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-06 13:58:01 -05:00
Pavel Emelyanov d366477a52 sock_diag: Initial skeleton
When receiving the SOCK_DIAG_BY_FAMILY message we have to find the
handler for provided family and pass the nl message to it.

This patch describes an infrastructure to work with such nandlers
and implements stubs for AF_INET(6) ones.

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-06 13:58:01 -05:00
Pavel Emelyanov f13c95f0e2 inet_diag: Switch from _GETSOCK to IPPROTO_ numbers
Sorry, but the vger didn't let this message go to the list. Re-sending it with
less spam-filter-prone subject.

When dumping the AF_INET/AF_INET6 sockets user will also specify the protocol,
so prepare the protocol diag handlers to work with IPPROTO_ constants.

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-06 13:58:01 -05:00
Pavel Emelyanov 37f352b5e3 inet_diag: Move byte-code finding up the call-stack
Current code calculates it at fixed offset. This offset will change, so
move the BC calculation upper to make the further patching simpler.

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-06 13:58:01 -05:00
Pavel Emelyanov 8d34172dfd sock_diag: Introduce new message type
This type will run the family+protocol based socket dumping.
Also prepare the stub function for it.

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-06 13:58:01 -05:00
Pavel Emelyanov 7f1fb60c4f inet_diag: Partly rename inet_ to sock_
The ultimate goal is to get the sock_diag module, that works in
family+protocol terms. Currently this is suitable to do on the
inet_diag basis, so rename parts of the code. It will be moved
to sock_diag.c later.

Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-12-06 13:57:36 -05:00
David S. Miller 6dec4ac4ee Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	net/ipv4/inet_diag.c
2011-11-26 14:47:03 -05:00
Alexey Dobriyan 4e3fd7a06d net: remove ipv6_addr_copy()
C assignment can handle struct in6_addr copying.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-22 16:43:32 -05:00
Maciej Żenczykowski 717b6d8366 net-netlink: fix diag to export IPv4 tos for dual-stack IPv6 sockets
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-22 16:03:10 -05:00
Maciej Żenczykowski 06236ac372 net-netlink: Add a new attribute to expose TCLASS values via netlink
commit 3ceca74966 added a TOS attribute.

Unfortunately TOS and TCLASS are both present in a dual-stack v6 socket,
furthermore they can have different values.  As such one cannot in a
sane way expose both through a single attribute.

Signed-off-by: Maciej Żenczyowski <maze@google.com>
CC: Murali Raja <muralira@google.com>
CC: Stephen Hemminger <shemminger@vyatta.com>
CC: Eric Dumazet <eric.dumazet@gmail.com>
CC: David S. Miller <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-11-14 01:08:49 -05:00
Murali Raja 3ceca74966 net-netlink: Add a new attribute to expose TOS values via netlink
This patch exposes the tos value for the TCP sockets when the TOS flag
is requested in the ext_flags for the inet_diag request. This would mainly be
used to expose TOS values for both for TCP and UDP sockets. Currently it is
supported for TCP. When netlink support for UDP would be added the support
to expose the TOS values would alse be done. For IPV4 tos value is exposed
and for IPV6 tclass value is exposed.

Signed-off-by: Murali Raja <muralira@google.com>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-10-12 19:09:18 -04:00
David S. Miller 9f6ec8d697 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
	drivers/net/wireless/iwlwifi/iwl-agn-rxon.c
	drivers/net/wireless/rtlwifi/pci.c
	net/netfilter/ipvs/ip_vs_core.c
2011-06-20 22:29:08 -07:00
Eric Dumazet eeb1497277 inet_diag: fix inet_diag_bc_audit()
A malicious user or buggy application can inject code and trigger an
infinite loop in inet_diag_bc_audit()

Also make sure each instruction is aligned on 4 bytes boundary, to avoid
unaligned accesses.

Reported-by: Dan Rosenberg <drosenberg@vsecurity.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-06-17 16:25:39 -04:00
Greg Rose c7ac8679be rtnetlink: Compute and store minimum ifinfo dump size
The message size allocated for rtnl ifinfo dumps was limited to
a single page.  This is not enough for additional interface info
available with devices that support SR-IOV and caused a bug in
which VF info would not be displayed if more than approximately
40 VFs were created per interface.

Implement a new function pointer for the rtnl_register service that will
calculate the amount of data required for the ifinfo dump and allocate
enough data to satisfy the request.

Signed-off-by: Greg Rose <gregory.v.rose@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2011-06-09 20:38:07 -07:00
Eric Dumazet b71d1d426d inet: constify ip headers and in6_addr
Add const qualifiers to structs iphdr, ipv6hdr and in6_addr pointers
where possible, to make code intention more obvious.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-04-22 11:04:14 -07:00
David S. Miller b8f3ab4290 Revert "netlink: test for all flags of the NLM_F_DUMP composite"
This reverts commit 0ab03c2b14.

It breaks several things including the avahi daemon.

Signed-off-by: David S. Miller <davem@davemloft.net>
2011-01-19 13:34:20 -08:00
Jan Engelhardt 0ab03c2b14 netlink: test for all flags of the NLM_F_DUMP composite
Due to NLM_F_DUMP is composed of two bits, NLM_F_ROOT | NLM_F_MATCH,
when doing "if (x & NLM_F_DUMP)", it tests for _either_ of the bits
being set. Because NLM_F_MATCH's value overlaps with NLM_F_EXCL,
non-dump requests with NLM_F_EXCL set are mistaken as dump requests.

Substitute the condition to test for _all_ bits being set.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-01-09 16:25:03 -08:00
Nelson Elhage 22e76c849d inet_diag: Make sure we actually run the same bytecode we audited.
We were using nlmsg_find_attr() to look up the bytecode by attribute when
auditing, but then just using the first attribute when actually running
bytecode. So, if we received a message with two attribute elements, where only
the second had type INET_DIAG_REQ_BYTECODE, we would validate and run different
bytecode strings.

Fix this by consistently using nlmsg_find_attr everywhere.

Signed-off-by: Nelson Elhage <nelhage@ksplice.com>
Signed-off-by: Thomas Graf <tgraf@infradead.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-11-04 12:26:34 -07:00
Eric Dumazet a02cec2155 net: return operator cleanup
Change "return (EXPR);" to "return EXPR;"

return is not a function, parentheses are not required.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-23 14:33:39 -07:00
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking 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>
2010-03-30 22:02:32 +09:00
Roel Kluin b4ced2b768 netlink: With opcode INET_DIAG_BC_S_LE dport was compared in inet_diag_bc_run()
The s-port should be compared.

Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-01-19 14:12:20 -08:00
Eric Dumazet c720c7e838 inet: rename some inet_sock fields
In order to have better cache layouts of struct sock (separate zones
for rx/tx paths), we need this preliminary patch.

Goal is to transfert fields used at lookup time in the first
read-mostly cache line (inside struct sock_common) and move sk_refcnt
to a separate cache line (only written by rx path)

This patch adds inet_ prefix to daddr, rcv_saddr, dport, num, saddr,
sport and id fields. This allows a future patch to define these
fields as macros, like sk_refcnt, without name clashes.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-10-18 18:52:53 -07:00
Eric Dumazet f373b53b5f tcp: replace ehash_size by ehash_mask
Storing the mask (size - 1) instead of the size allows fast path to be
a bit faster.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-10-13 03:44:02 -07:00
Eric Dumazet 31e6d363ab net: correct off-by-one write allocations reports
commit 2b85a34e91
(net: No more expensive sock_hold()/sock_put() on each tx)
changed initial sk_wmem_alloc value.

We need to take into account this offset when reporting
sk_wmem_alloc to user, in PROC_FS files or various
ioctls (SIOCOUTQ/TIOCOUTQ)

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-06-18 00:29:12 -07:00
Arnaldo Carvalho de Melo ac5978e7f8 inet_diag: Remove dup assignments
These are later assigned to other values without being used meanwhile.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-28 08:03:26 -07:00
Eric Dumazet c25eb3bfb9 net: Convert TCP/DCCP listening hash tables to use RCU
This is the last step to be able to perform full RCU lookups
in __inet_lookup() : After established/timewait tables, we
add RCU lookups to listening hash table.

The only trick here is that a socket of a given type (TCP ipv4,
TCP ipv6, ...) can now flight between two different tables
(established and listening) during a RCU grace period, so we
must use different 'nulls' end-of-chain values for two tables.

We define a large value :

#define LISTENING_NULLS_BASE (1U << 29)

So that slots in listening table are guaranteed to have different
end-of-chain values than slots in established table. A reader can
still detect it finished its lookup in the right chain.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-23 17:22:55 -08:00
David S. Miller 7e3aab4a9c inet_diag: Missed conversion after changing inet ehash lockl to spinlocks.
They are no longer a rwlocks.

Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-21 16:39:19 -08:00
Eric Dumazet 5caea4ea70 net: listening_hash get a spinlock per bucket
This patch prepares RCU migration of listening_hash table for
TCP/DCCP protocols.

listening_hash table being small (32 slots per protocol), we add
a spinlock for each slot, instead of a single rwlock for whole table.

This should reduce hold time of readers, and writers concurrency.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-20 00:40:07 -08:00
Eric Dumazet 3ab5aee7fe net: Convert TCP & DCCP hash tables to use RCU / hlist_nulls
RCU was added to UDP lookups, using a fast infrastructure :
- sockets kmem_cache use SLAB_DESTROY_BY_RCU and dont pay the
  price of call_rcu() at freeing time.
- hlist_nulls permits to use few memory barriers.

This patch uses same infrastructure for TCP/DCCP established
and timewait sockets.

Thanks to SLAB_DESTROY_BY_RCU, no slowdown for applications
using short lived TCP connections. A followup patch, converting
rwlocks to spinlocks will even speedup this case.

__inet_lookup_established() is pretty fast now we dont have to
dirty a contended cache line (read_lock/read_unlock)

Only established and timewait hashtable are converted to RCU
(bind table and listen table are still using traditional locking)

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-11-16 19:40:17 -08:00
Johannes Berg 95a5afca4a net: Remove CONFIG_KMOD from net/ (towards removing CONFIG_KMOD entirely)
Some code here depends on CONFIG_KMOD to not try to load
protocol modules or similar, replace by CONFIG_MODULES
where more than just request_module depends on CONFIG_KMOD
and and also use try_then_request_module in ebtables.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-10-16 15:24:51 -07:00
Andi Kleen 6be547a61d inet_diag: Add empty bucket optimization to inet_diag too
Skip quickly over empty buckets in inet_diag.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-08-28 01:09:54 -07:00
Adrian Bunk 0b04082995 net: remove CVS keywords
This patch removes CVS keywords that weren't updated for a long time
from comments.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-06-11 21:00:38 -07:00
Pavel Emelyanov d86e0dac2c [NETNS]: Tcp-v6 sockets per-net lookup.
Add a net argument to inet6_lookup and propagate it further.
Actually, this is tcp-v6 implementation of what was done for
tcp-v4 sockets in a previous patch.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-31 19:28:20 -08:00
Pavel Emelyanov c67499c0e7 [NETNS]: Tcp-v4 sockets per-net lookup.
Add a net argument to inet_lookup and propagate it further
into lookup calls. Plus tune the __inet_check_established.

The dccp and inet_diag, which use that lookup functions
pass the init_net into them.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-31 19:28:19 -08:00
Arnaldo Carvalho de Melo 8cf8e5a67f [INET_DIAG]: Fix inet_diag_lock_handler error path.
Fixes: http://bugzilla.kernel.org/show_bug.cgi?id=9825

The inet_diag_lock_handler function uses ERR_PTR to encode errors but
its callers were testing against NULL.

This only happens when the only inet_diag modular user, DCCP, is not
built into the kernel or available as a module.

Also there was a problem with not dropping the mutex lock when a handler
was not found, also fixed in this patch.

This caused an OOPS and ss would then hang on subsequent calls, as
&inet_diag_table_mutex was being left locked.

Thanks to spike at ml.yaroslavl.ru for report it after trying 'ss -d'
on a kernel that doesn't have DCCP available.

This bug was introduced in cset
d523a328fb ("Fix inet_diag dead-lock
regression"), after 2.6.24-rc3, so just 2.6.24 seems to be affected.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-31 19:27:08 -08:00
Denis V. Lunev b7c6ba6eb1 [NETNS]: Consolidate kernel netlink socket destruction.
Create a specific helper for netlink kernel socket disposal. This just
let the code look better and provides a ground for proper disposal
inside a namespace.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Tested-by: Alexey Dobriyan <adobriyan@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-01-28 15:08:07 -08:00
Herbert Xu d523a328fb [INET]: Fix inet_diag dead-lock regression
The inet_diag register fix broke inet_diag module loading because the
loaded module had to take the same mutex that's already held by the
loader in order to register the new handler.

This patch fixes it by introducing a separate mutex to protect the
handling of handlers.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2007-12-03 15:51:25 +11:00
Pavel Emelyanov 076931989f [INET]: Fix inet_diag register vs rcv race
The following race is possible when one cpu unregisters the handler
while other one is trying to receive a message and call this one:

CPU1:                                                 CPU2:
inet_diag_rcv()                                       inet_diag_unregister()
  mutex_lock(&inet_diag_mutex);
  netlink_rcv_skb(skb, &inet_diag_rcv_msg);
    if (inet_diag_table[nlh->nlmsg_type] == 
                               NULL) /* false handler is still registered */
    ...
    netlink_dump_start(idiagnl, skb, nlh,
                           inet_diag_dump, NULL);
           cb = kzalloc(sizeof(*cb), GFP_KERNEL);
                   /* sleep here freeing memory 
                    * or preempt
                    * or sleep later on nlk->cb_mutex
                    */
                                                         spin_lock(&inet_diag_register_lock);
                                                         inet_diag_table[type] = NULL;
    ...                                                  spin_unlock(&inet_diag_register_lock);
                                                         synchronize_rcu();
                                                         /* CPU1 is sleeping - RCU quiescent
                                                          * state is passed
                                                          */
                                                         return;
    /* inet_diag_dump is finally called: */
    inet_diag_dump()
      handler = inet_diag_table[cb->nlh->nlmsg_type];
      BUG_ON(handler == NULL); 
      /* OOPS! While we slept the unregister has set
       * handler to NULL :(
       */

Grep showed, that the register/unregister functions are called
from init/fini module callbacks for tcp_/dccp_diag, so it's OK
to use the inet_diag_mutex to synchronize manipulations with the
inet_diag_table and the access to it.

Besides, as Herbert pointed out, asynchronous dumps should hold 
this mutex as well, and thus, we provide the mutex as cb_mutex one.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2007-11-30 00:08:14 +11:00
Eric Dumazet 230140cffa [INET]: Remove per bucket rwlock in tcp/dccp ehash table.
As done two years ago on IP route cache table (commit
22c047ccbc) , we can avoid using one
lock per hash bucket for the huge TCP/DCCP hash tables.

On a typical x86_64 platform, this saves about 2MB or 4MB of ram, for
litle performance differences. (we hit a different cache line for the
rwlock, but then the bucket cache line have a better sharing factor
among cpus, since we dirty it less often). For netstat or ss commands
that want a full scan of hash table, we perform fewer memory accesses.

Using a 'small' table of hashed rwlocks should be more than enough to
provide correct SMP concurrency between different buckets, without
using too much memory. Sizing of this table depends on
num_possible_cpus() and various CONFIG settings.

This patch provides some locking abstraction that may ease a future
work using a different model for TCP/DCCP table.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-11-07 04:15:11 -08:00
Jean Delvare 305e1e9691 [INET]: Let inet_diag and friends autoload
By adding module aliases to inet_diag, tcp_diag and dccp_diag, we let
them load automatically as needed. This makes tools like "ss" run
faster.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-22 02:59:54 -07:00