1. 27 Oct, 2015 22 commits
  2. 07 Oct, 2015 18 commits
    • Hin-Tak Leung's avatar
      hfs,hfsplus: cache pages correctly between bnode_create and bnode_free · 2b1aeac0
      Hin-Tak Leung authored
      [ Upstream commit 7cb74be6 ]
      
      Pages looked up by __hfs_bnode_create() (called by hfs_bnode_create() and
      hfs_bnode_find() for finding or creating pages corresponding to an inode)
      are immediately kmap()'ed and used (both read and write) and kunmap()'ed,
      and should not be page_cache_release()'ed until hfs_bnode_free().
      
      This patch fixes a problem I first saw in July 2012: merely running "du"
      on a large hfsplus-mounted directory a few times on a reasonably loaded
      system would get the hfsplus driver all confused and complaining about
      B-tree inconsistencies, and generates a "BUG: Bad page state".  Most
      recently, I can generate this problem on up-to-date Fedora 22 with shipped
      kernel 4.0.5, by running "du /" (="/" + "/home" + "/mnt" + other smaller
      mounts) and "du /mnt" simultaneously on two windows, where /mnt is a
      lightly-used QEMU VM image of the full Mac OS X 10.9:
      
      $ df -i / /home /mnt
      Filesystem                  Inodes   IUsed      IFree IUse% Mounted on
      /dev/mapper/fedora-root    3276800  551665    2725135   17% /
      /dev/mapper/fedora-home   52879360  716221   52163139    2% /home
      /dev/nbd0p2             4294967295 1387818 4293579477    1% /mnt
      
      After applying the patch, I was able to run "du /" (60+ times) and "du
      /mnt" (150+ times) continuously and simultaneously for 6+ hours.
      
      There are many reports of the hfsplus driver getting confused under load
      and generating "BUG: Bad page state" or other similar issues over the
      years.  [1]
      
      The unpatched code [2] has always been wrong since it entered the kernel
      tree.  The only reason why it gets away with it is that the
      kmap/memcpy/kunmap follow very quickly after the page_cache_release() so
      the kernel has not had a chance to reuse the memory for something else,
      most of the time.
      
      The current RW driver appears to have followed the design and development
      of the earlier read-only hfsplus driver [3], where-by version 0.1 (Dec
      2001) had a B-tree node-centric approach to
      read_cache_page()/page_cache_release() per bnode_get()/bnode_put(),
      migrating towards version 0.2 (June 2002) of caching and releasing pages
      per inode extents.  When the current RW code first entered the kernel [2]
      in 2005, there was an REF_PAGES conditional (and "//" commented out code)
      to switch between B-node centric paging to inode-centric paging.  There
      was a mistake with the direction of one of the REF_PAGES conditionals in
      __hfs_bnode_create().  In a subsequent "remove debug code" commit [4], the
      read_cache_page()/page_cache_release() per bnode_get()/bnode_put() were
      removed, but a page_cache_release() was mistakenly left in (propagating
      the "REF_PAGES <-> !REF_PAGE" mistake), and the commented-out
      page_cache_release() in bnode_release() (which should be spanned by
      !REF_PAGES) was never enabled.
      
      References:
      [1]:
      Michael Fox, Apr 2013
      http://www.spinics.net/lists/linux-fsdevel/msg63807.html
      ("hfsplus volume suddenly inaccessable after 'hfs: recoff %d too large'")
      
      Sasha Levin, Feb 2015
      http://lkml.org/lkml/2015/2/20/85 ("use after free")
      
      https://bugs.launchpad.net/ubuntu/+source/linux/+bug/740814
      https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1027887
      https://bugzilla.kernel.org/show_bug.cgi?id=42342
      https://bugzilla.kernel.org/show_bug.cgi?id=63841
      https://bugzilla.kernel.org/show_bug.cgi?id=78761
      
      [2]:
      http://git.kernel.org/cgit/linux/kernel/git/tglx/history.git/commit/\
      fs/hfs/bnode.c?id=d1081202
      commit d1081202
      Author: Andrew Morton <akpm@osdl.org>
      Date:   Wed Feb 25 16:17:36 2004 -0800
      
          [PATCH] HFS rewrite
      
      http://git.kernel.org/cgit/linux/kernel/git/tglx/history.git/commit/\
      fs/hfsplus/bnode.c?id=91556682
      
      commit 91556682
      Author: Andrew Morton <akpm@osdl.org>
      Date:   Wed Feb 25 16:17:48 2004 -0800
      
          [PATCH] HFS+ support
      
      [3]:
      http://sourceforge.net/projects/linux-hfsplus/
      
      http://sourceforge.net/projects/linux-hfsplus/files/Linux%202.4.x%20patch/hfsplus%200.1/
      http://sourceforge.net/projects/linux-hfsplus/files/Linux%202.4.x%20patch/hfsplus%200.2/
      
      http://linux-hfsplus.cvs.sourceforge.net/viewvc/linux-hfsplus/linux/\
      fs/hfsplus/bnode.c?r1=1.4&r2=1.5
      
      Date:   Thu Jun 6 09:45:14 2002 +0000
      Use buffer cache instead of page cache in bnode.c. Cache inode extents.
      
      [4]:
      http://git.kernel.org/cgit/linux/kernel/git/\
      stable/linux-stable.git/commit/?id=a5e3985f
      
      commit a5e3985f
      Author: Roman Zippel <zippel@linux-m68k.org>
      Date:   Tue Sep 6 15:18:47 2005 -0700
      
      [PATCH] hfs: remove debug code
      Signed-off-by: default avatarHin-Tak Leung <htl10@users.sourceforge.net>
      Signed-off-by: default avatarSergei Antonov <saproj@gmail.com>
      Reviewed-by: default avatarAnton Altaparmakov <anton@tuxera.com>
      Reported-by: default avatarSasha Levin <sasha.levin@oracle.com>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      Cc: Christoph Hellwig <hch@infradead.org>
      Cc: Vyacheslav Dubeyko <slava@dubeyko.com>
      Cc: Sougata Santra <sougata@tuxera.com>
      Cc: <stable@vger.kernel.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarSasha Levin <sasha.levin@oracle.com>
      2b1aeac0
    • Noa Osherovich's avatar
      IB/mlx4: Use correct SL on AH query under RoCE · a84c2563
      Noa Osherovich authored
      [ Upstream commit 5e99b139 ]
      
      The mlx4 IB driver implementation for ib_query_ah used a wrong offset
      (28 instead of 29) when link type is Ethernet. Fixed to use the correct one.
      
      Fixes: fa417f7b ('IB/mlx4: Add support for IBoE')
      Signed-off-by: default avatarShani Michaeli <shanim@mellanox.com>
      Signed-off-by: default avatarNoa Osherovich <noaos@mellanox.com>
      Signed-off-by: default avatarOr Gerlitz <ogerlitz@mellanox.com>
      Signed-off-by: default avatarDoug Ledford <dledford@redhat.com>
      Signed-off-by: default avatarSasha Levin <sasha.levin@oracle.com>
      a84c2563
    • Jack Morgenstein's avatar
      IB/mlx4: Forbid using sysfs to change RoCE pkeys · 64665b05
      Jack Morgenstein authored
      [ Upstream commit 2b135db3 ]
      
      The pkey mapping for RoCE must remain the default mapping:
      VFs:
        virtual index 0 = mapped to real index 0 (0xFFFF)
        All others indices: mapped to a real pkey index containing an
                            invalid pkey.
      PF:
        virtual index i = real index i.
      
      Don't allow users to change these mappings using files found in
      sysfs.
      
      Fixes: c1e7e466 ('IB/mlx4: Add iov directory in sysfs under the ib device')
      Signed-off-by: default avatarJack Morgenstein <jackm@dev.mellanox.co.il>
      Signed-off-by: default avatarOr Gerlitz <ogerlitz@mellanox.com>
      Signed-off-by: default avatarDoug Ledford <dledford@redhat.com>
      Signed-off-by: default avatarSasha Levin <sasha.levin@oracle.com>
      64665b05
    • Yishai Hadas's avatar
      IB/uverbs: Fix race between ib_uverbs_open and remove_one · edf5a729
      Yishai Hadas authored
      [ Upstream commit 35d4a0b6 ]
      
      Fixes: 2a72f212 ("IB/uverbs: Remove dev_table")
      
      Before this commit there was a device look-up table that was protected
      by a spin_lock used by ib_uverbs_open and by ib_uverbs_remove_one. When
      it was dropped and container_of was used instead, it enabled the race
      with remove_one as dev might be freed just after:
      dev = container_of(inode->i_cdev, struct ib_uverbs_device, cdev) but
      before the kref_get.
      
      In addition, this buggy patch added some dead code as
      container_of(x,y,z) can never be NULL and so dev can never be NULL.
      As a result the comment above ib_uverbs_open saying "the open method
      will either immediately run -ENXIO" is wrong as it can never happen.
      
      The solution follows Jason Gunthorpe suggestion from below URL:
      https://www.mail-archive.com/linux-rdma@vger.kernel.org/msg25692.html
      
      cdev will hold a kref on the parent (the containing structure,
      ib_uverbs_device) and only when that kref is released it is
      guaranteed that open will never be called again.
      
      In addition, fixes the active count scheme to use an atomic
      not a kref to prevent WARN_ON as pointed by above comment
      from Jason.
      Signed-off-by: default avatarYishai Hadas <yishaih@mellanox.com>
      Signed-off-by: default avatarShachar Raindel <raindel@mellanox.com>
      Reviewed-by: default avatarJason Gunthorpe <jgunthorpe@obsidianresearch.com>
      Signed-off-by: default avatarDoug Ledford <dledford@redhat.com>
      Signed-off-by: default avatarSasha Levin <sasha.levin@oracle.com>
      edf5a729
    • Christoph Hellwig's avatar
      IB/uverbs: reject invalid or unknown opcodes · 8e75f06a
      Christoph Hellwig authored
      [ Upstream commit b632ffa7 ]
      
      We have many WR opcodes that are only supported in kernel space
      and/or require optional information to be copied into the WR
      structure.  Reject all those not explicitly handled so that we
      can't pass invalid information to drivers.
      
      Cc: stable@vger.kernel.org
      Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
      Reviewed-by: default avatarJason Gunthorpe <jgunthorpe@obsidianresearch.com>
      Reviewed-by: default avatarSagi Grimberg <sagig@mellanox.com>
      Signed-off-by: default avatarDoug Ledford <dledford@redhat.com>
      Signed-off-by: default avatarSasha Levin <sasha.levin@oracle.com>
      8e75f06a
    • Mike Marciniszyn's avatar
      IB/qib: Change lkey table allocation to support more MRs · b027811d
      Mike Marciniszyn authored
      [ Upstream commit d6f1c17e ]
      
      The lkey table is allocated with with a get_user_pages() with an
      order based on a number of index bits from a module parameter.
      
      The underlying kernel code cannot allocate that many contiguous pages.
      
      There is no reason the underlying memory needs to be physically
      contiguous.
      
      This patch:
      - switches the allocation/deallocation to vmalloc/vfree
      - caps the number of bits to 23 to insure at least 1 generation bit
        o this matches the module parameter description
      
      Cc: stable@vger.kernel.org
      Reviewed-by: default avatarVinit Agnihotri <vinit.abhay.agnihotri@intel.com>
      Signed-off-by: default avatarMike Marciniszyn <mike.marciniszyn@intel.com>
      Signed-off-by: default avatarDoug Ledford <dledford@redhat.com>
      Signed-off-by: default avatarSasha Levin <sasha.levin@oracle.com>
      b027811d
    • Hin-Tak Leung's avatar
      hfs: fix B-tree corruption after insertion at position 0 · 3d7f1ecf
      Hin-Tak Leung authored
      [ Upstream commit b4cc0efe ]
      
      Fix B-tree corruption when a new record is inserted at position 0 in the
      node in hfs_brec_insert().
      
      This is an identical change to the corresponding hfs b-tree code to Sergei
      Antonov's "hfsplus: fix B-tree corruption after insertion at position 0",
      to keep similar code paths in the hfs and hfsplus drivers in sync, where
      appropriate.
      Signed-off-by: default avatarHin-Tak Leung <htl10@users.sourceforge.net>
      Cc: Sergei Antonov <saproj@gmail.com>
      Cc: Joe Perches <joe@perches.com>
      Reviewed-by: default avatarVyacheslav Dubeyko <slava@dubeyko.com>
      Cc: Anton Altaparmakov <anton@tuxera.com>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      Cc: Christoph Hellwig <hch@infradead.org>
      Cc: <stable@vger.kernel.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarSasha Levin <sasha.levin@oracle.com>
      3d7f1ecf
    • NeilBrown's avatar
      md/raid10: always set reshape_safe when initializing reshape_position. · 9736e5f1
      NeilBrown authored
      [ Upstream commit 299b0685 ]
      
      'reshape_position' tracks where in the reshape we have reached.
      'reshape_safe' tracks where in the reshape we have safely recorded
      in the metadata.
      
      These are compared to determine when to update the metadata.
      So it is important that reshape_safe is initialised properly.
      Currently it isn't.  When starting a reshape from the beginning
      it usually has the correct value by luck.  But when reducing the
      number of devices in a RAID10, it has the wrong value and this leads
      to the metadata not being updated correctly.
      This can lead to corruption if the reshape is not allowed to complete.
      
      This patch is suitable for any -stable kernel which supports RAID10
      reshape, which is 3.5 and later.
      
      Fixes: 3ea7daa5 ("md/raid10: add reshape support")
      Cc: stable@vger.kernel.org (v3.5+ please wait for -final to be out for 2 weeks)
      Signed-off-by: default avatarNeilBrown <neilb@suse.com>
      Signed-off-by: default avatarSasha Levin <sasha.levin@oracle.com>
      9736e5f1
    • Jialing Fu's avatar
      mmc: core: fix race condition in mmc_wait_data_done · 21901ab7
      Jialing Fu authored
      [ Upstream commit 71f8a4b8 ]
      
      The following panic is captured in ker3.14, but the issue still exists
      in latest kernel.
      ---------------------------------------------------------------------
      [   20.738217] c0 3136 (Compiler) Unable to handle kernel NULL pointer dereference
      at virtual address 00000578
      ......
      [   20.738499] c0 3136 (Compiler) PC is at _raw_spin_lock_irqsave+0x24/0x60
      [   20.738527] c0 3136 (Compiler) LR is at _raw_spin_lock_irqsave+0x20/0x60
      [   20.740134] c0 3136 (Compiler) Call trace:
      [   20.740165] c0 3136 (Compiler) [<ffffffc0008ee900>] _raw_spin_lock_irqsave+0x24/0x60
      [   20.740200] c0 3136 (Compiler) [<ffffffc0000dd024>] __wake_up+0x1c/0x54
      [   20.740230] c0 3136 (Compiler) [<ffffffc000639414>] mmc_wait_data_done+0x28/0x34
      [   20.740262] c0 3136 (Compiler) [<ffffffc0006391a0>] mmc_request_done+0xa4/0x220
      [   20.740314] c0 3136 (Compiler) [<ffffffc000656894>] sdhci_tasklet_finish+0xac/0x264
      [   20.740352] c0 3136 (Compiler) [<ffffffc0000a2b58>] tasklet_action+0xa0/0x158
      [   20.740382] c0 3136 (Compiler) [<ffffffc0000a2078>] __do_softirq+0x10c/0x2e4
      [   20.740411] c0 3136 (Compiler) [<ffffffc0000a24bc>] irq_exit+0x8c/0xc0
      [   20.740439] c0 3136 (Compiler) [<ffffffc00008489c>] handle_IRQ+0x48/0xac
      [   20.740469] c0 3136 (Compiler) [<ffffffc000081428>] gic_handle_irq+0x38/0x7c
      ----------------------------------------------------------------------
      Because in SMP, "mrq" has race condition between below two paths:
      path1: CPU0: <tasklet context>
        static void mmc_wait_data_done(struct mmc_request *mrq)
        {
           mrq->host->context_info.is_done_rcv = true;
           //
           // If CPU0 has just finished "is_done_rcv = true" in path1, and at
           // this moment, IRQ or ICache line missing happens in CPU0.
           // What happens in CPU1 (path2)?
           //
           // If the mmcqd thread in CPU1(path2) hasn't entered to sleep mode:
           // path2 would have chance to break from wait_event_interruptible
           // in mmc_wait_for_data_req_done and continue to run for next
           // mmc_request (mmc_blk_rw_rq_prep).
           //
           // Within mmc_blk_rq_prep, mrq is cleared to 0.
           // If below line still gets host from "mrq" as the result of
           // compiler, the panic happens as we traced.
           wake_up_interruptible(&mrq->host->context_info.wait);
        }
      
      path2: CPU1: <The mmcqd thread runs mmc_queue_thread>
        static int mmc_wait_for_data_req_done(...
        {
           ...
           while (1) {
                 wait_event_interruptible(context_info->wait,
                         (context_info->is_done_rcv ||
                          context_info->is_new_req));
           	   static void mmc_blk_rw_rq_prep(...
                 {
                 ...
                 memset(brq, 0, sizeof(struct mmc_blk_request));
      
      This issue happens very coincidentally; however adding mdelay(1) in
      mmc_wait_data_done as below could duplicate it easily.
      
         static void mmc_wait_data_done(struct mmc_request *mrq)
         {
           mrq->host->context_info.is_done_rcv = true;
      +    mdelay(1);
           wake_up_interruptible(&mrq->host->context_info.wait);
          }
      
      At runtime, IRQ or ICache line missing may just happen at the same place
      of the mdelay(1).
      
      This patch gets the mmc_context_info at the beginning of function, it can
      avoid this race condition.
      Signed-off-by: default avatarJialing Fu <jlfu@marvell.com>
      Tested-by: default avatarShawn Lin <shawn.lin@rock-chips.com>
      Fixes: 2220eedf ("mmc: fix async request mechanism ....")
      Signed-off-by: default avatarShawn Lin <shawn.lin@rock-chips.com>
      Signed-off-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
      Signed-off-by: default avatarSasha Levin <sasha.levin@oracle.com>
      21901ab7
    • Jann Horn's avatar
      fs: if a coredump already exists, unlink and recreate with O_EXCL · 5068ce15
      Jann Horn authored
      [ Upstream commit fbb18169 ]
      
      It was possible for an attacking user to trick root (or another user) into
      writing his coredumps into an attacker-readable, pre-existing file using
      rename() or link(), causing the disclosure of secret data from the victim
      process' virtual memory.  Depending on the configuration, it was also
      possible to trick root into overwriting system files with coredumps.  Fix
      that issue by never writing coredumps into existing files.
      
      Requirements for the attack:
       - The attack only applies if the victim's process has a nonzero
         RLIMIT_CORE and is dumpable.
       - The attacker can trick the victim into coredumping into an
         attacker-writable directory D, either because the core_pattern is
         relative and the victim's cwd is attacker-writable or because an
         absolute core_pattern pointing to a world-writable directory is used.
       - The attacker has one of these:
        A: on a system with protected_hardlinks=0:
           execute access to a folder containing a victim-owned,
           attacker-readable file on the same partition as D, and the
           victim-owned file will be deleted before the main part of the attack
           takes place. (In practice, there are lots of files that fulfill
           this condition, e.g. entries in Debian's /var/lib/dpkg/info/.)
           This does not apply to most Linux systems because most distros set
           protected_hardlinks=1.
        B: on a system with protected_hardlinks=1:
           execute access to a folder containing a victim-owned,
           attacker-readable and attacker-writable file on the same partition
           as D, and the victim-owned file will be deleted before the main part
           of the attack takes place.
           (This seems to be uncommon.)
        C: on any system, independent of protected_hardlinks:
           write access to a non-sticky folder containing a victim-owned,
           attacker-readable file on the same partition as D
           (This seems to be uncommon.)
      
      The basic idea is that the attacker moves the victim-owned file to where
      he expects the victim process to dump its core.  The victim process dumps
      its core into the existing file, and the attacker reads the coredump from
      it.
      
      If the attacker can't move the file because he does not have write access
      to the containing directory, he can instead link the file to a directory
      he controls, then wait for the original link to the file to be deleted
      (because the kernel checks that the link count of the corefile is 1).
      
      A less reliable variant that requires D to be non-sticky works with link()
      and does not require deletion of the original link: link() the file into
      D, but then unlink() it directly before the kernel performs the link count
      check.
      
      On systems with protected_hardlinks=0, this variant allows an attacker to
      not only gain information from coredumps, but also clobber existing,
      victim-writable files with coredumps.  (This could theoretically lead to a
      privilege escalation.)
      Signed-off-by: default avatarJann Horn <jann@thejh.net>
      Cc: Kees Cook <keescook@chromium.org>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarSasha Levin <sasha.levin@oracle.com>
      5068ce15
    • Jaewon Kim's avatar
      vmscan: fix increasing nr_isolated incurred by putback unevictable pages · e6064491
      Jaewon Kim authored
      [ Upstream commit c54839a7 ]
      
      reclaim_clean_pages_from_list() assumes that shrink_page_list() returns
      number of pages removed from the candidate list.  But shrink_page_list()
      puts back mlocked pages without passing it to caller and without
      counting as nr_reclaimed.  This increases nr_isolated.
      
      To fix this, this patch changes shrink_page_list() to pass unevictable
      pages back to caller.  Caller will take care those pages.
      
      Minchan said:
      
      It fixes two issues.
      
      1. With unevictable page, cma_alloc will be successful.
      
      Exactly speaking, cma_alloc of current kernel will fail due to
      unevictable pages.
      
      2. fix leaking of NR_ISOLATED counter of vmstat
      
      With it, too_many_isolated works.  Otherwise, it could make hang until
      the process get SIGKILL.
      Signed-off-by: default avatarJaewon Kim <jaewon31.kim@samsung.com>
      Acked-by: default avatarMinchan Kim <minchan@kernel.org>
      Cc: Mel Gorman <mgorman@techsingularity.net>
      Acked-by: default avatarVlastimil Babka <vbabka@suse.cz>
      Cc: <stable@vger.kernel.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarSasha Levin <sasha.levin@oracle.com>
      e6064491
    • Helge Deller's avatar
      parisc: Filter out spurious interrupts in PA-RISC irq handler · c9cfe460
      Helge Deller authored
      [ Upstream commit b1b4e435 ]
      
      When detecting a serial port on newer PA-RISC machines (with iosapic) we have a
      long way to go to find the right IRQ line, registering it, then registering the
      serial port and the irq handler for the serial port. During this phase spurious
      interrupts for the serial port may happen which then crashes the kernel because
      the action handler might not have been set up yet.
      
      So, basically it's a race condition between the serial port hardware and the
      CPU which sets up the necessary fields in the irq sructs. The main reason for
      this race is, that we unmask the serial port irqs too early without having set
      up everything properly before (which isn't easily possible because we need the
      IRQ number to register the serial ports).
      
      This patch is a work-around for this problem. It adds checks to the CPU irq
      handler to verify if the IRQ action field has been initialized already. If not,
      we just skip this interrupt (which isn't critical for a serial port at bootup).
      The real fix would probably involve rewriting all PA-RISC specific IRQ code
      (for CPU, IOSAPIC, GSC and EISA) to use IRQ domains with proper parenting of
      the irq chips and proper irq enabling along this line.
      
      This bug has been in the PA-RISC port since the beginning, but the crashes
      happened very rarely with currently used hardware.  But on the latest machine
      which I bought (a C8000 workstation), which uses the fastest CPUs (4 x PA8900,
      1GHz) and which has the largest possible L1 cache size (64MB each), the kernel
      crashed at every boot because of this race. So, without this patch the machine
      would currently be unuseable.
      
      For the record, here is the flow logic:
      1. serial_init_chip() in 8250_gsc.c calls iosapic_serial_irq().
      2. iosapic_serial_irq() calls txn_alloc_irq() to find the irq.
      3. iosapic_serial_irq() calls cpu_claim_irq() to register the CPU irq
      4. cpu_claim_irq() unmasks the CPU irq (which it shouldn't!)
      5. serial_init_chip() then registers the 8250 port.
      Problems:
      - In step 4 the CPU irq shouldn't have been registered yet, but after step 5
      - If serial irq happens between 4 and 5 have finished, the kernel will crash
      Signed-off-by: default avatarHelge Deller <deller@gmx.de>
      Signed-off-by: default avatarSasha Levin <sasha.levin@oracle.com>
      c9cfe460
    • John David Anglin's avatar
      parisc: Use double word condition in 64bit CAS operation · 4ea349a7
      John David Anglin authored
      [ Upstream commit 1b59ddfc ]
      
      The attached change fixes the condition used in the "sub" instruction.
      A double word comparison is needed.  This fixes the 64-bit LWS CAS
      operation on 64-bit kernels.
      
      I can now enable 64-bit atomic support in GCC.
      
      Cc: <stable@vger.kernel.org>
      Signed-off-by: John David Anglin <dave.anglin>
      Signed-off-by: default avatarHelge Deller <deller@gmx.de>
      Signed-off-by: default avatarSasha Levin <sasha.levin@oracle.com>
      4ea349a7
    • Trond Myklebust's avatar
      NFS: nfs_set_pgio_error sometimes misses errors · 8c87cb09
      Trond Myklebust authored
      [ Upstream commit e9ae58ae ]
      
      We should ensure that we always set the pgio_header's error field
      if a READ or WRITE RPC call returns an error. The current code depends
      on 'hdr->good_bytes' always being initialised to a large value, which
      is not always done correctly by callers.
      When this happens, applications may end up missing important errors.
      
      Cc: stable@vger.kernel.org
      Signed-off-by: default avatarTrond Myklebust <trond.myklebust@primarydata.com>
      Signed-off-by: default avatarSasha Levin <sasha.levin@oracle.com>
      8c87cb09
    • Kinglong Mee's avatar
      NFS: Fix a NULL pointer dereference of migration recovery ops for v4.2 client · 7730c1b9
      Kinglong Mee authored
      [ Upstream commit 18e3b739 ]
      
      ---Steps to Reproduce--
      <nfs-server>
      # cat /etc/exports
      /nfs/referal  *(rw,insecure,no_subtree_check,no_root_squash,crossmnt)
      /nfs/old      *(ro,insecure,subtree_check,root_squash,crossmnt)
      
      <nfs-client>
      # mount -t nfs nfs-server:/nfs/ /mnt/
      # ll /mnt/*/
      
      <nfs-server>
      # cat /etc/exports
      /nfs/referal   *(rw,insecure,no_subtree_check,no_root_squash,crossmnt,refer=/nfs/old/@nfs-server)
      /nfs/old       *(ro,insecure,subtree_check,root_squash,crossmnt)
      # service nfs restart
      
      <nfs-client>
      # ll /mnt/*/    --->>>>> oops here
      
      [ 5123.102925] BUG: unable to handle kernel NULL pointer dereference at           (null)
      [ 5123.103363] IP: [<ffffffffa03ed38b>] nfs4_proc_get_locations+0x9b/0x120 [nfsv4]
      [ 5123.103752] PGD 587b9067 PUD 3cbf5067 PMD 0
      [ 5123.104131] Oops: 0000 [#1]
      [ 5123.104529] Modules linked in: nfsv4(OE) nfs(OE) fscache(E) nfsd(OE) xfs libcrc32c iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi coretemp crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel ppdev vmw_balloon parport_pc parport i2c_piix4 shpchp auth_rpcgss nfs_acl vmw_vmci lockd grace sunrpc vmwgfx drm_kms_helper ttm drm mptspi serio_raw scsi_transport_spi e1000 mptscsih mptbase ata_generic pata_acpi [last unloaded: nfsd]
      [ 5123.105887] CPU: 0 PID: 15853 Comm: ::1-manager Tainted: G           OE   4.2.0-rc6+ #214
      [ 5123.106358] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 05/20/2014
      [ 5123.106860] task: ffff88007620f300 ti: ffff88005877c000 task.ti: ffff88005877c000
      [ 5123.107363] RIP: 0010:[<ffffffffa03ed38b>]  [<ffffffffa03ed38b>] nfs4_proc_get_locations+0x9b/0x120 [nfsv4]
      [ 5123.107909] RSP: 0018:ffff88005877fdb8  EFLAGS: 00010246
      [ 5123.108435] RAX: ffff880053f3bc00 RBX: ffff88006ce6c908 RCX: ffff880053a0d240
      [ 5123.108968] RDX: ffffea0000e6d940 RSI: ffff8800399a0000 RDI: ffff88006ce6c908
      [ 5123.109503] RBP: ffff88005877fe28 R08: ffffffff81c708a0 R09: 0000000000000000
      [ 5123.110045] R10: 00000000000001a2 R11: ffff88003ba7f5c8 R12: ffff880054c55800
      [ 5123.110618] R13: 0000000000000000 R14: ffff880053a0d240 R15: ffff880053a0d240
      [ 5123.111169] FS:  0000000000000000(0000) GS:ffffffff81c27000(0000) knlGS:0000000000000000
      [ 5123.111726] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
      [ 5123.112286] CR2: 0000000000000000 CR3: 0000000054cac000 CR4: 00000000001406f0
      [ 5123.112888] Stack:
      [ 5123.113458]  ffffea0000e6d940 ffff8800399a0000 00000000000167d0 0000000000000000
      [ 5123.114049]  0000000000000000 0000000000000000 0000000000000000 00000000a7ec82c6
      [ 5123.114662]  ffff88005877fe18 ffffea0000e6d940 ffff8800399a0000 ffff880054c55800
      [ 5123.115264] Call Trace:
      [ 5123.115868]  [<ffffffffa03fb44b>] nfs4_try_migration+0xbb/0x220 [nfsv4]
      [ 5123.116487]  [<ffffffffa03fcb3b>] nfs4_run_state_manager+0x4ab/0x7b0 [nfsv4]
      [ 5123.117104]  [<ffffffffa03fc690>] ? nfs4_do_reclaim+0x510/0x510 [nfsv4]
      [ 5123.117813]  [<ffffffff810a4527>] kthread+0xd7/0xf0
      [ 5123.118456]  [<ffffffff810a4450>] ? kthread_worker_fn+0x160/0x160
      [ 5123.119108]  [<ffffffff816d9cdf>] ret_from_fork+0x3f/0x70
      [ 5123.119723]  [<ffffffff810a4450>] ? kthread_worker_fn+0x160/0x160
      [ 5123.120329] Code: 4c 8b 6a 58 74 17 eb 52 48 8d 55 a8 89 c6 4c 89 e7 e8 4a b5 ff ff 8b 45 b0 85 c0 74 1c 4c 89 f9 48 8b 55 90 48 8b 75 98 48 89 df <41> ff 55 00 3d e8 d8 ff ff 41 89 c6 74 cf 48 8b 4d c8 65 48 33
      [ 5123.121643] RIP  [<ffffffffa03ed38b>] nfs4_proc_get_locations+0x9b/0x120 [nfsv4]
      [ 5123.122308]  RSP <ffff88005877fdb8>
      [ 5123.122942] CR2: 0000000000000000
      
      Fixes: ec011fe8 ("NFS: Introduce a vector of migration recovery ops")
      Cc: stable@vger.kernel.org # v3.13+
      Signed-off-by: default avatarKinglong Mee <kinglongmee@gmail.com>
      Signed-off-by: default avatarTrond Myklebust <trond.myklebust@primarydata.com>
      Signed-off-by: default avatarSasha Levin <sasha.levin@oracle.com>
      7730c1b9
    • NeilBrown's avatar
      NFSv4: don't set SETATTR for O_RDONLY|O_EXCL · 47bd9168
      NeilBrown authored
      [ Upstream commit efcbc04e ]
      
      It is unusual to combine the open flags O_RDONLY and O_EXCL, but
      it appears that libre-office does just that.
      
      [pid  3250] stat("/home/USER/.config", {st_mode=S_IFDIR|0700, st_size=8192, ...}) = 0
      [pid  3250] open("/home/USER/.config/libreoffice/4-suse/user/extensions/buildid", O_RDONLY|O_EXCL <unfinished ...>
      
      NFSv4 takes O_EXCL as a sign that a setattr command should be sent,
      probably to reset the timestamps.
      
      When it was an O_RDONLY open, the SETATTR command does not
      identify any actual attributes to change.
      If no delegation was provided to the open, the SETATTR uses the
      all-zeros stateid and the request is accepted (at least by the
      Linux NFS server - no harm, no foul).
      
      If a read-delegation was provided, this is used in the SETATTR
      request, and a Netapp filer will justifiably claim
      NFS4ERR_BAD_STATEID, which the Linux client takes as a sign
      to retry - indefinitely.
      
      So only treat O_EXCL specially if O_CREAT was also given.
      Signed-off-by: default avatarNeilBrown <neilb@suse.com>
      Cc: stable@vger.kernel.org
      Signed-off-by: default avatarTrond Myklebust <trond.myklebust@primarydata.com>
      Signed-off-by: default avatarSasha Levin <sasha.levin@oracle.com>
      47bd9168
    • Filipe Manana's avatar
      Btrfs: check if previous transaction aborted to avoid fs corruption · 04b4d54f
      Filipe Manana authored
      [ Upstream commit 1f9b8c8f ]
      
      While we are committing a transaction, it's possible the previous one is
      still finishing its commit and therefore we wait for it to finish first.
      However we were not checking if that previous transaction ended up getting
      aborted after we waited for it to commit, so we ended up committing the
      current transaction which can lead to fs corruption because the new
      superblock can point to trees that have had one or more nodes/leafs that
      were never durably persisted.
      The following sequence diagram exemplifies how this is possible:
      
                CPU 0                                                        CPU 1
      
        transaction N starts
      
        (...)
      
        btrfs_commit_transaction(N)
      
          cur_trans->state = TRANS_STATE_COMMIT_START;
          (...)
          cur_trans->state = TRANS_STATE_COMMIT_DOING;
          (...)
      
          cur_trans->state = TRANS_STATE_UNBLOCKED;
          root->fs_info->running_transaction = NULL;
      
                                                                    btrfs_start_transaction()
                                                                       --> starts transaction N + 1
      
          btrfs_write_and_wait_transaction(trans, root);
            --> starts writing all new or COWed ebs created
                at transaction N
      
                                                                    creates some new ebs, COWs some
                                                                    existing ebs but doesn't COW or
                                                                    deletes eb X
      
                                                                    btrfs_commit_transaction(N + 1)
                                                                      (...)
                                                                      cur_trans->state = TRANS_STATE_COMMIT_START;
                                                                      (...)
                                                                      wait_for_commit(root, prev_trans);
                                                                        --> prev_trans == transaction N
      
          btrfs_write_and_wait_transaction() continues
          writing ebs
             --> fails writing eb X, we abort transaction N
                 and set bit BTRFS_FS_STATE_ERROR on
                 fs_info->fs_state, so no new transactions
                 can start after setting that bit
      
             cleanup_transaction()
               btrfs_cleanup_one_transaction()
                 wakes up task at CPU 1
      
                                                                      continues, doesn't abort because
                                                                      cur_trans->aborted (transaction N + 1)
                                                                      is zero, and no checks for bit
                                                                      BTRFS_FS_STATE_ERROR in fs_info->fs_state
                                                                      are made
      
                                                                      btrfs_write_and_wait_transaction(trans, root);
                                                                        --> succeeds, no errors during writeback
      
                                                                      write_ctree_super(trans, root, 0);
                                                                        --> succeeds
                                                                        --> we have now a superblock that points us
                                                                            to some root that uses eb X, which was
                                                                            never written to disk
      
      In this scenario future attempts to read eb X from disk results in an
      error message like "parent transid verify failed on X wanted Y found Z".
      
      So fix this by aborting the current transaction if after waiting for the
      previous transaction we verify that it was aborted.
      
      Cc: stable@vger.kernel.org
      Signed-off-by: default avatarFilipe Manana <fdmanana@suse.com>
      Reviewed-by: default avatarJosef Bacik <jbacik@fb.com>
      Reviewed-by: default avatarLiu Bo <bo.li.liu@oracle.com>
      Signed-off-by: default avatarChris Mason <clm@fb.com>
      Signed-off-by: default avatarSasha Levin <sasha.levin@oracle.com>
      04b4d54f
    • Sakari Ailus's avatar
      [media] v4l: omap3isp: Fix sub-device power management code · bf4f1059
      Sakari Ailus authored
      [ Upstream commit 9d39f054 ]
      
      Commit 813f5c0a ("media: Change media device link_notify behaviour")
      modified the media controller link setup notification API and updated the
      OMAP3 ISP driver accordingly. As a side effect it introduced a bug by
      turning power on after setting the link instead of before. This results in
      sub-devices not being powered down in some cases when they should be. Fix
      it.
      
      Fixes: 813f5c0a [media] media: Change media device link_notify behaviour
      Signed-off-by: default avatarSakari Ailus <sakari.ailus@iki.fi>
      Cc: stable@vger.kernel.org # since v3.10
      Signed-off-by: default avatarLaurent Pinchart <laurent.pinchart@ideasonboard.com>
      Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@osg.samsung.com>
      Signed-off-by: default avatarSasha Levin <sasha.levin@oracle.com>
      bf4f1059