Similiar with ipv6 mcast commit 89225d1ce6 ("net: ipv6: mld: fix v1/v2
switchback timeout to rfc3810, 9.12.")
i) RFC3376 8.12. Older Version Querier Present Timeout says:
The Older Version Querier Interval is the time-out for transitioning
a host back to IGMPv3 mode once an older version query is heard.
When an older version query is received, hosts set their Older
Version Querier Present Timer to Older Version Querier Interval.
This value MUST be ((the Robustness Variable) times (the Query
Interval in the last Query received)) plus (one Query Response
Interval).
Currently we only use a hardcode value IGMP_V1/v2_ROUTER_PRESENT_TIMEOUT.
Fix it by adding two new items mr_qi(Query Interval) and mr_qri(Query Response
Interval) in struct in_device.
Now we can calculate the switchback time via (mr_qrv * mr_qi) + mr_qri.
We need update these values when receive IGMPv3 queries.
Reported-by: Ying Xu <yinxu@redhat.com>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
After link down and up, i.e. when call ip_mc_up(), we doesn't init
im->unsolicit_count. So after igmp_timer_expire(), we will not start
timer again and only send one unsolicit report at last.
Fix it by initializing im->unsolicit_count in igmp_group_added(), so
we can respect igmp robustness value.
Fixes: 24803f38a5 ("igmp: do not remove igmp souce list info when set link down")
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We should not start timer if im->unsolicit_count equal to 0 after decrease.
Or we will send one more unsolicit report message. i.e. 3 instead of 2 by
default.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The BTF conflicts were simple overlapping changes.
The virtio_net conflict was an overlap of a fix of statistics counter,
happening alongisde a move over to a bonafide statistics structure
rather than counting value on the stack.
Signed-off-by: David S. Miller <davem@davemloft.net>
Fixes the following sparse warnings:
net/ipv4/igmp.c:1391:6: warning:
symbol '__ip_mc_inc_group' was not declared. Should it be static?
Fixes: 6e2059b53f ("ipv4/igmp: init group mode as INCLUDE when join source group")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There are two scenarios that we will restore deleted records. The first is
when device down and up(or unmap/remap). In this scenario the new filter
mode is same with previous one. Because we get it from in_dev->mc_list and
we do not touch it during device down and up.
The other scenario is when a new socket join a group which was just delete
and not finish sending status reports. In this scenario, we should use the
current filter mode instead of restore old one. Here are 4 cases in total.
old_socket new_socket before_fix after_fix
IN(A) IN(A) ALLOW(A) ALLOW(A)
IN(A) EX( ) TO_IN( ) TO_EX( )
EX( ) IN(A) TO_EX( ) ALLOW(A)
EX( ) EX( ) TO_EX( ) TO_EX( )
Fixes: 24803f38a5 (igmp: do not remove igmp souce list info when set link down)
Fixes: 1666d49e1d (mld: do not remove mld souce list info when set link down)
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove the mode parameter for igmp/igmp6_group_added as we can get it
from first parameter.
Fixes: 6e2059b53f (ipv4/igmp: init group mode as INCLUDE when join source group)
Fixes: c7ea20c9da (ipv6/mcast: init as INCLUDE when join SSM INCLUDE group)
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Based on RFC3376 5.1
If no interface
state existed for that multicast address before the change (i.e., the
change consisted of creating a new per-interface record), or if no
state exists after the change (i.e., the change consisted of deleting
a per-interface record), then the "non-existent" state is considered
to have a filter mode of INCLUDE and an empty source list.
Which means a new multicast group should start with state IN().
Function ip_mc_join_group() works correctly for IGMP ASM(Any-Source Multicast)
mode. It adds a group with state EX() and inits crcount to mc_qrv,
so the kernel will send a TO_EX() report message after adding group.
But for IGMPv3 SSM(Source-specific multicast) JOIN_SOURCE_GROUP mode, we
split the group joining into two steps. First we join the group like ASM,
i.e. via ip_mc_join_group(). So the state changes from IN() to EX().
Then we add the source-specific address with INCLUDE mode. So the state
changes from EX() to IN(A).
Before the first step sends a group change record, we finished the second
step. So we will only send the second change record. i.e. TO_IN(A).
Regarding the RFC stands, we should actually send an ALLOW(A) message for
SSM JOIN_SOURCE_GROUP as the state should mimic the 'IN() to IN(A)'
transition.
The issue was exposed by commit a052517a8f ("net/multicast: should not
send source list records when have filter mode change"). Before this change,
we used to send both ALLOW(A) and TO_IN(A). After this change we only send
TO_IN(A).
Fix it by adding a new parameter to init group mode. Also add new wrapper
functions so we don't need to change too much code.
v1 -> v2:
In my first version I only cleared the group change record. But this is not
enough. Because when a new group join, it will init as EXCLUDE and trigger
an filter mode change in ip/ip6_mc_add_src(), which will clear all source
addresses' sf_crcount. This will prevent early joined address sending state
change records if multi source addressed joined at the same time.
In v2 patch, I fixed it by directly initializing the mode to INCLUDE for SSM
JOIN_SOURCE_GROUP. I also split the original patch into two separated patches
for IPv4 and IPv6.
Fixes: a052517a8f ("net/multicast: should not send source list records when have filter mode change")
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Variants of proc_create{,_data} that directly take a struct seq_operations
and deal with network namespaces in ->open and ->release. All callers of
proc_create + seq_open_net converted over, and seq_{open,release}_net are
removed entirely.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Synchronous pernet_operations are not allowed anymore.
All are asynchronous. So, drop the structure member.
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Prefer the direct use of octal for permissions.
Done with checkpatch -f --types=SYMBOLIC_PERMS --fix-inplace
and some typing.
Miscellanea:
o Whitespace neatening around these conversions.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
arp_net_ops just addr/removes /proc entry.
devinet_ops allocates and frees duplicate of init_net tables
and (un)registers sysctl entries.
fib_net_ops allocates and frees pernet tables, creates/destroys
netlink socket and (un)initializes /proc entries. Foreign
pernet_operations do not touch them.
ip_rt_proc_ops only modifies pernet /proc entries.
xfrm_net_ops creates/destroys /proc entries, allocates/frees
pernet statistics, hashes and tables, and (un)initializes
sysctl files. These are not touched by foreigh pernet_operations
xfrm4_net_ops allocates/frees private pernet memory, and
configures sysctls.
sysctl_route_ops creates/destroys sysctls.
rt_genid_ops only initializes fields of just allocated net.
ipv4_inetpeer_ops allocated/frees net private memory.
igmp_net_ops just creates/destroys /proc files and socket,
noone else interested in.
tcp_sk_ops seems to be safe, because tcp_sk_init() does not
depend on any other pernet_operations modifications. Iteration
over hash table in inet_twsk_purge() is made under RCU lock,
and it's safe to iterate the table this way. Removing from
the table happen from inet_twsk_deschedule_put(), but this
function is safe without any extern locks, as it's synchronized
inside itself. There are many examples, it's used in different
context. So, it's safe to leave tcp_sk_exit_batch() unlocked.
tcp_net_metrics_ops is synchronized on tcp_metrics_lock and safe.
udplite4_net_ops only creates/destroys pernet /proc file.
icmp_sk_ops creates percpu sockets, not touched by foreign
pernet_operations.
ipmr_net_ops creates/destroys pernet fib tables, (un)registers
fib rules and /proc files. This seem to be safe to execute
in parallel with foreign pernet_operations.
af_inet_ops just sets up default parameters of newly created net.
ipv4_mib_ops creates and destroys pernet percpu statistics.
raw_net_ops, tcp4_net_ops, udp4_net_ops, ping_v4_net_ops
and ip_proc_ops only create/destroy pernet /proc files.
ip4_frags_ops creates and destroys sysctl file.
So, it's safe to make the pernet_operations async.
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Acked-by: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
en_rx_am.c was deleted in 'net-next' but had a bug fixed in it in
'net'.
The esp{4,6}_offload.c conflicts were overlapping changes.
The 'out' label is removed so we just return ERR_PTR(-EINVAL)
directly.
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit "net: igmp: Use correct source address on IGMPv3 reports"
introduced a check to validate the source address of locally generated
IGMPv3 packets.
Instead of checking the local interface address directly, it uses
inet_ifa_match(fl4->saddr, ifa), which checks if the address is on the
local subnet (or equal to the point-to-point address if used).
This breaks for point-to-point interfaces, so check against
ifa->ifa_local directly.
Cc: Kevin Cernekee <cernekee@chromium.org>
Fixes: a46182b002 ("net: igmp: Use correct source address on IGMPv3 reports")
Reported-by: Sebastian Gottschall <s.gottschall@dd-wrt.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: David S. Miller <davem@davemloft.net>
/proc has been ignoring struct file_operations::owner field for 10 years.
Specifically, it started with commit 786d7e1612
("Fix rmmod/read/write races in /proc entries"). Notice the chunk where
inode->i_fop is initialized with proxy struct file_operations for
regular files:
- if (de->proc_fops)
- inode->i_fop = de->proc_fops;
+ if (de->proc_fops) {
+ if (S_ISREG(inode->i_mode))
+ inode->i_fop = &proc_reg_file_ops;
+ else
+ inode->i_fop = de->proc_fops;
+ }
VFS stopped pinning module at this point.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Closing a multicast socket after the final IPv4 address is deleted
from an interface can generate a membership report that uses the
source IP from a different interface. The following test script, run
from an isolated netns, reproduces the issue:
#!/bin/bash
ip link add dummy0 type dummy
ip link add dummy1 type dummy
ip link set dummy0 up
ip link set dummy1 up
ip addr add 10.1.1.1/24 dev dummy0
ip addr add 192.168.99.99/24 dev dummy1
tcpdump -U -i dummy0 &
socat EXEC:"sleep 2" \
UDP4-DATAGRAM:239.101.1.68:8889,ip-add-membership=239.0.1.68:10.1.1.1 &
sleep 1
ip addr del 10.1.1.1/24 dev dummy0
sleep 5
kill %tcpdump
RFC 3376 specifies that the report must be sent with a valid IP source
address from the destination subnet, or from address 0.0.0.0. Add an
extra check to make sure this is the case.
Signed-off-by: Kevin Cernekee <cernekee@chromium.org>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
IPv4 stack reacts to changes to small MTU, by disabling itself under
RTNL.
But there is a window where threads not using RTNL can see a wrong
device mtu. This can lead to surprises, in igmp code where it is
assumed the mtu is suitable.
Fix this by reading device mtu once and checking IPv4 minimal MTU.
This patch adds missing IPV4_MIN_MTU define, to not abuse
ETH_MIN_MTU anymore.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Anuradha reported that statically added groups for interfaces enslaved
to a VRF device were not persisting. The problem is that igmp queries
and reports need to use the data in the in_dev for the real ingress
device rather than the VRF device. Update igmp_rcv accordingly.
Fixes: e58e415968 ("net: Enable support for VRF with ipv4 multicast")
Reported-by: Anuradha Karuppiah <anuradhak@cumulusnetworks.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Reviewed-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Mainline had UFO fixes, but UFO is removed in net-next so we
take the HEAD hunks.
Minor context conflict in bcmsysport statistics bug fix.
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit dcd87999d4 ("igmp: net: Move igmp namespace init to correct file")
moved the igmp sysctls initialization from tcp_sk_init to igmp_net_init. This
function is only called as part of per-namespace initialization, only if
CONFIG_IP_MULTICAST is defined, otherwise igmp_mc_init() call in ip_init is
compiled out, casuing the igmp pernet ops to not be registerd and those sysctl
being left initialized with 0. However, there are certain functions, such as
ip_mc_join_group which are always compiled and make use of some of those
sysctls. Let's do a partial revert of the aforementioned commit and move the
sysctl initialization into inet_init_net, that way they will always have
sane values.
Fixes: dcd87999d4 ("igmp: net: Move igmp namespace init to correct file")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=196595
Reported-by: Gerardo Exequiel Pozzi <vmlinuz386@gmail.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Two entries being added at the same time to the IFLA
policy table, whilst parallel bug fixes to decnet
routing dst handling overlapping with the dst gc removal
in net-next.
Signed-off-by: David S. Miller <davem@davemloft.net>
Andrey reported a lockdep warning on non-initialized
spinlock:
INFO: trying to register non-static key.
the code is fine but needs lockdep annotation.
turning off the locking correctness validator.
CPU: 1 PID: 4099 Comm: a.out Not tainted 4.12.0-rc6+ #9
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:16
dump_stack+0x292/0x395 lib/dump_stack.c:52
register_lock_class+0x717/0x1aa0 kernel/locking/lockdep.c:755
? 0xffffffffa0000000
__lock_acquire+0x269/0x3690 kernel/locking/lockdep.c:3255
lock_acquire+0x22d/0x560 kernel/locking/lockdep.c:3855
__raw_spin_lock_bh ./include/linux/spinlock_api_smp.h:135
_raw_spin_lock_bh+0x36/0x50 kernel/locking/spinlock.c:175
spin_lock_bh ./include/linux/spinlock.h:304
ip_mc_clear_src+0x27/0x1e0 net/ipv4/igmp.c:2076
igmpv3_clear_delrec+0xee/0x4f0 net/ipv4/igmp.c:1194
ip_mc_destroy_dev+0x4e/0x190 net/ipv4/igmp.c:1736
We miss a spin_lock_init() in igmpv3_add_delrec(), probably
because previously we never use it on this code path. Since
we already unlink it from the global mc_tomb list, it is
probably safe not to acquire this spinlock here. It does not
harm to have it although, to avoid conditional locking.
Fixes: c38b7d327a ("igmp: acquire pmc lock for ip_mc_clear_src()")
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It seems like a historic accident that these return unsigned char *,
and in many places that means casts are required, more often than not.
Make these functions (skb_put, __skb_put and pskb_put) return void *
and remove all the casts across the tree, adding a (u8 *) cast only
where the unsigned char pointer was used directly, all done with the
following spatch:
@@
expression SKB, LEN;
typedef u8;
identifier fn = { skb_put, __skb_put };
@@
- *(fn(SKB, LEN))
+ *(u8 *)fn(SKB, LEN)
@@
expression E, SKB, LEN;
identifier fn = { skb_put, __skb_put };
type T;
@@
- E = ((T *)(fn(SKB, LEN)))
+ E = fn(SKB, LEN)
which actually doesn't cover pskb_put since there are only three
users overall.
A handful of stragglers were converted manually, notably a macro in
drivers/isdn/i4l/isdn_bsdcomp.c and, oddly enough, one of the many
instances in net/bluetooth/hci_sock.c. In the former file, I also
had to fix one whitespace problem spatch introduced.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Andrey reported a use-after-free in add_grec():
for (psf = *psf_list; psf; psf = psf_next) {
...
psf_next = psf->sf_next;
where the struct ip_sf_list's were already freed by:
kfree+0xe8/0x2b0 mm/slub.c:3882
ip_mc_clear_src+0x69/0x1c0 net/ipv4/igmp.c:2078
ip_mc_dec_group+0x19a/0x470 net/ipv4/igmp.c:1618
ip_mc_drop_socket+0x145/0x230 net/ipv4/igmp.c:2609
inet_release+0x4e/0x1c0 net/ipv4/af_inet.c:411
sock_release+0x8d/0x1e0 net/socket.c:597
sock_close+0x16/0x20 net/socket.c:1072
This happens because we don't hold pmc->lock in ip_mc_clear_src()
and a parallel mr_ifc_timer timer could jump in and access them.
The RCU lock is there but it is merely for pmc itself, this
spinlock could actually ensure we don't access them in parallel.
Thanks to Eric and Long for discussion on this bug.
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Xin Long <lucien.xin@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Reviewed-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In function igmpv3/mld_add_delrec() we allocate pmc and put it in
idev->mc_tomb, so we should free it when we don't need it in del_delrec().
But I removed kfree(pmc) incorrectly in latest two patches. Now fix it.
Fixes: 24803f38a5 ("igmp: do not remove igmp souce list info when ...")
Fixes: 1666d49e1d ("mld: do not remove mld souce list info when ...")
Reported-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
5.2. Action on Reception of a Query
When a system receives a Query, it does not respond immediately.
Instead, it delays its response by a random amount of time, bounded
by the Max Resp Time value derived from the Max Resp Code in the
received Query message. A system may receive a variety of Queries on
different interfaces and of different kinds (e.g., General Queries,
Group-Specific Queries, and Group-and-Source-Specific Queries), each
of which may require its own delayed response.
Before scheduling a response to a Query, the system must first
consider previously scheduled pending responses and in many cases
schedule a combined response. Therefore, the system must be able to
maintain the following state:
o A timer per interface for scheduling responses to General Queries.
o A per-group and interface timer for scheduling responses to Group-
Specific and Group-and-Source-Specific Queries.
o A per-group and interface list of sources to be reported in the
response to a Group-and-Source-Specific Query.
When a new Query with the Router-Alert option arrives on an
interface, provided the system has state to report, a delay for a
response is randomly selected in the range (0, [Max Resp Time]) where
Max Resp Time is derived from Max Resp Code in the received Query
message. The following rules are then used to determine if a Report
needs to be scheduled and the type of Report to schedule. The rules
are considered in order and only the first matching rule is applied.
1. If there is a pending response to a previous General Query
scheduled sooner than the selected delay, no additional response
needs to be scheduled.
2. If the received Query is a General Query, the interface timer is
used to schedule a response to the General Query after the
selected delay. Any previously pending response to a General
Query is canceled.
--8<--
Currently the timer is rearmed with new random expiration time for
every incoming query regardless of possibly already pending report.
Which is not aligned with the above RFE.
It also might happen that higher rate of incoming queries can
postpone the report after the expiration time of the first query
causing group membership loss.
Now the per interface general query timer is rearmed only
when there is no pending report already scheduled on that interface or
the newly selected expiration time is before the already pending
scheduled report.
Signed-off-by: Michal Tesar <mtesar@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This was entirely automated, using the script by Al:
PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
$(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)
to do the replacement at the end of the merge window.
Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In commit 24cf3af3fe ("igmp: call ip_mc_clear_src..."), we forgot to remove
igmpv3_clear_delrec() in ip_mc_down(), which also called ip_mc_clear_src().
This make us clear all IGMPv3 source filter info after NETDEV_DOWN.
Move igmpv3_clear_delrec() to ip_mc_destroy_dev() and then no need
ip_mc_clear_src() in ip_mc_destroy_dev().
On the other hand, we should restore back instead of free all source filter
info in igmpv3_del_delrec(). Or we will not able to restore IGMPv3 source
filter info after NETDEV_UP and NETDEV_POST_TYPE_CHANGE.
Fixes: 24cf3af3fe ("igmp: call ip_mc_clear_src() only when ...")
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Based on RFC3376 5.1 and RFC3810 6.1
If the per-interface listening change that triggers the new report is
a filter mode change, then the next [Robustness Variable] State
Change Reports will include a Filter Mode Change Record. This
applies even if any number of source list changes occur in that
period.
Old State New State State Change Record Sent
--------- --------- ------------------------
INCLUDE (A) EXCLUDE (B) TO_EX (B)
EXCLUDE (A) INCLUDE (B) TO_IN (B)
So we should not send source-list change if there is a filter-mode change.
Here are two scenarios:
1. Group deleted and filter mode is EXCLUDE, which means we need send a
TO_IN { }.
2. Not group deleted, but has pcm->crcount, which means we need send a
normal filter-mode-change.
At the same time, if the type is ALLOW or BLOCK, and have psf->sf_crcount,
we stop add records and decrease sf_crcount directly
Reference: https://www.ietf.org/mail-archive/web/magma/current/msg01274.html
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Several cases of overlapping changes, as well as one instance
(vxlan) of a bug fix in 'net' overlapping with code movement
in 'net-next'.
Signed-off-by: David S. Miller <davem@davemloft.net>
The current reserved_tailroom calculation fails to take hlen and tlen into
account.
skb:
[__hlen__|__data____________|__tlen___|__extra__]
^ ^
head skb_end_offset
In this representation, hlen + data + tlen is the size passed to alloc_skb.
"extra" is the extra space made available in __alloc_skb because of
rounding up by kmalloc. We can reorder the representation like so:
[__hlen__|__data____________|__extra__|__tlen___]
^ ^
head skb_end_offset
The maximum space available for ip headers and payload without
fragmentation is min(mtu, data + extra). Therefore,
reserved_tailroom
= data + extra + tlen - min(mtu, data + extra)
= skb_end_offset - hlen - min(mtu, skb_end_offset - hlen - tlen)
= skb_tailroom - min(mtu, skb_tailroom - tlen) ; after skb_reserve(hlen)
Compare the second line to the current expression:
reserved_tailroom = skb_end_offset - min(mtu, skb_end_offset)
and we can see that hlen and tlen are not taken into account.
The min() in the third line can be expanded into:
if mtu < skb_tailroom - tlen:
reserved_tailroom = skb_tailroom - mtu
else:
reserved_tailroom = tlen
Depending on hlen, tlen, mtu and the number of multicast address records,
the current code may output skbs that have less tailroom than
dev->needed_tailroom or it may output more skbs than needed because not all
space available is used.
Fixes: 4c672e4b ("ipv6: mld: fix add_grhead skb_over_panic for devs with large MTUs")
Signed-off-by: Benjamin Poirier <bpoirier@suse.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
When igmp related sysctl were namespacified their initializatin was
erroneously put into the tcp socket namespace constructor. This
patch moves the relevant code into the igmp namespace constructor to
keep things consistent.
Also sprinkle some #ifdefs to silence warnings
Signed-off-by: Nikolay Borisov <kernel@kyup.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This was initially introduced in df2cf4a78e ("IGMP: Inhibit
reports for local multicast groups") by defining the sysctl in the
ipv4_net_table array, however it was never implemented to be
namespace aware. Fix this by changing the code accordingly.
Signed-off-by: David S. Miller <davem@davemloft.net>
When a multicast group is joined on a socket, a struct ip_mc_socklist
is appended to the sockets mc_list containing information about the
joined group.
If the interface is hot unplugged, this entry becomes stale. Prior to
commit 52ad353a53 ("igmp: fix the problem when mc leave group") it
was possible to remove the stale entry by performing a
IP_DROP_MEMBERSHIP, passing either the old ifindex or ip address on
the interface. However, this fix enforces that the interface must
still exist. Thus with time, the number of stale entries grows, until
sysctl_igmp_max_memberships is reached and then it is not possible to
join and more groups.
The previous patch fixes an issue where a IP_DROP_MEMBERSHIP is
performed without specifying the interface, either by ifindex or ip
address. However here we do supply one of these. So loosen the
restriction on device existence to only apply when the interface has
not been specified. This then restores the ability to clean up the
stale entries.
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Fixes: 52ad353a53 "(igmp: fix the problem when mc leave group")
Signed-off-by: David S. Miller <davem@davemloft.net>
Sasha reported the following lockdep warning:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(sk_lock-AF_INET);
lock(rtnl_mutex);
lock(sk_lock-AF_INET);
lock(rtnl_mutex);
This is due to that for IP_MSFILTER and MCAST_MSFILTER, we take
rtnl lock before the socket lock in setsockopt() path, but take
the socket lock before rtnl lock in getsockopt() path. All the
rest optnames are setsockopt()-only.
Fix this by aligning the getsockopt() path with the setsockopt()
path, so that all mcast socket path would be locked in the same
order.
Note, IPv6 part is different where rtnl lock is not held.
Fixes: 54ff9ef36b ("ipv4, ipv6: kill ip_mc_{join, leave}_group and ipv6_sock_mc_{join, drop}")
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It is confusing and silly hiding a parameter so modify all of
the callers to pass in the appropriate socket or skb->sk if
no socket is known.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch updates ip_check_mc_rcu so that protocol is passed as a u8
instead of a u16.
The motivation is just to avoid any unneeded type transitions since some
systems will require an instruction to zero extend a u8 field to a u16.
Also it makes it a bit more readable as to the fact that protocol is a u8
so there are no byte ordering changes needed to pass it.
Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The range of addresses between 224.0.0.0 and 224.0.0.255 inclusive, is
reserved for the use of routing protocols and other low-level topology
discovery or maintenance protocols, such as gateway discovery and
group membership reporting. Multicast routers should not forward any
multicast datagram with destination addresses in this range,
regardless of its TTL.
Currently, IGMP reports are generated for this reserved range of
addresses even though a router will ignore this information since it
has no purpose. However, the presence of reserved group addresses in
an IGMP membership report uses up network bandwidth and can also
obscure addresses of interest when inspecting membership reports using
packet inspection or debug messages.
Although the RFCs for the various version of IGMP (e.g.RFC 3376 for
v3) do not specify that the reserved addresses be excluded from
membership reports, it should do no harm in doing so. In particular
there should be no adverse effect in any IGMP snooping functionality
since 224.0.0.x is specifically excluded as per RFC 4541 (IGMP and MLD
Snooping Switches Considerations) section 2.1.2. Data Forwarding
Rules:
2) Packets with a destination IP (DIP) address in the 224.0.0.X
range which are not IGMP must be forwarded on all ports.
IGMP reports for local multicast groups can now be optionally
inhibited by means of a system control variable (by setting the value
to zero) e.g.:
echo 0 > /proc/sys/net/ipv4/igmp_link_local_mcast_reports
To retain backwards compatibility the previous behaviour is retained
by default on system boot or reverted by setting the value back to
non-zero e.g.:
echo 1 > /proc/sys/net/ipv4/igmp_link_local_mcast_reports
Signed-off-by: Philip Downey <pdowney@brocade.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The recent refactoring of the IGMP and MLD parsing code into
ipv6_mc_check_mld() / ip_mc_check_igmp() introduced a potential crash /
BUG() invocation for bridges:
I wrongly assumed that skb_get() could be used as a simple reference
counter for an skb which is not the case. skb_get() bears additional
semantics, a user count. This leads to a BUG() invocation in
pskb_expand_head() / kernel panic if pskb_may_pull() is called on an skb
with a user count greater than one - unfortunately the refactoring did
just that.
Fixing this by removing the skb_get() call and changing the API: The
caller of ipv6_mc_check_mld() / ip_mc_check_igmp() now needs to
additionally check whether the returned skb_trimmed is a clone.
Fixes: 9afd85c9e4 ("net: Export IGMP/MLD message validation code")
Reported-by: Brenden Blanco <bblanco@plumgrid.com>
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
With this patch, the IGMP and MLD message validation functions are moved
from the bridge code to IPv4/IPv6 multicast files. Some small
refactoring was done to enhance readibility and to iron out some
differences in behaviour between the IGMP and MLD parsing code (e.g. the
skb-cloning of MLD messages is now only done if necessary, just like the
IGMP part always did).
Finally, these IGMP and MLD message validation functions are exported so
that not only the bridge can use it but batman-adv later, too.
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: David S. Miller <davem@davemloft.net>
Hangbin Liu