ICMP protocol unreachable handling completely disregarded
the fact that the user may have locked the socket. It proceeded
to destroy the association, even though the user may have
held the lock and had a ref on the association. This resulted
in the following:
Attempt to release alive inet socket f6afcc00
=========================
[ BUG: held lock freed! ]
-------------------------
somenu/2672 is freeing memory f6afcc00-f6afcfff, with a lock still held
there!
(sk_lock-AF_INET){+.+.+.}, at: [<c122098a>] sctp_connect+0x13/0x4c
1 lock held by somenu/2672:
#0: (sk_lock-AF_INET){+.+.+.}, at: [<c122098a>] sctp_connect+0x13/0x4c
stack backtrace:
Pid: 2672, comm: somenu Not tainted 2.6.32-telco #55
Call Trace:
[<c1232266>] ? printk+0xf/0x11
[<c1038553>] debug_check_no_locks_freed+0xce/0xff
[<c10620b4>] kmem_cache_free+0x21/0x66
[<c1185f25>] __sk_free+0x9d/0xab
[<c1185f9c>] sk_free+0x1c/0x1e
[<c1216e38>] sctp_association_put+0x32/0x89
[<c1220865>] __sctp_connect+0x36d/0x3f4
[<c122098a>] ? sctp_connect+0x13/0x4c
[<c102d073>] ? autoremove_wake_function+0x0/0x33
[<c12209a8>] sctp_connect+0x31/0x4c
[<c11d1e80>] inet_dgram_connect+0x4b/0x55
[<c11834fa>] sys_connect+0x54/0x71
[<c103a3a2>] ? lock_release_non_nested+0x88/0x239
[<c1054026>] ? might_fault+0x42/0x7c
[<c1054026>] ? might_fault+0x42/0x7c
[<c11847ab>] sys_socketcall+0x6d/0x178
[<c10da994>] ? trace_hardirqs_on_thunk+0xc/0x10
[<c1002959>] syscall_call+0x7/0xb
This was because the sctp_wait_for_connect() would aqcure the socket
lock and then proceed to release the last reference count on the
association, thus cause the fully destruction path to finish freeing
the socket.
The simplest solution is to start a very short timer in case the socket
is owned by user. When the timer expires, we can do some verification
and be able to do the release properly.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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>
sk_add_backlog -> __sk_add_backlog
sk_add_backlog_limited -> sk_add_backlog
Signed-off-by: Zhu Yi <yi.zhu@intel.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Make sctp adapt to the limited socket backlog change.
Cc: Vlad Yasevich <vladislav.yasevich@hp.com>
Cc: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: Zhu Yi <yi.zhu@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The sctp crc32c checksum is always generated in little endian.
So, we clean up the code to treat it as little endian and remove
all the __force casts.
Suggested by Herbert Xu.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is a new version of my patch, now using a module parameter instead
of a sysctl, so that the option is harder to find. Please note that,
once the module is loaded, it is still possible to change the value of
the parameter in /sys/module/sctp/parameters/, which is useful if you
want to do performance comparisons without rebooting.
Computation of SCTP checksums significantly affects the performance of
SCTP. For example, using two dual-Opteron 246 connected using a Gbe
network, it was not possible to achieve more than ~730 Mbps, compared to
941 Mbps after disabling SCTP checksums.
Unfortunately, SCTP checksum offloading in NICs is not commonly
available (yet).
By default, checksums are still enabled, of course.
Signed-off-by: Lucas Nussbaum <lucas.nussbaum@ens-lyon.fr>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There is a race between sctp_rcv() and sctp_accept() where we
have moved the association from the listening socket to the
accepted socket, but sctp_rcv() processing cached the old
socket and continues to use it.
The easy solution is to check for the socket mismatch once we've
grabed the socket lock. If we hit a mis-match, that means
that were are currently holding the lock on the listening socket,
but the association is refrencing a newly accepted socket. We need
to drop the lock on the old socket and grab the lock on the new one.
A more proper solution might be to create accepted sockets when
the new association is established, similar to TCP. That would
eliminate the race for 1-to-1 style sockets, but it would still
existing for 1-to-many sockets where a user wished to peeloff an
association. For now, we'll live with this easy solution as
it addresses the problem.
Reported-by: Michal Hocko <mhocko@suse.cz>
Reported-by: Karsten Keil <kkeil@suse.de>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If ICMP packet too big message is received with MTU larger than current
PMTU, SCTP will still accept this ICMP message and sync the PMTU of assoc
with the wrong MTU.
Endpoing A Endpoint B
(ESTABLISHED) (ESTABLISHED)
ICMP --------->
(packet too big, MTU too larger)
sync PMTU
This patch fixed the problem by drop that ICMP message.
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch add to validate initiate tag and chunk type if verification
tag is 0 when handling ICMP message.
RFC 4960, Appendix C. ICMP Handling
ICMP6) An implementation MUST validate that the Verification Tag
contained in the ICMP message matches the Verification Tag of the peer.
If the Verification Tag is not 0 and does NOT match, discard the ICMP
message. If it is 0 and the ICMP message contains enough bytes to
verify that the chunk type is an INIT chunk and that the Initiate Tag
matches the tag of the peer, continue with ICMP7. If the ICMP message
is too short or the chunk type or the Initiate Tag does not match,
silently discard the packet.
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
__FUNCTION__ is gcc-specific, use __func__
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
I was notified by Randy Stewart that lksctp claims to be
"the reference implementation". First of all, "the
refrence implementation" was the original implementation
of SCTP in usersapce written ty Randy and a few others.
Second, after looking at the definiton of 'reference implementation',
we don't really meet the requirements.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
ADD-IP draft section 5.2 specifies that if an association can not
be found using the source and destination of the IP packet,
then, if the packet contains ASCONF chunks, the Address Parameter
TLV should be used to lookup an association.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The crc32c library used an identical table and algorithm
as SCTP. Switch to using the library instead of carrying
our own table. Using crypto layer proved to have too
much overhead compared to using the library directly.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch implements the receive path needed to process authenticated
chunks. Add ability to process the AUTH chunk and handle edge cases
for authenticated COOKIE-ECHO as well.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
RFC 4460 and future RFC 4960 (2960-bis) specify that packets
with bundled INIT chunks need to be dropped. We currenlty do
that only after processing any leading chunks. For OOTB chunks,
since we already walk the entire packet, we should discard packets
with bundled INITs.
There are other chunks chunks that MUST NOT be bundled, but the spec
is silent on theire treatment. Thus, we'll leave their teatment
alone for the moment.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Acked-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Forward declarion is static, the function itself is not. Make it
consistent.
Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Currently, if the socket is owned by the user, we drop the ICMP
message. As a result SCTP forgets that path MTU changed and
never adjusting it's estimate. This causes all subsequent
packets to be fragmented. With this patch, we'll flag the association
that it needs to udpate it's estimate based on the already updated
routing information.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Acked-by: Sridhar Samudrala <sri@us.ibm.com>
Introduce new function sctp_transport_update_pmtu that updates
the transports and destination caches view of the path mtu.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Acked-by: Sridhar Samudrala <sri@us.ibm.com>
When a transmitted packet is looped back directly, CHECKSUM_PARTIAL
maps to the semantics of CHECKSUM_UNNECESSARY. Therefore we should
treat it as such in the stack.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
So that it is also an offset from skb->head, reduces its size from 8 to 4 bytes
on 64bit architectures, allowing us to combine the 4 bytes hole left by the
layer headers conversion, reducing struct sk_buff size to 256 bytes, i.e. 4
64byte cachelines, and since the sk_buff slab cache is SLAB_HWCACHE_ALIGN...
:-)
Many calculations that previously required that skb->{transport,network,
mac}_header be first converted to a pointer now can be done directly, being
meaningful as offsets or pointers.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Renaming skb->h to skb->transport_header, skb->nh to skb->network_header and
skb->mac to skb->mac_header, to match the names of the associated helpers
(skb[_[re]set]_{transport,network,mac}_header).
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
For consistency with all the other skb->h.raw accessors.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
For the quite common 'skb->h.raw - skb->data' sequence.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This time of the type:
skb->nh.iph = (struct iphdr *)skb->data;
That is completely equivalent to:
skb->nh.raw = skb->data;
Wonder why people love casts... :-)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Ditto for its only caller (sctp_endpoint_is_peeled_off)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Along with it, statics in input.c that end up calling it
(__sctp_lookup_association, sctp_lookup_association,
__sctp_rcv_init_lookup, __sctp_rcv_lookup). Callers
are adjusted.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
The only caller (__sctp_rcv_lookup_endpoint()) also switched,
its caller adjusted
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Every time SCTP creates a temporary association, the stack hashes it,
puts it on a list of endpoint associations and increments the backlog.
However, the lifetime of a temporary association is the processing time
of a current packet and it's destroyed after that. In fact, we don't
really want anyone else finding this association. There is no reason to
do this extra work.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
I was looking at a RHEL5 bug report involving Xen and SCTP
(https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=212550).
It turns out that SCTP wasn't written to handle skb fragments at
all. The absence of any calls to skb_may_pull is testament to
that.
It just so happens that Xen creates fragmented packets more often
than other scenarios (header & data split when going from domU to
dom0). That's what caused this bug to show up.
Until someone has the time sits down and audits the entire net/sctp
directory, here is a conservative and safe solution that simply
linearises all packets on input.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
We only need the timestamp on COOKIE-ECHO chunks, so instead of always
timestamping every SCTP packet, let common code timestamp if the socket
option is set. For COOKIE-ECHO, simply get the time of day if we don't
have a timestamp. This introduces a small possibility that the cookie
may be considered expired, but it will be renegotiated.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Function sk_filter() is called from tcp_v{4,6}_rcv() functions with arg
needlock = 0, while socket is not locked at that moment. In order to avoid
this and similar issues in the future, use rcu for sk->sk_filter field read
protection.
Signed-off-by: Dmitry Mishin <dim@openvz.org>
Signed-off-by: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Signed-off-by: Kirill Korotaev <dev@openvz.org>
This patch adds more statistics info under /proc/net/sctp/snmp
that should be useful for debugging. The additional events that
are counted now include timer expirations, retransmits, packet
and data chunk discards.
The Data chunk discards include all the cases where a data chunk
is discarded including high tsn, bad stream, dup tsn and the most
useful one(out of receive buffer/rwnd).
Also moved the SCTP MIB data structures from the generic include
directories to include/sctp/sctp.h.
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
