We got system OOM while running some UDP netperf testing on the loopback
device. The case is multiple senders sent stream UDP packets to a single
receiver via loopback on local host. Of course, the receiver is not able
to handle all the packets in time. But we surprisingly found that these
packets were not discarded due to the receiver's sk->sk_rcvbuf limit.
Instead, they are kept queuing to sk->sk_backlog and finally ate up all
the memory. We believe this is a secure hole that a none privileged user
can crash the system.
The root cause for this problem is, when the receiver is doing
__release_sock() (i.e. after userspace recv, kernel udp_recvmsg ->
skb_free_datagram_locked -> release_sock), it moves skbs from backlog to
sk_receive_queue with the softirq enabled. In the above case, multiple
busy senders will almost make it an endless loop. The skbs in the
backlog end up eat all the system memory.
The issue is not only for UDP. Any protocols using socket backlog is
potentially affected. The patch adds limit for socket backlog so that
the backlog size cannot be expanded endlessly.
Reported-by: Alex Shi <alex.shi@intel.com>
Cc: David Miller <davem@davemloft.net>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru
Cc: "Pekka Savola (ipv6)" <pekkas@netcore.fi>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Vlad Yasevich <vladislav.yasevich@hp.com>
Cc: Sridhar Samudrala <sri@us.ibm.com>
Cc: Jon Maloy <jon.maloy@ericsson.com>
Cc: Allan Stephens <allan.stephens@windriver.com>
Cc: Andrew Hendry <andrew.hendry@gmail.com>
Signed-off-by: Zhu Yi <yi.zhu@intel.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix TIPC to disallow sending to remote addresses prior to entering NET_MODE
user programs can oops the kernel by sending datagrams via AF_TIPC prior to
entering networked mode. The following backtrace has been observed:
ID: 13459 TASK: ffff810014640040 CPU: 0 COMMAND: "tipc-client"
[exception RIP: tipc_node_select_next_hop+90]
RIP: ffffffff8869d3c3 RSP: ffff81002d9a5ab8 RFLAGS: 00010202
RAX: 0000000000000001 RBX: 0000000000000001 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000001001001
RBP: 0000000001001001 R8: 0074736575716552 R9: 0000000000000000
R10: ffff81003fbd0680 R11: 00000000000000c8 R12: 0000000000000008
R13: 0000000000000001 R14: 0000000000000001 R15: ffff810015c6ca00
ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018
RIP: 0000003cbd8d49a3 RSP: 00007fffc84e0be8 RFLAGS: 00010206
RAX: 000000000000002c RBX: ffffffff8005d116 RCX: 0000000000000000
RDX: 0000000000000008 RSI: 00007fffc84e0c00 RDI: 0000000000000003
RBP: 0000000000000000 R8: 00007fffc84e0c10 R9: 0000000000000010
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fffc84e0d10 R14: 0000000000000000 R15: 00007fffc84e0c30
ORIG_RAX: 000000000000002c CS: 0033 SS: 002b
What happens is that, when the tipc module in inserted it enters a standalone
node mode in which communication to its own address is allowed <0.0.0> but not
to other addresses, since the appropriate data structures have not been
allocated yet (specifically the tipc_net pointer). There is nothing stopping a
client from trying to send such a message however, and if that happens, we
attempt to dereference tipc_net.zones while the pointer is still NULL, and
explode. The fix is pretty straightforward. Since these oopses all arise from
the dereference of global pointers prior to their assignment to allocated
values, and since these allocations are small (about 2k total), lets convert
these pointers to static arrays of the appropriate size. All the accesses to
these bits consider 0/NULL to be a non match when searching, so all the lookups
still work properly, and there is no longer a chance of a bad dererence
anywhere. As a bonus, this lets us eliminate the setup/teardown routines for
those pointers, and elimnates the need to preform any locking around them to
prevent access while their being allocated/freed.
I've updated the tipc_net structure to behave this way to fix the exact reported
problem, and also fixed up the tipc_bearers and media_list arrays to fix an
obvious simmilar problem that arises from issuing tipc-config commands to
manipulate bearers/links prior to entering networked mode
I've tested this for a few hours by running the sanity tests and stress test
with the tipcutils suite, and nothing has fallen over. There have been a few
lockdep warnings, but those were there before, and can be addressed later, as
they didn't actually result in any deadlock.
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: Allan Stephens <allan.stephens@windriver.com>
CC: David S. Miller <davem@davemloft.net>
CC: tipc-discussion@lists.sourceforge.net
bearer.c | 37 ++++++-------------------------------
bearer.h | 2 +-
net.c | 25 ++++---------------------
3 files changed, 11 insertions(+), 53 deletions(-)
Signed-off-by: David S. Miller <davem@davemloft.net>
ipgre_header() can be called with zero daddr when the gre device is
configured as multipoint tunnel and still has the NOARP flag set (which is
typically cleared by the userspace arp daemon). If the NOARP packets are
not dropped, ipgre_tunnel_xmit() will take rt->rt_gateway (= NBMA IP) and
use that for route look up (and may lead to bogus xfrm acquires).
The multicast address check is removed as sending to multicast group should
be ok. In fact, if gre device has a multicast address as destination
ipgre_header is always called with multicast address.
Signed-off-by: Timo Teras <timo.teras@iki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
This solves a potential race problem during the cleanup process.
The issue is that addrconf_ifdown() needs to traverse address list,
but then drop lock to call the notifier. The version in -next
could get confused if add/delete happened during this window.
Original code (2.6.32 and earlier) was okay because all addresses
were always deleted.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
My recent change in net-next to retain permanent addresses caused regression.
Device refcount would not go to zero when device was unregistered because
left over anycast reference would hold ipv6 dev reference which would hold
device references...
The correct procedure is to call notify chain when address is no longer
available for use. When interface comes back DAD timer will notify
back that address is available.
Also, link local addresses should be purged when interface is brought
down. The address might be changed.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The Router Solicitation timer races with device state changes
because it doesn't lock the device. Use local variable to avoid
one repeated dereference.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Timer code runs in bottom half, so there is no need for
using _bh form of locking. Also check if device is not ready
to avoid race with address that is no longer active.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Handling HT configuration changes involved setting the channel
with the new HT parameters and then issuing a rate_update()
notification to the driver.
This behavior changed after the off-channel changes. Now, the channel
is not updated with the new HT params in enable_ht() - instead, it
is now done when the scan work terminates. This results in the driver
depending on stale information, defaulting to non-HT mode always.
Fix this by passing the new channel type to the driver.
Cc: stable@kernel.org
Signed-off-by: Sujith <Sujith.Manoharan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
br_multicast calls ip_send_check(), so it should depend on INET.
built-in:
br_multicast.c:(.text+0x88cf4): undefined reference to `ip_send_check'
or modular:
ERROR: "ip_send_check" [net/bridge/bridge.ko] undefined!
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The inquiry cache information in debugfs should be using seq_file support
and not allocating memory on the stack for the string. Since the usage of
these information is really seldom, using single_open() for it is good
enough.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
My previous patch 914c8ad2d1 incorrectly changed
the length check in packet_mc_add to be more strict. The problem is that
userspace is not filling this field (and it stays zeroed) in case of setting
PACKET_MR_PROMISC or PACKET_MR_ALLMULTI. So move the strict check to the point
in path where the addr_len must be set correctly.
Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Reported-by: Pavel Roskin <proski@gnu.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
When I merged the bundle creation code, I introduced a bogus
flowi value in the bundle. Instead of getting from the caller,
it was instead set to the flow in the route object, which is
totally different.
The end result is that the bundles we created never match, and
we instead end up with an ever growing bundle list.
Thanks to Jamal for find this problem.
Reported-by: Jamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Steffen Klassert <steffen.klassert@secunet.com>
Acked-by: Jamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit e1dd33f60ced091114e4aacf141e0d03b88d3e13 changed cfg80211 to
allow association commands while in associated state to enable support
for roaming within an ESS. However, this was not enough to resolve all
cases with mac80211 which needs some additional handling of the
reassociation case to clear internal state with the BSS that was in use
previously.
This patch makes ieee80211_mgd_assoc() accept a valid reassociation
command and clean the association state with the previous BSS. This
fixes roaming between BSSes in an ESS when using wpa_supplicant with
-Dnl80211.
Signed-off-by: Jouni Malinen <j@w1.fi>
Cc: stable@kernel.org
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Add support for handling KEY_RFKILL in the rfkill input module. This
simply toggles the state of all rfkill devices. The comment in rfkill.h
is also updated to reflect that RFKILL_TYPE_ALL may be used inside the
kernel.
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Fix the following build error when IGMP_SNOOPING is not enabled.
In file included from net/bridge/br.c:24:
net/bridge/br_private.h: In function 'br_multicast_is_router':
net/bridge/br_private.h:361: error: 'struct net_bridge' has no member named 'multicast_router'
net/bridge/br_private.h:362: error: 'struct net_bridge' has no member named 'multicast_router'
net/bridge/br_private.h:363: error: 'struct net_bridge' has no member named 'multicast_router_timer'
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
We use scm_send and scm_recv on both unix domain and
netlink sockets, but only unix domain sockets support
everything required for file descriptor passing,
so error if someone attempts to pass file descriptors
over netlink sockets.
Cc: stable@kernel.org
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (44 commits)
rcu: Fix accelerated GPs for last non-dynticked CPU
rcu: Make non-RCU_PROVE_LOCKING rcu_read_lock_sched_held() understand boot
rcu: Fix accelerated grace periods for last non-dynticked CPU
rcu: Export rcu_scheduler_active
rcu: Make rcu_read_lock_sched_held() take boot time into account
rcu: Make lockdep_rcu_dereference() message less alarmist
sched, cgroups: Fix module export
rcu: Add RCU_CPU_STALL_VERBOSE to dump detailed per-task information
rcu: Fix rcutorture mod_timer argument to delay one jiffy
rcu: Fix deadlock in TREE_PREEMPT_RCU CPU stall detection
rcu: Convert to raw_spinlocks
rcu: Stop overflowing signed integers
rcu: Use canonical URL for Mathieu's dissertation
rcu: Accelerate grace period if last non-dynticked CPU
rcu: Fix citation of Mathieu's dissertation
rcu: Documentation update for CONFIG_PROVE_RCU
security: Apply lockdep-based checking to rcu_dereference() uses
idr: Apply lockdep-based diagnostics to rcu_dereference() uses
radix-tree: Disable RCU lockdep checking in radix tree
vfs: Abstract rcu_dereference_check for files-fdtable use
...
NETIF_F_NTUPLE flag setting introduced a bug: non-ntuple flags
like LRO may be successfully set, before ioctl(2) returns failure
to userspace.
The set-flags operation should be all-or-none, rather than leaving
things in an inconsistent state prior to reporting failure to
userspace.
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The Inode field in /proc/net/{tcp,udp,packet,raw,...} is useful to know the types of
file descriptors associated to a process. Actually lsof utility uses the field.
Unfortunately, unlike /proc/net/{tcp,udp,packet,raw,...}, /proc/net/netlink doesn't have the field.
This patch adds the field to /proc/net/netlink.
Signed-off-by: Masatake YAMATO <yamato@redhat.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Zhu Yi
Neil Horman
Timo Teräs
stephen hemminger
David S. Miller
Sujith
Randy Dunlap
Marcel Holtmann
Jiri Pirko
Herbert Xu
Jouni Malinen
Matthew Garrett
Sridhar Samudrala
Eric W. Biederman
Linus Torvalds
Jeff Garzik
Masatake YAMATO