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27794 Commits (9ba8376ce1e2cbf4ce44f7e4bee1d0648e10d594)

Author SHA1 Message Date
Daniel Borkmann c7a8978432 bpf: don't leave partial mangled prog in jit_subprogs error path
syzkaller managed to trigger the following bug through fault injection:

  [...]
  [  141.043668] verifier bug. No program starts at insn 3
  [  141.044648] WARNING: CPU: 3 PID: 4072 at kernel/bpf/verifier.c:1613
                 get_callee_stack_depth kernel/bpf/verifier.c:1612 [inline]
  [  141.044648] WARNING: CPU: 3 PID: 4072 at kernel/bpf/verifier.c:1613
                 fixup_call_args kernel/bpf/verifier.c:5587 [inline]
  [  141.044648] WARNING: CPU: 3 PID: 4072 at kernel/bpf/verifier.c:1613
                 bpf_check+0x525e/0x5e60 kernel/bpf/verifier.c:5952
  [  141.047355] CPU: 3 PID: 4072 Comm: a.out Not tainted 4.18.0-rc4+ #51
  [  141.048446] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),BIOS 1.10.2-1 04/01/2014
  [  141.049877] Call Trace:
  [  141.050324]  __dump_stack lib/dump_stack.c:77 [inline]
  [  141.050324]  dump_stack+0x1c9/0x2b4 lib/dump_stack.c:113
  [  141.050950]  ? dump_stack_print_info.cold.2+0x52/0x52 lib/dump_stack.c:60
  [  141.051837]  panic+0x238/0x4e7 kernel/panic.c:184
  [  141.052386]  ? add_taint.cold.5+0x16/0x16 kernel/panic.c:385
  [  141.053101]  ? __warn.cold.8+0x148/0x1ba kernel/panic.c:537
  [  141.053814]  ? __warn.cold.8+0x117/0x1ba kernel/panic.c:530
  [  141.054506]  ? get_callee_stack_depth kernel/bpf/verifier.c:1612 [inline]
  [  141.054506]  ? fixup_call_args kernel/bpf/verifier.c:5587 [inline]
  [  141.054506]  ? bpf_check+0x525e/0x5e60 kernel/bpf/verifier.c:5952
  [  141.055163]  __warn.cold.8+0x163/0x1ba kernel/panic.c:538
  [  141.055820]  ? get_callee_stack_depth kernel/bpf/verifier.c:1612 [inline]
  [  141.055820]  ? fixup_call_args kernel/bpf/verifier.c:5587 [inline]
  [  141.055820]  ? bpf_check+0x525e/0x5e60 kernel/bpf/verifier.c:5952
  [...]

What happens in jit_subprogs() is that kcalloc() for the subprog func
buffer is failing with NULL where we then bail out. Latter is a plain
return -ENOMEM, and this is definitely not okay since earlier in the
loop we are walking all subprogs and temporarily rewrite insn->off to
remember the subprog id as well as insn->imm to temporarily point the
call to __bpf_call_base + 1 for the initial JIT pass. Thus, bailing
out in such state and handing this over to the interpreter is troublesome
since later/subsequent e.g. find_subprog() lookups are based on wrong
insn->imm.

Therefore, once we hit this point, we need to jump to out_free path
where we undo all changes from earlier loop, so that interpreter can
work on unmodified insn->{off,imm}.

Another point is that should find_subprog() fail in jit_subprogs() due
to a verifier bug, then we also should not simply defer the program to
the interpreter since also here we did partial modifications. Instead
we should just bail out entirely and return an error to the user who is
trying to load the program.

Fixes: 1c2a088a66 ("bpf: x64: add JIT support for multi-function programs")
Reported-by: syzbot+7d427828b2ea6e592804@syzkaller.appspotmail.com
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-07-12 14:00:54 -07:00
Okash Khawaja b65f370d06 bpf: btf: Fix bitfield extraction for big endian
When extracting bitfield from a number, btf_int_bits_seq_show() builds
a mask and accesses least significant byte of the number in a way
specific to little-endian. This patch fixes that by checking endianness
of the machine and then shifting left and right the unneeded bits.

Thanks to Martin Lau for the help in navigating potential pitfalls when
dealing with endianess and for the final solution.

Fixes: b00b8daec8 ("bpf: btf: Add pretty print capability for data with BTF type info")
Signed-off-by: Okash Khawaja <osk@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-07-11 22:36:08 +02:00
Toshiaki Makita d8d7218ad8 xdp: XDP_REDIRECT should check IFF_UP and MTU
Otherwise we end up with attempting to send packets from down devices
or to send oversized packets, which may cause unexpected driver/device
behaviour. Generic XDP has already done this check, so reuse the logic
in native XDP.

Fixes: 814abfabef ("xdp: add bpf_redirect helper function")
Signed-off-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-07-07 15:25:35 -07:00
John Fastabend 0ea488ff8d bpf: sockmap, convert bpf_compute_data_pointers to bpf_*_sk_skb
In commit

  'bpf: bpf_compute_data uses incorrect cb structure' (8108a77515)

we added the routine bpf_compute_data_end_sk_skb() to compute the
correct data_end values, but this has since been lost. In kernel
v4.14 this was correct and the above patch was applied in it
entirety. Then when v4.14 was merged into v4.15-rc1 net-next tree
we lost the piece that renamed bpf_compute_data_pointers to the
new function bpf_compute_data_end_sk_skb. This was done here,

e1ea2f9856 ("Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net")

When it conflicted with the following rename patch,

6aaae2b6c4 ("bpf: rename bpf_compute_data_end into bpf_compute_data_pointers")

Finally, after a refactor I thought even the function
bpf_compute_data_end_sk_skb() was no longer needed and it was
erroneously removed.

However, we never reverted the sk_skb_convert_ctx_access() usage of
tcp_skb_cb which had been committed and survived the merge conflict.
Here we fix this by adding back the helper and *_data_end_sk_skb()
usage. Using the bpf_skc_data_end mapping is not correct because it
expects a qdisc_skb_cb object but at the sock layer this is not the
case. Even though it happens to work here because we don't overwrite
any data in-use at the socket layer and the cb structure is cleared
later this has potential to create some subtle issues. But, even
more concretely the filter.c access check uses tcp_skb_cb.

And by some act of chance though,

struct bpf_skb_data_end {
        struct qdisc_skb_cb        qdisc_cb;             /*     0    28 */

        /* XXX 4 bytes hole, try to pack */

        void *                     data_meta;            /*    32     8 */
        void *                     data_end;             /*    40     8 */

        /* size: 48, cachelines: 1, members: 3 */
        /* sum members: 44, holes: 1, sum holes: 4 */
        /* last cacheline: 48 bytes */
};

and then tcp_skb_cb,

struct tcp_skb_cb {
	[...]
                struct {
                        __u32      flags;                /*    24     4 */
                        struct sock * sk_redir;          /*    32     8 */
                        void *     data_end;             /*    40     8 */
                } bpf;                                   /*          24 */
        };

So when we use offset_of() to track down the byte offset we get 40 in
either case and everything continues to work. Fix this mess and use
correct structures its unclear how long this might actually work for
until someone moves the structs around.

Reported-by: Martin KaFai Lau <kafai@fb.com>
Fixes: e1ea2f9856 ("Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net")
Fixes: 6aaae2b6c4 ("bpf: rename bpf_compute_data_end into bpf_compute_data_pointers")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-07-07 15:19:30 -07:00
John Fastabend 7ebc14d507 bpf: sockmap, consume_skb in close path
Currently, when a sock is closed and the bpf_tcp_close() callback is
used we remove memory but do not free the skb. Call consume_skb() if
the skb is attached to the buffer.

Reported-by: syzbot+d464d2c20c717ef5a6a8@syzkaller.appspotmail.com
Fixes: 1aa12bdf1b ("bpf: sockmap, add sock close() hook to remove socks")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-07-07 15:19:30 -07:00
John Fastabend 99ba2b5aba bpf: sockhash, disallow bpf_tcp_close and update in parallel
After latest lock updates there is no longer anything preventing a
close and recvmsg call running in parallel. Additionally, we can
race update with close if we close a socket and simultaneously update
if via the BPF userspace API (note the cgroup ops are already run
with sock_lock held).

To resolve this take sock_lock in close and update paths.

Reported-by: syzbot+b680e42077a0d7c9a0c4@syzkaller.appspotmail.com
Fixes: e9db4ef6bf ("bpf: sockhash fix omitted bucket lock in sock_close")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-07-07 15:19:30 -07:00
John Fastabend 1d1ef005db bpf: sockmap, hash table is RCU so readers do not need locks
This removes locking from readers of RCU hash table. Its not
necessary.

Fixes: 8111038444 ("bpf: sockmap, add hash map support")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-07-07 15:16:58 -07:00
John Fastabend 547b3aa451 bpf: sockmap, error path can not release psock in multi-map case
The current code, in the error path of sock_hash_ctx_update_elem,
checks if the sock has a psock in the user data and if so decrements
the reference count of the psock. However, if the error happens early
in the error path we may have never incremented the psock reference
count and if the psock exists because the sock is in another map then
we may inadvertently decrement the reference count.

Fix this by making the error path only call smap_release_sock if the
error happens after the increment.

Reported-by: syzbot+d464d2c20c717ef5a6a8@syzkaller.appspotmail.com
Fixes: 8111038444 ("bpf: sockmap, add hash map support")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-07-07 15:16:58 -07:00
Mauricio Vasquez B ed2b82c03d bpf: hash map: decrement counter on error
Decrement the number of elements in the map in case the allocation
of a new node fails.

Fixes: 6c90598174 ("bpf: pre-allocate hash map elements")
Signed-off-by: Mauricio Vasquez B <mauricio.vasquez@polito.it>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-07-03 23:26:28 +02:00
Linus Torvalds 4e33d7d479 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Verify netlink attributes properly in nf_queue, from Eric Dumazet.

 2) Need to bump memory lock rlimit for test_sockmap bpf test, from
    Yonghong Song.

 3) Fix VLAN handling in lan78xx driver, from Dave Stevenson.

 4) Fix uninitialized read in nf_log, from Jann Horn.

 5) Fix raw command length parsing in mlx5, from Alex Vesker.

 6) Cleanup loopback RDS connections upon netns deletion, from Sowmini
    Varadhan.

 7) Fix regressions in FIB rule matching during create, from Jason A.
    Donenfeld and Roopa Prabhu.

 8) Fix mpls ether type detection in nfp, from Pieter Jansen van Vuuren.

 9) More bpfilter build fixes/adjustments from Masahiro Yamada.

10) Fix XDP_{TX,REDIRECT} flushing in various drivers, from Jesper
    Dangaard Brouer.

11) fib_tests.sh file permissions were broken, from Shuah Khan.

12) Make sure BH/preemption is disabled in data path of mac80211, from
    Denis Kenzior.

13) Don't ignore nla_parse_nested() return values in nl80211, from
    Johannes berg.

14) Properly account sock objects ot kmemcg, from Shakeel Butt.

15) Adjustments to setting bpf program permissions to read-only, from
    Daniel Borkmann.

16) TCP Fast Open key endianness was broken, it always took on the host
    endiannness. Whoops. Explicitly make it little endian. From Yuching
    Cheng.

17) Fix prefix route setting for link local addresses in ipv6, from
    David Ahern.

18) Potential Spectre v1 in zatm driver, from Gustavo A. R. Silva.

19) Various bpf sockmap fixes, from John Fastabend.

20) Use after free for GRO with ESP, from Sabrina Dubroca.

21) Passing bogus flags to crypto_alloc_shash() in ipv6 SR code, from
    Eric Biggers.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (87 commits)
  qede: Adverstise software timestamp caps when PHC is not available.
  qed: Fix use of incorrect size in memcpy call.
  qed: Fix setting of incorrect eswitch mode.
  qed: Limit msix vectors in kdump kernel to the minimum required count.
  ipvlan: call dev_change_flags when ipvlan mode is reset
  ipv6: sr: fix passing wrong flags to crypto_alloc_shash()
  net: fix use-after-free in GRO with ESP
  tcp: prevent bogus FRTO undos with non-SACK flows
  bpf: sockhash, add release routine
  bpf: sockhash fix omitted bucket lock in sock_close
  bpf: sockmap, fix smap_list_map_remove when psock is in many maps
  bpf: sockmap, fix crash when ipv6 sock is added
  net: fib_rules: bring back rule_exists to match rule during add
  hv_netvsc: split sub-channel setup into async and sync
  net: use dev_change_tx_queue_len() for SIOCSIFTXQLEN
  atm: zatm: Fix potential Spectre v1
  s390/qeth: consistently re-enable device features
  s390/qeth: don't clobber buffer on async TX completion
  s390/qeth: avoid using is_multicast_ether_addr_64bits on (u8 *)[6]
  s390/qeth: fix race when setting MAC address
  ...
2018-07-02 11:18:28 -07:00
Linus Torvalds c350d6d1d7 Add a missing export required by riscv and unicore
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Merge tag 'dma-mapping-4.18-2' of git://git.infradead.org/users/hch/dma-mapping

Pull dma mapping fixlet from Christoph Hellwig:
 "Add a missing export required by riscv and unicore"

* tag 'dma-mapping-4.18-2' of git://git.infradead.org/users/hch/dma-mapping:
  swiotlb: export swiotlb_dma_ops
2018-07-01 10:45:13 -07:00
David S. Miller 271b955e52 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:

====================
pull-request: bpf 2018-07-01

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

The main changes are:

1) A bpf_fib_lookup() helper fix to change the API before freeze to
   return an encoding of the FIB lookup result and return the nexthop
   device index in the params struct (instead of device index as return
   code that we had before), from David.

2) Various BPF JIT fixes to address syzkaller fallout, that is, do not
   reject progs when set_memory_*() fails since it could still be RO.
   Also arm32 JIT was not using bpf_jit_binary_lock_ro() API which was
   an issue, and a memory leak in s390 JIT found during review, from
   Daniel.

3) Multiple fixes for sockmap/hash to address most of the syzkaller
   triggered bugs. Usage with IPv6 was crashing, a GPF in bpf_tcp_close(),
   a missing sock_map_release() routine to hook up to callbacks, and a
   fix for an omitted bucket lock in sock_close(), from John.

4) Two bpftool fixes to remove duplicated error message on program load,
   and another one to close the libbpf object after program load. One
   additional fix for nfp driver's BPF offload to avoid stopping offload
   completely if replace of program failed, from Jakub.

5) Couple of BPF selftest fixes that bail out in some of the test
   scripts if the user does not have the right privileges, from Jeffrin.

6) Fixes in test_bpf for s390 when CONFIG_BPF_JIT_ALWAYS_ON is set
   where we need to set the flag that some of the test cases are expected
   to fail, from Kleber.

7) Fix to detangle BPF_LIRC_MODE2 dependency from CONFIG_CGROUP_BPF
   since it has no relation to it and lirc2 users often have configs
   without cgroups enabled and thus would not be able to use it, from Sean.

8) Fix a selftest failure in sockmap by removing a useless setrlimit()
   call that would set a too low limit where at the same time we are
   already including bpf_rlimit.h that does the job, from Yonghong.

9) Fix BPF selftest config with missing missing NET_SCHED, from Anders.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-01 09:27:44 +09:00
John Fastabend caac76a517 bpf: sockhash, add release routine
Add map_release_uref pointer to hashmap ops. This was dropped when
original sockhash code was ported into bpf-next before initial
commit.

Fixes: 8111038444 ("bpf: sockmap, add hash map support")
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-07-01 01:21:32 +02:00
John Fastabend e9db4ef6bf bpf: sockhash fix omitted bucket lock in sock_close
First the sk_callback_lock() was being used to protect both the
sock callback hooks and the psock->maps list. This got overly
convoluted after the addition of sockhash (in sockmap it made
some sense because masp and callbacks were tightly coupled) so
lets split out a specific lock for maps and only use the callback
lock for its intended purpose. This fixes a couple cases where
we missed using maps lock when it was in fact needed. Also this
makes it easier to follow the code because now we can put the
locking closer to the actual code its serializing.

Next, in sock_hash_delete_elem() the pattern was as follows,

  sock_hash_delete_elem()
     [...]
     spin_lock(bucket_lock)
     l = lookup_elem_raw()
     if (l)
        hlist_del_rcu()
        write_lock(sk_callback_lock)
         .... destroy psock ...
        write_unlock(sk_callback_lock)
     spin_unlock(bucket_lock)

The ordering is necessary because we only know the {p}sock after
dereferencing the hash table which we can't do unless we have the
bucket lock held. Once we have the bucket lock and the psock element
it is deleted from the hashmap to ensure any other path doing a lookup
will fail. Finally, the refcnt is decremented and if zero the psock
is destroyed.

In parallel with the above (or free'ing the map) a tcp close event
may trigger tcp_close(). Which at the moment omits the bucket lock
altogether (oops!) where the flow looks like this,

  bpf_tcp_close()
     [...]
     write_lock(sk_callback_lock)
     for each psock->maps // list of maps this sock is part of
         hlist_del_rcu(ref_hash_node);
         .... destroy psock ...
     write_unlock(sk_callback_lock)

Obviously, and demonstrated by syzbot, this is broken because
we can have multiple threads deleting entries via hlist_del_rcu().

To fix this we might be tempted to wrap the hlist operation in a
bucket lock but that would create a lock inversion problem. In
summary to follow locking rules the psocks maps list needs the
sk_callback_lock (after this patch maps_lock) but we need the bucket
lock to do the hlist_del_rcu.

To resolve the lock inversion problem pop the head of the maps list
repeatedly and remove the reference until no more are left. If a
delete happens in parallel from the BPF API that is OK as well because
it will do a similar action, lookup the lock in the map/hash, delete
it from the map/hash, and dec the refcnt. We check for this case
before doing a destroy on the psock to ensure we don't have two
threads tearing down a psock. The new logic is as follows,

  bpf_tcp_close()
  e = psock_map_pop(psock->maps) // done with map lock
  bucket_lock() // lock hash list bucket
  l = lookup_elem_raw(head, hash, key, key_size);
  if (l) {
     //only get here if elmnt was not already removed
     hlist_del_rcu()
     ... destroy psock...
  }
  bucket_unlock()

And finally for all the above to work add missing locking around  map
operations per above. Then add RCU annotations and use
rcu_dereference/rcu_assign_pointer to manage values relying on RCU so
that the object is not free'd from sock_hash_free() while it is being
referenced in bpf_tcp_close().

Reported-by: syzbot+0ce137753c78f7b6acc1@syzkaller.appspotmail.com
Fixes: 8111038444 ("bpf: sockmap, add hash map support")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-07-01 01:21:32 +02:00
John Fastabend 54fedb42c6 bpf: sockmap, fix smap_list_map_remove when psock is in many maps
If a hashmap is free'd with open socks it removes the reference to
the hash entry from the psock. If that is the last reference to the
psock then it will also be free'd by the reference counting logic.
However the current logic that removes the hash reference from the
list of references is broken. In smap_list_remove() we first check
if the sockmap entry matches and then check if the hashmap entry
matches. But, the sockmap entry sill always match because its NULL in
this case which causes the first entry to be removed from the list.
If this is always the "right" entry (because the user adds/removes
entries in order) then everything is OK but otherwise a subsequent
bpf_tcp_close() may reference a free'd object.

To fix this create two list handlers one for sockmap and one for
sockhash.

Reported-by: syzbot+0ce137753c78f7b6acc1@syzkaller.appspotmail.com
Fixes: 8111038444 ("bpf: sockmap, add hash map support")
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-07-01 01:21:31 +02:00
John Fastabend 9901c5d77e bpf: sockmap, fix crash when ipv6 sock is added
This fixes a crash where we assign tcp_prot to IPv6 sockets instead
of tcpv6_prot.

Previously we overwrote the sk->prot field with tcp_prot even in the
AF_INET6 case. This patch ensures the correct tcp_prot and tcpv6_prot
are used.

Tested with 'netserver -6' and 'netperf -H [IPv6]' as well as
'netperf -H [IPv4]'. The ESTABLISHED check resolves the previously
crashing case here.

Fixes: 174a79ff95 ("bpf: sockmap with sk redirect support")
Reported-by: syzbot+5c063698bdbfac19f363@syzkaller.appspotmail.com
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-07-01 01:21:31 +02:00
Daniel Borkmann 85782e037f bpf: undo prog rejection on read-only lock failure
Partially undo commit 9facc33687 ("bpf: reject any prog that failed
read-only lock") since it caused a regression, that is, syzkaller was
able to manage to cause a panic via fault injection deep in set_memory_ro()
path by letting an allocation fail: In x86's __change_page_attr_set_clr()
it was able to change the attributes of the primary mapping but not in
the alias mapping via cpa_process_alias(), so the second, inner call
to the __change_page_attr() via __change_page_attr_set_clr() had to split
a larger page and failed in the alloc_pages() with the artifically triggered
allocation error which is then propagated down to the call site.

Thus, for set_memory_ro() this means that it returned with an error, but
from debugging a probe_kernel_write() revealed EFAULT on that memory since
the primary mapping succeeded to get changed. Therefore the subsequent
hdr->locked = 0 reset triggered the panic as it was performed on read-only
memory, so call-site assumptions were infact wrong to assume that it would
either succeed /or/ not succeed at all since there's no such rollback in
set_memory_*() calls from partial change of mappings, in other words, we're
left in a state that is "half done". A later undo via set_memory_rw() is
succeeding though due to matching permissions on that part (aka due to the
try_preserve_large_page() succeeding). While reproducing locally with
explicitly triggering this error, the initial splitting only happens on
rare occasions and in real world it would additionally need oom conditions,
but that said, it could partially fail. Therefore, it is definitely wrong
to bail out on set_memory_ro() error and reject the program with the
set_memory_*() semantics we have today. Shouldn't have gone the extra mile
since no other user in tree today infact checks for any set_memory_*()
errors, e.g. neither module_enable_ro() / module_disable_ro() for module
RO/NX handling which is mostly default these days nor kprobes core with
alloc_insn_page() / free_insn_page() as examples that could be invoked long
after bootup and original 314beb9bca ("x86: bpf_jit_comp: secure bpf jit
against spraying attacks") did neither when it got first introduced to BPF
so "improving" with bailing out was clearly not right when set_memory_*()
cannot handle it today.

Kees suggested that if set_memory_*() can fail, we should annotate it with
__must_check, and all callers need to deal with it gracefully given those
set_memory_*() markings aren't "advisory", but they're expected to actually
do what they say. This might be an option worth to move forward in future
but would at the same time require that set_memory_*() calls from supporting
archs are guaranteed to be "atomic" in that they provide rollback if part
of the range fails, once that happened, the transition from RW -> RO could
be made more robust that way, while subsequent RO -> RW transition /must/
continue guaranteeing to always succeed the undo part.

Reported-by: syzbot+a4eb8c7766952a1ca872@syzkaller.appspotmail.com
Reported-by: syzbot+d866d1925855328eac3b@syzkaller.appspotmail.com
Fixes: 9facc33687 ("bpf: reject any prog that failed read-only lock")
Cc: Laura Abbott <labbott@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-06-29 10:47:35 -07:00
Christoph Hellwig 210d0797c9 swiotlb: export swiotlb_dma_ops
For architectures that do not use per-device dma ops we need to export
the dma_map_ops structure returned from get_arch_dma_ops().

Fixes: 10314e09 ("riscv: add swiotlb support")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Andreas Schwab <schwab@suse.de>
2018-06-28 14:00:40 +02:00
Mathieu Malaterre 9331510135 perf/core: Move inline keyword at the beginning of declaration
Fix non-fatal warning triggered during compilation with W=1:

  kernel/events/core.c:6106:1: warning: ‘inline’ is not at beginning of declaration [-Wold-style-declaration]
   static void __always_inline
   ^~~~~~

Signed-off-by: Mathieu Malaterre <malat@debian.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180626202301.20270-1-malat@debian.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-06-27 09:55:58 +02:00
Sean Young fdb5c4531c bpf: fix attach type BPF_LIRC_MODE2 dependency wrt CONFIG_CGROUP_BPF
If the kernel is compiled with CONFIG_CGROUP_BPF not enabled, it is not
possible to attach, detach or query IR BPF programs to /dev/lircN devices,
making them impossible to use. For embedded devices, it should be possible
to use IR decoding without cgroups or CONFIG_CGROUP_BPF enabled.

This change requires some refactoring, since bpf_prog_{attach,detach,query}
functions are now always compiled, but their code paths for cgroups need
moving out. Rather than a #ifdef CONFIG_CGROUP_BPF in kernel/bpf/syscall.c,
moving them to kernel/bpf/cgroup.c and kernel/bpf/sockmap.c does not
require #ifdefs since that is already conditionally compiled.

Fixes: f4364dcfc8 ("media: rc: introduce BPF_PROG_LIRC_MODE2")
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-06-26 11:28:38 +02:00
Linus Torvalds c81b995f00 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Thomas Gleixner:
 "A pile of perf updates:

  Kernel side:

   - Remove an incorrect warning in uprobe_init_insn() when
     insn_get_length() fails. The error return code is handled at the
     call site.

   - Move the inline keyword to the right place in the perf ringbuffer
     code to address a W=1 build warning.

  Tooling:

  perf stat:

   - Fix metric column header display alignment

   - Improve error messages for default attributes, providing better
     output for error in command line.

   - Add --interval-clear option, to provide a 'watch' like printing

  perf script:

   - Show hw-cache events too

  perf c2c:

   - Fix data dependency problem in layout of 'struct c2c_hist_entry'

  Core:

   - Do not blindly assume that 'struct perf_evsel' can be obtained via
     a straight forward container_of() as there are call sites which
     hand in a plain 'struct hist' which is not part of a container.

   - Fix error index in the PMU event parser, so that error messages can
     point to the problematic token"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/core: Move the inline keyword at the beginning of the function declaration
  uprobes/x86: Remove incorrect WARN_ON() in uprobe_init_insn()
  perf script: Show hw-cache events
  perf c2c: Keep struct hist_entry at the end of struct c2c_hist_entry
  perf stat: Add event parsing error handling to add_default_attributes
  perf stat: Allow to specify specific metric column len
  perf stat: Fix metric column header display alignment
  perf stat: Use only color_fprintf call in print_metric_only
  perf stat: Add --interval-clear option
  perf tools: Fix error index for pmu event parser
  perf hists: Reimplement hists__has_callchains()
  perf hists browser gtk: Use hist_entry__has_callchains()
  perf hists: Make hist_entry__has_callchains() work with 'perf c2c'
  perf hists: Save the callchain_size in struct hist_entry
2018-06-24 20:29:15 +08:00
Linus Torvalds 2ce413ec16 Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull rseq fixes from Thomas Gleixer:
 "A pile of rseq related fixups:

   - Prevent infinite recursion when delivering SIGSEGV

   - Remove the abort of rseq critical section on fork() as syscalls
     inside rseq critical sections are explicitely forbidden. So no
     point in doing the abort on the child.

   - Align the rseq structure on 32 bytes in the ARM selftest code.

   - Fix file permissions of the test script"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  rseq: Avoid infinite recursion when delivering SIGSEGV
  rseq/cleanup: Do not abort rseq c.s. in child on fork()
  rseq/selftests/arm: Align 'struct rseq_cs' on 32 bytes
  rseq/selftests: Make run_param_test.sh executable
2018-06-24 20:18:19 +08:00
Linus Torvalds 2da2ca24a3 Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking fixes from Thomas Gleixner:
 "A set of fixes and updates for the locking code:

   - Prevent lockdep from updating irq state within its own code and
     thereby confusing itself.

   - Buid fix for older GCCs which mistreat anonymous unions

   - Add a missing lockdep annotation in down_read_non_onwer() which
     causes up_read_non_owner() to emit a lockdep splat

   - Remove the custom alpha dec_and_lock() implementation which is
     incorrect in terms of ordering and use the generic one.

  The remaining two commits are not strictly fixes. They provide irqsave
  variants of atomic_dec_and_lock() and refcount_dec_and_lock(). These
  are required to merge the relevant updates and cleanups into different
  maintainer trees for 4.19, so routing them into mainline without
  actual users is the sanest approach.

  They should have been in -rc1, but last weekend I took the liberty to
  just avoid computers in order to regain some mental sanity"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/qspinlock: Fix build for anonymous union in older GCC compilers
  locking/lockdep: Do not record IRQ state within lockdep code
  locking/rwsem: Fix up_read_non_owner() warning with DEBUG_RWSEMS
  locking/refcounts: Implement refcount_dec_and_lock_irqsave()
  atomic: Add irqsave variant of atomic_dec_and_lock()
  alpha: Remove custom dec_and_lock() implementation
2018-06-24 19:36:16 +08:00
Linus Torvalds 6242258b6b Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fixes from Thomas Gleixner:
 "A small set of fixes for time(r) related issues:

   - Fix a long standing conversion issue in jiffies_to_msecs() for odd
     HZ values like 1024 or 1200 which resulted in returning 0 for small
     jiffies values due to rounding down.

   - Use the proper CONFIG symbol in the new Y2038 safe compat code for
     posix-timers. Not yet a visible breakage, but this will immediately
     trigger when the architecture support for the new interfaces is
     merged.

   - Return an error code in the STM32 clocksource driver on failure
     instead of success.

   - Remove the redundant and stale irq disabled check in the posix cpu
     timer code. The check is at the wrong place anyway and lockdep
     already covers it via the sighand lock locking coverage"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  time: Make sure jiffies_to_msecs() preserves non-zero time periods
  posix-timers: Fix nanosleep_copyout() for CONFIG_COMPAT_32BIT_TIME
  clocksource/drivers/stm32: Fix error return code
  posix-cpu-timers: Remove lockdep_assert_irqs_disabled()
2018-06-24 19:16:42 +08:00
Linus Torvalds 78fea6334f Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fixes from Thomas Gleixner:
 "A set of fixes mostly for the ARM/GIC world:

   - Fix the MSI affinity handling in the ls-scfg irq chip driver so it
     updates and uses the effective affinity mask correctly

   - Prevent binding LPIs to offline CPUs and respect the Cavium erratum
     which requires that LPIs which belong to an offline NUMA node are
     not bound to a CPU on a different NUMA node.

   - Free only the amount of allocated interrupts in the GIC-V2M driver
     instead of trying to free log2(nrirqs).

   - Prevent emitting SYNC and VSYNC targetting non existing interrupt
     collections in the GIC-V3 ITS driver

   - Ensure that the GIV-V3 interrupt redistributor is correctly
     reprogrammed on CPU hotplug

   - Remove a stale unused helper function"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqdesc: Delete irq_desc_get_msi_desc()
  irqchip/gic-v3-its: Fix reprogramming of redistributors on CPU hotplug
  irqchip/gic-v3-its: Only emit VSYNC if targetting a valid collection
  irqchip/gic-v3-its: Only emit SYNC if targetting a valid collection
  irqchip/gic-v3-its: Don't bind LPI to unavailable NUMA node
  irqchip/gic-v2m: Fix SPI release on error path
  irqchip/ls-scfg-msi: Fix MSI affinity handling
  genirq/debugfs: Add missing IRQCHIP_SUPPORTS_LEVEL_MSI debug
2018-06-24 19:01:18 +08:00
Linus Torvalds 81f9c4e417 This contains a few fixes and a clean up.
- A bad merge caused an "endif" to go in the wrong place in
      scripts/Makefile.build
  - Softirq tracing fix for tracing that corrupts lockdep and causes a false
      splat
  - Histogram documentation typo fixes
  - Fix a bad memory reference when passing in no filter to the filter code
  - Simplify code by using the swap macro instead of open coding the swap
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Merge tag 'trace-v4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "This contains a few fixes and a clean up.

   - a bad merge caused an "endif" to go in the wrong place in
     scripts/Makefile.build

   - softirq tracing fix for tracing that corrupts lockdep and causes a
     false splat

   - histogram documentation typo fixes

   - fix a bad memory reference when passing in no filter to the filter
     code

   - simplify code by using the swap macro instead of open coding the
     swap"

* tag 'trace-v4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Fix SKIP_STACK_VALIDATION=1 build due to bad merge with -mrecord-mcount
  tracing: Fix some errors in histogram documentation
  tracing: Use swap macro in update_max_tr
  softirq: Reorder trace_softirqs_on to prevent lockdep splat
  tracing: Check for no filter when processing event filters
2018-06-24 06:23:28 +08:00
Will Deacon 784e0300fe rseq: Avoid infinite recursion when delivering SIGSEGV
When delivering a signal to a task that is using rseq, we call into
__rseq_handle_notify_resume() so that the registers pushed in the
sigframe are updated to reflect the state of the restartable sequence
(for example, ensuring that the signal returns to the abort handler if
necessary).

However, if the rseq management fails due to an unrecoverable fault when
accessing userspace or certain combinations of RSEQ_CS_* flags, then we
will attempt to deliver a SIGSEGV. This has the potential for infinite
recursion if the rseq code continuously fails on signal delivery.

Avoid this problem by using force_sigsegv() instead of force_sig(), which
is explicitly designed to reset the SEGV handler to SIG_DFL in the case
of a recursive fault. In doing so, remove rseq_signal_deliver() from the
internal rseq API and have an optional struct ksignal * parameter to
rseq_handle_notify_resume() instead.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: peterz@infradead.org
Cc: paulmck@linux.vnet.ibm.com
Cc: boqun.feng@gmail.com
Link: https://lkml.kernel.org/r/1529664307-983-1-git-send-email-will.deacon@arm.com
2018-06-22 19:04:22 +02:00
Geert Uytterhoeven abcbcb80cd time: Make sure jiffies_to_msecs() preserves non-zero time periods
For the common cases where 1000 is a multiple of HZ, or HZ is a multiple of
1000, jiffies_to_msecs() never returns zero when passed a non-zero time
period.

However, if HZ > 1000 and not an integer multiple of 1000 (e.g. 1024 or
1200, as used on alpha and DECstation), jiffies_to_msecs() may return zero
for small non-zero time periods.  This may break code that relies on
receiving back a non-zero value.

jiffies_to_usecs() does not need such a fix: one jiffy can only be less
than one µs if HZ > 1000000, and such large values of HZ are already
rejected at build time, twice:

  - include/linux/jiffies.h does #error if HZ >= 12288,
  - kernel/time/time.c has BUILD_BUG_ON(HZ > USEC_PER_SEC).

Broken since forever.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: linux-alpha@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180622143357.7495-1-geert@linux-m68k.org
2018-06-22 17:48:36 +02:00
Marc Zyngier 72a8edc2d9 genirq/debugfs: Add missing IRQCHIP_SUPPORTS_LEVEL_MSI debug
Debug is missing the IRQCHIP_SUPPORTS_LEVEL_MSI debug entry, making debugfs
slightly less useful.

Take this opportunity to also add a missing comment in the definition of
IRQCHIP_SUPPORTS_LEVEL_MSI.

Fixes: 6988e0e0d2 ("genirq/msi: Limit level-triggered MSI to platform devices")
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: Yang Yingliang <yangyingliang@huawei.com>
Cc: Sumit Garg <sumit.garg@linaro.org>
Link: https://lkml.kernel.org/r/20180622095254.5906-2-marc.zyngier@arm.com
2018-06-22 14:22:00 +02:00
Mathieu Malaterre 57d6a7938a perf/core: Move the inline keyword at the beginning of the function declaration
When building perf with W=1 the following warning triggers:

  CC      kernel/events/ring_buffer.o
  kernel/events/ring_buffer.c:105:1: warning: ‘inline’ is not at beginning of declaration [-Wold-style-declaration]
   static bool __always_inline
   ^~~~~~
  ...

Move the inline keyword to the beginning of the function declaration.

Signed-off-by: Mathieu Malaterre <malat@debian.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: trival@kernel.org
Link: http://lkml.kernel.org/r/20180308202856.9378-1-malat@debian.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-06-22 11:07:47 +02:00
Gustavo A. R. Silva 08ae88f810 tracing: Use swap macro in update_max_tr
Make use of the swap macro and remove unnecessary variable _buf_.
This makes the code easier to read and maintain. Also, reduces the
stack usage.

This code was detected with the help of Coccinelle.

Link: http://lkml.kernel.org/r/20180209175316.GA18720@embeddedgus

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-06-21 15:12:43 -04:00
Joel Fernandes (Google) 1a63dcd876 softirq: Reorder trace_softirqs_on to prevent lockdep splat
I'm able to reproduce a lockdep splat with config options:
CONFIG_PROVE_LOCKING=y,
CONFIG_DEBUG_LOCK_ALLOC=y and
CONFIG_PREEMPTIRQ_EVENTS=y

$ echo 1 > /d/tracing/events/preemptirq/preempt_enable/enable

[   26.112609] DEBUG_LOCKS_WARN_ON(current->softirqs_enabled)
[   26.112636] WARNING: CPU: 0 PID: 118 at kernel/locking/lockdep.c:3854
[...]
[   26.144229] Call Trace:
[   26.144926]  <IRQ>
[   26.145506]  lock_acquire+0x55/0x1b0
[   26.146499]  ? __do_softirq+0x46f/0x4d9
[   26.147571]  ? __do_softirq+0x46f/0x4d9
[   26.148646]  trace_preempt_on+0x8f/0x240
[   26.149744]  ? trace_preempt_on+0x4d/0x240
[   26.150862]  ? __do_softirq+0x46f/0x4d9
[   26.151930]  preempt_count_sub+0x18a/0x1a0
[   26.152985]  __do_softirq+0x46f/0x4d9
[   26.153937]  irq_exit+0x68/0xe0
[   26.154755]  smp_apic_timer_interrupt+0x271/0x280
[   26.156056]  apic_timer_interrupt+0xf/0x20
[   26.157105]  </IRQ>

The issue was this:

preempt_count = 1 << SOFTIRQ_SHIFT

	__local_bh_enable(cnt = 1 << SOFTIRQ_SHIFT) {
		if (softirq_count() == (cnt && SOFTIRQ_MASK)) {
			trace_softirqs_on() {
				current->softirqs_enabled = 1;
			}
		}
		preempt_count_sub(cnt) {
			trace_preempt_on() {
				tracepoint() {
					rcu_read_lock_sched() {
						// jumps into lockdep

Where preempt_count still has softirqs disabled, but
current->softirqs_enabled is true, and we get a splat.

Link: http://lkml.kernel.org/r/20180607201143.247775-1-joel@joelfernandes.org

Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Tom Zanussi <tom.zanussi@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Thomas Glexiner <tglx@linutronix.de>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Todd Kjos <tkjos@google.com>
Cc: Erick Reyes <erickreyes@google.com>
Cc: Julia Cartwright <julia@ni.com>
Cc: Byungchul Park <byungchul.park@lge.com>
Cc: stable@vger.kernel.org
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Fixes: d59158162e ("tracing: Add support for preempt and irq enable/disable events")
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-06-21 15:12:43 -04:00
Steven Rostedt (VMware) 70303420b5 tracing: Check for no filter when processing event filters
The syzkaller detected a out-of-bounds issue with the events filter code,
specifically here:

	prog[N].pred = NULL;					/* #13 */
	prog[N].target = 1;		/* TRUE */
	prog[N+1].pred = NULL;
	prog[N+1].target = 0;		/* FALSE */
->	prog[N-1].target = N;
	prog[N-1].when_to_branch = false;

As that's the first reference to a "N-1" index, it appears that the code got
here with N = 0, which means the filter parser found no filter to parse
(which shouldn't ever happen, but apparently it did).

Add a new error to the parsing code that will check to make sure that N is
not zero before going into this part of the code. If N = 0, then -EINVAL is
returned, and a error message is added to the filter.

Cc: stable@vger.kernel.org
Fixes: 80765597bc ("tracing: Rewrite filter logic to be simpler and faster")
Reported-by: air icy <icytxw@gmail.com>
bugzilla url: https://bugzilla.kernel.org/show_bug.cgi?id=200019
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-06-21 15:12:42 -04:00
Steven Rostedt (VMware) fcc784be83 locking/lockdep: Do not record IRQ state within lockdep code
While debugging where things were going wrong with mapping
enabling/disabling interrupts with the lockdep state and actual real
enabling and disabling interrupts, I had to silent the IRQ
disabling/enabling in debug_check_no_locks_freed() because it was
always showing up as it was called before the splat was.

Use raw_local_irq_save/restore() for not only debug_check_no_locks_freed()
but for all internal lockdep functions, as they hide useful information
about where interrupts were used incorrectly last.

Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Link: https://lkml.kernel.org/lkml/20180404140630.3f4f4c7a@gandalf.local.home
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-06-21 18:19:01 +02:00
Linus Torvalds d8894a08d9 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Fix crash on bpf_prog_load() errors, from Daniel Borkmann.

 2) Fix ATM VCC memory accounting, from David Woodhouse.

 3) fib6_info objects need RCU freeing, from Eric Dumazet.

 4) Fix SO_BINDTODEVICE handling for TCP sockets, from David Ahern.

 5) Fix clobbered error code in enic_open() failure path, from
    Govindarajulu Varadarajan.

 6) Propagate dev_get_valid_name() error returns properly, from Li
    RongQing.

 7) Fix suspend/resume in davinci_emac driver, from Bartosz Golaszewski.

 8) Various act_ife fixes (recursive locking, IDR leaks, etc.) from
    Davide Caratti.

 9) Fix buggy checksum handling in sungem driver, from Eric Dumazet.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (40 commits)
  ip: limit use of gso_size to udp
  stmmac: fix DMA channel hang in half-duplex mode
  net: stmmac: socfpga: add additional ocp reset line for Stratix10
  net: sungem: fix rx checksum support
  bpfilter: ignore binary files
  bpfilter: fix build error
  net/usb/drivers: Remove useless hrtimer_active check
  net/sched: act_ife: preserve the action control in case of error
  net/sched: act_ife: fix recursive lock and idr leak
  net: ethernet: fix suspend/resume in davinci_emac
  net: propagate dev_get_valid_name return code
  enic: do not overwrite error code
  net/tcp: Fix socket lookups with SO_BINDTODEVICE
  ptp: replace getnstimeofday64() with ktime_get_real_ts64()
  net/ipv6: respect rcu grace period before freeing fib6_info
  net: net_failover: fix typo in net_failover_slave_register()
  ipvlan: use ETH_MAX_MTU as max mtu
  net: hamradio: use eth_broadcast_addr
  enic: initialize enic->rfs_h.lock in enic_probe
  MAINTAINERS: Add Sam as the maintainer for NCSI
  ...
2018-06-21 07:13:42 +09:00
Waiman Long 03eeafdd9a locking/rwsem: Fix up_read_non_owner() warning with DEBUG_RWSEMS
It was found that the use of up_read_non_owner() in NFS was causing
the following warning when DEBUG_RWSEMS was configured.

  DEBUG_LOCKS_WARN_ON(sem->owner != ((struct task_struct *)(1UL << 0)))

Looking into the rwsem.c file, it was discovered that the corresponding
down_read_non_owner() function was not setting the owner field properly.
This is fixed now, and the warning should be gone.

Fixes: 5149cbac42 ("locking/rwsem: Add DEBUG_RWSEMS to look for lock/unlock mismatches")
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Gavin Schenk <g.schenk@eckelmann.de>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linux-nfs@vger.kernel.org
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/1527168398-4291-1-git-send-email-longman@redhat.com
2018-06-20 11:29:23 +02:00
Linus Torvalds 6d90eb7ba3 Move all the dma-mapping code to kernel/dma
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Merge tag 'dma-rename-4.18' of git://git.infradead.org/users/hch/dma-mapping

Pull dma-mapping rename from Christoph Hellwig:
 "Move all the dma-mapping code to kernel/dma and lose their dma-*
  prefixes"

* tag 'dma-rename-4.18' of git://git.infradead.org/users/hch/dma-mapping:
  dma-mapping: move all DMA mapping code to kernel/dma
  dma-mapping: use obj-y instead of lib-y for generic dma ops
2018-06-20 16:30:01 +09:00
Arnd Bergmann 0fe2795516 posix-timers: Fix nanosleep_copyout() for CONFIG_COMPAT_32BIT_TIME
Commit b5793b0d92 added support for building the nanosleep compat system
call on 32-bit architectures, but missed one change in nanosleep_copyout(),
which would trigger a BUG() as soon as any architecture is switched over to
use it.

Use the proper config symbol to enable the code path.

Fixes: Commit b5793b0d92 ("posix-timers: Make compat syscalls depend on CONFIG_COMPAT_32BIT_TIME")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: y2038@lists.linaro.org
Cc: Anna-Maria Gleixner <anna-maria@linutronix.de>
Cc: Deepa Dinamani <deepa.kernel@gmail.com>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Link: https://lkml.kernel.org/r/20180618140811.2998503-1-arnd@arndb.de
2018-06-19 09:23:19 +02:00
David S. Miller 0841d98641 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:

====================
pull-request: bpf 2018-06-16

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

The main changes are:

1) Fix a panic in devmap handling in generic XDP where return type
   of __devmap_lookup_elem() got changed recently but generic XDP
   code missed the related update, from Toshiaki.

2) Fix a freeze when BPF progs are loaded that include BPF to BPF
   calls when JIT is enabled where we would later bail out via error
   path w/o dropping kallsyms, and another one to silence syzkaller
   splats from locking prog read-only, from Daniel.

3) Fix a bug in test_offloads.py BPF selftest which must not assume
   that the underlying system have no BPF progs loaded prior to test,
   and one in bpftool to fix accuracy of program load time, from Jakub.

4) Fix a bug in bpftool's probe for availability of the bpf(2)
   BPF_TASK_FD_QUERY subcommand, from Yonghong.

5) Fix a regression in AF_XDP's XDP_SKB receive path where queue
   id check got erroneously removed, from Björn.

6) Fix missing state cleanup in BPF's xfrm tunnel test, from William.

7) Check tunnel type more accurately in BPF's tunnel collect metadata
   kselftest, from Jian.

8) Fix missing Kconfig fragments for BPF kselftests, from Anders.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-17 07:54:24 +09:00
Linus Torvalds 5e7b9212a4 Solve a series of broken links for files under Documentation:
- can.rst: fix a footnote reference;
 - crypto_engine.rst: Fix two parsing warnings;
 - Fix a lot of broken references to Documentation/*;
 - Improves the scripts/documentation-file-ref-check script,
   in order to help detecting/fixing broken references,
   preventing false-positives.
 
 After this patch series, only 33 broken references to doc files are
 detected by scripts/documentation-file-ref-check.
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Merge tag 'docs-broken-links' of git://linuxtv.org/mchehab/experimental

Pull documentation fixes from Mauro Carvalho Chehab:
 "This solves a series of broken links for files under Documentation,
  and improves a script meant to detect such broken links (see
  scripts/documentation-file-ref-check).

  The changes on this series are:

   - can.rst: fix a footnote reference;

   - crypto_engine.rst: Fix two parsing warnings;

   - Fix a lot of broken references to Documentation/*;

   - improve the scripts/documentation-file-ref-check script, in order
     to help detecting/fixing broken references, preventing
     false-positives.

  After this patch series, only 33 broken references to doc files are
  detected by scripts/documentation-file-ref-check"

* tag 'docs-broken-links' of git://linuxtv.org/mchehab/experimental: (26 commits)
  fix a series of Documentation/ broken file name references
  Documentation: rstFlatTable.py: fix a broken reference
  ABI: sysfs-devices-system-cpu: remove a broken reference
  devicetree: fix a series of wrong file references
  devicetree: fix name of pinctrl-bindings.txt
  devicetree: fix some bindings file names
  MAINTAINERS: fix location of DT npcm files
  MAINTAINERS: fix location of some display DT bindings
  kernel-parameters.txt: fix pointers to sound parameters
  bindings: nvmem/zii: Fix location of nvmem.txt
  docs: Fix more broken references
  scripts/documentation-file-ref-check: check tools/*/Documentation
  scripts/documentation-file-ref-check: get rid of false-positives
  scripts/documentation-file-ref-check: hint: dash or underline
  scripts/documentation-file-ref-check: add a fix logic for DT
  scripts/documentation-file-ref-check: accept more wildcards at filenames
  scripts/documentation-file-ref-check: fix help message
  media: max2175: fix location of driver's companion documentation
  media: v4l: fix broken video4linux docs locations
  media: dvb: point to the location of the old README.dvb-usb file
  ...
2018-06-17 05:25:18 +09:00
Linus Torvalds dbb2816fc7 \n
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Merge tag 'fsnotify_for_v4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs

Pull fsnotify updates from Jan Kara:
 "fsnotify cleanups unifying handling of different watch types.

  This is the shortened fsnotify series from Amir with the last five
  patches pulled out. Amir has modified those patches to not change
  struct inode but obviously it's too late for those to go into this
  merge window"

* tag 'fsnotify_for_v4.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  fsnotify: add fsnotify_add_inode_mark() wrappers
  fanotify: generalize fanotify_should_send_event()
  fsnotify: generalize send_to_group()
  fsnotify: generalize iteration of marks by object type
  fsnotify: introduce marks iteration helpers
  fsnotify: remove redundant arguments to handle_event()
  fsnotify: use type id to identify connector object type
2018-06-17 05:06:18 +09:00
Linus Torvalds 9215310cf1 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Various netfilter fixlets from Pablo and the netfilter team.

 2) Fix regression in IPVS caused by lack of PMTU exceptions on local
    routes in ipv6, from Julian Anastasov.

 3) Check pskb_trim_rcsum for failure in DSA, from Zhouyang Jia.

 4) Don't crash on poll in TLS, from Daniel Borkmann.

 5) Revert SO_REUSE{ADDR,PORT} change, it regresses various things
    including Avahi mDNS. From Bart Van Assche.

 6) Missing of_node_put in qcom/emac driver, from Yue Haibing.

 7) We lack checking of the TCP checking in one special case during SYN
    receive, from Frank van der Linden.

 8) Fix module init error paths of mac80211 hwsim, from Johannes Berg.

 9) Handle 802.1ad properly in stmmac driver, from Elad Nachman.

10) Must grab HW caps before doing quirk checks in stmmac driver, from
    Jose Abreu.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (81 commits)
  net: stmmac: Run HWIF Quirks after getting HW caps
  neighbour: skip NTF_EXT_LEARNED entries during forced gc
  net: cxgb3: add error handling for sysfs_create_group
  tls: fix waitall behavior in tls_sw_recvmsg
  tls: fix use-after-free in tls_push_record
  l2tp: filter out non-PPP sessions in pppol2tp_tunnel_ioctl()
  l2tp: reject creation of non-PPP sessions on L2TPv2 tunnels
  mlxsw: spectrum_switchdev: Fix port_vlan refcounting
  mlxsw: spectrum_router: Align with new route replace logic
  mlxsw: spectrum_router: Allow appending to dev-only routes
  ipv6: Only emit append events for appended routes
  stmmac: added support for 802.1ad vlan stripping
  cfg80211: fix rcu in cfg80211_unregister_wdev
  mac80211: Move up init of TXQs
  mac80211_hwsim: fix module init error paths
  cfg80211: initialize sinfo in cfg80211_get_station
  nl80211: fix some kernel doc tag mistakes
  hv_netvsc: Fix the variable sizes in ipsecv2 and rsc offload
  rds: avoid unenecessary cong_update in loop transport
  l2tp: clean up stale tunnel or session in pppol2tp_connect's error path
  ...
2018-06-16 07:39:34 +09:00
Linus Torvalds de7f01c22a Modules updates for v4.18
Summary of modules changes for the 4.18 merge window:
 
 - Minor code cleanup and also allow sig_enforce param to be shown in
   sysfs with CONFIG_MODULE_SIG_FORCE
 
 Signed-off-by: Jessica Yu <jeyu@kernel.org>
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Merge tag 'modules-for-v4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux

Pull module updates from Jessica Yu:
 "Minor code cleanup and also allow sig_enforce param to be shown in
  sysfs with CONFIG_MODULE_SIG_FORCE"

* tag 'modules-for-v4.18' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
  module: Allow to always show the status of modsign
  module: Do not access sig_enforce directly
2018-06-16 07:36:39 +09:00
Toshiaki Makita 6d5fc19579 xdp: Fix handling of devmap in generic XDP
Commit 67f29e07e1 ("bpf: devmap introduce dev_map_enqueue") changed
the return value type of __devmap_lookup_elem() from struct net_device *
to struct bpf_dtab_netdev * but forgot to modify generic XDP code
accordingly.

Thus generic XDP incorrectly used struct bpf_dtab_netdev where struct
net_device is expected, then skb->dev was set to invalid value.

v2:
- Fix compiler warning without CONFIG_BPF_SYSCALL.

Fixes: 67f29e07e1 ("bpf: devmap introduce dev_map_enqueue")
Signed-off-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-06-15 23:47:15 +02:00
Mauro Carvalho Chehab 44348e8ac1 fix a series of Documentation/ broken file name references
As files move around, their previous links break. Fix the
references for them.

Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Jonathan Corbet <corbet@lwn.net>
2018-06-15 18:10:01 -03:00
Mauro Carvalho Chehab 5fb94e9ca3 docs: Fix some broken references
As we move stuff around, some doc references are broken. Fix some of
them via this script:
	./scripts/documentation-file-ref-check --fix

Manually checked if the produced result is valid, removing a few
false-positives.

Acked-by: Takashi Iwai <tiwai@suse.de>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Acked-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Acked-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Coly Li <colyli@suse.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Jonathan Corbet <corbet@lwn.net>
2018-06-15 18:10:01 -03:00
Daniel Borkmann 9facc33687 bpf: reject any prog that failed read-only lock
We currently lock any JITed image as read-only via bpf_jit_binary_lock_ro()
as well as the BPF image as read-only through bpf_prog_lock_ro(). In
the case any of these would fail we throw a WARN_ON_ONCE() in order to
yell loudly to the log. Perhaps, to some extend, this may be comparable
to an allocation where __GFP_NOWARN is explicitly not set.

Added via 65869a47f3 ("bpf: improve read-only handling"), this behavior
is slightly different compared to any of the other in-kernel set_memory_ro()
users who do not check the return code of set_memory_ro() and friends /at
all/ (e.g. in the case of module_enable_ro() / module_disable_ro()). Given
in BPF this is mandatory hardening step, we want to know whether there
are any issues that would leave both BPF data writable. So it happens
that syzkaller enabled fault injection and it triggered memory allocation
failure deep inside x86's change_page_attr_set_clr() which was triggered
from set_memory_ro().

Now, there are two options: i) leaving everything as is, and ii) reworking
the image locking code in order to have a final checkpoint out of the
central bpf_prog_select_runtime() which probes whether any of the calls
during prog setup weren't successful, and then bailing out with an error.
Option ii) is a better approach since this additional paranoia avoids
altogether leaving any potential W+X pages from BPF side in the system.
Therefore, lets be strict about it, and reject programs in such unlikely
occasion. While testing I noticed also that one bpf_prog_lock_ro()
call was missing on the outer dummy prog in case of calls, e.g. in the
destructor we call bpf_prog_free_deferred() on the main prog where we
try to bpf_prog_unlock_free() the program, and since we go via
bpf_prog_select_runtime() do that as well.

Reported-by: syzbot+3b889862e65a98317058@syzkaller.appspotmail.com
Reported-by: syzbot+9e762b52dd17e616a7a5@syzkaller.appspotmail.com
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-06-15 11:14:25 -07:00
Daniel Borkmann 7d1982b4e3 bpf: fix panic in prog load calls cleanup
While testing I found that when hitting error path in bpf_prog_load()
where we jump to free_used_maps and prog contained BPF to BPF calls
that were JITed earlier, then we never clean up the bpf_prog_kallsyms_add()
done under jit_subprogs(). Add proper API to make BPF kallsyms deletion
more clear and fix that.

Fixes: 1c2a088a66 ("bpf: x64: add JIT support for multi-function programs")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-06-15 11:14:25 -07:00
Linus Torvalds b5d903c2d6 Merge branch 'akpm' (patches from Andrew)
Merge more updates from Andrew Morton:

 - MM remainders

 - various misc things

 - kcov updates

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (27 commits)
  lib/test_printf.c: call wait_for_random_bytes() before plain %p tests
  hexagon: drop the unused variable zero_page_mask
  hexagon: fix printk format warning in setup.c
  mm: fix oom_kill event handling
  treewide: use PHYS_ADDR_MAX to avoid type casting ULLONG_MAX
  mm: use octal not symbolic permissions
  ipc: use new return type vm_fault_t
  sysvipc/sem: mitigate semnum index against spectre v1
  fault-injection: reorder config entries
  arm: port KCOV to arm
  sched/core / kcov: avoid kcov_area during task switch
  kcov: prefault the kcov_area
  kcov: ensure irq code sees a valid area
  kernel/relay.c: change return type to vm_fault_t
  exofs: avoid VLA in structures
  coredump: fix spam with zero VMA process
  fat: use fat_fs_error() instead of BUG_ON() in __fat_get_block()
  proc: skip branch in /proc/*/* lookup
  mremap: remove LATENCY_LIMIT from mremap to reduce the number of TLB shootdowns
  mm/memblock: add missing include <linux/bootmem.h>
  ...
2018-06-15 08:51:42 +09:00
Mark Rutland 0ed557aa81 sched/core / kcov: avoid kcov_area during task switch
During a context switch, we first switch_mm() to the next task's mm,
then switch_to() that new task.  This means that vmalloc'd regions which
had previously been faulted in can transiently disappear in the context
of the prev task.

Functions instrumented by KCOV may try to access a vmalloc'd kcov_area
during this window, and as the fault handling code is instrumented, this
results in a recursive fault.

We must avoid accessing any kcov_area during this window.  We can do so
with a new flag in kcov_mode, set prior to switching the mm, and cleared
once the new task is live.  Since task_struct::kcov_mode isn't always a
specific enum kcov_mode value, this is made an unsigned int.

The manipulation is hidden behind kcov_{prepare,finish}_switch() helpers,
which are empty for !CONFIG_KCOV kernels.

The code uses macros because I can't use static inline functions without a
circular include dependency between <linux/sched.h> and <linux/kcov.h>,
since the definition of task_struct uses things defined in <linux/kcov.h>

Link: http://lkml.kernel.org/r/20180504135535.53744-4-mark.rutland@arm.com
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-06-15 07:55:24 +09:00