At first Jakub Zawadzki noticed that some divisions by reciprocal_divide
were not correct. (off by one in some cases)
http://www.wireshark.org/~darkjames/reciprocal-buggy.c
He could also show this with BPF:
http://www.wireshark.org/~darkjames/set-and-dump-filter-k-bug.c
The reciprocal divide in linux kernel is not generic enough,
lets remove its use in BPF, as it is not worth the pain with
current cpus.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Jakub Zawadzki <darkjames-ws@darkjames.pl>
Cc: Mircea Gherzan <mgherzan@gmail.com>
Cc: Daniel Borkmann <dxchgb@gmail.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Matt Evans <matt@ozlabs.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use <asm/opcodes.h> to correctly transform instruction byte ordering
into in-memory ordering.
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Follow-up on module_free()/vfree() that takes care of the rest, so no
longer this workaround with work_struct needed.
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Mircea Gherzan <mgherzan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If bpf_jit_enable > 1, then we dump the emitted JIT compiled image
after creation. Currently, only SPARC and PowerPC has similar output
as in the reference implementation on x86_64. Make a small helper
function in order to reduce duplicated code and make the dump output
uniform across architectures x86_64, SPARC, PPC, ARM (e.g. on ARM
flen, pass and proglen are currently not shown, but would be
interesting to know as well), also for future BPF JIT implementations
on other archs.
Cc: Mircea Gherzan <mgherzan@gmail.com>
Cc: Matt Evans <matt@ozlabs.org>
Cc: Eric Dumazet <eric.dumazet@google.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
k is u32 which never < 0, need type cast, or cause issue.
Signed-off-by: Chen Gang <gang.chen@asianux.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Mircea Gherzan <mgherzan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The original code was generating an lsl instructions using the value
of ARM_R8 (skb_headlen, possibly uninitialized if no skb_headlen
access was required) as a shift amount.
Signed-off-by: Nicolas Schichan <nschichan@freebox.fr>
Acked-by: Mircea Gherzan <mgherzan@gmail.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull networking changes from David Miller:
1) Allow to dump, monitor, and change the bridge multicast database
using netlink. From Cong Wang.
2) RFC 5961 TCP blind data injection attack mitigation, from Eric
Dumazet.
3) Networking user namespace support from Eric W. Biederman.
4) tuntap/virtio-net multiqueue support by Jason Wang.
5) Support for checksum offload of encapsulated packets (basically,
tunneled traffic can still be checksummed by HW). From Joseph
Gasparakis.
6) Allow BPF filter access to VLAN tags, from Eric Dumazet and
Daniel Borkmann.
7) Bridge port parameters over netlink and BPDU blocking support
from Stephen Hemminger.
8) Improve data access patterns during inet socket demux by rearranging
socket layout, from Eric Dumazet.
9) TIPC protocol updates and cleanups from Ying Xue, Paul Gortmaker, and
Jon Maloy.
10) Update TCP socket hash sizing to be more in line with current day
realities. The existing heurstics were choosen a decade ago.
From Eric Dumazet.
11) Fix races, queue bloat, and excessive wakeups in ATM and
associated drivers, from Krzysztof Mazur and David Woodhouse.
12) Support DOVE (Distributed Overlay Virtual Ethernet) extensions
in VXLAN driver, from David Stevens.
13) Add "oops_only" mode to netconsole, from Amerigo Wang.
14) Support set and query of VEB/VEPA bridge mode via PF_BRIDGE, also
allow DCB netlink to work on namespaces other than the initial
namespace. From John Fastabend.
15) Support PTP in the Tigon3 driver, from Matt Carlson.
16) tun/vhost zero copy fixes and improvements, plus turn it on
by default, from Michael S. Tsirkin.
17) Support per-association statistics in SCTP, from Michele
Baldessari.
And many, many, driver updates, cleanups, and improvements. Too
numerous to mention individually.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1722 commits)
net/mlx4_en: Add support for destination MAC in steering rules
net/mlx4_en: Use generic etherdevice.h functions.
net: ethtool: Add destination MAC address to flow steering API
bridge: add support of adding and deleting mdb entries
bridge: notify mdb changes via netlink
ndisc: Unexport ndisc_{build,send}_skb().
uapi: add missing netconf.h to export list
pkt_sched: avoid requeues if possible
solos-pci: fix double-free of TX skb in DMA mode
bnx2: Fix accidental reversions.
bna: Driver Version Updated to 3.1.2.1
bna: Firmware update
bna: Add RX State
bna: Rx Page Based Allocation
bna: TX Intr Coalescing Fix
bna: Tx and Rx Optimizations
bna: Code Cleanup and Enhancements
ath9k: check pdata variable before dereferencing it
ath5k: RX timestamp is reported at end of frame
ath9k_htc: RX timestamp is reported at end of frame
...
The offset must be multiplied by 4 to be sure to access the correct
32bit word in the stack scratch space.
For instance, a store at scratch memory cell #1 was generating the
following:
st r4, [sp, #1]
While the correct code for this is:
st r4, [sp, #4]
To reproduce the bug (assuming your system has a NIC with the mac
address 52:54:00:12:34:56):
echo 0 > /proc/sys/net/core/bpf_jit_enable
tcpdump -ni eth0 "ether[1] + ether[2] - ether[3] * ether[4] - ether[5] \
== -0x3AA" # this will capture packets as expected
echo 1 > /proc/sys/net/core/bpf_jit_enable
tcpdump -ni eth0 "ether[1] + ether[2] - ether[3] * ether[4] - ether[5] \
== -0x3AA" # this will not.
This bug was present since the original inclusion of bpf_jit for ARM
(ddecdfce: ARM: 7259/3: net: JIT compiler for packet filters).
Signed-off-by: Nicolas Schichan <nschichan@freebox.fr>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Official prototype for kzalloc is:
void *kzalloc(size_t, gfp_t);
The ARM bpf_jit code was having the assumption that it was:
void *kzalloc(gfp_t, size);
This was resulting the use of some random GFP flags depending on the
size requested and some random overflows once the really needed size
was more than the value of GFP_KERNEL.
This bug was present since the original inclusion of bpf_jit for ARM
(ddecdfce: ARM: 7259/3: net: JIT compiler for packet filters).
Signed-off-by: Nicolas Schichan <nschichan@freebox.fr>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch is a follow-up for patch "net: filter: add vlan tag access"
to support the new VLAN_TAG/VLAN_TAG_PRESENT accessors in BPF JIT.
Signed-off-by: Daniel Borkmann <daniel.borkmann@tik.ee.ethz.ch>
Cc: Mircea Gherzan <mgherzan@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: Mircea Gherzan <mgherzan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch is a follow-up for patch "filter: add XOR instruction for use
with X/K" that implements BPF ARM JIT parts for the BPF XOR operation.
Signed-off-by: Daniel Borkmann <daniel.borkmann@tik.ee.ethz.ch>
Cc: Mircea Gherzan <mgherzan@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: Mircea Gherzan <mgherzan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
JIT support for the XOR operation introduced by the commit
ffe06c17af.
Signed-off-by: Mircea Gherzan <mgherzan@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Based of Matt Evans's PPC64 implementation.
The compiler generates ARM instructions but interworking is
supported for Thumb2 kernels.
Supports both little and big endian. Unaligned loads are emitted
for ARMv6+. Not all the BPF opcodes that deal with ancillary data
are supported. The scratch memory of the filter lives on the stack.
Hardware integer division is used if it is available.
Enabled in the same way as for x86-64 and PPC64:
echo 1 > /proc/sys/net/core/bpf_jit_enable
A value greater than 1 enables opcode output.
Signed-off-by: Mircea Gherzan <mgherzan@gmail.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Eric Dumazet