Unconditional use of skb->dev won't work here,
try to fetch the econet device via skb_dst()->dev
instead.
Suggested by Eric Dumazet.
Reported-by: Nelson Elhage <nelhage@ksplice.com>
Tested-by: Nelson Elhage <nelhage@ksplice.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Make sure sysctl_tcp_cookie_size is read once in
tcp_cookie_size_check(), or we might return an illegal value to caller
if sysctl_tcp_cookie_size is changed by another cpu.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ben Hutchings <bhutchings@solarflare.com>
Cc: William Allen Simpson <william.allen.simpson@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
sysctl_tcp_tso_win_divisor might be set to zero while one cpu runs in
tcp_tso_should_defer(). Make sure we dont allow a divide by zero by
reading sysctl_tcp_tso_win_divisor exactly once.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Rather than printing the message to the log, use a mib counter to keep
track of the count of occurences of time wait bucket overflow. Reduces
spam in logs.
Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
x25 does not decrement the network device reference counts on module unload.
Thus unregistering any pre-existing interface after unloading the x25 module
hangs and results in
unregister_netdevice: waiting for tap0 to become free. Usage count = 1
This patch decrements the reference counts of all interfaces in x25_link_free,
the way it is already done in x25_link_device_down for NETDEV_DOWN events.
Signed-off-by: Apollon Oikonomopoulos <apollon@noc.grnet.gr>
Signed-off-by: David S. Miller <davem@davemloft.net>
Using the SOCK_DGRAM enum results in
"net-pf-2-proto-SOCK_DGRAM-type-115", so use the numeric value like it
is done in net/dccp.
Signed-off-by: Michal Marek <mmarek@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
We need to drop the mutex and do a dev_put, so set an error code and break like
the other paths, instead of returning directly.
Signed-off-by: Nelson Elhage <nelhage@ksplice.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Le dimanche 05 décembre 2010 à 12:23 +0100, Eric Dumazet a écrit :
> Le dimanche 05 décembre 2010 à 09:19 +0100, Eric Dumazet a écrit :
>
> > Hmm..
> >
> > If somebody can explain why RTNL is held in arp_ioctl() (and therefore
> > in arp_req_delete()), we might first remove RTNL use in arp_ioctl() so
> > that your patch can be applied.
> >
> > Right now it is not good, because RTNL wont be necessarly held when you
> > are going to call arp_invalidate() ?
>
> While doing this analysis, I found a refcount bug in llc, I'll send a
> patch for net-2.6
Oh well, of course I must first fix the bug in net-2.6, and wait David
pull the fix in net-next-2.6 before sending this rcu conversion.
Note: this patch should be sent to stable teams (2.6.34 and up)
[PATCH net-2.6] llc: fix a device refcount imbalance
commit abf9d537fe (llc: add support for SO_BINDTODEVICE) added one
refcount imbalance in llc_ui_bind(), because dev_getbyhwaddr() doesnt
take a reference on device, while dev_get_by_index() does.
Fix this using RCU locking. And since an RCU conversion will be done for
2.6.38 for dev_getbyhwaddr(), put the rcu_read_lock/unlock exactly at
their final place.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: stable@kernel.org
Cc: Octavian Purdila <opurdila@ixiacom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The bug has to do with boundary checks on the initial receive window.
If the initial receive window falls between init_cwnd and the
receive window specified by the user, the initial window is incorrectly
brought down to init_cwnd. The correct behavior is to allow it to
remain unchanged.
Signed-off-by: Nandita Dukkipati <nanditad@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pavel Emelyanov tried to fix a race between sk_filter_(de|at)tach and
sk_clone() in commit 47e958eac2
Problem is we can have several clones sharing a common sk_filter, and
these clones might want to sk_filter_attach() their own filters at the
same time, and can overwrite old_filter->rcu, corrupting RCU queues.
We can not use filter->rcu without being sure no other thread could do
the same thing.
Switch code to a more conventional ref-counting technique : Do the
atomic decrement immediately and queue one rcu call back when last
reference is released.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
I found a problem using an IPv6 over IPv4 tunnel. When CONFIG_IPV6_SIT
was enabled, the packets would be rejected as net/ipv6/sit.c was catching
all IPPROTO_IPV6 packets and returning an ICMP port unreachable error.
I think this patch fixes the problem cleanly. I believe the code in
net/ipv4/tunnel4.c:tunnel4_rcv takes care of it properly if none of the
handlers claim the skb.
Signed-off-by: David McCullough <david_mccullough@mcafee.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The ip6_tunnel always assumes it consumes 40 bytes (ip6 hdr) of the mtu of the
underlaying device. So for a normal ethernet bearer, the mtu of the ip6_tunnel is
1460.
However, when creating a tunnel the encap limit option is enabled by default, and it
consumes 8 bytes more, so the true mtu shall be 1452.
I dont really know if this breaks some statement in some RFC, so this is a request for
comments.
Signed-off-by: Anders Franzen <anders.franzen@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Th commit titled "mac80211: clean up rx handling wrt. found_sta"
removed found_sta variable which caused a MIC failure event
to be reported twice for a single failure to supplicant resulted
in STA disconnect.
This should fix WPA specific countermeasures WiFi test case (5.2.17)
issues with mac80211 based drivers which report MIC failure events in
rx status.
Cc: Stable <stable@kernel.org> (2.6.37)
Signed-off-by: Senthil Balasubramanian <senthilkumar@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This patch fixes an curious issue due to insufficient
rx frame filtering.
Saqeb Akhter reported frequent disconnects while streaming
videos over samba: <http://marc.info/?m=128600031109136>
> [ 1166.512087] wlan1: deauthenticated from 30:46:9a:10:49:f7 (Reason: 7)
> [ 1526.059997] wlan1: deauthenticated from 30:46:9a:10:49:f7 (Reason: 7)
> [ 2125.324356] wlan1: deauthenticated from 30:46:9a:10:49:f7 (Reason: 7)
> [...]
The reason is that the device generates frames with slightly
bogus SA/TA addresses.
e.g.:
[ 2314.402316] Ignore 9f:1f:31:f8:64:ff
[ 2314.402321] Ignore 9f:1f:31:f8:64:ff
[ 2352.453804] Ignore 0d:1f:31:f8:64:ff
[ 2352.453808] Ignore 0d:1f:31:f8:64:ff
^^ the group-address flag is set!
(the correct SA/TA would be: 00:1f:31:f8:64:ff)
Since the AP does not know from where the frames come, it
generates a DEAUTH response for the (invalid) mcast address.
This mcast deauth frame then passes through all filters and
tricks the stack into thinking that the AP brutally kicked
us!
This patch fixes the problem by simply ignoring
non-broadcast, group-addressed deauth/disassoc frames.
Cc: Jouni Malinen <j@w1.fi>
Cc: Johannes Berg <johannes@sipsolutions.net>
Reported-by: Saqeb Akhter <saqeb.akhter@gmail.com>
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
In order for frame injection to work properly for some use cases
(e.g., finding the station entry and keys for encryption), mac80211
needs to find the correct sdata entry. This works when the main vif
is in AP mode, but commit a2c1e3dad5
broke this particular use case for station main vif. While this type of
injection is quite unusual operation, it has some uses and we should fix
it. Do this by changing the monitor vif sdata selection to allow station
vif to be selected instead of limiting it to just AP vifs. We still need
to skip some iftypes to avoid selecting unsuitable vif for injection.
Signed-off-by: Jouni Malinen <jouni.malinen@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Its easy to eat all kernel memory and trigger NMI watchdog, using an
exploit program that queues unix sockets on top of others.
lkml ref : http://lkml.org/lkml/2010/11/25/8
This mechanism is used in applications, one choice we have is to have a
recursion limit.
Other limits might be needed as well (if we queue other types of files),
since the passfd mechanism is currently limited by socket receive queue
sizes only.
Add a recursion_level to unix socket, allowing up to 4 levels.
Each time we send an unix socket through sendfd mechanism, we copy its
recursion level (plus one) to receiver. This recursion level is cleared
when socket receive queue is emptied.
Reported-by: Марк Коренберг <socketpair@gmail.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
inet sockets corresponding to passive connections are added to the bind hash
using ___inet_inherit_port(). These sockets are later removed from the bind
hash using __inet_put_port(). These two functions are not exactly symmetrical.
__inet_put_port() decrements hashinfo->bsockets and tb->num_owners, whereas
___inet_inherit_port() does not increment them. This results in both of these
going to -ve values.
This patch fixes this by calling inet_bind_hash() from ___inet_inherit_port(),
which does the right thing.
'bsockets' and 'num_owners' were introduced by commit a9d8f9110d
(inet: Allowing more than 64k connections and heavily optimize bind(0))
Signed-off-by: Nagendra Singh Tomar <tomer_iisc@yahoo.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
A single uninitialized padding byte is leaked to userspace.
Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com>
CC: stable <stable@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This fixes a bug in updating the Greatest Acknowledgment number Received (GAR):
the current implementation does not track the greatest received value -
lower values in the range AWL..AWH (RFC 4340, 7.5.1) erase higher ones.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
tcp_win_from_space() does the following:
if (sysctl_tcp_adv_win_scale <= 0)
return space >> (-sysctl_tcp_adv_win_scale);
else
return space - (space >> sysctl_tcp_adv_win_scale);
"space" is int.
As per C99 6.5.7 (3) shifting int for 32 or more bits is
undefined behaviour.
Indeed, if sysctl_tcp_adv_win_scale is exactly 32,
space >> 32 equals space and function returns 0.
Which means we busyloop in tcp_fixup_rcvbuf().
Restrict net.ipv4.tcp_adv_win_scale to [-31, 31].
Fix https://bugzilla.kernel.org/show_bug.cgi?id=20312
Steps to reproduce:
echo 32 >/proc/sys/net/ipv4/tcp_adv_win_scale
wget www.kernel.org
[softlockup]
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The /proc/net/tcp leaks openreq sockets from other namespaces.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove the if and else conditional because the code is in mainline and there
is no need in it being there.
Signed-off-by: Tracey Dent <tdent48227@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Don't declare variable sized array of iovecs on the stack since this
could cause stack overflow if msg->msgiovlen is large. Instead, coalesce
the user-supplied data into a new buffer and use a single iovec for it.
Signed-off-by: Phil Blundell <philb@gnu.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add missing check for capable(CAP_NET_ADMIN) in SIOCSIFADDR operation.
Signed-off-by: Phil Blundell <philb@gnu.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Later parts of econet_sendmsg() rely on saddr != NULL, so return early
with EINVAL if NULL was passed otherwise an oops may occur.
Signed-off-by: Phil Blundell <philb@gnu.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Vegard Nossum found a unix socket OOM was possible, posting an exploit
program.
My analysis is we can eat all LOWMEM memory before unix_gc() being
called from unix_release_sock(). Moreover, the thread blocked in
unix_gc() can consume huge amount of time to perform cleanup because of
huge working set.
One way to handle this is to have a sensible limit on unix_tot_inflight,
tested from wait_for_unix_gc() and to force a call to unix_gc() if this
limit is hit.
This solves the OOM and also reduce overall latencies, and should not
slowdown normal workloads.
Reported-by: Vegard Nossum <vegard.nossum@gmail.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix ref count bug introduced by
commit 2de7957072
Author: Lorenzo Colitti <lorenzo@google.com>
Date: Wed Oct 27 18:16:49 2010 +0000
ipv6: addrconf: don't remove address state on ifdown if the address
is being kept
Fix logic so that addrconf_ifdown() decrements the inet6_ifaddr
refcnt correctly with in6_ifa_put().
Reported-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We forgot to use __GFP_HIGHMEM in several __vmalloc() calls.
In ceph, add the missing flag.
In fib_trie.c, xfrm_hash.c and request_sock.c, using vzalloc() is
cleaner and allows using HIGHMEM pages as well.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix kernel-doc warning for sk_filter_rcu_release():
Warning(net/core/filter.c:586): missing initial short description on line:
* sk_filter_rcu_release: Release a socket filter by rcu_head
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: netdev@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
When NF_CONNTRACK is enabled, IP_VS uses conntrack symbols.
Therefore IP_VS can't be linked statically when conntrack
is built modular.
Reported-by: Justin P. Mattock <justinmattock@gmail.com>
Tested-by: Justin P. Mattock <justinmattock@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
irttp_data_request() returns meaningful errorcodes, while irttp_udata_request()
just returns -1 in similar situations. Sync the two and the loglevels of the
accompanying output.
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Cc: Samuel Ortiz <sameo@linux.intel.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Expose reachable and retrans timer values in msecs instead of jiffies.
Both timer values are already exposed as msecs in the neighbour table
netlink interface.
The creation timestamp format with increased precision is kept but
cleaned up.
Signed-off-by: Thomas Graf <tgraf@infradead.org>
Cc: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
IFLA_PROTINFO exposes timer related per device settings in jiffies.
Change it to expose these values in msecs like the sysctl interface
does.
I did not find any users of IFLA_PROTINFO which rely on any of these
values and even if there are, they are likely already broken because
there is no way for them to reliably convert such a value to another
time format.
Signed-off-by: Thomas Graf <tgraf@infradead.org>
Cc: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
netif_set_real_num_rx_queues() can decrement and increment
the number of rx queues. For example ixgbe does this as
features and offloads are toggled. Presumably this could
also happen across down/up on most devices if the available
resources changed (cpu offlined).
The kobject needs to be zero'd in this case so that the
state is not preserved across kobject_put()/kobject_init_and_add().
This resolves the following error report.
ixgbe 0000:03:00.0: eth2: NIC Link is Up 10 Gbps, Flow Control: RX/TX
kobject (ffff880324b83210): tried to init an initialized object, something is seriously wrong.
Pid: 1972, comm: lldpad Not tainted 2.6.37-rc18021qaz+ #169
Call Trace:
[<ffffffff8121c940>] kobject_init+0x3a/0x83
[<ffffffff8121cf77>] kobject_init_and_add+0x23/0x57
[<ffffffff8107b800>] ? mark_lock+0x21/0x267
[<ffffffff813c6d11>] net_rx_queue_update_kobjects+0x63/0xc6
[<ffffffff813b5e0e>] netif_set_real_num_rx_queues+0x5f/0x78
[<ffffffffa0261d49>] ixgbe_set_num_queues+0x1c6/0x1ca [ixgbe]
[<ffffffffa0262509>] ixgbe_init_interrupt_scheme+0x1e/0x79c [ixgbe]
[<ffffffffa0274596>] ixgbe_dcbnl_set_state+0x167/0x189 [ixgbe]
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This follows wireless-testing 9236d838c9
("cfg80211: fix extension channel checks to initiate communication") and
fixes accidental case fall-through. Without this fix, HT40 is entirely
blocked.
Signed-off-by: Mark Mentovai <mark@moxienet.com>
Cc: stable@kernel.org
Acked-by: Luis R. Rodriguez <lrodriguez@atheros.com
Signed-off-by: John W. Linville <linville@tuxdriver.com>
In rds_cmsg_rdma_args(), the user-provided args->nr_local value is
restricted to less than UINT_MAX. This seems to need a tighter upper
bound, since the calculation of total iov_size can overflow, resulting
in a small sock_kmalloc() allocation. This would probably just result
in walking off the heap and crashing when calling rds_rdma_pages() with
a high count value. If it somehow doesn't crash here, then memory
corruption could occur soon after.
Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When operating in a mode that initiates communication and using
HT40 we should fail if we cannot use both primary and secondary
channels to initiate communication. Our current ht40 allowmap
only covers STA mode of operation, for beaconing modes we need
a check on the fly as the mode of operation is dynamic and
there other flags other than disable which we should read
to check if we can initiate communication.
Do not allow for initiating communication if our secondary HT40
channel has is either disabled, has a passive scan flag, a
no-ibss flag or is a radar channel. Userspace now has similar
checks but this is also needed in-kernel.
Reported-by: Jouni Malinen <jouni.malinen@atheros.com>
Cc: stable@kernel.org
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
otherwise xfrm_lookup will fail to find correct policy
Signed-off-by: Ulrich Weber <uweber@astaro.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Sending zero byte packets is not neccessarily an error (AF_INET accepts it,
too), so just apply a shortcut. This was discovered because of a non-working
software with WINE. See
http://bugs.winehq.org/show_bug.cgi?id=19397#c86http://thread.gmane.org/gmane.linux.irda.general/1643
for very detailed debugging information and a testcase. Kudos to Wolfgang for
those!
Reported-by: Wolfgang Schwotzer <wolfgang.schwotzer@gmx.net>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Tested-by: Mike Evans <mike.evans@cardolan.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (66 commits)
can-bcm: fix minor heap overflow
gianfar: Do not call device_set_wakeup_enable() under a spinlock
ipv6: Warn users if maximum number of routes is reached.
docs: Add neigh/gc_thresh3 and route/max_size documentation.
axnet_cs: fix resume problem for some Ax88790 chip
ipv6: addrconf: don't remove address state on ifdown if the address is being kept
tcp: Don't change unlocked socket state in tcp_v4_err().
x25: Prevent crashing when parsing bad X.25 facilities
cxgb4vf: add call to Firmware to reset VF State.
cxgb4vf: Fail open if link_start() fails.
cxgb4vf: flesh out PCI Device ID Table ...
cxgb4vf: fix some errors in Gather List to skb conversion
cxgb4vf: fix bug in Generic Receive Offload
cxgb4vf: don't implement trivial (and incorrect) ndo_select_queue()
ixgbe: Look inside vlan when determining offload protocol.
bnx2x: Look inside vlan when determining checksum proto.
vlan: Add function to retrieve EtherType from vlan packets.
virtio-net: init link state correctly
ucc_geth: Fix deadlock
ucc_geth: Do not bring the whole IF down when TX failure.
...
On 64-bit platforms the ASCII representation of a pointer may be up to 17
bytes long. This patch increases the length of the buffer accordingly.
http://marc.info/?l=linux-netdev&m=128872251418192&w=2
Reported-by: Dan Rosenberg <drosenberg@vsecurity.com>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
CC: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This gives users at least some clue as to what the problem
might be and how to go about fixing it.
Signed-off-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, addrconf_ifdown does not delete statically configured IPv6
addresses when the interface is brought down. The intent is that when
the interface comes back up the address will be usable again. However,
this doesn't actually work, because the system stops listening on the
corresponding solicited-node multicast address, so the address cannot
respond to neighbor solicitations and thus receive traffic. Also, the
code notifies the rest of the system that the address is being deleted
(e.g, RTM_DELADDR), even though it is not. Fix it so that none of this
state is updated if the address is being kept on the interface.
Tested: Added a statically configured IPv6 address to an interface,
started ping, brought link down, brought link up again. When link came
up ping kept on going and "ip -6 maddr" showed that the host was still
subscribed to there
Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Alexey Kuznetsov noticed a regression introduced by
commit f1ecd5d9e7
("Revert Backoff [v3]: Revert RTO on ICMP destination unreachable")
The RTO and timer modification code added to tcp_v4_err()
doesn't check sock_owned_by_user(), which if true means we
don't have exclusive access to the socket and therefore cannot
modify it's critical state.
Just skip this new code block if sock_owned_by_user() is true
and eliminate the now superfluous sock_owned_by_user() code
block contained within.
Reported-by: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
CC: Damian Lukowski <damian@tvk.rwth-aachen.de>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Now with improved comma support.
On parsing malformed X.25 facilities, decrementing the remaining length
may cause it to underflow. Since the length is an unsigned integer,
this will result in the loop continuing until the kernel crashes.
This patch adds checks to ensure decrementing the remaining length does
not cause it to wrap around.
Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
