getsockopt(..., SCTP_EVENTS, ...) performs a length check and returns
an error if the user provides less bytes than the size of struct
sctp_event_subscribe.
Struct sctp_event_subscribe needs to be extended by an u8 for every
new event or notification type that is added.
This obviously makes getsockopt fail for binaries that are compiled
against an older versions of <net/sctp/user.h> which do not contain
all event types.
This patch changes getsockopt behaviour to no longer return an error
if not enough bytes are being provided by the user. Instead, it
returns as much of sctp_event_subscribe as fits into the provided buffer.
This leads to the new behavior that users see what they have been aware
of at compile time.
The setsockopt(..., SCTP_EVENTS, ...) API is already behaving like this.
Signed-off-by: Thomas Graf <[email protected]>
Acked-by: Vlad Yasevich <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Trigger user ABORT if application closes a socket which has data
queued on the socket receive queue or chunks waiting on the
reassembly or ordering queue as this would imply data being lost
which defeats the point of a graceful shutdown.
This behavior is already practiced in TCP.
We do not check the input queue because that would mean to parse
all chunks on it to look for unacknowledged data which seems too
much of an effort. Control chunks or duplicated chunks may also
be in the input queue and should not be stopping a graceful
shutdown.
Signed-off-by: Thomas Graf <[email protected]>
Acked-by: Vlad Yasevich <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
When initiating a graceful shutdown while having data chunks
on the retransmission queue with a peer which is in zero
window mode the shutdown is never completed because the
retransmission error count is reset periodically by the
following two rules:
- Do not timeout association while doing zero window probe.
- Reset overall error count when a heartbeat request has
been acknowledged.
The graceful shutdown will wait for all outstanding TSN to
be acknowledged before sending the SHUTDOWN request. This
never happens due to the peer's zero window not acknowledging
the continuously retransmitted data chunks. Although the
error counter is incremented for each failed retransmission,
the receiving of the SACK announcing the zero window clears
the error count again immediately. Also heartbeat requests
continue to be sent periodically. The peer acknowledges these
requests causing the error counter to be reset as well.
This patch changes behaviour to only reset the overall error
counter for the above rules while not in shutdown. After
reaching the maximum number of retransmission attempts, the
T5 shutdown guard timer is scheduled to give the receiver
some additional time to recover. The timer is stopped as soon
as the receiver acknowledges any data.
The issue can be easily reproduced by establishing a sctp
association over the loopback device, constantly queueing
data at the sender while not reading any at the receiver.
Wait for the window to reach zero, then initiate a shutdown
by killing both processes simultaneously. The association
will never be freed and the chunks on the retransmission
queue will be retransmitted indefinitely.
Signed-off-by: Thomas Graf <[email protected]>
Acked-by: Vlad Yasevich <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
This patch adds a change sequence counter to each net namespace
which is bumped whenever a netdevice is added or removed from
the list. If such a change occurred while a link dump took place,
the dump will have the NLM_F_DUMP_INTR flag set in the first
message which has been interrupted and in all subsequent messages
of the same dump.
Note that links may still be modified or renamed while a dump is
taking place but we can guarantee for userspace to receive a
complete list of links and not miss any.
Testing:
I have added 500 VLAN netdevices to make sure the dump is split
over multiple messages. Then while continuously dumping links in
one process I also continuously deleted and re-added a dummy
netdevice in another process. Multiple dumps per seconds have
had the NLM_F_DUMP_INTR flag set.
I guess we can wait for Johannes patch to hit net-next via the
wireless tree. I just wanted to give this some testing right away.
Signed-off-by: Thomas Graf <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
exthdrs_core.c and addrconf_core.c in net/ipv6/ contain bits which
must be made available even if IPv6 is disabled.
net/ipv6/Makefile already correctly includes them if CONFIG_IPV6=n
but net/Makefile prevents entering the subdirectory.
Signed-off-by: Thomas Graf <[email protected]>
Acked-by: Randy Dunlap <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
The setsockopt() syscall to replace tables is already recorded
in the audit logs. This patch stores additional information
such as table name and netfilter protocol.
Cc: Patrick McHardy <[email protected]>
Cc: Eric Paris <[email protected]>
Cc: Al Viro <[email protected]>
Signed-off-by: Thomas Graf <[email protected]>
Signed-off-by: Patrick McHardy <[email protected]>
This patch adds a new netfilter target which creates audit records
for packets traversing a certain chain.
It can be used to record packets which are rejected administraively
as follows:
-N AUDIT_DROP
-A AUDIT_DROP -j AUDIT --type DROP
-A AUDIT_DROP -j DROP
a rule which would typically drop or reject a packet would then
invoke the new chain to record packets before dropping them.
-j AUDIT_DROP
The module is protocol independant and works for iptables, ip6tables
and ebtables.
The following information is logged:
- netfilter hook
- packet length
- incomming/outgoing interface
- MAC src/dst/proto for ethernet packets
- src/dst/protocol address for IPv4/IPv6
- src/dst port for TCP/UDP/UDPLITE
- icmp type/code
Cc: Patrick McHardy <[email protected]>
Cc: Eric Paris <[email protected]>
Cc: Al Viro <[email protected]>
Signed-off-by: Thomas Graf <[email protected]>
Signed-off-by: Patrick McHardy <[email protected]>
As David pointed out correctly, updates to af-specific attributes
are currently not atomic. If multiple changes are requested and
one of them fails, previous updates may have been applied already
leaving the link behind in a undefined state.
This patch splits the function parse_link_af() into two functions
validate_link_af() and set_link_at(). validate_link_af() is placed
to validate_linkmsg() check for errors as early as possible before
any changes to the link have been made. set_link_af() is called to
commit the changes later.
This method is not fail proof, while it is currently sufficient
to make set_link_af() inerrable and thus 100% atomic, the
validation function method will not be able to detect all error
scenarios in the future, there will likely always be errors
depending on states which are f.e. not protected by rtnl_mutex
and thus may change between validation and setting.
Also, instead of silently ignoring unknown address families and
config blocks for address families which did not register a set
function the errors EAFNOSUPPORT respectively EOPNOSUPPORT are
returned to avoid comitting 4 out of 5 update requests without
notifying the user.
Signed-off-by: Thomas Graf <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
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 <[email protected]>
Cc: YOSHIFUJI Hideaki <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
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 <[email protected]>
Cc: YOSHIFUJI Hideaki <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
IPv6 already exposes some address family data via netlink in the
IFLA_PROTINFO attribute if RTM_GETLINK request is sent with the
address family set to AF_INET6. We take over this format and
reuse all the code.
Signed-off-by: Thomas Graf <[email protected]>
Cc: YOSHIFUJI Hideaki <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Implements the AF_INET link address family exposing the per
device configuration settings via netlink using the attribute
IFLA_INET_CONF.
The format of IFLA_INET_CONF differs depending on the direction
the attribute is sent. The attribute sent by the kernel consists
of a u32 array, basically a 1:1 copy of in_device->cnf.data[].
The attribute expected by the kernel must consist of a sequence
of nested u32 attributes, each representing a change request,
e.g.
[IFLA_INET_CONF] = {
[IPV4_DEVCONF_FORWARDING] = 1,
[IPV4_DEVCONF_NOXFRM] = 0,
}
libnl userspace API documentation and example available from:
http://www.infradead.org/~tgr/libnl/doc-git/group__link__inet.html
Signed-off-by: Thomas Graf <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Define IPV4_DEVCONF_MAX to get rid of MAX - 1 notation.
Signed-off-by: Thomas Graf <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Each net_device contains address family specific data such as
per device settings and statistics. We already expose this data
via procfs/sysfs and partially netlink.
The netlink method requires the requester to send one RTM_GETLINK
request for each address family it wishes to receive data of
and then merge this data itself.
This patch implements a new API which combines all address family
specific link data in a new netlink attribute IFLA_AF_SPEC.
IFLA_AF_SPEC contains a sequence of nested attributes, one for each
address family which in turn defines the structure of its own
attribute. Example:
[IFLA_AF_SPEC] = {
[AF_INET] = {
[IFLA_INET_CONF] = ...,
},
[AF_INET6] = {
[IFLA_INET6_FLAGS] = ...,
[IFLA_INET6_CONF] = ...,
}
}
The API also allows for address families to implement a function
which parses the IFLA_AF_SPEC attribute sent by userspace to
implement address family specific link options.
Signed-off-by: Thomas Graf <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
nlmsg_total_size() calculates the length of a netlink message
including header and alignment. nla_total_size() calculates the
space an individual attribute consumes which was meant to be used
in this context.
Also, ensure to account for the attribute header for the
IFLA_INFO_XSTATS attribute as implementations of get_xstats_size()
seem to assume that we do so.
The addition of two message headers minus the missing attribute
header resulted in a calculated message size that was larger than
required. Therefore we never risked running out of skb tailroom.
Signed-off-by: Thomas Graf <[email protected]>
Acked-by: Patrick McHardy <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
While validating the configuration em_ops is already set, thus the
individual destroy functions are called, but the ematch data has
not been allocated and associated with the ematch yet.
Signed-off-by: Thomas Graf <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Documentation for recent changes to the tunables accept_ra and
forwarding.
Signed-off-by: Thomas Graf <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Similar to accepting router advertisement, the IPv6 stack does not send router
solicitations if forwarding is enabled.
This patch enables this behavior to be overruled by setting forwarding to the
special value 2.
Signed-off-by: Thomas Graf <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
The current IPv6 behavior is to not accept router advertisements while
forwarding, i.e. configured as router.
This does make sense, a router is typically not supposed to be auto
configured. However there are exceptions and we should allow the
current behavior to be overwritten.
Therefore this patch enables the user to overrule the "if forwarding
enabled then don't listen to RAs" rule by setting accept_ra to the
special value of 2.
An alternative would be to ignore the forwarding switch alltogether
and solely accept RAs based on the value of accept_ra. However, I
found that if not intended, accepting RAs as a router can lead to
strange unwanted behavior therefore we it seems wise to only do so
if the user explicitely asks for this behavior.
Signed-off-by: Thomas Graf <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
Thomas Graf