The goal is to let the user follow an interface that moves to another
netns.

CC: Jiri Benc <jbenc@redhat.com>
CC: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Reviewed-by: NJiri Benc <jbenc@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The user should be able to follow any interface that moves to another
netns.  There is no reason to hide physical interfaces.

CC: Jiri Benc <jbenc@redhat.com>
CC: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Reviewed-by: NJiri Benc <jbenc@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

- Backwards Compatibility:
  If userspace wants to determine whether RTM_DELLINK supports the
  IFLA_IF_NETNSID property they should first send an RTM_GETLINK request
  with IFLA_IF_NETNSID on lo. If either EACCESS is returned or the reply
  does not include IFLA_IF_NETNSID userspace should assume that
  IFLA_IF_NETNSID is not supported on this kernel.
  If the reply does contain an IFLA_IF_NETNSID property userspace
  can send an RTM_DELLINK with a IFLA_IF_NETNSID property. If they receive
  EOPNOTSUPP then the kernel does not support the IFLA_IF_NETNSID property
  with RTM_DELLINK. Userpace should then fallback to other means.

- Security:
  Callers must have CAP_NET_ADMIN in the owning user namespace of the
  target network namespace.
Signed-off-by: NChristian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

- Backwards Compatibility:
  If userspace wants to determine whether RTM_SETLINK supports the
  IFLA_IF_NETNSID property they should first send an RTM_GETLINK request
  with IFLA_IF_NETNSID on lo. If either EACCESS is returned or the reply
  does not include IFLA_IF_NETNSID userspace should assume that
  IFLA_IF_NETNSID is not supported on this kernel.
  If the reply does contain an IFLA_IF_NETNSID property userspace
  can send an RTM_SETLINK with a IFLA_IF_NETNSID property. If they receive
  EOPNOTSUPP then the kernel does not support the IFLA_IF_NETNSID property
  with RTM_SETLINK. Userpace should then fallback to other means.

  To retain backwards compatibility the kernel will first check whether a
  IFLA_NET_NS_PID or IFLA_NET_NS_FD property has been passed. If either
  one is found it will be used to identify the target network namespace.
  This implies that users who do not care whether their running kernel
  supports IFLA_IF_NETNSID with RTM_SETLINK can pass both
  IFLA_NET_NS_{FD,PID} and IFLA_IF_NETNSID referring to the same network
  namespace.

- Security:
  Callers must have CAP_NET_ADMIN in the owning user namespace of the
  target network namespace.
Signed-off-by: NChristian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

RTM_{NEW,SET}LINK already allow operations on other network namespaces
by identifying the target network namespace through IFLA_NET_NS_{FD,PID}
properties. This is done by looking for the corresponding properties in
do_setlink(). Extend do_setlink() to also look for the IFLA_IF_NETNSID
property. This introduces no functional changes since all callers of
do_setlink() currently block IFLA_IF_NETNSID by reporting an error before
they reach do_setlink().

This introduces the helpers:

static struct net *rtnl_link_get_net_by_nlattr(struct net *src_net, struct
                                               nlattr *tb[])

static struct net *rtnl_link_get_net_capable(const struct sk_buff *skb,
                                             struct net *src_net,
					     struct nlattr *tb[], int cap)

to simplify permission checks and target network namespace retrieval for
RTM_* requests that already support IFLA_NET_NS_{FD,PID} but get extended
to IFLA_IF_NETNSID. To perserve backwards compatibility the helpers look
for IFLA_NET_NS_{FD,PID} properties first before checking for
IFLA_IF_NETNSID.
Signed-off-by: NChristian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

One of the ugly leftovers from the early eBPF days is that div/mod
operations based on registers have a hard-coded src_reg == 0 test
in the interpreter as well as in JIT code generators that would
return from the BPF program with exit code 0. This was basically
adopted from cBPF interpreter for historical reasons.

There are multiple reasons why this is very suboptimal and prone
to bugs. To name one: the return code mapping for such abnormal
program exit of 0 does not always match with a suitable program
type's exit code mapping. For example, '0' in tc means action 'ok'
where the packet gets passed further up the stack, which is just
undesirable for such cases (e.g. when implementing policy) and
also does not match with other program types.

While trying to work out an exception handling scheme, I also
noticed that programs crafted like the following will currently
pass the verifier:

  0: (bf) r6 = r1
  1: (85) call pc+8
  caller:
   R6=ctx(id=0,off=0,imm=0) R10=fp0,call_-1
  callee:
   frame1: R1=ctx(id=0,off=0,imm=0) R10=fp0,call_1
  10: (b4) (u32) r2 = (u32) 0
  11: (b4) (u32) r3 = (u32) 1
  12: (3c) (u32) r3 /= (u32) r2
  13: (61) r0 = *(u32 *)(r1 +76)
  14: (95) exit
  returning from callee:
   frame1: R0_w=pkt(id=0,off=0,r=0,imm=0)
           R1=ctx(id=0,off=0,imm=0) R2_w=inv0
           R3_w=inv(id=0,umax_value=4294967295,var_off=(0x0; 0xffffffff))
           R10=fp0,call_1
  to caller at 2:
   R0_w=pkt(id=0,off=0,r=0,imm=0) R6=ctx(id=0,off=0,imm=0)
   R10=fp0,call_-1

  from 14 to 2: R0=pkt(id=0,off=0,r=0,imm=0)
                R6=ctx(id=0,off=0,imm=0) R10=fp0,call_-1
  2: (bf) r1 = r6
  3: (61) r1 = *(u32 *)(r1 +80)
  4: (bf) r2 = r0
  5: (07) r2 += 8
  6: (2d) if r2 > r1 goto pc+1
   R0=pkt(id=0,off=0,r=8,imm=0) R1=pkt_end(id=0,off=0,imm=0)
   R2=pkt(id=0,off=8,r=8,imm=0) R6=ctx(id=0,off=0,imm=0)
   R10=fp0,call_-1
  7: (71) r0 = *(u8 *)(r0 +0)
  8: (b7) r0 = 1
  9: (95) exit

  from 6 to 8: safe
  processed 16 insns (limit 131072), stack depth 0+0

Basically what happens is that in the subprog we make use of a
div/mod by 0 exception and in the 'normal' subprog's exit path
we just return skb->data back to the main prog. This has the
implication that the verifier thinks we always get a pkt pointer
in R0 while we still have the implicit 'return 0' from the div
as an alternative unconditional return path earlier. Thus, R0
then contains 0, meaning back in the parent prog we get the
address range of [0x0, skb->data_end] as read and writeable.
Similar can be crafted with other pointer register types.

Since i) BPF_ABS/IND is not allowed in programs that contain
BPF to BPF calls (and generally it's also disadvised to use in
native eBPF context), ii) unknown opcodes don't return zero
anymore, iii) we don't return an exception code in dead branches,
the only last missing case affected and to fix is the div/mod
handling.

What we would really need is some infrastructure to propagate
exceptions all the way to the original prog unwinding the
current stack and returning that code to the caller of the
BPF program. In user space such exception handling for similar
runtimes is typically implemented with setjmp(3) and longjmp(3)
as one possibility which is not available in the kernel,
though (kgdb used to implement it in kernel long time ago). I
implemented a PoC exception handling mechanism into the BPF
interpreter with porting setjmp()/longjmp() into x86_64 and
adding a new internal BPF_ABRT opcode that can use a program
specific exception code for all exception cases we have (e.g.
div/mod by 0, unknown opcodes, etc). While this seems to work
in the constrained BPF environment (meaning, here, we don't
need to deal with state e.g. from memory allocations that we
would need to undo before going into exception state), it still
has various drawbacks: i) we would need to implement the
setjmp()/longjmp() for every arch supported in the kernel and
for x86_64, arm64, sparc64 JITs currently supporting calls,
ii) it has unconditional additional cost on main program
entry to store CPU register state in initial setjmp() call,
and we would need some way to pass the jmp_buf down into
___bpf_prog_run() for main prog and all subprogs, but also
storing on stack is not really nice (other option would be
per-cpu storage for this, but it also has the drawback that
we need to disable preemption for every BPF program types).
All in all this approach would add a lot of complexity.

Another poor-man's solution would be to have some sort of
additional shared register or scratch buffer to hold state
for exceptions, and test that after every call return to
chain returns and pass R0 all the way down to BPF prog caller.
This is also problematic in various ways: i) an additional
register doesn't map well into JITs, and some other scratch
space could only be on per-cpu storage, which, again has the
side-effect that this only works when we disable preemption,
or somewhere in the input context which is not available
everywhere either, and ii) this adds significant runtime
overhead by putting conditionals after each and every call,
as well as implementation complexity.

Yet another option is to teach verifier that div/mod can
return an integer, which however is also complex to implement
as verifier would need to walk such fake 'mov r0,<code>; exit;'
sequeuence and there would still be no guarantee for having
propagation of this further down to the BPF caller as proper
exception code. For parent prog, it is also is not distinguishable
from a normal return of a constant scalar value.

The approach taken here is a completely different one with
little complexity and no additional overhead involved in
that we make use of the fact that a div/mod by 0 is undefined
behavior. Instead of bailing out, we adapt the same behavior
as on some major archs like ARMv8 [0] into eBPF as well:
X div 0 results in 0, and X mod 0 results in X. aarch64 and
aarch32 ISA do not generate any traps or otherwise aborts
of program execution for unsigned divides. I verified this
also with a test program compiled by gcc and clang, and the
behavior matches with the spec. Going forward we adapt the
eBPF verifier to emit such rewrites once div/mod by register
was seen. cBPF is not touched and will keep existing 'return 0'
semantics. Given the options, it seems the most suitable from
all of them, also since major archs have similar schemes in
place. Given this is all in the realm of undefined behavior,
we still have the option to adapt if deemed necessary and
this way we would also have the option of more flexibility
from LLVM code generation side (which is then fully visible
to verifier). Thus, this patch i) fixes the panic seen in
above program and ii) doesn't bypass the verifier observations.

  [0] ARM Architecture Reference Manual, ARMv8 [ARM DDI 0487B.b]
      http://infocenter.arm.com/help/topic/com.arm.doc.ddi0487b.b/DDI0487B_b_armv8_arm.pdf
      1) aarch64 instruction set: section C3.4.7 and C6.2.279 (UDIV)
         "A division by zero results in a zero being written to
          the destination register, without any indication that
          the division by zero occurred."
      2) aarch32 instruction set: section F1.4.8 and F5.1.263 (UDIV)
         "For the SDIV and UDIV instructions, division by zero
          always returns a zero result."

Fixes: f4d7e40a ("bpf: introduce function calls (verification)")
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

Very minor optimization; saves 1 byte per program in x86_64
JIT in cBPF prologue.
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

Adds direct write access to sk_txhash and access to tclass for ipv6
flows through getsockopt and setsockopt. Sample usage for tclass:

  bpf_getsockopt(skops, SOL_IPV6, IPV6_TCLASS, &v, sizeof(v))

where skops is a pointer to the ctx (struct bpf_sock_ops).
Signed-off-by: NLawrence Brakmo <brakmo@fb.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

Add support for reading many more tcp_sock fields

  state,	same as sk->sk_state
  rtt_min	same as sk->rtt_min.s[0].v (current rtt_min)
  snd_ssthresh
  rcv_nxt
  snd_nxt
  snd_una
  mss_cache
  ecn_flags
  rate_delivered
  rate_interval_us
  packets_out
  retrans_out
  total_retrans
  segs_in
  data_segs_in
  segs_out
  data_segs_out
  lost_out
  sacked_out
  sk_txhash
  bytes_received (__u64)
  bytes_acked    (__u64)
Signed-off-by: NLawrence Brakmo <brakmo@fb.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

Adds field bpf_sock_ops_cb_flags to tcp_sock and bpf_sock_ops. Its primary
use is to determine if there should be calls to sock_ops bpf program at
various points in the TCP code. The field is initialized to zero,
disabling the calls. A sock_ops BPF program can set it, per connection and
as necessary, when the connection is established.

It also adds support for reading and writting the field within a
sock_ops BPF program. Reading is done by accessing the field directly.
However, writing is done through the helper function
bpf_sock_ops_cb_flags_set, in order to return an error if a BPF program
is trying to set a callback that is not supported in the current kernel
(i.e. running an older kernel). The helper function returns 0 if it was
able to set all of the bits set in the argument, a positive number
containing the bits that could not be set, or -EINVAL if the socket is
not a full TCP socket.

Examples of where one could call the bpf program:

1) When RTO fires
2) When a packet is retransmitted
3) When the connection terminates
4) When a packet is sent
5) When a packet is received
Signed-off-by: NLawrence Brakmo <brakmo@fb.com>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

This patch adds a macro, SOCK_OPS_SET_FIELD, for writing to
struct tcp_sock or struct sock fields. This required adding a new
field "temp" to struct bpf_sock_ops_kern for temporary storage that
is used by sock_ops_convert_ctx_access. It is used to store and recover
the contents of a register, so the register can be used to store the
address of the sk. Since we cannot overwrite the dst_reg because it
contains the pointer to ctx, nor the src_reg since it contains the value
we want to store, we need an extra register to contain the address
of the sk.

Also adds the macro SOCK_OPS_GET_OR_SET_FIELD that calls one of the
GET or SET macros depending on the value of the TYPE field.
Signed-off-by: NLawrence Brakmo <brakmo@fb.com>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

Changed SOCK_OPS_GET_TCP to SOCK_OPS_GET_FIELD and added 2
arguments so now it can also work with struct sock fields.
The first argument is the name of the field in the bpf_sock_ops
struct, the 2nd argument is the name of the field in the OBJ struct.

Previous: SOCK_OPS_GET_TCP(FIELD_NAME)
New:      SOCK_OPS_GET_FIELD(BPF_FIELD, OBJ_FIELD, OBJ)

Where OBJ is either "struct tcp_sock" or "struct sock" (without
quotation). BPF_FIELD is the name of the field in the bpf_sock_ops
struct and OBJ_FIELD is the name of the field in the OBJ struct.

Although the field names are currently the same, the kernel struct names
could change in the future and this change makes it easier to support
that.

Note that adding access to tcp_sock fields in sock_ops programs does
not preclude the tcp_sock fields from being removed as long as we are
willing to do one of the following:

  1) Return a fixed value (e.x. 0 or 0xffffffff), or
  2) Make the verifier fail if that field is accessed (i.e. program
    fails to load) so the user will know that field is no longer
    supported.
Signed-off-by: NLawrence Brakmo <brakmo@fb.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

Make SOCK_OPS_GET_TCP helper macro size independent (before only worked
with 4-byte fields.
Signed-off-by: NLawrence Brakmo <brakmo@fb.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

Currently, a sock_ops BPF program can write the op field and all the
reply fields (reply and replylong). This is a bug. The op field should
not have been writeable and there is currently no way to use replylong
field for indices >= 1. This patch enforces that only the reply field
(which equals replylong[0]) is writeable.

Fixes: 40304b2a ("bpf: BPF support for sock_ops")
Signed-off-by: NLawrence Brakmo <brakmo@fb.com>
Acked-by: NYuchung Cheng <ycheng@google.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

Currently, we unhash a dying net from netns_ids lists
under rtnl_lock(). It's a leftover from the time when
net::netns_ids was introduced. There was no net::nsid_lock,
and rtnl_lock() was mostly need to order modification
of alive nets nsid idr, i.e. for:
	for_each_net(tmp) {
		...
		id = __peernet2id(tmp, net);
		idr_remove(&tmp->netns_ids, id);
		...
	}

Since we have net::nsid_lock, the modifications are
protected by this local lock, and now we may introduce
better scheme of netns_ids destruction.

Let's look at the functions peernet2id_alloc() and
get_net_ns_by_id(). Previous commits taught these
functions to work well with dying net acquired from
rtnl unlocked lists. And they are the only functions
which can hash a net to netns_ids or obtain from there.
And as easy to check, other netns_ids operating functions
works with id, not with net pointers. So, we do not
need rtnl_lock to synchronize cleanup_net() with all them.

The another property, which is used in the patch,
is that net is unhashed from net_namespace_list
in the only place and by the only process. So,
we avoid excess rcu_read_lock() or rtnl_lock(),
when we'are iterating over the list in unhash_nsid().

All the above makes possible to keep rtnl_lock() locked
only for net->list deletion, and completely avoid it
for netns_ids unhashing and destruction. As these two
doings may take long time (e.g., memory allocation
to send skb), the patch should positively act on
the scalability and signify decrease the time, which
rtnl_lock() is held in cleanup_net().
Signed-off-by: NKirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Only two of dev_ioctl() callers may pass SIOCGIFCONF to it.
Separating that codepath from the rest of dev_ioctl() allows both
to simplify dev_ioctl() itself (all other cases work with struct ifreq *)
*and* seriously simplify the compat side of that beast: all it takes
is passing to inet_gifconf() an extra argument - the size of individual
records (sizeof(struct ifreq) or sizeof(struct compat_ifreq)).  With
dev_ifconf() called directly from sock_do_ioctl()/compat_dev_ifconf()
that's easy to arrange.

As the result, compat side of SIOCGIFCONF doesn't need any
allocations, copy_in_user() back and forth, etc.
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Don't use error-prone-brute-force way.
Signed-off-by: NDmitry Safonov <dima@arista.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add macro generated pkt_flag_names array, with a little help of which
the flags can be printed by using an index.
Signed-off-by: NDmitry Safonov <dima@arista.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

PKT_FALGS macro will be used to add package behavior names definitions
to simplify the code that prints/reads pkg flags.
Sorted the array in order of printing the flags in pktgen_if_show()
Note: Renamed IPSEC_ON => IPSEC for simplicity.

No visible behavior change expected.
Signed-off-by: NDmitry Safonov <dima@arista.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

o FLOW_SEQ now can be disabled with pgset "flag !FLOW_SEQ"
o FLOW_SEQ and FLOW_RND are antonyms, as it's shown by pktgen_if_show()
o IPSEC now may be disabled

Note, that IPV6 is enabled with dst6/src6 parameters, not with
a flag parameter.
Signed-off-by: NDmitry Safonov <dima@arista.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It takes 1sec for bond link down notification to hit user-space
when all slaves of the bond go down. 1sec is too long for
protocol daemons in user-space relying on bond notification
to recover (eg: multichassis lag implementations in user-space).
Since the link event code already marks team device port link events
 as urgent, this patch moves the code to cover all lag ports and master.
Signed-off-by: NRoopa Prabhu <roopa@cumulusnetworks.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Reviewed-by: NNikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fixes the following warnings:
./net/core/dev.c:6438: warning: No description found for parameter 'extack'
./net/core/dev.c:6461: warning: No description found for parameter 'extack'

Fixes: 42ab19ee ("net: Add extack to upper device linking")
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Remove the @dev comment, since we do not have a net_device argument, fixes the
following kernel doc warning: /net/core/dev.c:1707: warning: Excess function
parameter 'dev' description in 'call_netdevice_notifiers_info'
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Without proper validation of DODGY packets, we might very well
feed qdisc_pkt_len_init() with invalid GSO packets.

tcp_hdrlen() might access out-of-bound data, so let's use
skb_header_pointer() and proper checks.

Whole story is described in commit d0c081b4 ("flow_dissector:
properly cap thoff field")

We have the goal of validating DODGY packets earlier in the stack,
so we might very well revert this fix in the future.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Jason Wang <jasowang@redhat.com>
Reported-by: syzbot+9da69ebac7dddd804552@syzkaller.appspotmail.com
Acked-by: NJason Wang <jasowang@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Expose the number of times the link has been going UP or DOWN, and
update the "carrier_changes" counter to be the sum of these two events.
While at it, also update the sysfs-class-net documentation to cover:
carrier_changes (3.15), carrier_up_count (4.16) and carrier_down_count
(4.16)
Signed-off-by: NDavid Decotigny <decot@googlers.com>
[Florian:
* rebase
* add documentation
* merge carrier_changes with up/down counters]
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently, if the call to devlink_resource_find returns null then
the error exit path does not free the devlink_resource 'resource'
and a memory leak occurs. Fix this by kfree'ing resource on the
error exit path.

Detected by CoverityScan, CID#1464184 ("Resource leak")

Fixes: d9f9b9a4 ("devlink: Add support for resource abstraction")
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Similar rationale as in a60dd35d ("bpf: change bpf_perf_event_output
arg5 type to ARG_CONST_SIZE_OR_ZERO"), change the type to CONST_SIZE_OR_ZERO
such that we can better deal with optimized code. No changes needed in
bpf_event_output() as it can also deal with 0 size entirely (e.g. as only
wake-up signal with empty frame in perf RB, or packet dumps w/o meta data
as another such possibility).
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

Given BPF reaches far beyond just networking these days, it was
never intended to allow setting and in some cases reading those
knobs out of a user namespace root running without CAP_SYS_ADMIN,
thus tighten such access.

Also the bpf_jit_enable = 2 debugging mode should only be allowed
if kptr_restrict is not set since it otherwise can leak addresses
to the kernel log. Dump a note to the kernel log that this is for
debugging JITs only when enabled.
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

Having a pure_initcall() callback just to permanently enable BPF
JITs under CONFIG_BPF_JIT_ALWAYS_ON is unnecessary and could leave
a small race window in future where JIT is still disabled on boot.
Since we know about the setting at compilation time anyway, just
initialize it properly there. Also consolidate all the individual
bpf_jit_enable variables into a single one and move them under one
location. Moreover, don't allow for setting unspecified garbage
values on them.
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

Useful for porting cls_bpf programs w/o increasing program
complexity limits much at the same time, so add the helper
to XDP as well.
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

Fixes the following sparse warnings:

net/core/devlink.c:2297:25: warning:
 symbol 'devlink_resource_find' was not declared. Should it be static?
net/core/devlink.c:2322:6: warning:
 symbol 'devlink_resource_validate_children' was not declared. Should it be static?
Signed-off-by: NWei Yongjun <weiyongjun1@huawei.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

in order to improve test coverage allow socket_filter program type
to be run via bpf_prog_test_run command.
Since such programs can be loaded by non-root tighten
permissions for bpf_prog_test_run to be root only
to avoid surprises.
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

syzbot reported yet another crash [1] that is caused by
insufficient validation of DODGY packets.

Two bugs are happening here to trigger the crash.

1) Flow dissection leaves with incorrect thoff field.

2) skb_probe_transport_header() sets transport header to this invalid
thoff, even if pointing after skb valid data.

3) qdisc_pkt_len_init() reads out-of-bound data because it
trusts tcp_hdrlen(skb)

Possible fixes :

- Full flow dissector validation before injecting bad DODGY packets in
the stack.
 This approach was attempted here : https://patchwork.ozlabs.org/patch/
861874/

- Have more robust functions in the core.
  This might be needed anyway for stable versions.

This patch fixes the flow dissection issue.

[1]
CPU: 1 PID: 3144 Comm: syzkaller271204 Not tainted 4.15.0-rc4-mm1+ #49
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x194/0x257 lib/dump_stack.c:53
 print_address_description+0x73/0x250 mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:355 [inline]
 kasan_report+0x23b/0x360 mm/kasan/report.c:413
 __asan_report_load2_noabort+0x14/0x20 mm/kasan/report.c:432
 __tcp_hdrlen include/linux/tcp.h:35 [inline]
 tcp_hdrlen include/linux/tcp.h:40 [inline]
 qdisc_pkt_len_init net/core/dev.c:3160 [inline]
 __dev_queue_xmit+0x20d3/0x2200 net/core/dev.c:3465
 dev_queue_xmit+0x17/0x20 net/core/dev.c:3554
 packet_snd net/packet/af_packet.c:2943 [inline]
 packet_sendmsg+0x3ad5/0x60a0 net/packet/af_packet.c:2968
 sock_sendmsg_nosec net/socket.c:628 [inline]
 sock_sendmsg+0xca/0x110 net/socket.c:638
 sock_write_iter+0x31a/0x5d0 net/socket.c:907
 call_write_iter include/linux/fs.h:1776 [inline]
 new_sync_write fs/read_write.c:469 [inline]
 __vfs_write+0x684/0x970 fs/read_write.c:482
 vfs_write+0x189/0x510 fs/read_write.c:544
 SYSC_write fs/read_write.c:589 [inline]
 SyS_write+0xef/0x220 fs/read_write.c:581
 entry_SYSCALL_64_fastpath+0x1f/0x96

Fixes: 34fad54c ("net: __skb_flow_dissect() must cap its return value")
Fixes: a6e544b0 ("flow_dissector: Jump to exit code in __skb_flow_dissect")
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Reported-by: Nsyzbot <syzkaller@googlegroups.com>
Acked-by: NJason Wang <jasowang@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

idr_find() is safe under rcu_read_lock() and
maybe_get_net() guarantees that net is alive.
Signed-off-by: NKirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

peernet2id_alloc() is racy without rtnl_lock() as refcount_read(&peer->count)
under net->nsid_lock does not guarantee, peer is alive:

rcu_read_lock()
peernet2id_alloc()                            ..
  spin_lock_bh(&net->nsid_lock)               ..
  refcount_read(&peer->count) (!= 0)          ..
  ..                                          put_net()
  ..                                            cleanup_net()
  ..                                              for_each_net(tmp)
  ..                                                spin_lock_bh(&tmp->nsid_lock)
  ..                                                __peernet2id(tmp, net) == -1
  ..                                                    ..
  ..                                                    ..
    __peernet2id_alloc(alloc == true)                   ..
  ..                                                    ..
rcu_read_unlock()                                       ..
..                                                synchronize_rcu()
..                                                kmem_cache_free(net)

After the above situation, net::netns_id contains id pointing to freed memory,
and any other dereferencing by the id will operate with this freed memory.

Currently, peernet2id_alloc() is used under rtnl_lock() everywhere except
ovs_vport_cmd_fill_info(), and this race can't occur. But peernet2id_alloc()
is generic interface, and better we fix it before someone really starts
use it in wrong context.

v2: Don't place refcount_read(&net->count) under net->nsid_lock
    as suggested by Eric W. Biederman <ebiederm@xmission.com>
v3: Rebase on top of net-next
Signed-off-by: NKirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

/proc has been ignoring struct file_operations::owner field for 10 years.
Specifically, it started with commit 786d7e16
("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: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The hardware processes which are modeled via dpipe commonly use some
internal hardware resources. Such relation can improve the understanding
of hardware limitations. The number of resource's unit consumed per
table's entry are also provided for each table.
Signed-off-by: NArkadi Sharshevsky <arkadis@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add support for performing driver hot reload.
Signed-off-by: NArkadi Sharshevsky <arkadis@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>