kernel.git/net/sctp/protocol.c, branch linux-3.12.y

sctp: Fix port hash table size computation

2016-03-02T15:29:15Z

[ Upstream commit d9749fb5942f51555dc9ce1ac0dbb1806960a975 ] Dmitry Vyukov noted recently that the sctp_port_hashtable had an error in its size computation, observing that the current method never guaranteed that the hashsize (measured in number of entries) would be a power of two, which the input hash function for that table requires. The root cause of the problem is that two values need to be computed (one, the allocation order of the storage requries, as passed to __get_free_pages, and two the number of entries for the hash table). Both need to be ^2, but for different reasons, and the existing code is simply computing one order value, and using it as the basis for both, which is wrong (i.e. it assumes that ((1< Reported-by: Dmitry Vyukov CC: Dmitry Vyukov CC: Vladislav Yasevich CC: "David S. Miller" Signed-off-by: David S. Miller Signed-off-by: Jiri Slaby

sctp: fix race on protocol/netns initialization

2015-09-30T11:47:40Z

[ Upstream commit 8e2d61e0aed2b7c4ecb35844fe07e0b2b762dee4 ] Consider sctp module is unloaded and is being requested because an user is creating a sctp socket. During initialization, sctp will add the new protocol type and then initialize pernet subsys: status = sctp_v4_protosw_init(); if (status) goto err_protosw_init; status = sctp_v6_protosw_init(); if (status) goto err_v6_protosw_init; status = register_pernet_subsys(&sctp_net_ops); The problem is that after those calls to sctp_v{4,6}_protosw_init(), it is possible for userspace to create SCTP sockets like if the module is already fully loaded. If that happens, one of the possible effects is that we will have readers for net->sctp.local_addr_list list earlier than expected and sctp_net_init() does not take precautions while dealing with that list, leading to a potential panic but not limited to that, as sctp_sock_init() will copy a bunch of blank/partially initialized values from net->sctp. The race happens like this: CPU 0 | CPU 1 socket() | __sock_create | socket() inet_create | __sock_create list_for_each_entry_rcu( | answer, &inetsw[sock->type], | list) { | inet_create /* no hits */ | if (unlikely(err)) { | ... | request_module() | /* socket creation is blocked | * the module is fully loaded | */ | sctp_init | sctp_v4_protosw_init | inet_register_protosw | list_add_rcu(&p->list, | last_perm); | | list_for_each_entry_rcu( | answer, &inetsw[sock->type], sctp_v6_protosw_init | list) { | /* hit, so assumes protocol | * is already loaded | */ | /* socket creation continues | * before netns is initialized | */ register_pernet_subsys | Simply inverting the initialization order between register_pernet_subsys() and sctp_v4_protosw_init() is not possible because register_pernet_subsys() will create a control sctp socket, so the protocol must be already visible by then. Deferring the socket creation to a work-queue is not good specially because we loose the ability to handle its errors. So, as suggested by Vlad, the fix is to split netns initialization in two moments: defaults and control socket, so that the defaults are already loaded by when we register the protocol, while control socket initialization is kept at the same moment it is today. Fixes: 4db67e808640 ("sctp: Make the address lists per network namespace") Signed-off-by: Vlad Yasevich Signed-off-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller Signed-off-by: Jiri Slaby

sctp: reset flowi4_oif parameter on route lookup

2014-05-29T09:49:20Z

[ Upstream commit 85350871317a5adb35519d9dc6fc9e80809d42ad ] commit 813b3b5db83 (ipv4: Use caller's on-stack flowi as-is in output route lookups.) introduces another regression which is very similar to the problem of commit e6b45241c (ipv4: reset flowi parameters on route connect) wants to fix: Before we call ip_route_output_key() in sctp_v4_get_dst() to get a dst that matches a bind address as the source address, we have already called this function previously and the flowi parameters have been initialized including flowi4_oif, so when we call this function again, the process in __ip_route_output_key() will be different because of the setting of flowi4_oif, and we'll get a networking device which corresponds to the inputted flowi4_oif as the output device, this is wrong because we'll never hit this place if the previously returned source address of dst match one of the bound addresses. To reproduce this problem, a vlan setting is enough: # ifconfig eth0 up # route del default # vconfig add eth0 2 # vconfig add eth0 3 # ifconfig eth0.2 10.0.1.14 netmask 255.255.255.0 # route add default gw 10.0.1.254 dev eth0.2 # ifconfig eth0.3 10.0.0.14 netmask 255.255.255.0 # ip rule add from 10.0.0.14 table 4 # ip route add table 4 default via 10.0.0.254 src 10.0.0.14 dev eth0.3 # sctp_darn -H 10.0.0.14 -P 36422 -h 10.1.4.134 -p 36422 -s -I You'll detect that all the flow are routed to eth0.2(10.0.1.254). Signed-off-by: Xufeng Zhang Signed-off-by: Julian Anastasov Acked-by: Vlad Yasevich Signed-off-by: David S. Miller Signed-off-by: Jiri Slaby

Revert "net: sctp: convert sctp_checksum_disable module param into sctp sysctl"

2013-08-09T20:09:41Z

This reverts commit cda5f98e36576596b9230483ec52bff3cc97eb21. As per Vlad's request. Signed-off-by: David S. Miller

net: sctp: trivial: update bug report in header comment

2013-08-09T18:33:02Z

With the restructuring of the lksctp.org site, we only allow bug reports through the SCTP mailing list linux-sctp@vger.kernel.org, not via SF, as SF is only used for web hosting and nothing more. While at it, also remove the obvious statement that bugs will be fixed and incooperated into the kernel. Signed-off-by: Daniel Borkmann Acked-by: Vlad Yasevich Signed-off-by: David S. Miller

net: sctp: convert sctp_checksum_disable module param into sctp sysctl

2013-08-09T18:33:02Z

Get rid of the last module parameter for SCTP and make this configurable via sysctl for SCTP like all the rest of SCTP's configuration knobs. Signed-off-by: Daniel Borkmann Signed-off-by: David S. Miller

net: sctp: trivial: update mailing list address

2013-07-25T00:53:38Z

The SCTP mailing list address to send patches or questions to is linux-sctp@vger.kernel.org and not lksctp-developers@lists.sourceforge.net anymore. Therefore, update all occurences. Signed-off-by: Daniel Borkmann Acked-by: Neil Horman Acked-by: Vlad Yasevich Signed-off-by: David S. Miller

net: sctp: rework debugging framework to use pr_debug and friends

2013-07-02T06:22:13Z

We should get rid of all own SCTP debug printk macros and use the ones that the kernel offers anyway instead. This makes the code more readable and conform to the kernel code, and offers all the features of dynamic debbuging that pr_debug() et al has, such as only turning on/off portions of debug messages at runtime through debugfs. The runtime cost of having CONFIG_DYNAMIC_DEBUG enabled, but none of the debug statements printing, is negligible [1]. If kernel debugging is completly turned off, then these statements will also compile into "empty" functions. While we're at it, we also need to change the Kconfig option as it /now/ only refers to the ifdef'ed code portions in outqueue.c that enable further debugging/tracing of SCTP transaction fields. Also, since SCTP_ASSERT code was enabled with this Kconfig option and has now been removed, we transform those code parts into WARNs resp. where appropriate BUG_ONs so that those bugs can be more easily detected as probably not many people have SCTP debugging permanently turned on. To turn on all SCTP debugging, the following steps are needed: # mount -t debugfs none /sys/kernel/debug # echo -n 'module sctp +p' > /sys/kernel/debug/dynamic_debug/control This can be done more fine-grained on a per file, per line basis and others as described in [2]. [1] https://www.kernel.org/doc/ols/2009/ols2009-pages-39-46.pdf [2] Documentation/dynamic-debug-howto.txt Signed-off-by: Daniel Borkmann Signed-off-by: David S. Miller

sctp: Convert __list_for_each use to list_for_each

2013-06-20T06:02:49Z

Signed-off-by: Dave Jones Signed-off-by: David S. Miller

net: sctp: remove SCTP_STATIC macro

2013-06-18T00:08:05Z

SCTP_STATIC is just another define for the static keyword. It's use is inconsistent in the SCTP code anyway and it was introduced in the initial implementation of SCTP in 2.5. We have a regression suite in lksctp-tools, but this is for user space only, so noone makes use of this macro anymore. The kernel test suite for 2.5 is incompatible with the current SCTP code anyway. So simply Remove it, to be more consistent with the rest of the kernel code. Signed-off-by: Daniel Borkmann Acked-by: Vlad Yasevich Signed-off-by: David S. Miller