Commit Graph

26420 Commits

Author SHA1 Message Date
Linus Torvalds
5f520fc318 While doing tests on tracing over the network, I found that the packets
were getting corrupted. In the process I found three bugs. One was the
 culprit, but the other two scared me. After deeper investigation, they
 were not as major as I thought they were, due to a signed compared to
 an unsigned that prevented a negative number from doing actual harm.
 
 The two bigger bugs:
 
  - Mask the ring buffer data page length. There are data flags at the
    high bits of the length field. These were not cleared via the
    length function, and the length could return a negative number.
    (Although the number returned was unsigned, but was assigned to a
    signed number) Luckily, this value was compared to PAGE_SIZE which is
    unsigned and kept it from entering the path that could have caused damage.
 
  - Check the page usage before reusing the ring buffer reader page.
    TCP increments the page ref when passing the page off to the network.
    The page is passed back to the ring buffer for use on free. But
    the page could still be in use by the TCP stack.
 
 Minor bugs:
 
  - Related to the first bug. No need to clear out the unused ring buffer
    data before sending to user space. It is now done by the ring buffer
    code itself.
 
  - Reset pointers after free on error path. There were some cases in
    the error path that pointers were freed but not set to NULL, and could
    have them freed again, having a pointer freed twice.
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Merge tag 'trace-v4.15-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "While doing tests on tracing over the network, I found that the
  packets were getting corrupted.

  In the process I found three bugs.

  One was the culprit, but the other two scared me. After deeper
  investigation, they were not as major as I thought they were, due to a
  signed compared to an unsigned that prevented a negative number from
  doing actual harm.

  The two bigger bugs:

   - Mask the ring buffer data page length. There are data flags at the
     high bits of the length field. These were not cleared via the
     length function, and the length could return a negative number.
     (Although the number returned was unsigned, but was assigned to a
     signed number) Luckily, this value was compared to PAGE_SIZE which
     is unsigned and kept it from entering the path that could have
     caused damage.

   - Check the page usage before reusing the ring buffer reader page.
     TCP increments the page ref when passing the page off to the
     network. The page is passed back to the ring buffer for use on
     free. But the page could still be in use by the TCP stack.

  Minor bugs:

   - Related to the first bug. No need to clear out the unused ring
     buffer data before sending to user space. It is now done by the
     ring buffer code itself.

   - Reset pointers after free on error path. There were some cases in
     the error path that pointers were freed but not set to NULL, and
     could have them freed again, having a pointer freed twice"

* tag 'trace-v4.15-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Fix possible double free on failure of allocating trace buffer
  tracing: Fix crash when it fails to alloc ring buffer
  ring-buffer: Do no reuse reader page if still in use
  tracing: Remove extra zeroing out of the ring buffer page
  ring-buffer: Mask out the info bits when returning buffer page length
2017-12-27 13:06:57 -08:00
Steven Rostedt (VMware)
4397f04575 tracing: Fix possible double free on failure of allocating trace buffer
Jing Xia and Chunyan Zhang reported that on failing to allocate part of the
tracing buffer, memory is freed, but the pointers that point to them are not
initialized back to NULL, and later paths may try to free the freed memory
again. Jing and Chunyan fixed one of the locations that does this, but
missed a spot.

Link: http://lkml.kernel.org/r/20171226071253.8968-1-chunyan.zhang@spreadtrum.com

Cc: stable@vger.kernel.org
Fixes: 737223fbca ("tracing: Consolidate buffer allocation code")
Reported-by: Jing Xia <jing.xia@spreadtrum.com>
Reported-by: Chunyan Zhang <chunyan.zhang@spreadtrum.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-27 14:21:27 -05:00
Jing Xia
24f2aaf952 tracing: Fix crash when it fails to alloc ring buffer
Double free of the ring buffer happens when it fails to alloc new
ring buffer instance for max_buffer if TRACER_MAX_TRACE is configured.
The root cause is that the pointer is not set to NULL after the buffer
is freed in allocate_trace_buffers(), and the freeing of the ring
buffer is invoked again later if the pointer is not equal to Null,
as:

instance_mkdir()
    |-allocate_trace_buffers()
        |-allocate_trace_buffer(tr, &tr->trace_buffer...)
	|-allocate_trace_buffer(tr, &tr->max_buffer...)

          // allocate fail(-ENOMEM),first free
          // and the buffer pointer is not set to null
        |-ring_buffer_free(tr->trace_buffer.buffer)

       // out_free_tr
    |-free_trace_buffers()
        |-free_trace_buffer(&tr->trace_buffer);

	      //if trace_buffer is not null, free again
	    |-ring_buffer_free(buf->buffer)
                |-rb_free_cpu_buffer(buffer->buffers[cpu])
                    // ring_buffer_per_cpu is null, and
                    // crash in ring_buffer_per_cpu->pages

Link: http://lkml.kernel.org/r/20171226071253.8968-1-chunyan.zhang@spreadtrum.com

Cc: stable@vger.kernel.org
Fixes: 737223fbca ("tracing: Consolidate buffer allocation code")
Signed-off-by: Jing Xia <jing.xia@spreadtrum.com>
Signed-off-by: Chunyan Zhang <chunyan.zhang@spreadtrum.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-27 14:21:16 -05:00
Steven Rostedt (VMware)
ae415fa4c5 ring-buffer: Do no reuse reader page if still in use
To free the reader page that is allocated with ring_buffer_alloc_read_page(),
ring_buffer_free_read_page() must be called. For faster performance, this
page can be reused by the ring buffer to avoid having to free and allocate
new pages.

The issue arises when the page is used with a splice pipe into the
networking code. The networking code may up the page counter for the page,
and keep it active while sending it is queued to go to the network. The
incrementing of the page ref does not prevent it from being reused in the
ring buffer, and this can cause the page that is being sent out to the
network to be modified before it is sent by reading new data.

Add a check to the page ref counter, and only reuse the page if it is not
being used anywhere else.

Cc: stable@vger.kernel.org
Fixes: 73a757e631 ("ring-buffer: Return reader page back into existing ring buffer")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-27 14:21:09 -05:00
Steven Rostedt (VMware)
6b7e633fe9 tracing: Remove extra zeroing out of the ring buffer page
The ring_buffer_read_page() takes care of zeroing out any extra data in the
page that it returns. There's no need to zero it out again from the
consumer. It was removed from one consumer of this function, but
read_buffers_splice_read() did not remove it, and worse, it contained a
nasty bug because of it.

Cc: stable@vger.kernel.org
Fixes: 2711ca237a ("ring-buffer: Move zeroing out excess in page to ring buffer code")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-27 14:20:59 -05:00
Steven Rostedt (VMware)
45d8b80c2a ring-buffer: Mask out the info bits when returning buffer page length
Two info bits were added to the "commit" part of the ring buffer data page
when returned to be consumed. This was to inform the user space readers that
events have been missed, and that the count may be stored at the end of the
page.

What wasn't handled, was the splice code that actually called a function to
return the length of the data in order to zero out the rest of the page
before sending it up to user space. These data bits were returned with the
length making the value negative, and that negative value was not checked.
It was compared to PAGE_SIZE, and only used if the size was less than
PAGE_SIZE. Luckily PAGE_SIZE is unsigned long which made the compare an
unsigned compare, meaning the negative size value did not end up causing a
large portion of memory to be randomly zeroed out.

Cc: stable@vger.kernel.org
Fixes: 66a8cb95ed ("ring-buffer: Add place holder recording of dropped events")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-27 14:18:10 -05:00
Linus Torvalds
caf9a82657 Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 PTI preparatory patches from Thomas Gleixner:
 "Todays Advent calendar window contains twentyfour easy to digest
  patches. The original plan was to have twenty three matching the date,
  but a late fixup made that moot.

   - Move the cpu_entry_area mapping out of the fixmap into a separate
     address space. That's necessary because the fixmap becomes too big
     with NRCPUS=8192 and this caused already subtle and hard to
     diagnose failures.

     The top most patch is fresh from today and cures a brain slip of
     that tall grumpy german greybeard, who ignored the intricacies of
     32bit wraparounds.

   - Limit the number of CPUs on 32bit to 64. That's insane big already,
     but at least it's small enough to prevent address space issues with
     the cpu_entry_area map, which have been observed and debugged with
     the fixmap code

   - A few TLB flush fixes in various places plus documentation which of
     the TLB functions should be used for what.

   - Rename the SYSENTER stack to CPU_ENTRY_AREA stack as it is used for
     more than sysenter now and keeping the name makes backtraces
     confusing.

   - Prevent LDT inheritance on exec() by moving it to arch_dup_mmap(),
     which is only invoked on fork().

   - Make vysycall more robust.

   - A few fixes and cleanups of the debug_pagetables code. Check
     PAGE_PRESENT instead of checking the PTE for 0 and a cleanup of the
     C89 initialization of the address hint array which already was out
     of sync with the index enums.

   - Move the ESPFIX init to a different place to prepare for PTI.

   - Several code moves with no functional change to make PTI
     integration simpler and header files less convoluted.

   - Documentation fixes and clarifications"

* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
  x86/cpu_entry_area: Prevent wraparound in setup_cpu_entry_area_ptes() on 32bit
  init: Invoke init_espfix_bsp() from mm_init()
  x86/cpu_entry_area: Move it out of the fixmap
  x86/cpu_entry_area: Move it to a separate unit
  x86/mm: Create asm/invpcid.h
  x86/mm: Put MMU to hardware ASID translation in one place
  x86/mm: Remove hard-coded ASID limit checks
  x86/mm: Move the CR3 construction functions to tlbflush.h
  x86/mm: Add comments to clarify which TLB-flush functions are supposed to flush what
  x86/mm: Remove superfluous barriers
  x86/mm: Use __flush_tlb_one() for kernel memory
  x86/microcode: Dont abuse the TLB-flush interface
  x86/uv: Use the right TLB-flush API
  x86/entry: Rename SYSENTER_stack to CPU_ENTRY_AREA_entry_stack
  x86/doc: Remove obvious weirdnesses from the x86 MM layout documentation
  x86/mm/64: Improve the memory map documentation
  x86/ldt: Prevent LDT inheritance on exec
  x86/ldt: Rework locking
  arch, mm: Allow arch_dup_mmap() to fail
  x86/vsyscall/64: Warn and fail vsyscall emulation in NATIVE mode
  ...
2017-12-23 11:53:04 -08:00
Thomas Gleixner
c10e83f598 arch, mm: Allow arch_dup_mmap() to fail
In order to sanitize the LDT initialization on x86 arch_dup_mmap() must be
allowed to fail. Fix up all instances.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirsky <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: dan.j.williams@intel.com
Cc: hughd@google.com
Cc: keescook@google.com
Cc: kirill.shutemov@linux.intel.com
Cc: linux-mm@kvack.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-22 20:13:01 +01:00
Linus Torvalds
ead68f2161 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller"
 "What's a holiday weekend without some networking bug fixes? [1]

   1) Fix some eBPF JIT bugs wrt. SKB pointers across helper function
      calls, from Daniel Borkmann.

   2) Fix regression from errata limiting change to marvell PHY driver,
      from Zhao Qiang.

   3) Fix u16 overflow in SCTP, from Xin Long.

   4) Fix potential memory leak during bridge newlink, from Nikolay
      Aleksandrov.

   5) Fix BPF selftest build on s390, from Hendrik Brueckner.

   6) Don't append to cfg80211 automatically generated certs file,
      always write new ones from scratch. From Thierry Reding.

   7) Fix sleep in atomic in mac80211 hwsim, from Jia-Ju Bai.

   8) Fix hang on tg3 MTU change with certain chips, from Brian King.

   9) Add stall detection to arc emac driver and reset chip when this
      happens, from Alexander Kochetkov.

  10) Fix MTU limitng in GRE tunnel drivers, from Xin Long.

  11) Fix stmmac timestamping bug due to mis-shifting of field. From
      Fredrik Hallenberg.

  12) Fix metrics match when deleting an ipv4 route. The kernel sets
      some internal metrics bits which the user isn't going to set when
      it makes the delete request. From Phil Sutter.

  13) mvneta driver loop over RX queues limits on "txq_number" :-) Fix
      from Yelena Krivosheev.

  14) Fix double free and memory corruption in get_net_ns_by_id, from
      Eric W. Biederman.

  15) Flush ipv4 FIB tables in the reverse order. Some tables can share
      their actual backing data, in particular this happens for the MAIN
      and LOCAL tables. We have to kill the LOCAL table first, because
      it uses MAIN's backing memory. Fix from Ido Schimmel.

  16) Several eBPF verifier value tracking fixes, from Edward Cree, Jann
      Horn, and Alexei Starovoitov.

  17) Make changes to ipv6 autoflowlabel sysctl really propagate to
      sockets, unless the socket has set the per-socket value
      explicitly. From Shaohua Li.

  18) Fix leaks and double callback invocations of zerocopy SKBs, from
      Willem de Bruijn"

[1] Is this a trick question? "Relaxing"? "Quiet"? "Fine"? - Linus.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (77 commits)
  skbuff: skb_copy_ubufs must release uarg even without user frags
  skbuff: orphan frags before zerocopy clone
  net: reevalulate autoflowlabel setting after sysctl setting
  openvswitch: Fix pop_vlan action for double tagged frames
  ipv6: Honor specified parameters in fibmatch lookup
  bpf: do not allow root to mangle valid pointers
  selftests/bpf: add tests for recent bugfixes
  bpf: fix integer overflows
  bpf: don't prune branches when a scalar is replaced with a pointer
  bpf: force strict alignment checks for stack pointers
  bpf: fix missing error return in check_stack_boundary()
  bpf: fix 32-bit ALU op verification
  bpf: fix incorrect tracking of register size truncation
  bpf: fix incorrect sign extension in check_alu_op()
  bpf/verifier: fix bounds calculation on BPF_RSH
  ipv4: Fix use-after-free when flushing FIB tables
  s390/qeth: fix error handling in checksum cmd callback
  tipc: remove joining group member from congested list
  selftests: net: Adding config fragment CONFIG_NUMA=y
  nfp: bpf: keep track of the offloaded program
  ...
2017-12-21 15:57:30 -08:00
Alexei Starovoitov
82abbf8d2f bpf: do not allow root to mangle valid pointers
Do not allow root to convert valid pointers into unknown scalars.
In particular disallow:
 ptr &= reg
 ptr <<= reg
 ptr += ptr
and explicitly allow:
 ptr -= ptr
since pkt_end - pkt == length

1.
This minimizes amount of address leaks root can do.
In the future may need to further tighten the leaks with kptr_restrict.

2.
If program has such pointer math it's likely a user mistake and
when verifier complains about it right away instead of many instructions
later on invalid memory access it's easier for users to fix their progs.

3.
when register holding a pointer cannot change to scalar it allows JITs to
optimize better. Like 32-bit archs could use single register for pointers
instead of a pair required to hold 64-bit scalars.

4.
reduces architecture dependent behavior. Since code:
r1 = r10;
r1 &= 0xff;
if (r1 ...)
will behave differently arm64 vs x64 and offloaded vs native.

A significant chunk of ptr mangling was allowed by
commit f1174f77b5 ("bpf/verifier: rework value tracking")
yet some of it was allowed even earlier.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-21 02:26:29 +01:00
Alexei Starovoitov
bb7f0f989c bpf: fix integer overflows
There were various issues related to the limited size of integers used in
the verifier:
 - `off + size` overflow in __check_map_access()
 - `off + reg->off` overflow in check_mem_access()
 - `off + reg->var_off.value` overflow or 32-bit truncation of
   `reg->var_off.value` in check_mem_access()
 - 32-bit truncation in check_stack_boundary()

Make sure that any integer math cannot overflow by not allowing
pointer math with large values.

Also reduce the scope of "scalar op scalar" tracking.

Fixes: f1174f77b5 ("bpf/verifier: rework value tracking")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-21 02:15:41 +01:00
Jann Horn
179d1c5602 bpf: don't prune branches when a scalar is replaced with a pointer
This could be made safe by passing through a reference to env and checking
for env->allow_ptr_leaks, but it would only work one way and is probably
not worth the hassle - not doing it will not directly lead to program
rejection.

Fixes: f1174f77b5 ("bpf/verifier: rework value tracking")
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-21 02:15:41 +01:00
Jann Horn
a5ec6ae161 bpf: force strict alignment checks for stack pointers
Force strict alignment checks for stack pointers because the tracking of
stack spills relies on it; unaligned stack accesses can lead to corruption
of spilled registers, which is exploitable.

Fixes: f1174f77b5 ("bpf/verifier: rework value tracking")
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-21 02:15:41 +01:00
Jann Horn
ea25f914dc bpf: fix missing error return in check_stack_boundary()
Prevent indirect stack accesses at non-constant addresses, which would
permit reading and corrupting spilled pointers.

Fixes: f1174f77b5 ("bpf/verifier: rework value tracking")
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-21 02:15:41 +01:00
Jann Horn
468f6eafa6 bpf: fix 32-bit ALU op verification
32-bit ALU ops operate on 32-bit values and have 32-bit outputs.
Adjust the verifier accordingly.

Fixes: f1174f77b5 ("bpf/verifier: rework value tracking")
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-21 02:15:41 +01:00
Jann Horn
0c17d1d2c6 bpf: fix incorrect tracking of register size truncation
Properly handle register truncation to a smaller size.

The old code first mirrors the clearing of the high 32 bits in the bitwise
tristate representation, which is correct. But then, it computes the new
arithmetic bounds as the intersection between the old arithmetic bounds and
the bounds resulting from the bitwise tristate representation. Therefore,
when coerce_reg_to_32() is called on a number with bounds
[0xffff'fff8, 0x1'0000'0007], the verifier computes
[0xffff'fff8, 0xffff'ffff] as bounds of the truncated number.
This is incorrect: The truncated number could also be in the range [0, 7],
and no meaningful arithmetic bounds can be computed in that case apart from
the obvious [0, 0xffff'ffff].

Starting with v4.14, this is exploitable by unprivileged users as long as
the unprivileged_bpf_disabled sysctl isn't set.

Debian assigned CVE-2017-16996 for this issue.

v2:
 - flip the mask during arithmetic bounds calculation (Ben Hutchings)
v3:
 - add CVE number (Ben Hutchings)

Fixes: b03c9f9fdc ("bpf/verifier: track signed and unsigned min/max values")
Signed-off-by: Jann Horn <jannh@google.com>
Acked-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-21 02:15:41 +01:00
Jann Horn
95a762e2c8 bpf: fix incorrect sign extension in check_alu_op()
Distinguish between
BPF_ALU64|BPF_MOV|BPF_K (load 32-bit immediate, sign-extended to 64-bit)
and BPF_ALU|BPF_MOV|BPF_K (load 32-bit immediate, zero-padded to 64-bit);
only perform sign extension in the first case.

Starting with v4.14, this is exploitable by unprivileged users as long as
the unprivileged_bpf_disabled sysctl isn't set.

Debian assigned CVE-2017-16995 for this issue.

v3:
 - add CVE number (Ben Hutchings)

Fixes: 484611357c ("bpf: allow access into map value arrays")
Signed-off-by: Jann Horn <jannh@google.com>
Acked-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-21 02:15:41 +01:00
Edward Cree
4374f256ce bpf/verifier: fix bounds calculation on BPF_RSH
Incorrect signed bounds were being computed.
If the old upper signed bound was positive and the old lower signed bound was
negative, this could cause the new upper signed bound to be too low,
leading to security issues.

Fixes: b03c9f9fdc ("bpf/verifier: track signed and unsigned min/max values")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Edward Cree <ecree@solarflare.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
[jannh@google.com: changed description to reflect bug impact]
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-21 02:15:41 +01:00
David S. Miller
b36025b19a Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:

====================
pull-request: bpf 2017-12-17

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

The main changes are:

1) Fix a corner case in generic XDP where we have non-linear skbs
   but enough tailroom in the skb to not miss to linearizing there,
   from Song.

2) Fix BPF JIT bugs in s390x and ppc64 to not recache skb data when
   BPF context is not skb, from Daniel.

3) Fix a BPF JIT bug in sparc64 where recaching skb data after helper
   call would use the wrong register for the skb, from Daniel.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-18 10:49:22 -05:00
Linus Torvalds
2ffb448ccb Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fix from Thomas Gleixner:
 "A single bugfix which prevents arbitrary sigev_notify values in
  posix-timers"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  posix-timer: Properly check sigevent->sigev_notify
2017-12-17 13:48:50 -08:00
Will Deacon
3382290ed2 locking/barriers: Convert users of lockless_dereference() to READ_ONCE()
[ Note, this is a Git cherry-pick of the following commit:

    506458efaf ("locking/barriers: Convert users of lockless_dereference() to READ_ONCE()")

  ... for easier x86 PTI code testing and back-porting. ]

READ_ONCE() now has an implicit smp_read_barrier_depends() call, so it
can be used instead of lockless_dereference() without any change in
semantics.

Signed-off-by: Will Deacon <will.deacon@arm.com>
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>
Link: http://lkml.kernel.org/r/1508840570-22169-4-git-send-email-will.deacon@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-17 13:57:15 +01:00
Linus Torvalds
7a3c296ae0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Clamp timeouts to INT_MAX in conntrack, from Jay Elliot.

 2) Fix broken UAPI for BPF_PROG_TYPE_PERF_EVENT, from Hendrik
    Brueckner.

 3) Fix locking in ieee80211_sta_tear_down_BA_sessions, from Johannes
    Berg.

 4) Add missing barriers to ptr_ring, from Michael S. Tsirkin.

 5) Don't advertise gigabit in sh_eth when not available, from Thomas
    Petazzoni.

 6) Check network namespace when delivering to netlink taps, from Kevin
    Cernekee.

 7) Kill a race in raw_sendmsg(), from Mohamed Ghannam.

 8) Use correct address in TCP md5 lookups when replying to an incoming
    segment, from Christoph Paasch.

 9) Add schedule points to BPF map alloc/free, from Eric Dumazet.

10) Don't allow silly mtu values to be used in ipv4/ipv6 multicast, also
    from Eric Dumazet.

11) Fix SKB leak in tipc, from Jon Maloy.

12) Disable MAC learning on OVS ports of mlxsw, from Yuval Mintz.

13) SKB leak fix in skB_complete_tx_timestamp(), from Willem de Bruijn.

14) Add some new qmi_wwan device IDs, from Daniele Palmas.

15) Fix static key imbalance in ingress qdisc, from Jiri Pirko.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (76 commits)
  net: qcom/emac: Reduce timeout for mdio read/write
  net: sched: fix static key imbalance in case of ingress/clsact_init error
  net: sched: fix clsact init error path
  ip_gre: fix wrong return value of erspan_rcv
  net: usb: qmi_wwan: add Telit ME910 PID 0x1101 support
  pkt_sched: Remove TC_RED_OFFLOADED from uapi
  net: sched: Move to new offload indication in RED
  net: sched: Add TCA_HW_OFFLOAD
  net: aquantia: Increment driver version
  net: aquantia: Fix typo in ethtool statistics names
  net: aquantia: Update hw counters on hw init
  net: aquantia: Improve link state and statistics check interval callback
  net: aquantia: Fill in multicast counter in ndev stats from hardware
  net: aquantia: Fill ndev stat couters from hardware
  net: aquantia: Extend stat counters to 64bit values
  net: aquantia: Fix hardware DMA stream overload on large MRRS
  net: aquantia: Fix actual speed capabilities reporting
  sock: free skb in skb_complete_tx_timestamp on error
  s390/qeth: update takeover IPs after configuration change
  s390/qeth: lock IP table while applying takeover changes
  ...
2017-12-15 13:08:37 -08:00
Linus Torvalds
1f76a75561 Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking fixes from Ingo Molnar:
 "Misc fixes:

   - Fix a S390 boot hang that was caused by the lock-break logic.
     Remove lock-break to begin with, as review suggested it was
     unreasonably fragile and our confidence in its continued good
     health is lower than our confidence in its removal.

   - Remove the lockdep cross-release checking code for now, because of
     unresolved false positive warnings. This should make lockdep work
     well everywhere again.

   - Get rid of the final (and single) ACCESS_ONCE() straggler and
     remove the API from v4.15.

   - Fix a liblockdep build warning"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  tools/lib/lockdep: Add missing declaration of 'pr_cont()'
  checkpatch: Remove ACCESS_ONCE() warning
  compiler.h: Remove ACCESS_ONCE()
  tools/include: Remove ACCESS_ONCE()
  tools/perf: Convert ACCESS_ONCE() to READ_ONCE()
  locking/lockdep: Remove the cross-release locking checks
  locking/core: Remove break_lock field when CONFIG_GENERIC_LOCKBREAK=y
  locking/core: Fix deadlock during boot on systems with GENERIC_LOCKBREAK
2017-12-15 11:44:59 -08:00
Linus Torvalds
a58653cc1e Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
 "Two fixes: a crash fix for an ARM SoC platform, and kernel-doc
  warnings fixes"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/rt: Do not pull from current CPU if only one CPU to pull
  sched/core: Fix kernel-doc warnings after code movement
2017-12-15 11:40:24 -08:00
Daniel Borkmann
04514d1322 bpf: guarantee r1 to be ctx in case of bpf_helper_changes_pkt_data
Some JITs don't cache skb context on stack in prologue, so when
LD_ABS/IND is used and helper calls yield bpf_helper_changes_pkt_data()
as true, then they temporarily save/restore skb pointer. However,
the assumption that skb always has to be in r1 is a bit of a
gamble. Right now it turned out to be true for all helpers listed
in bpf_helper_changes_pkt_data(), but lets enforce that from verifier
side, so that we make this a guarantee and bail out if the func
proto is misconfigured in future helpers.

In case of BPF helper calls from cBPF, bpf_helper_changes_pkt_data()
is completely unrelevant here (since cBPF is context read-only) and
therefore always false.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2017-12-15 09:19:35 -08:00
Steven Rostedt
f73c52a5bc sched/rt: Do not pull from current CPU if only one CPU to pull
Daniel Wagner reported a crash on the BeagleBone Black SoC.

This is a single CPU architecture, and does not have a functional
arch_send_call_function_single_ipi() implementation which can crash
the kernel if that is called.

As it only has one CPU, it shouldn't be called, but if the kernel is
compiled for SMP, the push/pull RT scheduling logic now calls it for
irq_work if the one CPU is overloaded, it can use that function to call
itself and crash the kernel.

Ideally, we should disable the SCHED_FEAT(RT_PUSH_IPI) if the system
only has a single CPU. But SCHED_FEAT is a constant if sched debugging
is turned off. Another fix can also be used, and this should also help
with normal SMP machines. That is, do not initiate the pull code if
there's only one RT overloaded CPU, and that CPU happens to be the
current CPU that is scheduling in a lower priority task.

Even on a system with many CPUs, if there's many RT tasks waiting to
run on a single CPU, and that CPU schedules in another RT task of lower
priority, it will initiate the PULL logic in case there's a higher
priority RT task on another CPU that is waiting to run. But if there is
no other CPU with waiting RT tasks, it will initiate the RT pull logic
on itself (as it still has RT tasks waiting to run). This is a wasted
effort.

Not only does this help with SMP code where the current CPU is the only
one with RT overloaded tasks, it should also solve the issue that
Daniel encountered, because it will prevent the PULL logic from
executing, as there's only one CPU on the system, and the check added
here will cause it to exit the RT pull code.

Reported-by: Daniel Wagner <wagi@monom.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-rt-users <linux-rt-users@vger.kernel.org>
Cc: stable@vger.kernel.org
Fixes: 4bdced5c9 ("sched/rt: Simplify the IPI based RT balancing logic")
Link: http://lkml.kernel.org/r/20171202130454.4cbbfe8d@vmware.local.home
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-15 16:28:02 +01:00
Thomas Gleixner
cef31d9af9 posix-timer: Properly check sigevent->sigev_notify
timer_create() specifies via sigevent->sigev_notify the signal delivery for
the new timer. The valid modes are SIGEV_NONE, SIGEV_SIGNAL, SIGEV_THREAD
and (SIGEV_SIGNAL | SIGEV_THREAD_ID).

The sanity check in good_sigevent() is only checking the valid combination
for the SIGEV_THREAD_ID bit, i.e. SIGEV_SIGNAL, but if SIGEV_THREAD_ID is
not set it accepts any random value.

This has no real effects on the posix timer and signal delivery code, but
it affects show_timer() which handles the output of /proc/$PID/timers. That
function uses a string array to pretty print sigev_notify. The access to
that array has no bound checks, so random sigev_notify cause access beyond
the array bounds.

Add proper checks for the valid notify modes and remove the SIGEV_THREAD_ID
masking from various code pathes as SIGEV_NONE can never be set in
combination with SIGEV_THREAD_ID.

Reported-by: Eric Biggers <ebiggers3@gmail.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Reported-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Cc: stable@vger.kernel.org
2017-12-15 11:08:40 +01:00
Linus Torvalds
0424378781 Various fix ups.
- Comment fixes
  - Build fix
  - Better memory alloction (don't use NR_CPUS)
  - Configuration fix
  - Build warning fix
  - Enhanced callback parameter (to simplify users of trace hooks)
  - Give up on stack tracing when RCU isn't watching (it's a lost cause)
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Merge tag 'trace-v4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "Various fix-ups:

   - comment fixes

   - build fix

   - better memory alloction (don't use NR_CPUS)

   - configuration fix

   - build warning fix

   - enhanced callback parameter (to simplify users of trace hooks)

   - give up on stack tracing when RCU isn't watching (it's a lost
     cause)"

* tag 'trace-v4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Have stack trace not record if RCU is not watching
  tracing: Pass export pointer as argument to ->write()
  ring-buffer: Remove unused function __rb_data_page_index()
  tracing: make PREEMPTIRQ_EVENTS depend on TRACING
  tracing: Allocate mask_str buffer dynamically
  tracing: always define trace_{irq,preempt}_{enable_disable}
  tracing: Fix code comments in trace.c
2017-12-14 18:21:33 -08:00
Steven Rostedt (VMware)
b00d607bb1 tracing: Have stack trace not record if RCU is not watching
The stack tracer records a stack dump whenever it sees a stack usage that is
more than what it ever saw before. This can happen at any function that is
being traced. If it happens when the CPU is going idle (or other strange
locations), RCU may not be watching, and in this case, the recording of the
stack trace will trigger a warning. There's been lots of efforts to make
hacks to allow stack tracing to proceed even if RCU is not watching, but
this only causes more issues to appear. Simply do not trace a stack if RCU
is not watching. It probably isn't a bad stack anyway.

Acked-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-12-14 20:48:22 -05:00
Sudip Mukherjee
7c2c11b208 arch: define weak abort()
gcc toggle -fisolate-erroneous-paths-dereference (default at -O2
onwards) isolates faulty code paths such as null pointer access, divide
by zero etc.  If gcc port doesnt implement __builtin_trap, an abort() is
generated which causes kernel link error.

In this case, gcc is generating abort due to 'divide by zero' in
lib/mpi/mpih-div.c.

Currently 'frv' and 'arc' are failing.  Previously other arch was also
broken like m32r was fixed by commit d22e3d69ee ("m32r: fix build
failure").

Let's define this weak function which is common for all arch and fix the
problem permanently.  We can even remove the arch specific 'abort' after
this is done.

Link: http://lkml.kernel.org/r/1513118956-8718-1-git-send-email-sudipm.mukherjee@gmail.com
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Cc: Alexey Brodkin <Alexey.Brodkin@synopsys.com>
Cc: Vineet Gupta <Vineet.Gupta1@synopsys.com>
Cc: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-12-14 16:00:49 -08:00
Thiago Rafael Becker
bdcf0a423e kernel: make groups_sort calling a responsibility group_info allocators
In testing, we found that nfsd threads may call set_groups in parallel
for the same entry cached in auth.unix.gid, racing in the call of
groups_sort, corrupting the groups for that entry and leading to
permission denials for the client.

This patch:
 - Make groups_sort globally visible.
 - Move the call to groups_sort to the modifiers of group_info
 - Remove the call to groups_sort from set_groups

Link: http://lkml.kernel.org/r/20171211151420.18655-1-thiago.becker@gmail.com
Signed-off-by: Thiago Rafael Becker <thiago.becker@gmail.com>
Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com>
Reviewed-by: NeilBrown <neilb@suse.com>
Acked-by: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-12-14 16:00:49 -08:00
Dmitry Vyukov
689d77f001 kcov: fix comparison callback signature
Fix a silly copy-paste bug.  We truncated u32 args to u16.

Link: http://lkml.kernel.org/r/20171207101134.107168-1-dvyukov@google.com
Fixes: ded97d2c2b ("kcov: support comparison operands collection")
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Cc: syzkaller@googlegroups.com
Cc: Alexander Potapenko <glider@google.com>
Cc: Vegard Nossum <vegard.nossum@oracle.com>
Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-12-14 16:00:48 -08:00
Eric Dumazet
9147efcbe0 bpf: add schedule points to map alloc/free
While using large percpu maps, htab_map_alloc() can hold
cpu for hundreds of ms.

This patch adds cond_resched() calls to percpu alloc/free
call sites, all running in process context.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2017-12-12 15:27:22 -08:00
Daniel Borkmann
283ca526a9 bpf: fix corruption on concurrent perf_event_output calls
When tracing and networking programs are both attached in the
system and both use event-output helpers that eventually call
into perf_event_output(), then we could end up in a situation
where the tracing attached program runs in user context while
a cls_bpf program is triggered on that same CPU out of softirq
context.

Since both rely on the same per-cpu perf_sample_data, we could
potentially corrupt it. This can only ever happen in a combination
of the two types; all tracing programs use a bpf_prog_active
counter to bail out in case a program is already running on
that CPU out of a different context. XDP and cls_bpf programs
by themselves don't have this issue as they run in the same
context only. Therefore, split both perf_sample_data so they
cannot be accessed from each other.

Fixes: 20b9d7ac48 ("bpf: avoid excessive stack usage for perf_sample_data")
Reported-by: Alexei Starovoitov <ast@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Song Liu <songliubraving@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2017-12-12 09:51:12 -08:00
Ingo Molnar
e966eaeeb6 locking/lockdep: Remove the cross-release locking checks
This code (CONFIG_LOCKDEP_CROSSRELEASE=y and CONFIG_LOCKDEP_COMPLETIONS=y),
while it found a number of old bugs initially, was also causing too many
false positives that caused people to disable lockdep - which is arguably
a worse overall outcome.

If we disable cross-release by default but keep the code upstream then
in practice the most likely outcome is that we'll allow the situation
to degrade gradually, by allowing entropy to introduce more and more
false positives, until it overwhelms maintenance capacity.

Another bad side effect was that people were trying to work around
the false positives by uglifying/complicating unrelated code. There's
a marked difference between annotating locking operations and
uglifying good code just due to bad lock debugging code ...

This gradual decrease in quality happened to a number of debugging
facilities in the kernel, and lockdep is pretty complex already,
so we cannot risk this outcome.

Either cross-release checking can be done right with no false positives,
or it should not be included in the upstream kernel.

( Note that it might make sense to maintain it out of tree and go through
  the false positives every now and then and see whether new bugs were
  introduced. )

Cc: Byungchul Park <byungchul.park@lge.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-12 12:38:51 +01:00
Will Deacon
d89c70356a locking/core: Remove break_lock field when CONFIG_GENERIC_LOCKBREAK=y
When CONFIG_GENERIC_LOCKBEAK=y, locking structures grow an extra int ->break_lock
field which is used to implement raw_spin_is_contended() by setting the field
to 1 when waiting on a lock and clearing it to zero when holding a lock.
However, there are a few problems with this approach:

  - There is a write-write race between a CPU successfully taking the lock
    (and subsequently writing break_lock = 0) and a waiter waiting on
    the lock (and subsequently writing break_lock = 1). This could result
    in a contended lock being reported as uncontended and vice-versa.

  - On machines with store buffers, nothing guarantees that the writes
    to break_lock are visible to other CPUs at any particular time.

  - READ_ONCE/WRITE_ONCE are not used, so the field is potentially
    susceptible to harmful compiler optimisations,

Consequently, the usefulness of this field is unclear and we'd be better off
removing it and allowing architectures to implement raw_spin_is_contended() by
providing a definition of arch_spin_is_contended(), as they can when
CONFIG_GENERIC_LOCKBREAK=n.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Sebastian Ott <sebott@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1511894539-7988-3-git-send-email-will.deacon@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-12 11:24:01 +01:00
Will Deacon
f87f3a328d locking/core: Fix deadlock during boot on systems with GENERIC_LOCKBREAK
Commit:

  a8a217c221 ("locking/core: Remove {read,spin,write}_can_lock()")

removed the definition of raw_spin_can_lock(), causing the GENERIC_LOCKBREAK
spin_lock() routines to poll the ->break_lock field when waiting on a lock.

This has been reported to cause a deadlock during boot on s390, because
the ->break_lock field is also set by the waiters, and can potentially
remain set indefinitely if no other CPUs come in to take the lock after
it has been released.

This patch removes the explicit spinning on ->break_lock from the waiters,
instead relying on the outer trylock() operation to determine when the
lock is available.

Reported-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Tested-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: a8a217c221 ("locking/core: Remove {read,spin,write}_can_lock()")
Link: http://lkml.kernel.org/r/1511894539-7988-2-git-send-email-will.deacon@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-12 11:24:01 +01:00
Linus Torvalds
085bec853a Merge branch 'for-4.15-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup fixes from Tejun Heo:

 - Prateek posted a couple patches to fix a deadlock involving cpuset
   and workqueue. It unfortunately caused a different deadlock and the
   recent workqueue hotplug simplification removed the original
   deadlock, so Prateek's two patches are reverted for now.

 - The new stat code was missing u64_stats initialization. Fixed.

 - Doc and other misc changes

* 'for-4.15-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup: add warning about RT not being supported on cgroup2
  Revert "cgroup/cpuset: remove circular dependency deadlock"
  Revert "cpuset: Make cpuset hotplug synchronous"
  cgroup: properly init u64_stats
  debug cgroup: use task_css_set instead of rcu_dereference
  cpuset: Make cpuset hotplug synchronous
  cgroup/cpuset: remove circular dependency deadlock
2017-12-11 17:10:05 -08:00
Linus Torvalds
72dd379e67 Merge branch 'for-4.15-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
Pull workqueue fixes from Tejun Heo:

 - Lai's hotplug simplifications inadvertently fix a possible deadlock
   involving cpuset and workqueue

 - CPU isolation fix which was reverted due to the changes in the
   housekeeping code resurrected

 - A trivial unused include removal

* 'for-4.15-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: remove unneeded kallsyms include
  workqueue/hotplug: remove the workaround in rebind_workers()
  workqueue/hotplug: simplify workqueue_offline_cpu()
  workqueue: respect isolated cpus when queueing an unbound work
  main: kernel_start: move housekeeping_init() before workqueue_init_early()
2017-12-11 17:07:26 -08:00
Sergey Senozhatsky
01dfee9582 workqueue: remove unneeded kallsyms include
The filw was converted from print_symbol() to %pf some time
ago (044c782ce3 "workqueue: fix checkpatch issues").
kallsyms does not seem to be needed anymore.

Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2017-12-11 07:15:43 -08:00
Randy Dunlap
2064a5ab04 sched/core: Fix kernel-doc warnings after code movement
Fix the following kernel-doc warnings after code restructuring:

  ../kernel/sched/core.c:5113: warning: No description found for parameter 't'
  ../kernel/sched/core.c:5113: warning: Excess function parameter 'interval' description in 'sched_rr_get_interval'

	get rid of set_fs()")

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: abca5fc535 ("sched_rr_get_interval(): move compat to native,
Link: http://lkml.kernel.org/r/995c6ded-b32e-bbe4-d9f5-4d42d121aff1@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-11 16:10:42 +01:00
Jiri Slaby
d70ef22892 futex: futex_wake_op, fix sign_extend32 sign bits
sign_extend32 counts the sign bit parameter from 0, not from 1.  So we
have to use "11" for 12th bit, not "12".

This mistake means we have not allowed negative op and cmp args since
commit 30d6e0a419 ("futex: Remove duplicated code and fix undefined
behaviour") till now.

Fixes: 30d6e0a419 ("futex: Remove duplicated code and fix undefined behaviour")
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Darren Hart <dvhart@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-12-10 12:50:57 -08:00
Linus Torvalds
e9ef1fe312 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) CAN fixes from Martin Kelly (cancel URBs properly in all the CAN usb
    drivers).

 2) Revert returning -EEXIST from __dev_alloc_name() as this propagates
    to userspace and broke some apps. From Johannes Berg.

 3) Fix conn memory leaks and crashes in TIPC, from Jon Malloc and Cong
    Wang.

 4) Gianfar MAC can't do EEE so don't advertise it by default, from
    Claudiu Manoil.

 5) Relax strict netlink attribute validation, but emit a warning. From
    David Ahern.

 6) Fix regression in checksum offload of thunderx driver, from Florian
    Westphal.

 7) Fix UAPI bpf issues on s390, from Hendrik Brueckner.

 8) New card support in iwlwifi, from Ihab Zhaika.

 9) BBR congestion control bug fixes from Neal Cardwell.

10) Fix port stats in nfp driver, from Pieter Jansen van Vuuren.

11) Fix leaks in qualcomm rmnet, from Subash Abhinov Kasiviswanathan.

12) Fix DMA API handling in sh_eth driver, from Thomas Petazzoni.

13) Fix spurious netpoll warnings in bnxt_en, from Calvin Owens.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (67 commits)
  net: mvpp2: fix the RSS table entry offset
  tcp: evaluate packet losses upon RTT change
  tcp: fix off-by-one bug in RACK
  tcp: always evaluate losses in RACK upon undo
  tcp: correctly test congestion state in RACK
  bnxt_en: Fix sources of spurious netpoll warnings
  tcp_bbr: reset long-term bandwidth sampling on loss recovery undo
  tcp_bbr: reset full pipe detection on loss recovery undo
  tcp_bbr: record "full bw reached" decision in new full_bw_reached bit
  sfc: pass valid pointers from efx_enqueue_unwind
  gianfar: Disable EEE autoneg by default
  tcp: invalidate rate samples during SACK reneging
  can: peak/pcie_fd: fix potential bug in restarting tx queue
  can: usb_8dev: cancel urb on -EPIPE and -EPROTO
  can: kvaser_usb: cancel urb on -EPIPE and -EPROTO
  can: esd_usb2: cancel urb on -EPIPE and -EPROTO
  can: ems_usb: cancel urb on -EPIPE and -EPROTO
  can: mcba_usb: cancel urb on -EPROTO
  usbnet: fix alignment for frames with no ethernet header
  tcp: use current time in tcp_rcv_space_adjust()
  ...
2017-12-08 13:32:44 -08:00
Linus Torvalds
968edbd93c KGDB:
* Fix long standing problem with kdb kallsyms_symbol_next() return value
    * Add new co-maintainer Daniel Thompson
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Merge tag 'for_linus-4.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/kgdb

Pull kgdb fixes from Jason Wessel:

 - Fix long standing problem with kdb kallsyms_symbol_next() return
   value

 - Add new co-maintainer Daniel Thompson

* tag 'for_linus-4.15-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/kgdb:
  kgdb/kdb/debug_core: Add co-maintainer Daniel Thompson
  kdb: Fix handling of kallsyms_symbol_next() return value
2017-12-06 18:33:17 -08:00
Linus Torvalds
4b43a3bc20 Merge branch 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull CPU hotplug fix from Ingo Molnar:
 "A single fix moving the smp-call queue flush step to the intended
  point in the state machine"

* 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  smp/hotplug: Move step CPUHP_AP_SMPCFD_DYING to the correct place
2017-12-06 17:45:36 -08:00
Linus Torvalds
e017b4db26 Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
 "This includes a fix for the add_wait_queue() queue ordering brown
  paperbag bug, plus PELT accounting fixes for cgroups scheduling
  artifacts"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/fair: Update and fix the runnable propagation rule
  sched/wait: Fix add_wait_queue() behavioral change
2017-12-06 17:43:26 -08:00
Linus Torvalds
1c7647253c Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "This includes perf namespace support kernel side fixes, plus an
  accumulated set of perf tooling fixes - including UAPI header
  synchronization that should make the perf build less noisy"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (31 commits)
  tooling/headers: Synchronize updated s390 and x86 UAPI headers
  tools headers: Syncronize mman.h ABI header
  tools headers: Synchronize prctl.h ABI header
  tools headers: Synchronize KVM arch ABI headers
  tools headers: Synchronize drm/i915_drm.h
  tools headers uapi: Synchronize drm/drm.h
  tools headers: Synchronize perf_event.h header
  tools headers: Synchronize kernel ABI headers wrt SPDX tags
  tools/headers: Synchronize kernel x86 UAPI headers
  perf intel-pt: Bring instruction decoder files into line with the kernel
  perf test: Fix test 21 for s390x
  perf bench numa: Fixup discontiguous/sparse numa nodes
  perf top: Use signal interface for SIGWINCH handler
  perf top: Fix window dimensions change handling
  perf: Fix header.size for namespace events
  perf top: Ignore kptr_restrict when not sampling the kernel
  perf record: Ignore kptr_restrict when not sampling the kernel
  perf report: Ignore kptr_restrict when not sampling the kernel
  perf evlist: Add helper to check if attr.exclude_kernel is set in all evsels
  perf test shell: Fix test case probe libc's inet_pton on s390x
  ...
2017-12-06 17:41:24 -08:00
Linus Torvalds
189dbab0dd Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull lockdep fix from Ingo Molnar:
 "Fix a possible NULL dereference for the (rare) case when a task
  doesn't have ->xhlocks space allocated due to kmalloc() OOM-ing"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/lockdep: Fix possible NULL deref
2017-12-06 17:39:44 -08:00
Linus Torvalds
61d6be3a7a Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fixes from Ingo Molnar:
 "Two fixes: use bool type consistently, plus a irq_matrix_available()
  bugfix"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqdesc: Use bool return type instead of int
  genirq/matrix: Fix the precedence fix for real
2017-12-06 15:47:51 -08:00
Daniel Thompson
c07d353380 kdb: Fix handling of kallsyms_symbol_next() return value
kallsyms_symbol_next() returns a boolean (true on success). Currently
kdb_read() tests the return value with an inequality that
unconditionally evaluates to true.

This is fixed in the obvious way and, since the conditional branch is
supposed to be unreachable, we also add a WARN_ON().

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
2017-12-06 16:12:43 -06:00