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  1. 06 7月, 2016 2 次提交
  3. 05 7月, 2016 5 次提交
  5. 03 7月, 2016 2 次提交
  7. 02 7月, 2016 3 次提交
    • M
      cgroup: Add cgroup_get_from_fd · 1f3fe7eb
      由 Martin KaFai Lau 提交于 
      Add a helper function to get a cgroup2 from a fd.  It will be
stored in a bpf array (BPF_MAP_TYPE_CGROUP_ARRAY) which will
be introduced in the later patch.
Signed-off-by: NMartin KaFai Lau <kafai@fb.com>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Tejun Heo <tj@kernel.org>
Acked-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      1f3fe7eb
    • D
      bpf: refactor bpf_prog_get and type check into helper · 113214be
      由 Daniel Borkmann 提交于 
      Since bpf_prog_get() and program type check is used in a couple of places,
refactor this into a small helper function that we can make use of. Since
the non RO prog->aux part is not used in performance critical paths and a
program destruction via RCU is rather very unlikley when doing the put, we
shouldn't have an issue just doing the bpf_prog_get() + prog->type != type
check, but actually not taking the ref at all (due to being in fdget() /
fdput() section of the bpf fd) is even cleaner and makes the diff smaller
as well, so just go for that. Callsites are changed to make use of the new
helper where possible.
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      113214be
    • D
      bpf: generally move prog destruction to RCU deferral · 1aacde3d
      由 Daniel Borkmann 提交于 
      Jann Horn reported following analysis that could potentially result
in a very hard to trigger (if not impossible) UAF race, to quote his
event timeline:

 - Set up a process with threads T1, T2 and T3
 - Let T1 set up a socket filter F1 that invokes another filter F2
   through a BPF map [tail call]
 - Let T1 trigger the socket filter via a unix domain socket write,
   don't wait for completion
 - Let T2 call PERF_EVENT_IOC_SET_BPF with F2, don't wait for completion
 - Now T2 should be behind bpf_prog_get(), but before bpf_prog_put()
 - Let T3 close the file descriptor for F2, dropping the reference
   count of F2 to 2
 - At this point, T1 should have looked up F2 from the map, but not
   finished executing it
 - Let T3 remove F2 from the BPF map, dropping the reference count of
   F2 to 1
 - Now T2 should call bpf_prog_put() (wrong BPF program type), dropping
   the reference count of F2 to 0 and scheduling bpf_prog_free_deferred()
   via schedule_work()
 - At this point, the BPF program could be freed
 - BPF execution is still running in a freed BPF program

While at PERF_EVENT_IOC_SET_BPF time it's only guaranteed that the perf
event fd we're doing the syscall on doesn't disappear from underneath us
for whole syscall time, it may not be the case for the bpf fd used as
an argument only after we did the put. It needs to be a valid fd pointing
to a BPF program at the time of the call to make the bpf_prog_get() and
while T2 gets preempted, F2 must have dropped reference to 1 on the other
CPU. The fput() from the close() in T3 should also add additionally delay
to the reference drop via exit_task_work() when bpf_prog_release() gets
called as well as scheduling bpf_prog_free_deferred().

That said, it makes nevertheless sense to move the BPF prog destruction
generally after RCU grace period to guarantee that such scenario above,
but also others as recently fixed in ceb56070 ("bpf, perf: delay release
of BPF prog after grace period") with regards to tail calls won't happen.
Integrating bpf_prog_free_deferred() directly into the RCU callback is
not allowed since the invocation might happen from either softirq or
process context, so we're not permitted to block. Reviewing all bpf_prog_put()
invocations from eBPF side (note, cBPF -> eBPF progs don't use this for
their destruction) with call_rcu() look good to me.

Since we don't know whether at the time of attaching the program, we're
already part of a tail call map, we need to use RCU variant. However, due
to this, there won't be severely more stress on the RCU callback queue:
situations with above bpf_prog_get() and bpf_prog_put() combo in practice
normally won't lead to releases, but even if they would, enough effort/
cycles have to be put into loading a BPF program into the kernel already.
Reported-by: NJann Horn <jannh@google.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      1aacde3d
  9. 01 7月, 2016 6 次提交
  11. 29 6月, 2016 2 次提交
  13. 28 6月, 2016 3 次提交
  15. 27 6月, 2016 3 次提交
  17. 25 6月, 2016 4 次提交
    • K
      Revert "mm: make faultaround produce old ptes" · 315d09bf
      由 Kirill A. Shutemov 提交于 
      This reverts commit 5c0a85fa.

The commit causes ~6% regression in unixbench.

Let's revert it for now and consider other solution for reclaim problem
later.

Link: http://lkml.kernel.org/r/1465893750-44080-2-git-send-email-kirill.shutemov@linux.intel.comSigned-off-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: N"Huang, Ying" <ying.huang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Vinayak Menon <vinmenon@codeaurora.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      315d09bf
    • A
      mm: mempool: kasan: don't poot mempool objects in quarantine · 9b75a867
      由 Andrey Ryabinin 提交于 
      Currently we may put reserved by mempool elements into quarantine via
kasan_kfree().  This is totally wrong since quarantine may really free
these objects.  So when mempool will try to use such element,
use-after-free will happen.  Or mempool may decide that it no longer
need that element and double-free it.

So don't put object into quarantine in kasan_kfree(), just poison it.
Rename kasan_kfree() to kasan_poison_kfree() to respect that.

Also, we shouldn't use kasan_slab_alloc()/kasan_krealloc() in
kasan_unpoison_element() because those functions may update allocation
stacktrace.  This would be wrong for the most of the remove_element call
sites.

(The only call site where we may want to update alloc stacktrace is
 in mempool_alloc(). Kmemleak solves this by calling
 kmemleak_update_trace(), so we could make something like that too.
 But this is out of scope of this patch).

Fixes: 55834c59 ("mm: kasan: initial memory quarantine implementation")
Link: http://lkml.kernel.org/r/575977C3.1010905@virtuozzo.comSigned-off-by: NAndrey Ryabinin <aryabinin@virtuozzo.com>
Reported-by: NKuthonuzo Luruo <kuthonuzo.luruo@hpe.com>
Acked-by: NAlexander Potapenko <glider@google.com>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: Kostya Serebryany <kcc@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      9b75a867
    • L
      fix up initial thread stack pointer vs thread_info confusion · 7f1a00b6
      由 Linus Torvalds 提交于 
      The INIT_TASK() initializer was similarly confused about the stack vs
thread_info allocation that the allocators had, and that were fixed in
commit b235beea ("Clarify naming of thread info/stack allocators").

The task ->stack pointer only incidentally ends up having the same value
as the thread_info, and in fact that will change.

So fix the initial task struct initializer to point to 'init_stack'
instead of 'init_thread_info', and make sure the ia64 definition for
that exists.

This actually makes the ia64 tsk->stack pointer be sensible for the
initial task, but not for any other task.  As mentioned in commit
b235beea, that whole pointer isn't actually used on ia64, since
task_stack_page() there just points to the (single) allocation.

All the other architectures seem to have copied the 'init_stack'
definition, even if it tended to be generally unusued.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      7f1a00b6
    • L
      Clarify naming of thread info/stack allocators · b235beea
      由 Linus Torvalds 提交于 
      We've had the thread info allocated together with the thread stack for
most architectures for a long time (since the thread_info was split off
from the task struct), but that is about to change.

But the patches that move the thread info to be off-stack (and a part of
the task struct instead) made it clear how confused the allocator and
freeing functions are.

Because the common case was that we share an allocation with the thread
stack and the thread_info, the two pointers were identical.  That
identity then meant that we would have things like

	ti = alloc_thread_info_node(tsk, node);
	...
	tsk->stack = ti;

which certainly _worked_ (since stack and thread_info have the same
value), but is rather confusing: why are we assigning a thread_info to
the stack? And if we move the thread_info away, the "confusing" code
just gets to be entirely bogus.

So remove all this confusion, and make it clear that we are doing the
stack allocation by renaming and clarifying the function names to be
about the stack.  The fact that the thread_info then shares the
allocation is an implementation detail, and not really about the
allocation itself.

This is a pure renaming and type fix: we pass in the same pointer, it's
just that we clarify what the pointer means.

The ia64 code that actually only has one single allocation (for all of
task_struct, thread_info and kernel thread stack) now looks a bit odd,
but since "tsk->stack" is actually not even used there, that oddity
doesn't matter.  It would be a separate thing to clean that up, I
intentionally left the ia64 changes as a pure brute-force renaming and
type change.
Acked-by: NAndy Lutomirski <luto@amacapital.net>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      b235beea
  19. 24 6月, 2016 4 次提交
  21. 23 6月, 2016 2 次提交
  23. 22 6月, 2016 1 次提交
    • D
      rxrpc: Fix exclusive connection handling · cc8feb8e
      由 David Howells 提交于 
      "Exclusive connections" are meant to be used for a single client call and
then scrapped.  The idea is to limit the use of the negotiated security
context.  The current code, however, isn't doing this: it is instead
restricting the socket to a single virtual connection and doing all the
calls over that.

This is changed such that the socket no longer maintains a special virtual
connection over which it will do all the calls, but rather gets a new one
each time a new exclusive call is made.

Further, using a socket option for this is a poor choice.  It should be
done on sendmsg with a control message marker instead so that calls can be
marked exclusive individually.  To that end, add RXRPC_EXCLUSIVE_CALL
which, if passed to sendmsg() as a control message element, will cause the
call to be done on an single-use connection.

The socket option (RXRPC_EXCLUSIVE_CONNECTION) still exists and, if set,
will override any lack of RXRPC_EXCLUSIVE_CALL being specified so that
programs using the setsockopt() will appear to work the same.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
      cc8feb8e
  25. 20 6月, 2016 1 次提交
  27. 19 6月, 2016 2 次提交
    • E
      ipv6: RFC 4884 partial support for SIT/GRE tunnels · 20e1954f
      由 Eric Dumazet 提交于 
      When receiving an ICMPv4 message containing extensions as
defined in RFC 4884, and translating it to ICMPv6 at SIT
or GRE tunnel, we need some extra manipulation in order
to properly forward the extensions.

This patch only takes care of Time Exceeded messages as they
are the ones that typically carry information from various
routers in a fabric during a traceroute session.

It also avoids complex skb logic if the data_len is not
a multiple of 8.

RFC states :

   The "original datagram" field MUST contain at least 128 octets.
   If the original datagram did not contain 128 octets, the
   "original datagram" field MUST be zero padded to 128 octets.

In practice routers use 128 bytes of original datagram, not more.

Initial translation was added in commit ca15a078
("sit: generate icmpv6 error when receiving icmpv4 error")
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Oussama Ghorbel <ghorbel@pivasoftware.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      20e1954f
    • E
      ipv6: translate ICMP_TIME_EXCEEDED to ICMPV6_TIME_EXCEED · 2d7a3b27
      由 Eric Dumazet 提交于 
      For better traceroute/mtr support for SIT and GRE tunnels,
we translate IPV4 ICMP ICMP_TIME_EXCEEDED to ICMPV6_TIME_EXCEED

We also have to translate the IPv4 source IP address of ICMP
message to IPv6 v4mapped.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      2d7a3b27