Commit Graph

106 Commits

Author SHA1 Message Date
Ian Kumlien d0af683407 flow_dissector: Update pptp handling to avoid null pointer deref.
__skb_flow_dissect can be called with a skb or a data packet, either
can be NULL. All calls seems to have been moved to __skb_header_pointer
except the pptp handling which is still calling skb_header_pointer.

skb_header_pointer will use skb->data and thus:
[  109.556866] BUG: unable to handle kernel NULL pointer dereference at 0000000000000080
[  109.557102] IP: [<ffffffff88dc02f8>] __skb_flow_dissect+0xa88/0xce0
[  109.557263] PGD 0
[  109.557338]
[  109.557484] Oops: 0000 [#1] SMP
[  109.557562] Modules linked in: chaoskey
[  109.557783] CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.9.0 #79
[  109.557867] Hardware name: Supermicro A1SRM-LN7F/LN5F/A1SRM-LN7F-2758, BIOS 1.0c 11/04/2015
[  109.557957] task: ffff94085c27bc00 task.stack: ffffb745c0068000
[  109.558041] RIP: 0010:[<ffffffff88dc02f8>]  [<ffffffff88dc02f8>] __skb_flow_dissect+0xa88/0xce0
[  109.558203] RSP: 0018:ffff94087fc83d40  EFLAGS: 00010206
[  109.558286] RAX: 0000000000000130 RBX: ffffffff8975bf80 RCX: ffff94084fab6800
[  109.558373] RDX: 0000000000000010 RSI: 000000000000000c RDI: 0000000000000000
[  109.558460] RBP: 0000000000000b88 R08: 0000000000000000 R09: 0000000000000022
[  109.558547] R10: 0000000000000008 R11: ffff94087fc83e04 R12: 0000000000000000
[  109.558763] R13: ffff94084fab6800 R14: ffff94087fc83e04 R15: 000000000000002f
[  109.558979] FS:  0000000000000000(0000) GS:ffff94087fc80000(0000) knlGS:0000000000000000
[  109.559326] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  109.559539] CR2: 0000000000000080 CR3: 0000000281809000 CR4: 00000000001026e0
[  109.559753] Stack:
[  109.559957]  000000000000000c ffff94084fab6822 0000000000000001 ffff94085c2b5fc0
[  109.560578]  0000000000000001 0000000000002000 0000000000000000 0000000000000000
[  109.561200]  0000000000000000 0000000000000000 0000000000000000 0000000000000000
[  109.561820] Call Trace:
[  109.562027]  <IRQ>
[  109.562108]  [<ffffffff88dfb4fa>] ? eth_get_headlen+0x7a/0xf0
[  109.562522]  [<ffffffff88c5a35a>] ? igb_poll+0x96a/0xe80
[  109.562737]  [<ffffffff88dc912b>] ? net_rx_action+0x20b/0x350
[  109.562953]  [<ffffffff88546d68>] ? __do_softirq+0xe8/0x280
[  109.563169]  [<ffffffff8854704a>] ? irq_exit+0xaa/0xb0
[  109.563382]  [<ffffffff8847229b>] ? do_IRQ+0x4b/0xc0
[  109.563597]  [<ffffffff8902d4ff>] ? common_interrupt+0x7f/0x7f
[  109.563810]  <EOI>
[  109.563890]  [<ffffffff88d57530>] ? cpuidle_enter_state+0x130/0x2c0
[  109.564304]  [<ffffffff88d57520>] ? cpuidle_enter_state+0x120/0x2c0
[  109.564520]  [<ffffffff8857eacf>] ? cpu_startup_entry+0x19f/0x1f0
[  109.564737]  [<ffffffff8848d55a>] ? start_secondary+0x12a/0x140
[  109.564950] Code: 83 e2 20 a8 80 0f 84 60 01 00 00 c7 04 24 08 00
00 00 66 85 d2 0f 84 be fe ff ff e9 69 fe ff ff 8b 34 24 89 f2 83 c2
04 66 85 c0 <41> 8b 84 24 80 00 00 00 0f 49 d6 41 8d 31 01 d6 41 2b 84
24 84
[  109.569959] RIP  [<ffffffff88dc02f8>] __skb_flow_dissect+0xa88/0xce0
[  109.570245]  RSP <ffff94087fc83d40>
[  109.570453] CR2: 0000000000000080

Fixes: ab10dccb11 ("rps: Inspect PPTP encapsulated by GRE to get flow hash")
Signed-off-by: Ian Kumlien <ian.kumlien@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-02 12:53:34 -05:00
Simon Horman 972d3876fa flow dissector: ICMP support
Allow dissection of ICMP(V6) type and code. This should only occur
if a packet is ICMP(V6) and the dissector has FLOW_DISSECTOR_KEY_ICMP set.

There are currently no users of FLOW_DISSECTOR_KEY_ICMP.
A follow-up patch will allow FLOW_DISSECTOR_KEY_ICMP to be used by
the flower classifier.

Signed-off-by: Simon Horman <simon.horman@netronome.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-08 11:45:21 -05:00
David S. Miller 0b42f25d2f Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
udplite conflict is resolved by taking what 'net-next' did
which removed the backlog receive method assignment, since
it is no longer necessary.

Two entries were added to the non-priv ethtool operations
switch statement, one in 'net' and one in 'net-next, so
simple overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-26 23:42:21 -05:00
Eric Dumazet c9b8af1330 flow_dissect: call init_default_flow_dissectors() earlier
Andre Noll reported panics after my recent fix (commit 34fad54c25
"net: __skb_flow_dissect() must cap its return value")

After some more headaches, Alexander root caused the problem to
init_default_flow_dissectors() being called too late, in case
a network driver like IGB is not a module and receives DHCP message
very early.

Fix is to call init_default_flow_dissectors() much earlier,
as it is a core infrastructure and does not depend on another
kernel service.

Fixes: 06635a35d1 ("flow_dissect: use programable dissector in skb_flow_dissect and friends")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Andre Noll <maan@tuebingen.mpg.de>
Diagnosed-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-22 14:44:01 -05:00
David S. Miller bb598c1b8c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Several cases of bug fixes in 'net' overlapping other changes in
'net-next-.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-15 10:54:36 -05:00
Eric Dumazet 34fad54c25 net: __skb_flow_dissect() must cap its return value
After Tom patch, thoff field could point past the end of the buffer,
this could fool some callers.

If an skb was provided, skb->len should be the upper limit.
If not, hlen is supposed to be the upper limit.

Fixes: a6e544b0a8 ("flow_dissector: Jump to exit code in __skb_flow_dissect")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Yibin Yang <yibyang@cisco.com
Acked-by: Alexander Duyck <alexander.h.duyck@intel.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-12 23:41:53 -05:00
David S. Miller 27058af401 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Mostly simple overlapping changes.

For example, David Ahern's adjacency list revamp in 'net-next'
conflicted with an adjacency list traversal bug fix in 'net'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-30 12:42:58 -04:00
Florian Westphal b917783c7b flow_dissector: __skb_get_hash_symmetric arg can be const
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-29 15:10:21 -04:00
Arnd Bergmann bc72f3dd89 flow_dissector: fix vlan tag handling
gcc warns about an uninitialized pointer dereference in the vlan
priority handling:

net/core/flow_dissector.c: In function '__skb_flow_dissect':
net/core/flow_dissector.c:281:61: error: 'vlan' may be used uninitialized in this function [-Werror=maybe-uninitialized]

As pointed out by Jiri Pirko, the variable is never actually used
without being initialized first as the only way it end up uninitialized
is with skb_vlan_tag_present(skb)==true, and that means it does not
get accessed.

However, the warning hints at some related issues that I'm addressing
here:

- the second check for the vlan tag is different from the first one
  that tests the skb for being NULL first, causing both the warning
  and a possible NULL pointer dereference that was not entirely fixed.
- The same patch that introduced the NULL pointer check dropped an
  earlier optimization that skipped the repeated check of the
  protocol type
- The local '_vlan' variable is referenced through the 'vlan' pointer
  but the variable has gone out of scope by the time that it is
  accessed, causing undefined behavior

Caching the result of the 'skb && skb_vlan_tag_present(skb)' check
in a local variable allows the compiler to further optimize the
later check. With those changes, the warning also disappears.

Fixes: 3805a938a6 ("flow_dissector: Check skb for VLAN only if skb specified.")
Fixes: d5709f7ab7 ("flow_dissector: For stripped vlan, get vlan info from skb->vlan_tci")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Eric Garver <e@erig.me>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-27 16:36:03 -04:00
Eric Garver 3805a938a6 flow_dissector: Check skb for VLAN only if skb specified.
Fixes a panic when calling eth_get_headlen(). Noticed on i40e driver.

Fixes: d5709f7ab7 ("flow_dissector: For stripped vlan, get vlan info from skb->vlan_tci")
Signed-off-by: Eric Garver <e@erig.me>
Reviewed-by: Jakub Sitnicki <jkbs@redhat.com>
Acked-by: Amir Vadai <amir@vadai.me>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-19 10:35:46 -04:00
David S. Miller b20b378d49 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/mediatek/mtk_eth_soc.c
	drivers/net/ethernet/qlogic/qed/qed_dcbx.c
	drivers/net/phy/Kconfig

All conflicts were cases of overlapping commits.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-12 15:52:44 -07:00
Gao Feng 635c223cfa rps: flow_dissector: Fix uninitialized flow_keys used in __skb_get_hash possibly
The original codes depend on that the function parameters are evaluated from
left to right. But the parameter's evaluation order is not defined in C
standard actually.

When flow_keys_have_l4(&keys) is invoked before ___skb_get_hash(skb, &keys,
hashrnd) with some compilers or environment, the keys passed to
flow_keys_have_l4 is not initialized.

Fixes: 6db61d79c1 ("flow_dissector: Ignore flow dissector return value from ___skb_get_hash")

Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-01 22:45:03 -07:00
Hadar Hen Zion f6a6692769 flow_dissector: Get vlan priority in addition to vlan id
Add vlan priority check to the flow dissector by adding new flow
dissector struct, flow_dissector_key_vlan which includes vlan tag
fields.

vlan_id and flow_label fields were under the same struct
(flow_dissector_key_tags). It was a convenient setting since struct
flow_dissector_key_tags is used by struct flow_keys and by setting
vlan_id and flow_label under the same struct, we get precisely 24 or 48
bytes in flow_keys from flow_dissector_key_basic.

Now, when adding vlan priority support, the code will be cleaner if
flow_label and vlan tag won't be under the same struct anymore.

Signed-off-by: Hadar Hen Zion <hadarh@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-18 23:13:13 -07:00
Hadar Hen Zion d5709f7ab7 flow_dissector: For stripped vlan, get vlan info from skb->vlan_tci
Early in the datapath skb_vlan_untag function is called, stripped
the vlan from the skb and set skb->vlan_tci and skb->vlan_proto fields.

The current dissection doesn't handle stripped vlan packets correctly.
In some flows, vlan doesn't exist in skb->data anymore when applying
flow dissection on the skb, fix that.

In case vlan info wasn't stripped before applying flow_dissector (RPS
flow for example), or in case of skb with multiple vlans (e.g. 802.1ad),
get the vlan info from skb->data. The flow_dissector correctly skips
any number of vlans and stores only the first level vlan.

Fixes: 0744dd00c1 ('net: introduce skb_flow_dissect()')
Signed-off-by: Hadar Hen Zion <hadarh@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-18 23:13:13 -07:00
Gao Feng ab10dccb11 rps: Inspect PPTP encapsulated by GRE to get flow hash
The PPTP is encapsulated by GRE header with that GRE_VERSION bits
must contain one. But current GRE RPS needs the GRE_VERSION must be
zero. So RPS does not work for PPTP traffic.

In my test environment, there are four MIPS cores, and all traffic
are passed through by PPTP. As a result, only one core is 100% busy
while other three cores are very idle. After this patch, the usage
of four cores are balanced well.

Signed-off-by: Gao Feng <fgao@ikuai8.com>
Reviewed-by: Philip Prindeville <philipp@redfish-solutions.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-10 17:22:14 -07:00
David S. Miller eb70db8756 packet: Use symmetric hash for PACKET_FANOUT_HASH.
People who use PACKET_FANOUT_HASH want a symmetric hash, meaning that
they want packets going in both directions on a flow to hash to the
same bucket.

The core kernel SKB hash became non-symmetric when the ipv6 flow label
and other entities were incorporated into the standard flow hash order
to increase entropy.

But there are no users of PACKET_FANOUT_HASH who want an assymetric
hash, they all want a symmetric one.

Therefore, use the flow dissector to compute a flat symmetric hash
over only the protocol, addresses and ports.  This hash does not get
installed into and override the normal skb hash, so this change has
no effect whatsoever on the rest of the stack.

Reported-by: Eric Leblond <eric@regit.org>
Tested-by: Eric Leblond <eric@regit.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-01 16:07:50 -04:00
Amir Vadai 8de2d793da net/flow_dissector: Make dissector_uses_key() and skb_flow_dissector_target() public
Will be used in a following patch to query if a key is being used, and
what it's value in the target object.

Acked-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Amir Vadai <amir@vadai.me>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-10 16:24:02 -05:00
Alexander Duyck b3c3106ce3 flow_dissector: Use same pointer for IPv4 and IPv6 addresses
The IPv6 parsing was using a local pointer when it could use the same
pointer as the IPv4 portion of the code since the key_addrs can support
both IPv4 and IPv6 as it is just a pointer.

Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Acked-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-24 13:58:05 -05:00
Alexander Duyck 224516b3a7 flow_dissector: Correctly handle parsing FCoE
The flow dissector bits handling FCoE didn't bother to actually validate
that the space there was enough for the FCoE header.  So we need to update
things so that if there is room we add the header and report a good result,
otherwise we do not add the header, and report the bad result.

Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Acked-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-24 13:58:04 -05:00
Alexander Duyck 43d2ccb3c1 flow_dissector: Fix fragment handling for header length computation
It turns out that for IPv4 we were reporting the ip_proto of the fragment,
and for IPv6 we were not.  This patch updates that behavior so that we
always report the IP protocol of the fragment.  In addition it takes the
steps of updating the payload offset code so that we will determine the
start of the payload not including the L4 header for any fragment after the
first.

Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Acked-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-24 13:58:04 -05:00
Alexander Duyck 918c023f29 flow_dissector: Check for IP fragmentation even if not using IPv4 address
This patch corrects the logic for the IPv4 parsing so that it is consistent
with how we handle IPv6.  Specifically if we do not have the flow key
indicating we want the addresses we still may need to take a look at the IP
fragmentation bits and to see if we should stop after we have recognized
the L3 header.

Fixes: 807e165dc4 ("flow_dissector: Add control/reporting of fragmentation")
Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Acked-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-24 13:58:04 -05:00
Alexander Duyck 78565208d7 net: Copy inner L3 and L4 headers as unaligned on GRE TEB
This patch corrects the unaligned accesses seen on GRE TEB tunnels when
generating hash keys.  Specifically what this patch does is make it so that
we force the use of skb_copy_bits when the GRE inner headers will be
unaligned due to NET_IP_ALIGNED being a non-zero value.

Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Acked-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-16 15:25:01 -05:00
Alexander Duyck 461547f315 flow_dissector: Fix unaligned access in __skb_flow_dissector when used by eth_get_headlen
This patch fixes an issue with unaligned accesses when using
eth_get_headlen on a page that was DMA aligned instead of being IP aligned.
The fact is when trying to check the length we don't need to be looking at
the flow label so we can reorder the checks to first check if we are
supposed to gather the flow label and then make the call to actually get
it.

v2:  Updated path so that either STOP_AT_FLOW_LABEL or KEY_FLOW_LABEL can
     cause us to check for the flow label.

Reported-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-09 07:07:48 -05:00
David S. Miller 20a17bf6c0 flow_dissector: Use 'const' where possible.
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-01 21:19:17 -07:00
David S. Miller a17ace95b0 flow: Move __get_hash_from_flowi{4,6} into flow_dissector.c
These cannot live in net/core/flow.c which only builds when XFRM is
enabled.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-01 17:00:24 -07:00
David S. Miller 4b36993d3d flow_dissector: Don't use bit fields.
Just have a flags member instead.

   In file included from include/linux/linkage.h:4:0,
                    from include/linux/kernel.h:6,
                    from net/core/flow_dissector.c:1:
   In function 'flow_keys_hash_start',
       inlined from 'flow_hash_from_keys' at net/core/flow_dissector.c:553:34:
>> include/linux/compiler.h:447:38: error: call to '__compiletime_assert_459' declared with attribute error: BUILD_BUG_ON failed: FLOW_KEYS_HASH_OFFSET % sizeof(u32)

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-01 16:46:08 -07:00
Tom Herbert 6db61d79c1 flow_dissector: Ignore flow dissector return value from ___skb_get_hash
In ___skb_get_hash ignore return value from skb_flow_dissect_flow_keys.
A failure in that function likely means that there was a parse error,
so we may as well use whatever fields were found before the error was
hit.  This is also good because it means we won't keep trying to derive
the hash on subsequent calls to skb_get_hash for the same packet.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-01 15:06:23 -07:00
Tom Herbert 823b969395 flow_dissector: Add control/reporting of encapsulation
Add an input flag to flow dissector on rather dissection should stop
when encapsulation is detected (IP/IP or GRE). Also, add a key_control
flag that indicates encapsulation was encountered during the
dissection.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-01 15:06:23 -07:00
Tom Herbert 872b1abb1e flow_dissector: Add flag to stop parsing when an IPv6 flow label is seen
Add an input flag to flow dissector on rather dissection should be
stopped when a flow label is encountered. Presumably, the flow label
is derived from a sufficient hash of an inner transport packet so
further dissection is not needed (that is ports are not included in
the flow hash). Using the flow label instead of ports has the additional
benefit that packet fragments should hash to same value as non-fragments
for a flow (assuming that the same flow label is used).

We set this flag by default in for skb_get_hash.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-01 15:06:23 -07:00
Tom Herbert 8306b688f1 flow_dissector: Add flag to stop parsing at L3
Add an input flag to flow dissector on rather dissection should be
stopped when an L3 packet is encountered. This would be useful if a
caller just wanted to get IP addresses of the outermost header (e.g.
to do an L3 hash).

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-01 15:06:23 -07:00
Tom Herbert b840f28b90 flow_dissector: Support IPv6 fragment header
Parse NEXTHDR_FRAGMENT. When seen account for it in the fragment bits of
key_control. Also, check if first fragment should be parsed.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-01 15:06:22 -07:00
Tom Herbert 807e165dc4 flow_dissector: Add control/reporting of fragmentation
Add an input flag to flow dissector on rather dissection should be
attempted on a first fragment. Also add key_control flags to indicate
that a packet is a fragment or first fragment.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-01 15:06:22 -07:00
Tom Herbert cd79a2382a flow_dissector: Add flags argument to skb_flow_dissector functions
The flags argument will allow control of the dissection process (for
instance whether to parse beyond L3).

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-01 15:06:22 -07:00
Tom Herbert a6e544b0a8 flow_dissector: Jump to exit code in __skb_flow_dissect
Instead of returning immediately (on a parsing failure for instance) we
jump to cleanup code. This always sets protocol values in key_control
(even on a failure there is still valid information in the key_tags that
was set before the problem was hit).

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-01 15:06:22 -07:00
Tom Herbert bcc83839ff skbuff: Make __skb_set_sw_hash a general function
Move __skb_set_sw_hash to skbuff.h and add __skb_set_hash which is
a common method (between __skb_set_sw_hash and skb_set_hash) to set
the hash in an skbuff.

Also, move skb_clear_hash to be closer to __skb_set_hash.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-01 15:06:22 -07:00
Tom Herbert f70ea018da net: Add functions to get skb->hash based on flow structures
Add skb_get_hash_flowi6 and skb_get_hash_flowi4 which derive an sk_buff
hash from flowi6 and flowi4 structures respectively. These functions
can be called when creating a packet in the output path where the new
sk_buff does not yet contain a fully formed packet that is parsable by
flow dissector.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-31 17:07:11 -07:00
Geert Uytterhoeven 8e690ffdbc flow_dissector: Pre-initialize ip_proto in __skb_flow_dissect()
net/core/flow_dissector.c: In function ‘__skb_flow_dissect’:
net/core/flow_dissector.c:132: warning: ‘ip_proto’ may be used uninitialized in this function

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-28 16:53:54 -07:00
Eric Dumazet 1e98a0f08a flow_dissector: fix ipv6 dst, hop-by-hop and routing ext hdrs
__skb_header_pointer() returns a pointer that must be checked.

Fixes infinite loop reported by Alexei, and add __must_check to
catch these errors earlier.

Fixes: 6a74fcf426 ("flow_dissector: add support for dst, hop-by-hop and routing ext hdrs")
Reported-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Tested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-12 21:58:49 -07:00
Tom Herbert 6a74fcf426 flow_dissector: add support for dst, hop-by-hop and routing ext hdrs
If dst, hop-by-hop or routing extension headers are present determine
length of the options and skip over them in flow dissection.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-12 14:24:28 -07:00
Tom Herbert 611d23c559 flow_dissector: Fix MPLS entropy label handling in flow dissector
Need to shift after masking to get label value for comparison.

Fixes: b3baa0fbd0 ("mpls: Add MPLS entropy label in flow_keys")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-12 14:24:27 -07:00
Tom Herbert b3baa0fbd0 mpls: Add MPLS entropy label in flow_keys
In flow dissector if an MPLS header contains an entropy label this is
saved in the new keyid field of flow_keys. The entropy label is
then represented in the flow hash function input.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-04 15:44:31 -07:00
Tom Herbert 1fdd512c92 net: Add GRE keyid in flow_keys
In flow dissector if a GRE header contains a keyid this is saved in the
new keyid field of flow_keys. The GRE keyid is then represented
in the flow hash function input.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-04 15:44:31 -07:00
Tom Herbert 87ee9e52ff net: Add IPv6 flow label to flow_keys
In flow_dissector set the flow label in flow_keys for IPv6. This also
removes the shortcircuiting of flow dissection when a non-zero label
is present, the flow label can be considered to provide additional
entropy for a hash.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-04 15:44:31 -07:00
Tom Herbert d34af823ff net: Add VLAN ID to flow_keys
In flow_dissector set vlan_id in flow_keys when VLAN is found.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-04 15:44:31 -07:00
Tom Herbert 45b47fd00c net: Get rid of IPv6 hash addresses flow keys
We don't need to return the IPv6 address hash as part of flow keys.
In general, using the IPv6 address hash is risky in a hash value
since the underlying use of xor provides no entropy. If someone
really needs the hash value they can get it from the full IPv6
addresses in flow keys (e.g. from flow_get_u32_src).

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-04 15:44:31 -07:00
Tom Herbert 9f24908901 net: Add keys for TIPC address
Add a new flow key for TIPC addresses.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-04 15:44:31 -07:00
Tom Herbert c3f8324188 net: Add full IPv6 addresses to flow_keys
This patch adds full IPv6 addresses into flow_keys and uses them as
input to the flow hash function. The implementation supports either
IPv4 or IPv6 addresses in a union, and selector is used to determine
how may words to input to jhash2.

We also add flow_get_u32_dst and flow_get_u32_src functions which are
used to get a u32 representation of the source and destination
addresses. For IPv6, ipv6_addr_hash is called. These functions retain
getting the legacy values of src and dst in flow_keys.

With this patch, Ethertype and IP protocol are now included in the
flow hash input.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-04 15:44:30 -07:00
Tom Herbert 42aecaa9bb net: Get skb hash over flow_keys structure
This patch changes flow hashing to use jhash2 over the flow_keys
structure instead just doing jhash_3words over src, dst, and ports.
This method will allow us take more input into the hashing function
so that we can include full IPv6 addresses, VLAN, flow labels etc.
without needing to resort to xor'ing which makes for a poor hash.

Acked-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-04 15:44:30 -07:00
Tom Herbert c468efe2c7 net: Remove superfluous setting of key_basic
key_basic is set twice in __skb_flow_dissect which seems unnecessary.
Remove second one.

Acked-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-04 15:44:30 -07:00
Tom Herbert ce3b535547 net: Simplify GRE case in flow_dissector
Do break when we see routing flag or a non-zero version number in GRE
header.

Acked-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-04 15:44:30 -07:00