Commit Graph

5939 Commits

Author SHA1 Message Date
Masahiro Yamada d5470d1443 kbuild: re-implement Makefile.headersinst without recursion
Since commit fcc8487d47 ("uapi: export all headers under uapi
directories"), the headers in uapi directories are all exported by
default although exceptional cases are still allowed by the syntax
'no-export-headers'.

The traditional directory descending has been kept (in a somewhat
hacky way), but it is actually unneeded.

Get rid of it to simplify the code.

Also, handle files one by one instead of the previous per-directory
processing. This will emit much more log, but I like it.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-06-15 19:57:02 +09:00
Stanislav Fomichev 1314ef5611 bpf: export bpf_sock for BPF_PROG_TYPE_SOCK_OPS prog type
And let it use bpf_sk_storage_{get,delete} helpers to access socket
storage. Kernel context (struct bpf_sock_ops_kern) already has sk
member, so I just expose it to the BPF hooks. I use
PTR_TO_SOCKET_OR_NULL and return NULL in !is_fullsock case.

I also export bpf_tcp_sock to make it possible to access tcp socket stats.

Cc: Martin Lau <kafai@fb.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-06-15 01:21:57 +02:00
Stanislav Fomichev fb85c4a730 bpf: export bpf_sock for BPF_PROG_TYPE_CGROUP_SOCK_ADDR prog type
And let it use bpf_sk_storage_{get,delete} helpers to access socket
storage. Kernel context (struct bpf_sock_addr_kern) already has sk
member, so I just expose it to the BPF hooks. Using PTR_TO_SOCKET
instead of PTR_TO_SOCK_COMMON should be safe because the hook is
called on bind/connect.

Cc: Martin Lau <kafai@fb.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-06-15 01:21:56 +02:00
Mauro Carvalho Chehab 99c8b231ae docs: cgroup-v1: convert docs to ReST and rename to *.rst
Convert the cgroup-v1 files to ReST format, in order to
allow a later addition to the admin-guide.

The conversion is actually:
  - add blank lines and identation in order to identify paragraphs;
  - fix tables markups;
  - add some lists markups;
  - mark literal blocks;
  - adjust title markups.

At its new index.rst, let's add a :orphan: while this is not linked to
the main index.rst file, in order to avoid build warnings.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
2019-06-14 13:29:54 -07:00
David S. Miller d96ec97511 Merge tag 'mac80211-next-for-davem-2019-06-14' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next
Johannes Berg says:

====================
Many changes all over:
 * HE (802.11ax) work continues
 * WPA3 offloads
 * work on extended key ID handling continues
 * fixes to honour AP supported rates with auth/assoc frames
 * nl80211 netlink policy improvements to fix some issues
   with strict validation on new commands with old attrs
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-14 11:27:26 -07:00
John Crispin a0de1ca383 mac80211: allow turning TWT responder support on and off via netlink
Allow the userland daemon to en/disable TWT support for an AP.

Signed-off-by: Shashidhar Lakkavalli <slakkavalli@datto.com>
Signed-off-by: John Crispin <john@phrozen.org>
[simplify parsing code]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-06-14 14:14:10 +02:00
Chung-Hsien Hsu 26f7044e95 nl80211: add support for SAE authentication offload
Let drivers advertise support for station-mode SAE authentication
offload with a new NL80211_EXT_FEATURE_SAE_OFFLOAD flag.

Signed-off-by: Chung-Hsien Hsu <stanley.hsu@cypress.com>
Signed-off-by: Chi-Hsien Lin <chi-hsien.lin@cypress.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-06-14 14:07:49 +02:00
Chung-Hsien Hsu cc3e14c21a nl80211: add WPA3 definition for SAE authentication
Add definition of WPA version 3 for SAE authentication.

Signed-off-by: Chung-Hsien Hsu <stanley.hsu@cypress.com>
Signed-off-by: Chi-Hsien Lin <chi-hsien.lin@cypress.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-06-14 14:07:34 +02:00
Greg Hackmann bb2bb90304 dma-buf: add DMA_BUF_SET_NAME ioctls
This patch adds complimentary DMA_BUF_SET_NAME  ioctls, which lets
userspace processes attach a free-form name to each buffer.

This information can be extremely helpful for tracking and accounting
shared buffers.  For example, on Android, we know what each buffer will
be used for at allocation time: GL, multimedia, camera, etc.  The
userspace allocator can use DMA_BUF_SET_NAME to associate that
information with the buffer, so we can later give developers a
breakdown of how much memory they're allocating for graphics, camera,
etc.

Signed-off-by: Greg Hackmann <ghackmann@google.com>
Signed-off-by: Chenbo Feng <fengc@google.com>
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190613223408.139221-3-fengc@google.com
2019-06-14 15:00:51 +05:30
Greg Hackmann ed63bb1d1f dma-buf: give each buffer a full-fledged inode
By traversing /proc/*/fd and /proc/*/map_files, processes with CAP_ADMIN
can get a lot of fine-grained data about how shmem buffers are shared
among processes.  stat(2) on each entry gives the caller a unique
ID (st_ino), the buffer's size (st_size), and even the number of pages
currently charged to the buffer (st_blocks / 512).

In contrast, all dma-bufs share the same anonymous inode.  So while we
can count how many dma-buf fds or mappings a process has, we can't get
the size of the backing buffers or tell if two entries point to the same
dma-buf.  On systems with debugfs, we can get a per-buffer breakdown of
size and reference count, but can't tell which processes are actually
holding the references to each buffer.

Replace the singleton inode with full-fledged inodes allocated by
alloc_anon_inode().  This involves creating and mounting a
mini-pseudo-filesystem for dma-buf, following the example in fs/aio.c.

Signed-off-by: Greg Hackmann <ghackmann@google.com>
Signed-off-by: Chenbo Feng <fengc@google.com>
Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190613223408.139221-2-fengc@google.com
2019-06-14 15:00:50 +05:30
Gustavo Pimentel de76cda215 PCI: Decode PCIe 32 GT/s link speed
PCIe r5.0, sec 7.5.3.18, defines a new 32.0 GT/s bit in the Supported Link
Speeds Vector of Link Capabilities 2.  Decode this new speed.  This does
not affect the speed of the link, which should be negotiated automatically
by the hardware; it only adds decoding when showing the speed to the user.

Previously, reading the speed of a link operating at this speed showed
"Unknown speed" instead of "32.0 GT/s".

Link: https://lore.kernel.org/lkml/92365e3caf0fc559f9ab14bcd053bfc92d4f661c.1559664969.git.gustavo.pimentel@synopsys.com
Signed-off-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
[bhelgaas: changelog]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2019-06-13 16:49:45 -05:00
Martynas Pumputis b1d6c15b9d bpf: simplify definition of BPF_FIB_LOOKUP related flags
Previously, the BPF_FIB_LOOKUP_{DIRECT,OUTPUT} flags in the BPF UAPI
were defined with the help of BIT macro. This had the following issues:

- In order to use any of the flags, a user was required to depend
  on <linux/bits.h>.
- No other flag in bpf.h uses the macro, so it seems that an unwritten
  convention is to use (1 << (nr)) to define BPF-related flags.

Fixes: 87f5fc7e48 ("bpf: Provide helper to do forwarding lookups in kernel FIB table")
Signed-off-by: Martynas Pumputis <m@lambda.lt>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-06-13 22:43:42 +02:00
Eric Dumazet a842fe1425 tcp: add optional per socket transmit delay
Adding delays to TCP flows is crucial for studying behavior
of TCP stacks, including congestion control modules.

Linux offers netem module, but it has unpractical constraints :
- Need root access to change qdisc
- Hard to setup on egress if combined with non trivial qdisc like FQ
- Single delay for all flows.

EDT (Earliest Departure Time) adoption in TCP stack allows us
to enable a per socket delay at a very small cost.

Networking tools can now establish thousands of flows, each of them
with a different delay, simulating real world conditions.

This requires FQ packet scheduler or a EDT-enabled NIC.

This patchs adds TCP_TX_DELAY socket option, to set a delay in
usec units.

  unsigned int tx_delay = 10000; /* 10 msec */

  setsockopt(fd, SOL_TCP, TCP_TX_DELAY, &tx_delay, sizeof(tx_delay));

Note that FQ packet scheduler limits might need some tweaking :

man tc-fq

PARAMETERS
   limit
       Hard  limit  on  the  real  queue  size. When this limit is
       reached, new packets are dropped. If the value is  lowered,
       packets  are  dropped so that the new limit is met. Default
       is 10000 packets.

   flow_limit
       Hard limit on the maximum  number  of  packets  queued  per
       flow.  Default value is 100.

Use of TCP_TX_DELAY option will increase number of skbs in FQ qdisc,
so packets would be dropped if any of the previous limit is hit.

Use of a jump label makes this support runtime-free, for hosts
never using the option.

Also note that TSQ (TCP Small Queues) limits are slightly changed
with this patch : we need to account that skbs artificially delayed
wont stop us providind more skbs to feed the pipe (netem uses
skb_orphan_partial() for this purpose, but FQ can not use this trick)

Because of that, using big delays might very well trigger
old bugs in TSO auto defer logic and/or sndbuf limited detection.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-12 13:05:43 -07:00
Jean-Philippe Brucker bf3255b3cf iommu: Add recoverable fault reporting
Some IOMMU hardware features, for example PCI PRI and Arm SMMU Stall,
enable recoverable I/O page faults. Allow IOMMU drivers to report PRI Page
Requests and Stall events through the new fault reporting API. The
consumer of the fault can be either an I/O page fault handler in the host,
or a guest OS.

Once handled, the fault must be completed by sending a page response back
to the IOMMU. Add an iommu_page_response() function to complete a page
fault.

There are two ways to extend the userspace API:
* Add a field to iommu_page_response and a flag to
  iommu_page_response::flags describing the validity of this field.
* Introduce a new iommu_page_response_X structure with a different version
  number. The kernel must then support both versions.

Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-06-12 10:19:06 +02:00
Jacob Pan 4e32348ba5 iommu: Introduce device fault data
Device faults detected by IOMMU can be reported outside the IOMMU
subsystem for further processing. This patch introduces
a generic device fault data structure.

The fault can be either an unrecoverable fault or a page request,
also referred to as a recoverable fault.

We only care about non internal faults that are likely to be reported
to an external subsystem.

Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Signed-off-by: Liu, Yi L <yi.l.liu@linux.intel.com>
Signed-off-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2019-06-12 10:19:06 +02:00
Mauro Carvalho Chehab 5800571960 Merge tag 'v5.2-rc4' into media/master
There are some conflicts due to SPDX changes. We also have more
patches being merged via media tree touching them.

So, let's merge back from upstream and address those.

Linux 5.2-rc4

* tag 'v5.2-rc4': (767 commits)
  Linux 5.2-rc4
  MAINTAINERS: Karthikeyan Ramasubramanian is MIA
  i2c: xiic: Add max_read_len quirk
  lockref: Limit number of cmpxchg loop retries
  uaccess: add noop untagged_addr definition
  x86/insn-eval: Fix use-after-free access to LDT entry
  kbuild: use more portable 'command -v' for cc-cross-prefix
  s390/unwind: correct stack switching during unwind
  block, bfq: add weight symlink to the bfq.weight cgroup parameter
  cgroup: let a symlink too be created with a cftype file
  drm/nouveau/secboot/gp10[2467]: support newer FW to fix SEC2 failures on some boards
  drm/nouveau/secboot: enable loading of versioned LS PMU/SEC2 ACR msgqueue FW
  drm/nouveau/secboot: split out FW version-specific LS function pointers
  drm/nouveau/secboot: pass max supported FW version to LS load funcs
  drm/nouveau/core: support versioned firmware loading
  drm/nouveau/core: pass subdev into nvkm_firmware_get, rather than device
  block: free sched's request pool in blk_cleanup_queue
  pktgen: do not sleep with the thread lock held.
  net: mvpp2: Use strscpy to handle stat strings
  net: rds: fix memory leak in rds_ib_flush_mr_pool
  ...

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2019-06-11 12:09:28 -04:00
Jonathan Lemon fada7fdc83 bpf: Allow bpf_map_lookup_elem() on an xskmap
Currently, the AF_XDP code uses a separate map in order to
determine if an xsk is bound to a queue.  Instead of doing this,
have bpf_map_lookup_elem() return a xdp_sock.

Rearrange some xdp_sock members to eliminate structure holes.

Remove selftest - will be added back in later patch.

Signed-off-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-06-10 23:31:26 -07:00
Jozsef Kadlecsik fe03d47456 Update my email address
It's better to use my kadlec@netfilter.org email address in
the source code. I might not be able to use
kadlec@blackhole.kfki.hu in the future.

Signed-off-by: Jozsef Kadlecsik <kadlec@netfilter.org>
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
2019-06-10 13:00:24 +02:00
Christian Brauner 7f192e3cd3 fork: add clone3
This adds the clone3 system call.

As mentioned several times already (cf. [7], [8]) here's the promised
patchset for clone3().

We recently merged the CLONE_PIDFD patchset (cf. [1]). It took the last
free flag from clone().

Independent of the CLONE_PIDFD patchset a time namespace has been discussed
at Linux Plumber Conference last year and has been sent out and reviewed
(cf. [5]). It is expected that it will go upstream in the not too distant
future. However, it relies on the addition of the CLONE_NEWTIME flag to
clone(). The only other good candidate - CLONE_DETACHED - is currently not
recyclable as we have identified at least two large or widely used
codebases that currently pass this flag (cf. [2], [3], and [4]). Given that
CLONE_PIDFD grabbed the last clone() flag the time namespace is effectively
blocked. clone3() has the advantage that it will unblock this patchset
again. In general, clone3() is extensible and allows for the implementation
of new features.

The idea is to keep clone3() very simple and close to the original clone(),
specifically, to keep on supporting old clone()-based workloads.
We know there have been various creative proposals how a new process
creation syscall or even api is supposed to look like. Some people even
going so far as to argue that the traditional fork()+exec() split should be
abandoned in favor of an in-kernel version of spawn(). Independent of
whether or not we personally think spawn() is a good idea this patchset has
and does not want to have anything to do with this.
One stance we take is that there's no real good alternative to
clone()+exec() and we need and want to support this model going forward;
independent of spawn().
The following requirements guided clone3():
- bump the number of available flags
- move arguments that are currently passed as separate arguments
  in clone() into a dedicated struct clone_args
  - choose a struct layout that is easy to handle on 32 and on 64 bit
  - choose a struct layout that is extensible
  - give new flags that currently need to abuse another flag's dedicated
    return argument in clone() their own dedicated return argument
    (e.g. CLONE_PIDFD)
  - use a separate kernel internal struct kernel_clone_args that is
    properly typed according to current kernel conventions in fork.c and is
    different from  the uapi struct clone_args
- port _do_fork() to use kernel_clone_args so that all process creation
  syscalls such as fork(), vfork(), clone(), and clone3() behave identical
  (Arnd suggested, that we can probably also port do_fork() itself in a
   separate patchset.)
- ease of transition for userspace from clone() to clone3()
  This very much means that we do *not* remove functionality that userspace
  currently relies on as the latter is a good way of creating a syscall
  that won't be adopted.
- do not try to be clever or complex: keep clone3() as dumb as possible

In accordance with Linus suggestions (cf. [11]), clone3() has the following
signature:

/* uapi */
struct clone_args {
        __aligned_u64 flags;
        __aligned_u64 pidfd;
        __aligned_u64 child_tid;
        __aligned_u64 parent_tid;
        __aligned_u64 exit_signal;
        __aligned_u64 stack;
        __aligned_u64 stack_size;
        __aligned_u64 tls;
};

/* kernel internal */
struct kernel_clone_args {
        u64 flags;
        int __user *pidfd;
        int __user *child_tid;
        int __user *parent_tid;
        int exit_signal;
        unsigned long stack;
        unsigned long stack_size;
        unsigned long tls;
};

long sys_clone3(struct clone_args __user *uargs, size_t size)

clone3() cleanly supports all of the supported flags from clone() and thus
all legacy workloads.
The advantage of sticking close to the old clone() is the low cost for
userspace to switch to this new api. Quite a lot of userspace apis (e.g.
pthreads) are based on the clone() syscall. With the new clone3() syscall
supporting all of the old workloads and opening up the ability to add new
features should make switching to it for userspace more appealing. In
essence, glibc can just write a simple wrapper to switch from clone() to
clone3().

There has been some interest in this patchset already. We have received a
patch from the CRIU corner for clone3() that would set the PID/TID of a
restored process without /proc/sys/kernel/ns_last_pid to eliminate a race.

/* User visible differences to legacy clone() */
- CLONE_DETACHED will cause EINVAL with clone3()
- CSIGNAL is deprecated
  It is superseeded by a dedicated "exit_signal" argument in struct
  clone_args freeing up space for additional flags.
  This is based on a suggestion from Andrei and Linus (cf. [9] and [10])

/* References */
[1]: b3e5838252
[2]: https://dxr.mozilla.org/mozilla-central/source/security/sandbox/linux/SandboxFilter.cpp#343
[3]: https://git.musl-libc.org/cgit/musl/tree/src/thread/pthread_create.c#n233
[4]: https://sources.debian.org/src/blcr/0.8.5-2.3/cr_module/cr_dump_self.c/?hl=740#L740
[5]: https://lore.kernel.org/lkml/20190425161416.26600-1-dima@arista.com/
[6]: https://lore.kernel.org/lkml/20190425161416.26600-2-dima@arista.com/
[7]: https://lore.kernel.org/lkml/CAHrFyr5HxpGXA2YrKza-oB-GGwJCqwPfyhD-Y5wbktWZdt0sGQ@mail.gmail.com/
[8]: https://lore.kernel.org/lkml/20190524102756.qjsjxukuq2f4t6bo@brauner.io/
[9]: https://lore.kernel.org/lkml/20190529222414.GA6492@gmail.com/
[10]: https://lore.kernel.org/lkml/CAHk-=whQP-Ykxi=zSYaV9iXsHsENa+2fdj-zYKwyeyed63Lsfw@mail.gmail.com/
[11]: https://lore.kernel.org/lkml/CAHk-=wieuV4hGwznPsX-8E0G2FKhx3NjZ9X3dTKh5zKd+iqOBw@mail.gmail.com/

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Christian Brauner <christian@brauner.io>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Serge Hallyn <serge@hallyn.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Cc: Jann Horn <jannh@google.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Adrian Reber <adrian@lisas.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrei Vagin <avagin@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: linux-api@vger.kernel.org
2019-06-09 09:29:28 +02:00
David S. Miller 38e406f600 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:

====================
pull-request: bpf 2019-06-07

The following pull-request contains BPF updates for your *net* tree.

The main changes are:

1) Fix several bugs in riscv64 JIT code emission which forgot to clear high
   32-bits for alu32 ops, from Björn and Luke with selftests covering all
   relevant BPF alu ops from Björn and Jiong.

2) Two fixes for UDP BPF reuseport that avoid calling the program in case of
   __udp6_lib_err and UDP GRO which broke reuseport_select_sock() assumption
   that skb->data is pointing to transport header, from Martin.

3) Two fixes for BPF sockmap: a use-after-free from sleep in psock's backlog
   workqueue, and a missing restore of sk_write_space when psock gets dropped,
   from Jakub and John.

4) Fix unconnected UDP sendmsg hook API which is insufficient as-is since it
   breaks standard applications like DNS if reverse NAT is not performed upon
   receive, from Daniel.

5) Fix an out-of-bounds read in __bpf_skc_lookup which in case of AF_INET6
   fails to verify that the length of the tuple is long enough, from Lorenz.

6) Fix libbpf's libbpf__probe_raw_btf to return an fd instead of 0/1 (for
   {un,}successful probe) as that is expected to be propagated as an fd to
   load_sk_storage_btf() and thus closing the wrong descriptor otherwise,
   from Michal.

7) Fix bpftool's JSON output for the case when a lookup fails, from Krzesimir.

8) Minor misc fixes in docs, samples and selftests, from various others.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-07 14:46:47 -07:00
David S. Miller a6cdeeb16b Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Some ISDN files that got removed in net-next had some changes
done in mainline, take the removals.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-07 11:00:14 -07:00
Daniel Borkmann 983695fa67 bpf: fix unconnected udp hooks
Intention of cgroup bind/connect/sendmsg BPF hooks is to act transparently
to applications as also stated in original motivation in 7828f20e37 ("Merge
branch 'bpf-cgroup-bind-connect'"). When recently integrating the latter
two hooks into Cilium to enable host based load-balancing with Kubernetes,
I ran into the issue that pods couldn't start up as DNS got broken. Kubernetes
typically sets up DNS as a service and is thus subject to load-balancing.

Upon further debugging, it turns out that the cgroupv2 sendmsg BPF hooks API
is currently insufficient and thus not usable as-is for standard applications
shipped with most distros. To break down the issue we ran into with a simple
example:

  # cat /etc/resolv.conf
  nameserver 147.75.207.207
  nameserver 147.75.207.208

For the purpose of a simple test, we set up above IPs as service IPs and
transparently redirect traffic to a different DNS backend server for that
node:

  # cilium service list
  ID   Frontend            Backend
  1    147.75.207.207:53   1 => 8.8.8.8:53
  2    147.75.207.208:53   1 => 8.8.8.8:53

The attached BPF program is basically selecting one of the backends if the
service IP/port matches on the cgroup hook. DNS breaks here, because the
hooks are not transparent enough to applications which have built-in msg_name
address checks:

  # nslookup 1.1.1.1
  ;; reply from unexpected source: 8.8.8.8#53, expected 147.75.207.207#53
  ;; reply from unexpected source: 8.8.8.8#53, expected 147.75.207.208#53
  ;; reply from unexpected source: 8.8.8.8#53, expected 147.75.207.207#53
  [...]
  ;; connection timed out; no servers could be reached

  # dig 1.1.1.1
  ;; reply from unexpected source: 8.8.8.8#53, expected 147.75.207.207#53
  ;; reply from unexpected source: 8.8.8.8#53, expected 147.75.207.208#53
  ;; reply from unexpected source: 8.8.8.8#53, expected 147.75.207.207#53
  [...]

  ; <<>> DiG 9.11.3-1ubuntu1.7-Ubuntu <<>> 1.1.1.1
  ;; global options: +cmd
  ;; connection timed out; no servers could be reached

For comparison, if none of the service IPs is used, and we tell nslookup
to use 8.8.8.8 directly it works just fine, of course:

  # nslookup 1.1.1.1 8.8.8.8
  1.1.1.1.in-addr.arpa	name = one.one.one.one.

In order to fix this and thus act more transparent to the application,
this needs reverse translation on recvmsg() side. A minimal fix for this
API is to add similar recvmsg() hooks behind the BPF cgroups static key
such that the program can track state and replace the current sockaddr_in{,6}
with the original service IP. From BPF side, this basically tracks the
service tuple plus socket cookie in an LRU map where the reverse NAT can
then be retrieved via map value as one example. Side-note: the BPF cgroups
static key should be converted to a per-hook static key in future.

Same example after this fix:

  # cilium service list
  ID   Frontend            Backend
  1    147.75.207.207:53   1 => 8.8.8.8:53
  2    147.75.207.208:53   1 => 8.8.8.8:53

Lookups work fine now:

  # nslookup 1.1.1.1
  1.1.1.1.in-addr.arpa    name = one.one.one.one.

  Authoritative answers can be found from:

  # dig 1.1.1.1

  ; <<>> DiG 9.11.3-1ubuntu1.7-Ubuntu <<>> 1.1.1.1
  ;; global options: +cmd
  ;; Got answer:
  ;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 51550
  ;; flags: qr rd ra ad; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 1

  ;; OPT PSEUDOSECTION:
  ; EDNS: version: 0, flags:; udp: 512
  ;; QUESTION SECTION:
  ;1.1.1.1.                       IN      A

  ;; AUTHORITY SECTION:
  .                       23426   IN      SOA     a.root-servers.net. nstld.verisign-grs.com. 2019052001 1800 900 604800 86400

  ;; Query time: 17 msec
  ;; SERVER: 147.75.207.207#53(147.75.207.207)
  ;; WHEN: Tue May 21 12:59:38 UTC 2019
  ;; MSG SIZE  rcvd: 111

And from an actual packet level it shows that we're using the back end
server when talking via 147.75.207.20{7,8} front end:

  # tcpdump -i any udp
  [...]
  12:59:52.698732 IP foo.42011 > google-public-dns-a.google.com.domain: 18803+ PTR? 1.1.1.1.in-addr.arpa. (38)
  12:59:52.698735 IP foo.42011 > google-public-dns-a.google.com.domain: 18803+ PTR? 1.1.1.1.in-addr.arpa. (38)
  12:59:52.701208 IP google-public-dns-a.google.com.domain > foo.42011: 18803 1/0/0 PTR one.one.one.one. (67)
  12:59:52.701208 IP google-public-dns-a.google.com.domain > foo.42011: 18803 1/0/0 PTR one.one.one.one. (67)
  [...]

In order to be flexible and to have same semantics as in sendmsg BPF
programs, we only allow return codes in [1,1] range. In the sendmsg case
the program is called if msg->msg_name is present which can be the case
in both, connected and unconnected UDP.

The former only relies on the sockaddr_in{,6} passed via connect(2) if
passed msg->msg_name was NULL. Therefore, on recvmsg side, we act in similar
way to call into the BPF program whenever a non-NULL msg->msg_name was
passed independent of sk->sk_state being TCP_ESTABLISHED or not. Note
that for TCP case, the msg->msg_name is ignored in the regular recvmsg
path and therefore not relevant.

For the case of ip{,v6}_recv_error() paths, picked up via MSG_ERRQUEUE,
the hook is not called. This is intentional as it aligns with the same
semantics as in case of TCP cgroup BPF hooks right now. This might be
better addressed in future through a different bpf_attach_type such
that this case can be distinguished from the regular recvmsg paths,
for example.

Fixes: 1cedee13d2 ("bpf: Hooks for sys_sendmsg")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrey Ignatov <rdna@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Martynas Pumputis <m@lambda.lt>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-06-06 16:53:12 -07:00
Jean-Philippe Brucker 169a126c6e iommu/virtio: Add event queue
The event queue offers a way for the device to report access faults from
endpoints. It is implemented on virtqueue #1. Whenever the host needs to
signal a fault, it fills one of the buffers offered by the guest and
interrupts it.

Tested-by: Bharat Bhushan <bharat.bhushan@nxp.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-06-06 17:32:14 -04:00
Jean-Philippe Brucker 2a5a314874 iommu/virtio: Add probe request
When the device offers the probe feature, send a probe request for each
device managed by the IOMMU. Extract RESV_MEM information. When we
encounter a MSI doorbell region, set it up as a IOMMU_RESV_MSI region.
This will tell other subsystems that there is no need to map the MSI
doorbell in the virtio-iommu, because MSIs bypass it.

Tested-by: Bharat Bhushan <bharat.bhushan@nxp.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-06-06 17:32:14 -04:00
Jean-Philippe Brucker edcd69ab9a iommu: Add virtio-iommu driver
The virtio IOMMU is a para-virtualized device, allowing to send IOMMU
requests such as map/unmap over virtio transport without emulating page
tables. This implementation handles ATTACH, DETACH, MAP and UNMAP
requests.

The bulk of the code transforms calls coming from the IOMMU API into
corresponding virtio requests. Mappings are kept in an interval tree
instead of page tables. A little more work is required for modular and x86
support, so for the moment the driver depends on CONFIG_VIRTIO=y and
CONFIG_ARM64.

Tested-by: Bharat Bhushan <bharat.bhushan@nxp.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-06-06 17:32:13 -04:00