Pablo Neira Ayuso says:
====================
Netfilter fixes for net
The following patchset contains Netfilter fixes for your net tree,
they are:
* Fix nf_trace in nftables if XT_TRACE=n, from Florian Westphal.
* Don't use the fast payload operation in nf_tables if the length is
not power of 2 or it is not aligned, from Nikolay Aleksandrov.
* Fix missing break statement the inet flavour of nft_reject, which
results in evaluating IPv4 packets with the IPv6 evaluation routine,
from Patrick McHardy.
* Fix wrong kconfig symbol in nft_meta to match the routing realm,
from Paul Bolle.
* Allocate the NAT null binding when creating new conntracks via
ctnetlink to avoid that several packets race at initializing the
the conntrack NAT extension, original patch from Florian Westphal,
revisited version from me.
* Fix DNAT handling in the snmp NAT helper, the same handling was being
done for SNAT and DNAT and 2.4 already contains that fix, from
Francois-Xavier Le Bail.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
When using nftables with CONFIG_NETFILTER_XT_TARGET_TRACE=n, we get
lots of "TRACE: filter:output:policy:1 IN=..." warnings as several
places will leave skb->nf_trace uninitialised.
Unlike iptables tracing functionality is not conditional in nftables,
so always copy/zero nf_trace setting when nftables is enabled.
Move this into __nf_copy() helper.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Marcelo Ricardo Leitner reported problems when the forwarding link path
has a lower mtu than the incoming one if the inbound interface supports GRO.
Given:
Host <mtu1500> R1 <mtu1200> R2
Host sends tcp stream which is routed via R1 and R2. R1 performs GRO.
In this case, the kernel will fail to send ICMP fragmentation needed
messages (or pkt too big for ipv6), as GSO packets currently bypass dstmtu
checks in forward path. Instead, Linux tries to send out packets exceeding
the mtu.
When locking route MTU on Host (i.e., no ipv4 DF bit set), R1 does
not fragment the packets when forwarding, and again tries to send out
packets exceeding R1-R2 link mtu.
This alters the forwarding dstmtu checks to take the individual gso
segment lengths into account.
For ipv6, we send out pkt too big error for gso if the individual
segments are too big.
For ipv4, we either send icmp fragmentation needed, or, if the DF bit
is not set, perform software segmentation and let the output path
create fragments when the packet is leaving the machine.
It is not 100% correct as the error message will contain the headers of
the GRO skb instead of the original/segmented one, but it seems to
work fine in my (limited) tests.
Eric Dumazet suggested to simply shrink mss via ->gso_size to avoid
sofware segmentation.
However it turns out that skb_segment() assumes skb nr_frags is related
to mss size so we would BUG there. I don't want to mess with it considering
Herbert and Eric disagree on what the correct behavior should be.
Hannes Frederic Sowa notes that when we would shrink gso_size
skb_segment would then also need to deal with the case where
SKB_MAX_FRAGS would be exceeded.
This uses sofware segmentation in the forward path when we hit ipv4
non-DF packets and the outgoing link mtu is too small. Its not perfect,
but given the lack of bug reports wrt. GRO fwd being broken this is a
rare case anyway. Also its not like this could not be improved later
once the dust settles.
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Reported-by: Marcelo Ricardo Leitner <mleitner@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
This moves part of Eric Dumazets skb_gso_seglen helper from tbf sched to
skbuff core so it may be reused by upcoming ip forwarding path patch.
Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Function to just return skb->rxhash without checking to see if it needs
to be recomputed.
Signed-off-by: Tom Herbert <therbert@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds a function to set up the partial checksum offset for IP
packets (and optionally re-calculate the pseudo-header checksum) into the
core network code.
The implementation was previously private and duplicated between xen-netback
and xen-netfront, however it is not xen-specific and is potentially useful
to any network driver.
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Veaceslav Falico <vfalico@redhat.com>
Cc: Alexander Duyck <alexander.h.duyck@intel.com>
Cc: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We should const-ify comparisons on skb_queue_* inline helper
functions as their parameters are const as well, so lets not
drop that.
Suggested-by: Brad Spengler <spender@grsecurity.net>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Jesse Gross says:
====================
[GIT net-next] Open vSwitch
Open vSwitch changes for net-next/3.14. Highlights are:
* Performance improvements in the mechanism to get packets to userspace
using memory mapped netlink and skb zero copy where appropriate.
* Per-cpu flow stats in situations where flows are likely to be shared
across CPUs. Standard flow stats are used in other situations to save
memory and allocation time.
* A handful of code cleanups and rationalization.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Make the skb zerocopy logic written for nfnetlink queue available for
use by other modules.
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Reviewed-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Jesse Gross <jesse@nicira.com>
Conflicts:
drivers/net/ethernet/qlogic/qlcnic/qlcnic_sriov_pf.c
net/ipv6/ip6_tunnel.c
net/ipv6/ip6_vti.c
ipv6 tunnel statistic bug fixes conflicting with consolidation into
generic sw per-cpu net stats.
qlogic conflict between queue counting bug fix and the addition
of multiple MAC address support.
Signed-off-by: David S. Miller <davem@davemloft.net>
We've seen so many instances of people invoking skb_tx_timestamp()
after the device already has been given the packet, that it's worth
being a little bit more verbose and explicit in this comment.
Signed-off-by: David S. Miller <davem@davemloft.net>
It can be a bit confusing when looking for checksumming flags that
the actual comment for this resides elsewhere further below in the
header file.
Thus, bring the documentation where we define these flags, and
slightly improve the doc text to make it a bit more clear/readable.
Also, whitespace-align values of the define while at it.
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ipgre_header_parse() needs to parse the tunnel's ip header and it
uses mac_header to locate the iphdr. This got broken when gre tunneling
was refactored as mac_header is no longer updated to point to iphdr.
Introduce skb_pop_mac_header() helper to do the mac_header assignment
and use it in ipgre_rcv() to fix msg_name parsing.
Bug introduced in commit c544193214 (GRE: Refactor GRE tunneling code.)
Cc: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: Timo Teräs <timo.teras@iki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
Adds skb_copy_hash to copy rxhash and l4_rxhash from one skb to another.
Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The function skb_set_rxash was added for drivers to call to set
the rxhash in an skb. The type of hash is also specified as
a parameter (L2, L3, L4, or unknown type).
Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In several places 'skb->rxhash = 0' is being done to clear the
rxhash value in an skb. This does not clear l4_rxhash which could
still be set so that the rxhash wouldn't be recalculated on subsequent
call to skb_get_rxhash. This patch adds an explict function to clear
all the rxhash related information in the skb properly.
skb_clear_hash_if_not_l4 clears the rxhash only if it is not marked as
l4_rxhash.
Fixed up places where 'skb->rxhash = 0' was being called.
Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Changing name of function as part of making the hash in skbuff to be
generic property, not just for receive path.
Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As we need it elsewhere, move the inline helper function of
skb_needs_linearize() over to skbuff.h include file. While
at it, also convert the return to 'bool' instead of 'int'
and add a proper kernel doc.
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This reverts commit 018c5bba05.
It causes regressions for people using chips driven by the sungem
driver. Suspicion is that the skb->csum value isn't being adjusted
properly.
The change also has a bug in that if __pskb_trim() fails, we'll leave
a corruped skb->csum value in there. We would really need to revert
it to it's original value in that case.
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently pskb_trim_rcsum() just balks on CHECKSUM_COMPLETE packets
and remarks them as CHECKSUM_NONE, forcing a software checksum
validation later.
We have all of the mechanics available to fixup the skb->csum value,
even for complicated fragmented packets, via the helpers
skb_checksum() and csum_sub().
So just use them.
Based upon a suggestion by Herbert Xu.
Signed-off-by: David S. Miller <davem@davemloft.net>
Pushing original fragments through causes several problems. For example
for matching, frags may not be matched correctly. Take following
example:
<example>
On HOSTA do:
ip6tables -I INPUT -p icmpv6 -j DROP
ip6tables -I INPUT -p icmpv6 -m icmp6 --icmpv6-type 128 -j ACCEPT
and on HOSTB you do:
ping6 HOSTA -s2000 (MTU is 1500)
Incoming echo requests will be filtered out on HOSTA. This issue does
not occur with smaller packets than MTU (where fragmentation does not happen)
</example>
As was discussed previously, the only correct solution seems to be to use
reassembled skb instead of separete frags. Doing this has positive side
effects in reducing sk_buff by one pointer (nfct_reasm) and also the reams
dances in ipvs and conntrack can be removed.
Future plan is to remove net/ipv6/netfilter/nf_conntrack_reasm.c
entirely and use code in net/ipv6/reassembly.c instead.
Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Marcelo Ricardo Leitner <mleitner@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use "@" to refer to parameters in the kernel-doc description. According
to Documentation/kernel-doc-nano-HOWTO.txt "&" shall be used to refer to
structures only.
Signed-off-by: Mathias Krause <mathias.krause@secunet.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This function has usage beside IPsec so move it to the core skbuff code.
While doing so, give it some documentation and change its return type to
'unsigned char *' to be in line with skb_put().
Signed-off-by: Mathias Krause <mathias.krause@secunet.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Sometimes we need to coalesce the rx frags to avoid frag list. One example is
virtio-net driver which tries to use small frags for both MTU sized packet and
GSO packet. So this patch introduce skb_coalesce_rx_frag() to do this.
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Michael Dalton <mwdalton@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, skb_checksum walks over 1) linearized, 2) frags[], and
3) frag_list data and calculats the one's complement, a 32 bit
result suitable for feeding into itself or csum_tcpudp_magic(),
but unsuitable for SCTP as we're calculating CRC32c there.
Hence, in order to not re-implement the very same function in
SCTP (and maybe other protocols) over and over again, use an
update() + combine() callback internally to allow for walking
over the skb with different algorithms.
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now ipv6_gso_segment() is stackable, its relatively easy to
implement GSO/TSO support for SIT tunnels
Performance results, when segmentation is done after tunnel
device (as no NIC is yet enabled for TSO SIT support) :
Before patch :
lpq84:~# ./netperf -H 2002:af6:1153:: -Cc
MIGRATED TCP STREAM TEST from ::0 (::) port 0 AF_INET6 to 2002:af6:1153:: () port 0 AF_INET6
Recv Send Send Utilization Service Demand
Socket Socket Message Elapsed Send Recv Send Recv
Size Size Size Time Throughput local remote local remote
bytes bytes bytes secs. 10^6bits/s % S % S us/KB us/KB
87380 16384 16384 10.00 3168.31 4.81 4.64 2.988 2.877
After patch :
lpq84:~# ./netperf -H 2002:af6:1153:: -Cc
MIGRATED TCP STREAM TEST from ::0 (::) port 0 AF_INET6 to 2002:af6:1153:: () port 0 AF_INET6
Recv Send Send Utilization Service Demand
Socket Socket Message Elapsed Send Recv Send Recv
Size Size Size Time Throughput local remote local remote
bytes bytes bytes secs. 10^6bits/s % S % S us/KB us/KB
87380 16384 16384 10.00 5525.00 7.76 5.17 2.763 1.840
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now inet_gso_segment() is stackable, its relatively easy to
implement GSO/TSO support for IPIP
Performance results, when segmentation is done after tunnel
device (as no NIC is yet enabled for TSO IPIP support) :
Before patch :
lpq83:~# ./netperf -H 7.7.9.84 -Cc
MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 7.7.9.84 () port 0 AF_INET
Recv Send Send Utilization Service Demand
Socket Socket Message Elapsed Send Recv Send Recv
Size Size Size Time Throughput local remote local remote
bytes bytes bytes secs. 10^6bits/s % S % S us/KB us/KB
87380 16384 16384 10.00 3357.88 5.09 3.70 2.983 2.167
After patch :
lpq83:~# ./netperf -H 7.7.9.84 -Cc
MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 7.7.9.84 () port 0 AF_INET
Recv Send Send Utilization Service Demand
Socket Socket Message Elapsed Send Recv Send Recv
Size Size Size Time Throughput local remote local remote
bytes bytes bytes secs. 10^6bits/s % S % S us/KB us/KB
87380 16384 16384 10.00 7710.19 4.52 6.62 1.152 1.687
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In order to support GSO on IPIP, we need to make
inet_gso_segment() stackable.
It should not assume network header starts right after mac
header.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
While working on virtio_net new allocation strategy to increase
payload/truesize ratio, we found that refactoring sk_page_frag_refill()
was needed.
This patch splits sk_page_frag_refill() into two parts, adding
skb_page_frag_refill() which can be used without a socket.
While we are at it, add a minimum frag size of 32 for
sk_page_frag_refill()
Michael will either use netdev_alloc_frag() from softirq context,
or skb_page_frag_refill() from process context in refill_work()
(GFP_KERNEL allocations)
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Michael Dalton <mwdalton@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
And thus we have only one function definition
Signed-off-by: Denis Kirjanov <kda@linux-powerpc.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/net/ethernet/emulex/benet/be.h
drivers/net/usb/qmi_wwan.c
drivers/net/wireless/brcm80211/brcmfmac/dhd_bus.h
include/net/netfilter/nf_conntrack_synproxy.h
include/net/secure_seq.h
The conflicts are of two varieties:
1) Conflicts with Joe Perches's 'extern' removal from header file
function declarations. Usually it's an argument signature change
or a function being added/removed. The resolutions are trivial.
2) Some overlapping changes in qmi_wwan.c and be.h, one commit adds
a new value, another changes an existing value. That sort of
thing.
Signed-off-by: David S. Miller <davem@davemloft.net>
Since commit c93bdd0e03 ("netvm: allow skb allocation to use PFMEMALLOC
reserves"), hole size is one bit less than what is written in the comment.
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
bnx2x makes a dangerous use of skb_is_gso_v6().
It should first make sure skb is a gso packet
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Eilon Greenstein <eilong@broadcom.com>
Acked-by: Dmitry Kravkov <dmitry@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There are a mix of function prototypes with and without extern
in the kernel sources. Standardize on not using extern for
function prototypes.
Function prototypes don't need to be written with extern.
extern is assumed by the compiler. Its use is as unnecessary as
using auto to declare automatic/local variables in a block.
Signed-off-by: Joe Perches <joe@perches.com>
This function was only used when a packet was sent to another netns. Now, it can
also be used after tunnel encapsulation or decapsulation.
Only skb_orphan() should not be done when a packet is not crossing netns.
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The name of the function in the comment is __skb_alloc_page() while we
are actually commenting __skb_alloc_pages(). Fix this typo and make it
a valid kernel doc comment.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
To let it be reused and reduce code duplication. Also document this function.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Eliezer renames several *ll_poll to *busy_poll, but forgets
CONFIG_NET_LL_RX_POLL, so in case of confusion, rename it too.
Cc: Eliezer Tamir <eliezer.tamir@linux.intel.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
David suggested to add a BUG_ON() to catch if some layer
sets skb->sk pointer without a corresponding destructor.
As skb can sit in a queue, it's mandatory to make sure the
socket cannot disappear, and it's usually done by taking a
reference on the socket, then releasing it from the skb
destructor.
This patch is a follow-up to commit c34a761231
("net: skb_orphan() changes") and will be reverted after
catching all possible offenders if any.
Suggested-by: David Miller <davem@davemloft.net>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It is illegal to set skb->sk without corresponding destructor.
Its therefore safe for skb_orphan() to not clear skb->sk if
skb->destructor is not set.
Also avoid clearing skb->destructor if already NULL.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/net/ethernet/freescale/fec_main.c
drivers/net/ethernet/renesas/sh_eth.c
net/ipv4/gre.c
The GRE conflict is between a bug fix (kfree_skb --> kfree_skb_list)
and the splitting of the gre.c code into seperate files.
The FEC conflict was two sets of changes adding ethtool support code
in an "!CONFIG_M5272" CPP protected block.
Finally the sh_eth.c conflict was between one commit add bits set
in the .eesr_err_check mask whilst another commit removed the
.tx_error_check member and assignments.
Signed-off-by: David S. Miller <davem@davemloft.net>
The goal of this new function is to perform all needed cleanup before sending
an skb into another netns.
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
commit 68c3316311 ("v4 GRE: Add TCP segmentation offload for GRE")
added a possible skb leak, because it frees only the head of segment
list, in case a skb_linearize() call fails.
This patch adds a kfree_skb_list() helper to fix the bug.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Pravin B Shelar <pshelar@nicira.com>
Cc: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Similar to the following commits:
commit 00f97da17a (netpoll: fix position of network header)
commit 525cebedb3 (pktgen: Fix position of ip and udp header)
using skb_tail_offset() seems not correct since the offset
is based on head pointer.
With the last caller removed, skb_tail_offset() can be killed
finally.
Cc: Thomas Graf <tgraf@suug.ch>
Cc: Daniel Borkmann <dborkmann@redhat.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Adds an ndo_ll_poll method and the code that supports it.
This method can be used by low latency applications to busy-poll
Ethernet device queues directly from the socket code.
sysctl_net_ll_poll controls how many microseconds to poll.
Default is zero (disabled).
Individual protocol support will be added by subsequent patches.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Tested-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Merge 'net' bug fixes into 'net-next' as we have patches
that will build on top of them.
This merge commit includes a change from Emil Goode
(emilgoode@gmail.com) that fixes a warning that would
have been introduced by this merge. Specifically it
fixes the pingv6_ops method ipv6_chk_addr() to add a
"const" to the "struct net_device *dev" argument and
likewise update the dummy_ipv6_chk_addr() declaration.
Signed-off-by: David S. Miller <davem@davemloft.net>
udp6 over GRE tunnel does not work after to GRE tso changes. GRE
tso handler passes inner packet but keeps track of outer header
start in SKB_GSO_CB(skb)->mac_offset. udp6 fragment need to
take care of outer header, which start at the mac_offset, while
adding fragment header.
This bug is introduced by commit 68c3316311 (GRE: Add TCP
segmentation offload for GRE).
Reported-by: Dmitry Kravkov <dkravkov@gmail.com>
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Tested-by: Dmitry Kravkov <dmitry@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
commit 1a37e412a0 (net: Use 16bits for *_headers
fields of struct skbuff) converts skb->*_header to u16,
some #if NET_SKBUFF_DATA_USES_OFFSET are now useless,
and to be safe, we could just use "X = (typeof(X)) ~0U;"
as suggested by David.
Cc: David S. Miller <davem@davemloft.net>
Cc: Simon Horman <horms@verge.net.au>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This corrects an regression introduced by "net: Use 16bits for *_headers
fields of struct skbuff" when NET_SKBUFF_DATA_USES_OFFSET is not set. In
that case skb->tail will be a pointer however skb->network_header is now
an offset.
This patch corrects the problem by adding a wrapper to return skb tail as
an offset regardless of the value of NET_SKBUFF_DATA_USES_OFFSET. It seems
that skb->tail that this offset may be more than 64k and some care has been
taken to treat such cases as an error.
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>