1. 01 4月, 2017 1 次提交
    • M
      mm: move mm_percpu_wq initialization earlier · 597b7305
      Michal Hocko 提交于
      Yang Li has reported that drain_all_pages triggers a WARN_ON which means
      that this function is called earlier than the mm_percpu_wq is
      initialized on arm64 with CMA configured:
      
        WARNING: CPU: 2 PID: 1 at mm/page_alloc.c:2423 drain_all_pages+0x244/0x25c
        Modules linked in:
        CPU: 2 PID: 1 Comm: swapper/0 Not tainted 4.11.0-rc1-next-20170310-00027-g64dfbc5 #127
        Hardware name: Freescale Layerscape 2088A RDB Board (DT)
        task: ffffffc07c4a6d00 task.stack: ffffffc07c4a8000
        PC is at drain_all_pages+0x244/0x25c
        LR is at start_isolate_page_range+0x14c/0x1f0
        [...]
         drain_all_pages+0x244/0x25c
         start_isolate_page_range+0x14c/0x1f0
         alloc_contig_range+0xec/0x354
         cma_alloc+0x100/0x1fc
         dma_alloc_from_contiguous+0x3c/0x44
         atomic_pool_init+0x7c/0x208
         arm64_dma_init+0x44/0x4c
         do_one_initcall+0x38/0x128
         kernel_init_freeable+0x1a0/0x240
         kernel_init+0x10/0xfc
         ret_from_fork+0x10/0x20
      
      Fix this by moving the whole setup_vmstat which is an initcall right now
      to init_mm_internals which will be called right after the WQ subsystem
      is initialized.
      
      Link: http://lkml.kernel.org/r/20170315164021.28532-1-mhocko@kernel.orgSigned-off-by: NMichal Hocko <mhocko@suse.com>
      Reported-by: NYang Li <pku.leo@gmail.com>
      Tested-by: NYang Li <pku.leo@gmail.com>
      Tested-by: NXiaolong Ye <xiaolong.ye@intel.com>
      Cc: Mel Gorman <mgorman@suse.de>
      Cc: Vlastimil Babka <vbabka@suse.cz>
      Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      597b7305
  2. 24 3月, 2017 1 次提交
  3. 22 3月, 2017 5 次提交
  4. 17 3月, 2017 3 次提交
  5. 16 3月, 2017 4 次提交
    • G
      crypto: ccp - Assign DMA commands to the channel's CCP · 7c468447
      Gary R Hook 提交于
      The CCP driver generally uses a round-robin approach when
      assigning operations to available CCPs. For the DMA engine,
      however, the DMA mappings of the SGs are associated with a
      specific CCP. When an IOMMU is enabled, the IOMMU is
      programmed based on this specific device.
      
      If the DMA operations are not performed by that specific
      CCP then addressing errors and I/O page faults will occur.
      
      Update the CCP driver to allow a specific CCP device to be
      requested for an operation and use this in the DMA engine
      support.
      
      Cc: <stable@vger.kernel.org> # 4.9.x-
      Signed-off-by: NGary R Hook <gary.hook@amd.com>
      Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
      7c468447
    • D
      vmbus: remove hv_event_tasklet_disable/enable · dad72a1d
      Dexuan Cui 提交于
      With the recent introduction of per-channel tasklet, we need to update
      the way we handle the 3 concurrency issues:
      
      1. hv_process_channel_removal -> percpu_channel_deq vs.
         vmbus_chan_sched -> list_for_each_entry(..., percpu_list);
      
      2. vmbus_process_offer -> percpu_channel_enq/deq vs. vmbus_chan_sched.
      
      3. vmbus_close_internal vs. the per-channel tasklet vmbus_on_event;
      
      The first 2 issues can be handled by Stephen's recent patch
      "vmbus: use rcu for per-cpu channel list", and the third issue
      can be handled by calling tasklet_disable in vmbus_close_internal here.
      
      We don't need the original hv_event_tasklet_disable/enable since we
      now use per-channel tasklet instead of the previous per-CPU tasklet,
      and actually we must remove them due to the side effect now:
      vmbus_process_offer -> hv_event_tasklet_enable -> tasklet_schedule will
      start the per-channel callback prematurely, cauing NULL dereferencing
      (the channel may haven't been properly configured to run the callback yet).
      
      Fixes: 631e63a9 ("vmbus: change to per channel tasklet")
      Signed-off-by: NDexuan Cui <decui@microsoft.com>
      Cc: "K. Y. Srinivasan" <kys@microsoft.com>
      Cc: Haiyang Zhang <haiyangz@microsoft.com>
      Cc: Stephen Hemminger <sthemmin@microsoft.com>
      Tested-by: NVitaly Kuznetsov <vkuznets@redhat.com>
      Signed-off-by: NK. Y. Srinivasan <kys@microsoft.com>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      dad72a1d
    • S
      vmbus: use rcu for per-cpu channel list · 8200f208
      Stephen Hemminger 提交于
      The per-cpu channel list is now referred to in the interrupt
      routine. This is mostly safe since the host will not normally generate
      an interrupt when channel is being deleted but if it did then there
      would be a use after free problem.
      
      To solve, this use RCU protection on ther per-cpu list.
      
      Fixes: 631e63a9 ("vmbus: change to per channel tasklet")
      Signed-off-by: NStephen Hemminger <sthemmin@microsoft.com>
      Signed-off-by: NK. Y. Srinivasan <kys@microsoft.com>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      8200f208
    • E
      fscrypt: eliminate ->prepare_context() operation · 94840e3c
      Eric Biggers 提交于
      The only use of the ->prepare_context() fscrypt operation was to allow
      ext4 to evict inline data from the inode before ->set_context().
      However, there is no reason why this cannot be done as simply the first
      step in ->set_context(), and in fact it makes more sense to do it that
      way because then the policy modes and flags get validated before any
      real work is done.  Therefore, merge ext4_prepare_context() into
      ext4_set_context(), and remove ->prepare_context().
      Signed-off-by: NEric Biggers <ebiggers@google.com>
      Signed-off-by: NTheodore Ts'o <tytso@mit.edu>
      94840e3c
  6. 14 3月, 2017 3 次提交
  7. 13 3月, 2017 1 次提交
    • D
      bpf: improve read-only handling · 65869a47
      Daniel Borkmann 提交于
      Improve bpf_{prog,jit_binary}_{un,}lock_ro() by throwing a
      one-time warning in case of an error when the image couldn't
      be set read-only, and also mark struct bpf_prog as locked when
      bpf_prog_lock_ro() was called.
      
      Reason for the latter is that bpf_prog_unlock_ro() is called from
      various places including error paths, and we shouldn't mess with
      page attributes when really not needed.
      
      For bpf_jit_binary_unlock_ro() this is not needed as jited flag
      implicitly indicates this, thus for archs with ARCH_HAS_SET_MEMORY
      we're guaranteed to have a previously locked image. Overall, this
      should also help us to identify any further potential issues with
      set_memory_*() helpers.
      Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
      Acked-by: NAlexei Starovoitov <ast@kernel.org>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      65869a47
  8. 11 3月, 2017 3 次提交
  9. 10 3月, 2017 9 次提交
    • D
      net: Work around lockdep limitation in sockets that use sockets · cdfbabfb
      David Howells 提交于
      Lockdep issues a circular dependency warning when AFS issues an operation
      through AF_RXRPC from a context in which the VFS/VM holds the mmap_sem.
      
      The theory lockdep comes up with is as follows:
      
       (1) If the pagefault handler decides it needs to read pages from AFS, it
           calls AFS with mmap_sem held and AFS begins an AF_RXRPC call, but
           creating a call requires the socket lock:
      
      	mmap_sem must be taken before sk_lock-AF_RXRPC
      
       (2) afs_open_socket() opens an AF_RXRPC socket and binds it.  rxrpc_bind()
           binds the underlying UDP socket whilst holding its socket lock.
           inet_bind() takes its own socket lock:
      
      	sk_lock-AF_RXRPC must be taken before sk_lock-AF_INET
      
       (3) Reading from a TCP socket into a userspace buffer might cause a fault
           and thus cause the kernel to take the mmap_sem, but the TCP socket is
           locked whilst doing this:
      
      	sk_lock-AF_INET must be taken before mmap_sem
      
      However, lockdep's theory is wrong in this instance because it deals only
      with lock classes and not individual locks.  The AF_INET lock in (2) isn't
      really equivalent to the AF_INET lock in (3) as the former deals with a
      socket entirely internal to the kernel that never sees userspace.  This is
      a limitation in the design of lockdep.
      
      Fix the general case by:
      
       (1) Double up all the locking keys used in sockets so that one set are
           used if the socket is created by userspace and the other set is used
           if the socket is created by the kernel.
      
       (2) Store the kern parameter passed to sk_alloc() in a variable in the
           sock struct (sk_kern_sock).  This informs sock_lock_init(),
           sock_init_data() and sk_clone_lock() as to the lock keys to be used.
      
           Note that the child created by sk_clone_lock() inherits the parent's
           kern setting.
      
       (3) Add a 'kern' parameter to ->accept() that is analogous to the one
           passed in to ->create() that distinguishes whether kernel_accept() or
           sys_accept4() was the caller and can be passed to sk_alloc().
      
           Note that a lot of accept functions merely dequeue an already
           allocated socket.  I haven't touched these as the new socket already
           exists before we get the parameter.
      
           Note also that there are a couple of places where I've made the accepted
           socket unconditionally kernel-based:
      
      	irda_accept()
      	rds_rcp_accept_one()
      	tcp_accept_from_sock()
      
           because they follow a sock_create_kern() and accept off of that.
      
      Whilst creating this, I noticed that lustre and ocfs don't create sockets
      through sock_create_kern() and thus they aren't marked as for-kernel,
      though they appear to be internal.  I wonder if these should do that so
      that they use the new set of lock keys.
      Signed-off-by: NDavid Howells <dhowells@redhat.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      cdfbabfb
    • A
      userfaultfd: non-cooperative: userfaultfd_remove revalidate vma in MADV_DONTNEED · 70ccb92f
      Andrea Arcangeli 提交于
      userfaultfd_remove() has to be execute before zapping the pagetables or
      UFFDIO_COPY could keep filling pages after zap_page_range returned,
      which would result in non zero data after a MADV_DONTNEED.
      
      However userfaultfd_remove() may have to release the mmap_sem.  This was
      handled correctly in MADV_REMOVE, but MADV_DONTNEED accessed a
      potentially stale vma (the very vma passed to zap_page_range(vma, ...)).
      
      The fix consists in revalidating the vma in case userfaultfd_remove()
      had to release the mmap_sem.
      
      This also optimizes away an unnecessary down_read/up_read in the
      MADV_REMOVE case if UFFD_EVENT_FORK had to be delivered.
      
      It all remains zero runtime cost in case CONFIG_USERFAULTFD=n as
      userfaultfd_remove() will be defined as "true" at build time.
      
      Link: http://lkml.kernel.org/r/20170302173738.18994-3-aarcange@redhat.comSigned-off-by: NAndrea Arcangeli <aarcange@redhat.com>
      Acked-by: NMike Rapoport <rppt@linux.vnet.ibm.com>
      Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
      Cc: Mike Kravetz <mike.kravetz@oracle.com>
      Cc: Pavel Emelyanov <xemul@parallels.com>
      Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      70ccb92f
    • Y
      mm/vmstats: add thp_split_pud event for clarity · ce9311cf
      Yisheng Xie 提交于
      We added support for PUD-sized transparent hugepages, however we count
      the event "thp split pud" into thp_split_pmd event.
      
      To separate the event count of thp split pud from pmd, add a new event
      named thp_split_pud.
      
      Link: http://lkml.kernel.org/r/1488282380-5076-1-git-send-email-xieyisheng1@huawei.comSigned-off-by: NYisheng Xie <xieyisheng1@huawei.com>
      Cc: Vlastimil Babka <vbabka@suse.cz>
      Cc: Johannes Weiner <hannes@cmpxchg.org>
      Cc: Michal Hocko <mhocko@suse.com>
      Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
      Cc: Sebastian Siewior <bigeasy@linutronix.de>
      Cc: Hugh Dickins <hughd@google.com>
      Cc: Christoph Lameter <cl@linux.com>
      Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
      Cc: Mel Gorman <mgorman@techsingularity.net>
      Cc: Andrea Arcangeli <aarcange@redhat.com>
      Cc: Ebru Akagunduz <ebru.akagunduz@gmail.com>
      Cc: David Rientjes <rientjes@google.com>
      Cc: Hanjun Guo <guohanjun@huawei.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      ce9311cf
    • A
      include/linux/fs.h: fix unsigned enum warning with gcc-4.2 · cbfd0c10
      Arnd Bergmann 提交于
      With arm-linux-gcc-4.2, almost every file we build in the kernel ends up
      with this warning:
      
        include/linux/fs.h:2648: warning: comparison of unsigned expression < 0 is always false
      
      Later versions don't have this problem, but it's easy enough to work
      around.
      
      Link: http://lkml.kernel.org/r/20161216105634.235457-12-arnd@arndb.deSigned-off-by: NArnd Bergmann <arnd@arndb.de>
      Cc: Russell King <rmk+kernel@armlinux.org.uk>
      Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      cbfd0c10
    • A
      userfaultfd: non-cooperative: rollback userfaultfd_exit · dd0db88d
      Andrea Arcangeli 提交于
      Patch series "userfaultfd non-cooperative further update for 4.11 merge
      window".
      
      Unfortunately I noticed one relevant bug in userfaultfd_exit while doing
      more testing.  I've been doing testing before and this was also tested
      by kbuild bot and exercised by the selftest, but this bug never
      reproduced before.
      
      I dropped userfaultfd_exit as result.  I dropped it because of
      implementation difficulty in receiving signals in __mmput and because I
      think -ENOSPC as result from the background UFFDIO_COPY should be enough
      already.
      
      Before I decided to remove userfaultfd_exit, I noticed userfaultfd_exit
      wasn't exercised by the selftest and when I tried to exercise it, after
      moving it to a more correct place in __mmput where it would make more
      sense and where the vma list is stable, it resulted in the
      event_wait_completion in D state.  So then I added the second patch to
      be sure even if we call userfaultfd_event_wait_completion too late
      during task exit(), we won't risk to generate tasks in D state.  The
      same check exists in handle_userfault() for the same reason, except it
      makes a difference there, while here is just a robustness check and it's
      run under WARN_ON_ONCE.
      
      While looking at the userfaultfd_event_wait_completion() function I
      looked back at its callers too while at it and I think it's not ok to
      stop executing dup_fctx on the fcs list because we relay on
      userfaultfd_event_wait_completion to execute
      userfaultfd_ctx_put(fctx->orig) which is paired against
      userfaultfd_ctx_get(fctx->orig) in dup_userfault just before
      list_add(fcs).  This change only takes care of fctx->orig but this area
      also needs further review looking for similar problems in fctx->new.
      
      The only patch that is urgent is the first because it's an use after
      free during a SMP race condition that affects all processes if
      CONFIG_USERFAULTFD=y.  Very hard to reproduce though and probably
      impossible without SLUB poisoning enabled.
      
      This patch (of 3):
      
      I once reproduced this oops with the userfaultfd selftest, it's not
      easily reproducible and it requires SLUB poisoning to reproduce.
      
          general protection fault: 0000 [#1] SMP
          Modules linked in:
          CPU: 2 PID: 18421 Comm: userfaultfd Tainted: G               ------------ T 3.10.0+ #15
          Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.10.1-0-g8891697-prebuilt.qemu-project.org 04/01/2014
          task: ffff8801f83b9440 ti: ffff8801f833c000 task.ti: ffff8801f833c000
          RIP: 0010:[<ffffffff81451299>]  [<ffffffff81451299>] userfaultfd_exit+0x29/0xa0
          RSP: 0018:ffff8801f833fe80  EFLAGS: 00010202
          RAX: ffff8801f833ffd8 RBX: 6b6b6b6b6b6b6b6b RCX: ffff8801f83b9440
          RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8800baf18600
          RBP: ffff8801f833fee8 R08: 0000000000000000 R09: 0000000000000001
          R10: 0000000000000000 R11: ffffffff8127ceb3 R12: 0000000000000000
          R13: ffff8800baf186b0 R14: ffff8801f83b99f8 R15: 00007faed746c700
          FS:  0000000000000000(0000) GS:ffff88023fc80000(0000) knlGS:0000000000000000
          CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
          CR2: 00007faf0966f028 CR3: 0000000001bc6000 CR4: 00000000000006e0
          DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
          DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
          Call Trace:
            do_exit+0x297/0xd10
            SyS_exit+0x17/0x20
            tracesys+0xdd/0xe2
          Code: 00 00 66 66 66 66 90 55 48 89 e5 41 54 53 48 83 ec 58 48 8b 1f 48 85 db 75 11 eb 73 66 0f 1f 44 00 00 48 8b 5b 10 48 85 db 74 64 <4c> 8b a3 b8 00 00 00 4d 85 e4 74 eb 41 f6 84 24 2c 01 00 00 80
          RIP  [<ffffffff81451299>] userfaultfd_exit+0x29/0xa0
           RSP <ffff8801f833fe80>
          ---[ end trace 9fecd6dcb442846a ]---
      
      In the debugger I located the "mm" pointer in the stack and walking
      mm->mmap->vm_next through the end shows the vma->vm_next list is fully
      consistent and it is null terminated list as expected.  So this has to
      be an SMP race condition where userfaultfd_exit was running while the
      vma list was being modified by another CPU.
      
      When userfaultfd_exit() run one of the ->vm_next pointers pointed to
      SLAB_POISON (RBX is the vma pointer and is 0x6b6b..).
      
      The reason is that it's not running in __mmput but while there are still
      other threads running and it's not holding the mmap_sem (it can't as it
      has to wait the even to be received by the manager).  So this is an use
      after free that was happening for all processes.
      
      One more implementation problem aside from the race condition:
      userfaultfd_exit has really to check a flag in mm->flags before walking
      the vma or it's going to slowdown the exit() path for regular tasks.
      
      One more implementation problem: at that point signals can't be
      delivered so it would also create a task in D state if the manager
      doesn't read the event.
      
      The major design issue: it overall looks superfluous as the manager can
      check for -ENOSPC in the background transfer:
      
      	if (mmget_not_zero(ctx->mm)) {
      [..]
      	} else {
      		return -ENOSPC;
      	}
      
      It's safer to roll it back and re-introduce it later if at all.
      
      [rppt@linux.vnet.ibm.com: documentation fixup after removal of UFFD_EVENT_EXIT]
        Link: http://lkml.kernel.org/r/1488345437-4364-1-git-send-email-rppt@linux.vnet.ibm.com
      Link: http://lkml.kernel.org/r/20170224181957.19736-2-aarcange@redhat.comSigned-off-by: NAndrea Arcangeli <aarcange@redhat.com>
      Signed-off-by: NMike Rapoport <rppt@linux.vnet.ibm.com>
      Acked-by: NMike Rapoport <rppt@linux.vnet.ibm.com>
      Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
      Cc: Mike Kravetz <mike.kravetz@oracle.com>
      Cc: Pavel Emelyanov <xemul@parallels.com>
      Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      dd0db88d
    • M
      scripts/spelling.txt: add "disble(d)" pattern and fix typo instances · 8a1115ff
      Masahiro Yamada 提交于
      Fix typos and add the following to the scripts/spelling.txt:
      
        disble||disable
        disbled||disabled
      
      I kept the TSL2563_INT_DISBLED in /drivers/iio/light/tsl2563.c
      untouched.  The macro is not referenced at all, but this commit is
      touching only comment blocks just in case.
      
      Link: http://lkml.kernel.org/r/1481573103-11329-20-git-send-email-yamada.masahiro@socionext.comSigned-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
      Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      8a1115ff
    • A
      bpf: convert htab map to hlist_nulls · 4fe84359
      Alexei Starovoitov 提交于
      when all map elements are pre-allocated one cpu can delete and reuse htab_elem
      while another cpu is still walking the hlist. In such case the lookup may
      miss the element. Convert hlist to hlist_nulls to avoid such scenario.
      When bucket lock is taken there is no need to take such precautions,
      so only convert map_lookup and map_get_next to nulls.
      The race window is extremely small and only reproducible with explicit
      udelay() inside lookup_nulls_elem_raw()
      
      Similar to hlist add hlist_nulls_for_each_entry_safe() and
      hlist_nulls_entry_safe() helpers.
      
      Fixes: 6c905981 ("bpf: pre-allocate hash map elements")
      Reported-by: NJonathan Perry <jonperry@fb.com>
      Signed-off-by: NAlexei Starovoitov <ast@kernel.org>
      Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      4fe84359
    • K
      mm: convert generic code to 5-level paging · c2febafc
      Kirill A. Shutemov 提交于
      Convert all non-architecture-specific code to 5-level paging.
      
      It's mostly mechanical adding handling one more page table level in
      places where we deal with pud_t.
      Signed-off-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Acked-by: NMichal Hocko <mhocko@suse.com>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      c2febafc
    • K
      asm-generic: introduce 5level-fixup.h · 505a60e2
      Kirill A. Shutemov 提交于
      We are going to switch core MM to 5-level paging abstraction.
      
      This is preparation step which adds <asm-generic/5level-fixup.h>
      As with 4level-fixup.h, the new header allows quickly make all
      architectures compatible with 5-level paging in core MM.
      
      In long run we would like to switch architectures to properly folded p4d
      level by using <asm-generic/pgtable-nop4d.h>, but it requires more
      changes to arch-specific code.
      Signed-off-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Acked-by: NMichal Hocko <mhocko@suse.com>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      505a60e2
  10. 09 3月, 2017 2 次提交
    • L
      sched/headers: fix up header file dependency on <linux/sched/signal.h> · bd0f9b35
      Linus Torvalds 提交于
      The scheduler header file split and cleanups ended up exposing a few
      nasty header file dependencies, and in particular it showed how we in
      <linux/wait.h> ended up depending on "signal_pending()", which now comes
      from <linux/sched/signal.h>.
      
      That's a very subtle and annoying dependency, which already caused a
      semantic merge conflict (see commit e58bc927 "Pull overlayfs updates
      from Miklos Szeredi", which added that fixup in the merge commit).
      
      It turns out that we can avoid this dependency _and_ improve code
      generation by moving the guts of the fairly nasty helper #define
      __wait_event_interruptible_locked() to out-of-line code.  The code that
      includes the signal_pending() check is all in the slow-path where we
      actually go to sleep waiting for the event anyway, so using a helper
      function is the right thing to do.
      
      Using a helper function is also what we already did for the non-locked
      versions, see the "__wait_event*()" macros and the "prepare_to_wait*()"
      set of helper functions.
      
      We might want to try to unify all these macro games, we have a _lot_ of
      subtly different wait-event loops.  But this is the minimal patch to fix
      the annoying header dependency.
      Acked-by: NIngo Molnar <mingo@kernel.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      bd0f9b35
    • J
      Revert "scsi, block: fix duplicate bdi name registration crashes" · c01228db
      Jan Kara 提交于
      This reverts commit 0dba1314. It causes
      leaking of device numbers for SCSI when SCSI registers multiple gendisks
      for one request_queue in succession. It can be easily reproduced using
      Omar's script [1] on kernel with CONFIG_DEBUG_TEST_DRIVER_REMOVE.
      Furthermore the protection provided by this commit is not needed anymore
      as the problem it was fixing got also fixed by commit 165a5e22
      "block: Move bdi_unregister() to del_gendisk()".
      
      [1]: http://marc.info/?l=linux-block&m=148554717109098&w=2Signed-off-by: NJan Kara <jack@suse.cz>
      Acked-by: NDan Williams <dan.j.williams@intel.com>
      Tested-by: NOmar Sandoval <osandov@fb.com>
      Signed-off-by: NJens Axboe <axboe@fb.com>
      c01228db
  11. 08 3月, 2017 1 次提交
    • E
      dccp: fix use-after-free in dccp_feat_activate_values · 62f8f4d9
      Eric Dumazet 提交于
      Dmitry reported crashes in DCCP stack [1]
      
      Problem here is that when I got rid of listener spinlock, I missed the
      fact that DCCP stores a complex state in struct dccp_request_sock,
      while TCP does not.
      
      Since multiple cpus could access it at the same time, we need to add
      protection.
      
      [1]
      BUG: KASAN: use-after-free in dccp_feat_activate_values+0x967/0xab0
      net/dccp/feat.c:1541 at addr ffff88003713be68
      Read of size 8 by task syz-executor2/8457
      CPU: 2 PID: 8457 Comm: syz-executor2 Not tainted 4.10.0-rc7+ #127
      Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
      Call Trace:
       <IRQ>
       __dump_stack lib/dump_stack.c:15 [inline]
       dump_stack+0x292/0x398 lib/dump_stack.c:51
       kasan_object_err+0x1c/0x70 mm/kasan/report.c:162
       print_address_description mm/kasan/report.c:200 [inline]
       kasan_report_error mm/kasan/report.c:289 [inline]
       kasan_report.part.1+0x20e/0x4e0 mm/kasan/report.c:311
       kasan_report mm/kasan/report.c:332 [inline]
       __asan_report_load8_noabort+0x29/0x30 mm/kasan/report.c:332
       dccp_feat_activate_values+0x967/0xab0 net/dccp/feat.c:1541
       dccp_create_openreq_child+0x464/0x610 net/dccp/minisocks.c:121
       dccp_v6_request_recv_sock+0x1f6/0x1960 net/dccp/ipv6.c:457
       dccp_check_req+0x335/0x5a0 net/dccp/minisocks.c:186
       dccp_v6_rcv+0x69e/0x1d00 net/dccp/ipv6.c:711
       ip6_input_finish+0x46d/0x17a0 net/ipv6/ip6_input.c:279
       NF_HOOK include/linux/netfilter.h:257 [inline]
       ip6_input+0xdb/0x590 net/ipv6/ip6_input.c:322
       dst_input include/net/dst.h:507 [inline]
       ip6_rcv_finish+0x289/0x890 net/ipv6/ip6_input.c:69
       NF_HOOK include/linux/netfilter.h:257 [inline]
       ipv6_rcv+0x12ec/0x23d0 net/ipv6/ip6_input.c:203
       __netif_receive_skb_core+0x1ae5/0x3400 net/core/dev.c:4190
       __netif_receive_skb+0x2a/0x170 net/core/dev.c:4228
       process_backlog+0xe5/0x6c0 net/core/dev.c:4839
       napi_poll net/core/dev.c:5202 [inline]
       net_rx_action+0xe70/0x1900 net/core/dev.c:5267
       __do_softirq+0x2fb/0xb7d kernel/softirq.c:284
       do_softirq_own_stack+0x1c/0x30 arch/x86/entry/entry_64.S:902
       </IRQ>
       do_softirq.part.17+0x1e8/0x230 kernel/softirq.c:328
       do_softirq kernel/softirq.c:176 [inline]
       __local_bh_enable_ip+0x1f2/0x200 kernel/softirq.c:181
       local_bh_enable include/linux/bottom_half.h:31 [inline]
       rcu_read_unlock_bh include/linux/rcupdate.h:971 [inline]
       ip6_finish_output2+0xbb0/0x23d0 net/ipv6/ip6_output.c:123
       ip6_finish_output+0x302/0x960 net/ipv6/ip6_output.c:148
       NF_HOOK_COND include/linux/netfilter.h:246 [inline]
       ip6_output+0x1cb/0x8d0 net/ipv6/ip6_output.c:162
       ip6_xmit+0xcdf/0x20d0 include/net/dst.h:501
       inet6_csk_xmit+0x320/0x5f0 net/ipv6/inet6_connection_sock.c:179
       dccp_transmit_skb+0xb09/0x1120 net/dccp/output.c:141
       dccp_xmit_packet+0x215/0x760 net/dccp/output.c:280
       dccp_write_xmit+0x168/0x1d0 net/dccp/output.c:362
       dccp_sendmsg+0x79c/0xb10 net/dccp/proto.c:796
       inet_sendmsg+0x164/0x5b0 net/ipv4/af_inet.c:744
       sock_sendmsg_nosec net/socket.c:635 [inline]
       sock_sendmsg+0xca/0x110 net/socket.c:645
       SYSC_sendto+0x660/0x810 net/socket.c:1687
       SyS_sendto+0x40/0x50 net/socket.c:1655
       entry_SYSCALL_64_fastpath+0x1f/0xc2
      RIP: 0033:0x4458b9
      RSP: 002b:00007f8ceb77bb58 EFLAGS: 00000282 ORIG_RAX: 000000000000002c
      RAX: ffffffffffffffda RBX: 0000000000000017 RCX: 00000000004458b9
      RDX: 0000000000000023 RSI: 0000000020e60000 RDI: 0000000000000017
      RBP: 00000000006e1b90 R08: 00000000200f9fe1 R09: 0000000000000020
      R10: 0000000000008010 R11: 0000000000000282 R12: 00000000007080a8
      R13: 0000000000000000 R14: 00007f8ceb77c9c0 R15: 00007f8ceb77c700
      Object at ffff88003713be50, in cache kmalloc-64 size: 64
      Allocated:
      PID = 8446
       save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:57
       save_stack+0x43/0xd0 mm/kasan/kasan.c:502
       set_track mm/kasan/kasan.c:514 [inline]
       kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:605
       kmem_cache_alloc_trace+0x82/0x270 mm/slub.c:2738
       kmalloc include/linux/slab.h:490 [inline]
       dccp_feat_entry_new+0x214/0x410 net/dccp/feat.c:467
       dccp_feat_push_change+0x38/0x220 net/dccp/feat.c:487
       __feat_register_sp+0x223/0x2f0 net/dccp/feat.c:741
       dccp_feat_propagate_ccid+0x22b/0x2b0 net/dccp/feat.c:949
       dccp_feat_server_ccid_dependencies+0x1b3/0x250 net/dccp/feat.c:1012
       dccp_make_response+0x1f1/0xc90 net/dccp/output.c:423
       dccp_v6_send_response+0x4ec/0xc20 net/dccp/ipv6.c:217
       dccp_v6_conn_request+0xaba/0x11b0 net/dccp/ipv6.c:377
       dccp_rcv_state_process+0x51e/0x1650 net/dccp/input.c:606
       dccp_v6_do_rcv+0x213/0x350 net/dccp/ipv6.c:632
       sk_backlog_rcv include/net/sock.h:893 [inline]
       __sk_receive_skb+0x36f/0xcc0 net/core/sock.c:479
       dccp_v6_rcv+0xba5/0x1d00 net/dccp/ipv6.c:742
       ip6_input_finish+0x46d/0x17a0 net/ipv6/ip6_input.c:279
       NF_HOOK include/linux/netfilter.h:257 [inline]
       ip6_input+0xdb/0x590 net/ipv6/ip6_input.c:322
       dst_input include/net/dst.h:507 [inline]
       ip6_rcv_finish+0x289/0x890 net/ipv6/ip6_input.c:69
       NF_HOOK include/linux/netfilter.h:257 [inline]
       ipv6_rcv+0x12ec/0x23d0 net/ipv6/ip6_input.c:203
       __netif_receive_skb_core+0x1ae5/0x3400 net/core/dev.c:4190
       __netif_receive_skb+0x2a/0x170 net/core/dev.c:4228
       process_backlog+0xe5/0x6c0 net/core/dev.c:4839
       napi_poll net/core/dev.c:5202 [inline]
       net_rx_action+0xe70/0x1900 net/core/dev.c:5267
       __do_softirq+0x2fb/0xb7d kernel/softirq.c:284
      Freed:
      PID = 15
       save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:57
       save_stack+0x43/0xd0 mm/kasan/kasan.c:502
       set_track mm/kasan/kasan.c:514 [inline]
       kasan_slab_free+0x73/0xc0 mm/kasan/kasan.c:578
       slab_free_hook mm/slub.c:1355 [inline]
       slab_free_freelist_hook mm/slub.c:1377 [inline]
       slab_free mm/slub.c:2954 [inline]
       kfree+0xe8/0x2b0 mm/slub.c:3874
       dccp_feat_entry_destructor.part.4+0x48/0x60 net/dccp/feat.c:418
       dccp_feat_entry_destructor net/dccp/feat.c:416 [inline]
       dccp_feat_list_pop net/dccp/feat.c:541 [inline]
       dccp_feat_activate_values+0x57f/0xab0 net/dccp/feat.c:1543
       dccp_create_openreq_child+0x464/0x610 net/dccp/minisocks.c:121
       dccp_v6_request_recv_sock+0x1f6/0x1960 net/dccp/ipv6.c:457
       dccp_check_req+0x335/0x5a0 net/dccp/minisocks.c:186
       dccp_v6_rcv+0x69e/0x1d00 net/dccp/ipv6.c:711
       ip6_input_finish+0x46d/0x17a0 net/ipv6/ip6_input.c:279
       NF_HOOK include/linux/netfilter.h:257 [inline]
       ip6_input+0xdb/0x590 net/ipv6/ip6_input.c:322
       dst_input include/net/dst.h:507 [inline]
       ip6_rcv_finish+0x289/0x890 net/ipv6/ip6_input.c:69
       NF_HOOK include/linux/netfilter.h:257 [inline]
       ipv6_rcv+0x12ec/0x23d0 net/ipv6/ip6_input.c:203
       __netif_receive_skb_core+0x1ae5/0x3400 net/core/dev.c:4190
       __netif_receive_skb+0x2a/0x170 net/core/dev.c:4228
       process_backlog+0xe5/0x6c0 net/core/dev.c:4839
       napi_poll net/core/dev.c:5202 [inline]
       net_rx_action+0xe70/0x1900 net/core/dev.c:5267
       __do_softirq+0x2fb/0xb7d kernel/softirq.c:284
      Memory state around the buggy address:
       ffff88003713bd00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
       ffff88003713bd80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
      >ffff88003713be00: fc fc fc fc fc fc fc fc fc fc fb fb fb fb fb fb
                                                                ^
      
      Fixes: 079096f1 ("tcp/dccp: install syn_recv requests into ehash table")
      Signed-off-by: NEric Dumazet <edumazet@google.com>
      Reported-by: NDmitry Vyukov <dvyukov@google.com>
      Tested-by: NDmitry Vyukov <dvyukov@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      62f8f4d9
  12. 07 3月, 2017 2 次提交
  13. 06 3月, 2017 3 次提交
  14. 03 3月, 2017 2 次提交