1. 13 Nov, 2014 40 commits
    • Benjamin Herrenschmidt's avatar
      drm/ast: Fix HW cursor image · 3055e72f
      Benjamin Herrenschmidt authored
      commit 1e99cfa8 upstream.
      
      The translation from the X driver to the KMS one typo'ed a couple
      of array indices, causing the HW cursor to look weird (blocky with
      leaking edge colors). This fixes it.
      Signed-off-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
      Signed-off-by: default avatarDave Airlie <airlied@redhat.com>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      3055e72f
    • Hans de Goede's avatar
      Input: i8042 - quirks for Fujitsu Lifebook A544 and Lifebook AH544 · 09cefff4
      Hans de Goede authored
      commit 993b3a3f upstream.
      
      These models need i8042.notimeout, otherwise the touchpad will not work.
      
      BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=69731
      BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1111138Signed-off-by: default avatarHans de Goede <hdegoede@redhat.com>
      Signed-off-by: default avatarDmitry Torokhov <dmitry.torokhov@gmail.com>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      09cefff4
    • Hans de Goede's avatar
      Input: i8042 - add noloop quirk for Asus X750LN · f16aa722
      Hans de Goede authored
      commit 9ff84a17 upstream.
      
      Without this the aux port does not get detected, and consequently the
      touchpad will not work.
      
      https://bugzilla.redhat.com/show_bug.cgi?id=1110011Signed-off-by: default avatarHans de Goede <hdegoede@redhat.com>
      Signed-off-by: default avatarDmitry Torokhov <dmitry.torokhov@gmail.com>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      f16aa722
    • Mikulas Patocka's avatar
      framebuffer: fix border color · 81332419
      Mikulas Patocka authored
      commit f74a289b upstream.
      
      The framebuffer code uses the current background color to fill the border
      when switching consoles, however, this results in inconsistent behavior.
      For example:
      - start Midnigh Commander
      - the border is black
      - switch to another console and switch back
      - the border is cyan
      - type something into the command line in mc
      - the border is cyan
      - switch to another console and switch back
      - the border is black
      - press F9 to go to menu
      - the border is black
      - switch to another console and switch back
      - the border is dark blue
      
      When switching to a console with Midnight Commander, the border is random
      color that was left selected by the slang subsystem.
      
      This patch fixes this inconsistency by always using black as the
      background color when switching consoles.
      Signed-off-by: default avatarMikulas Patocka <mpatocka@redhat.com>
      Signed-off-by: default avatarTomi Valkeinen <tomi.valkeinen@ti.com>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      81332419
    • Prarit Bhargava's avatar
      modules, lock around setting of MODULE_STATE_UNFORMED · 860ce424
      Prarit Bhargava authored
      commit d3051b48 upstream.
      
      A panic was seen in the following sitation.
      
      There are two threads running on the system. The first thread is a system
      monitoring thread that is reading /proc/modules. The second thread is
      loading and unloading a module (in this example I'm using my simple
      dummy-module.ko).  Note, in the "real world" this occurred with the qlogic
      driver module.
      
      When doing this, the following panic occurred:
      
       ------------[ cut here ]------------
       kernel BUG at kernel/module.c:3739!
       invalid opcode: 0000 [#1] SMP
       Modules linked in: binfmt_misc sg nfsv3 rpcsec_gss_krb5 nfsv4 dns_resolver nfs fscache intel_powerclamp coretemp kvm_intel kvm crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel aesni_intel lrw igb gf128mul glue_helper iTCO_wdt iTCO_vendor_support ablk_helper ptp sb_edac cryptd pps_core edac_core shpchp i2c_i801 pcspkr wmi lpc_ich ioatdma mfd_core dca ipmi_si nfsd ipmi_msghandler auth_rpcgss nfs_acl lockd sunrpc xfs libcrc32c sr_mod cdrom sd_mod crc_t10dif crct10dif_common mgag200 syscopyarea sysfillrect sysimgblt i2c_algo_bit drm_kms_helper ttm isci drm libsas ahci libahci scsi_transport_sas libata i2c_core dm_mirror dm_region_hash dm_log dm_mod [last unloaded: dummy_module]
       CPU: 37 PID: 186343 Comm: cat Tainted: GF          O--------------   3.10.0+ #7
       Hardware name: Intel Corporation S2600CP/S2600CP, BIOS RMLSDP.86I.00.29.D696.1311111329 11/11/2013
       task: ffff8807fd2d8000 ti: ffff88080fa7c000 task.ti: ffff88080fa7c000
       RIP: 0010:[<ffffffff810d64c5>]  [<ffffffff810d64c5>] module_flags+0xb5/0xc0
       RSP: 0018:ffff88080fa7fe18  EFLAGS: 00010246
       RAX: 0000000000000003 RBX: ffffffffa03b5200 RCX: 0000000000000000
       RDX: 0000000000001000 RSI: ffff88080fa7fe38 RDI: ffffffffa03b5000
       RBP: ffff88080fa7fe28 R08: 0000000000000010 R09: 0000000000000000
       R10: 0000000000000000 R11: 000000000000000f R12: ffffffffa03b5000
       R13: ffffffffa03b5008 R14: ffffffffa03b5200 R15: ffffffffa03b5000
       FS:  00007f6ae57ef740(0000) GS:ffff88101e7a0000(0000) knlGS:0000000000000000
       CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
       CR2: 0000000000404f70 CR3: 0000000ffed48000 CR4: 00000000001407e0
       DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
       DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
       Stack:
        ffffffffa03b5200 ffff8810101e4800 ffff88080fa7fe70 ffffffff810d666c
        ffff88081e807300 000000002e0f2fbf 0000000000000000 ffff88100f257b00
        ffffffffa03b5008 ffff88080fa7ff48 ffff8810101e4800 ffff88080fa7fee0
       Call Trace:
        [<ffffffff810d666c>] m_show+0x19c/0x1e0
        [<ffffffff811e4d7e>] seq_read+0x16e/0x3b0
        [<ffffffff812281ed>] proc_reg_read+0x3d/0x80
        [<ffffffff811c0f2c>] vfs_read+0x9c/0x170
        [<ffffffff811c1a58>] SyS_read+0x58/0xb0
        [<ffffffff81605829>] system_call_fastpath+0x16/0x1b
       Code: 48 63 c2 83 c2 01 c6 04 03 29 48 63 d2 eb d9 0f 1f 80 00 00 00 00 48 63 d2 c6 04 13 2d 41 8b 0c 24 8d 50 02 83 f9 01 75 b2 eb cb <0f> 0b 66 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 48 89 e5 41
       RIP  [<ffffffff810d64c5>] module_flags+0xb5/0xc0
        RSP <ffff88080fa7fe18>
      
          Consider the two processes running on the system.
      
          CPU 0 (/proc/modules reader)
          CPU 1 (loading/unloading module)
      
          CPU 0 opens /proc/modules, and starts displaying data for each module by
          traversing the modules list via fs/seq_file.c:seq_open() and
          fs/seq_file.c:seq_read().  For each module in the modules list, seq_read
          does
      
                  op->start()  <-- this is a pointer to m_start()
                  op->show()   <- this is a pointer to m_show()
                  op->stop()   <-- this is a pointer to m_stop()
      
          The m_start(), m_show(), and m_stop() module functions are defined in
          kernel/module.c. The m_start() and m_stop() functions acquire and release
          the module_mutex respectively.
      
          ie) When reading /proc/modules, the module_mutex is acquired and released
          for each module.
      
          m_show() is called with the module_mutex held.  It accesses the module
          struct data and attempts to write out module data.  It is in this code
          path that the above BUG_ON() warning is encountered, specifically m_show()
          calls
      
          static char *module_flags(struct module *mod, char *buf)
          {
                  int bx = 0;
      
                  BUG_ON(mod->state == MODULE_STATE_UNFORMED);
          ...
      
          The other thread, CPU 1, in unloading the module calls the syscall
          delete_module() defined in kernel/module.c.  The module_mutex is acquired
          for a short time, and then released.  free_module() is called without the
          module_mutex.  free_module() then sets mod->state = MODULE_STATE_UNFORMED,
          also without the module_mutex.  Some additional code is called and then the
          module_mutex is reacquired to remove the module from the modules list:
      
              /* Now we can delete it from the lists */
              mutex_lock(&module_mutex);
              stop_machine(__unlink_module, mod, NULL);
              mutex_unlock(&module_mutex);
      
      This is the sequence of events that leads to the panic.
      
      CPU 1 is removing dummy_module via delete_module().  It acquires the
      module_mutex, and then releases it.  CPU 1 has NOT set dummy_module->state to
      MODULE_STATE_UNFORMED yet.
      
      CPU 0, which is reading the /proc/modules, acquires the module_mutex and
      acquires a pointer to the dummy_module which is still in the modules list.
      CPU 0 calls m_show for dummy_module.  The check in m_show() for
      MODULE_STATE_UNFORMED passed for dummy_module even though it is being
      torn down.
      
      Meanwhile CPU 1, which has been continuing to remove dummy_module without
      holding the module_mutex, now calls free_module() and sets
      dummy_module->state to MODULE_STATE_UNFORMED.
      
      CPU 0 now calls module_flags() with dummy_module and ...
      
      static char *module_flags(struct module *mod, char *buf)
      {
              int bx = 0;
      
              BUG_ON(mod->state == MODULE_STATE_UNFORMED);
      
      and BOOM.
      
      Acquire and release the module_mutex lock around the setting of
      MODULE_STATE_UNFORMED in the teardown path, which should resolve the
      problem.
      
      Testing: In the unpatched kernel I can panic the system within 1 minute by
      doing
      
      while (true) do insmod dummy_module.ko; rmmod dummy_module.ko; done
      
      and
      
      while (true) do cat /proc/modules; done
      
      in separate terminals.
      
      In the patched kernel I was able to run just over one hour without seeing
      any issues.  I also verified the output of panic via sysrq-c and the output
      of /proc/modules looks correct for all three states for the dummy_module.
      
              dummy_module 12661 0 - Unloading 0xffffffffa03a5000 (OE-)
              dummy_module 12661 0 - Live 0xffffffffa03bb000 (OE)
              dummy_module 14015 1 - Loading 0xffffffffa03a5000 (OE+)
      Signed-off-by: default avatarPrarit Bhargava <prarit@redhat.com>
      Reviewed-by: default avatarOleg Nesterov <oleg@redhat.com>
      Signed-off-by: default avatarRusty Russell <rusty@rustcorp.com.au>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      860ce424
    • Alexey Khoroshilov's avatar
      dm log userspace: fix memory leak in dm_ulog_tfr_init failure path · 93232824
      Alexey Khoroshilov authored
      commit 56ec16cb upstream.
      
      If cn_add_callback() fails in dm_ulog_tfr_init(), it does not
      deallocate prealloced memory but calls cn_del_callback().
      
      Found by Linux Driver Verification project (linuxtesting.org).
      Signed-off-by: default avatarAlexey Khoroshilov <khoroshilov@ispras.ru>
      Reviewed-by: default avatarJonathan Brassow <jbrassow@redhat.com>
      Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      93232824
    • Mike Snitzer's avatar
      block: fix alignment_offset math that assumes io_min is a power-of-2 · 40e8412c
      Mike Snitzer authored
      commit b8839b8c upstream.
      
      The math in both blk_stack_limits() and queue_limit_alignment_offset()
      assume that a block device's io_min (aka minimum_io_size) is always a
      power-of-2.  Fix the math such that it works for non-power-of-2 io_min.
      
      This issue (of alignment_offset != 0) became apparent when testing
      dm-thinp with a thinp blocksize that matches a RAID6 stripesize of
      1280K.  Commit fdfb4c8c ("dm thin: set minimum_io_size to pool's data
      block size") unlocked the potential for alignment_offset != 0 due to
      the dm-thin-pool's io_min possibly being a non-power-of-2.
      Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
      Acked-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
      Signed-off-by: default avatarJens Axboe <axboe@fb.com>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      40e8412c
    • Lai Jiangshan's avatar
      drbd: compute the end before rb_insert_augmented() · 5fa353ff
      Lai Jiangshan authored
      commit 82cfb90b upstream.
      
      Commit 98683650 "Merge branch 'drbd-8.4_ed6' into
      for-3.8-drivers-drbd-8.4_ed6" switches to the new augment API, but the
      new API requires that the tree is augmented before rb_insert_augmented()
      is called, which is missing.
      
      So we add the augment-code to drbd_insert_interval() when it travels the
      tree up to down before rb_insert_augmented().  See the example in
      include/linux/interval_tree_generic.h or Documentation/rbtree.txt.
      
      drbd_insert_interval() may cancel the insertion when traveling, in this
      case, the just added augment-code does nothing before cancel since the
      @this node is already in the subtrees in this case.
      
      CC: Michel Lespinasse <walken@google.com>
      Signed-off-by: default avatarLai Jiangshan <laijs@cn.fujitsu.com>
      Signed-off-by: default avatarAndreas Gruenbacher <agruen@linbit.com>
      Signed-off-by: default avatarPhilipp Reisner <philipp.reisner@linbit.com>
      Signed-off-by: default avatarJens Axboe <axboe@fb.com>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      5fa353ff
    • Mikulas Patocka's avatar
      dm bufio: when done scanning return from __scan immediately · de91001e
      Mikulas Patocka authored
      commit 0e825862 upstream.
      
      When __scan frees the required number of buffer entries that the
      shrinker requested (nr_to_scan becomes zero) it must return.  Before
      this fix the __scan code exited only the inner loop and continued in the
      outer loop -- which could result in reduced performance due to extra
      buffers being freed (e.g. unnecessarily evicted thinp metadata needing
      to be synchronously re-read into bufio's cache).
      
      Also, move dm_bufio_cond_resched to __scan's inner loop, so that
      iterating the bufio client's lru lists doesn't result in scheduling
      latency.
      Reported-by: default avatarJoe Thornber <thornber@redhat.com>
      Signed-off-by: default avatarMikulas Patocka <mpatocka@redhat.com>
      Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      de91001e
    • Joe Thornber's avatar
      dm bufio: update last_accessed when relinking a buffer · 15188b07
      Joe Thornber authored
      commit eb76faf5 upstream.
      
      The 'last_accessed' member of the dm_buffer structure was only set when
      the the buffer was created.  This led to each buffer being discarded
      after dm_bufio_max_age time even if it was used recently.  In practice
      this resulted in all thinp metadata being evicted soon after being read
      -- this is particularly problematic for metadata intensive workloads
      like multithreaded small random IO.
      
      'last_accessed' is now updated each time the buffer is moved to the head
      of the LRU list, so the buffer is now properly discarded if it was not
      used in dm_bufio_max_age time.
      Signed-off-by: default avatarJoe Thornber <ejt@redhat.com>
      Signed-off-by: default avatarMikulas Patocka <mpatocka@redhat.com>
      Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      15188b07
    • Olaf Hering's avatar
      drm/cirrus: bind also to qemu-xen-traditional · 579cd311
      Olaf Hering authored
      commit c0c3e735 upstream.
      
      qemu as used by xend/xm toolstack uses a different subvendor id.
      Bind the drm driver also to this emulated card.
      Signed-off-by: default avatarOlaf Hering <olaf@aepfle.de>
      Signed-off-by: default avatarDave Airlie <airlied@redhat.com>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      579cd311
    • Roger Pau Monné's avatar
      xen-blkback: fix leak on grant map error path · e8dbfec2
      Roger Pau Monné authored
      commit 61cecca8 upstream.
      
      Fix leaking a page when a grant mapping has failed.
      Signed-off-by: default avatarRoger Pau Monné <roger.pau@citrix.com>
      Reported-and-Tested-by: default avatarTao Chen <boby.chen@huawei.com>
      Signed-off-by: default avatarKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      e8dbfec2
    • Michael S. Tsirkin's avatar
      virtio_pci: fix virtio spec compliance on restore · a5f37e6c
      Michael S. Tsirkin authored
      commit 6fbc198c upstream.
      
      On restore, virtio pci does the following:
      + set features
      + init vqs etc - device can be used at this point!
      + set ACKNOWLEDGE,DRIVER and DRIVER_OK status bits
      
      This is in violation of the virtio spec, which
      requires the following order:
      - ACKNOWLEDGE
      - DRIVER
      - init vqs
      - DRIVER_OK
      
      This behaviour will break with hypervisors that assume spec compliant
      behaviour.  It seems like a good idea to have this patch applied to
      stable branches to reduce the support butden for the hypervisors.
      
      Cc: Amit Shah <amit.shah@redhat.com>
      Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
      Signed-off-by: default avatarRusty Russell <rusty@rustcorp.com.au>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      a5f37e6c
    • Stephen Smalley's avatar
      selinux: fix inode security list corruption · ff6fe803
      Stephen Smalley authored
      commit 923190d3 upstream.
      
      sb_finish_set_opts() can race with inode_free_security()
      when initializing inode security structures for inodes
      created prior to initial policy load or by the filesystem
      during ->mount().   This appears to have always been
      a possible race, but commit 3dc91d43 ("SELinux:  Fix possible
      NULL pointer dereference in selinux_inode_permission()")
      made it more evident by immediately reusing the unioned
      list/rcu element  of the inode security structure for call_rcu()
      upon an inode_free_security().  But the underlying issue
      was already present before that commit as a possible use-after-free
      of isec.
      
      Shivnandan Kumar reported the list corruption and proposed
      a patch to split the list and rcu elements out of the union
      as separate fields of the inode_security_struct so that setting
      the rcu element would not affect the list element.  However,
      this would merely hide the issue and not truly fix the code.
      
      This patch instead moves up the deletion of the list entry
      prior to dropping the sbsec->isec_lock initially.  Then,
      if the inode is dropped subsequently, there will be no further
      references to the isec.
      Reported-by: default avatarShivnandan Kumar <shivnandan.k@samsung.com>
      Signed-off-by: default avatarStephen Smalley <sds@tycho.nsa.gov>
      Signed-off-by: default avatarPaul Moore <pmoore@redhat.com>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      ff6fe803
    • Valdis Kletnieks's avatar
      pstore: Fix duplicate {console,ftrace}-efi entries · 77bbc2f5
      Valdis Kletnieks authored
      commit d4bf205d upstream.
      
      The pstore filesystem still creates duplicate filename/inode pairs for
      some pstore types.  Add the id to the filename to prevent that.
      
      Before patch:
      
      [/sys/fs/pstore] ls -li
      total 0
      1250 -r--r--r--. 1 root root 67 Sep 29 17:09 console-efi
      1250 -r--r--r--. 1 root root 67 Sep 29 17:09 console-efi
      1250 -r--r--r--. 1 root root 67 Sep 29 17:09 console-efi
      1250 -r--r--r--. 1 root root 67 Sep 29 17:09 console-efi
      1250 -r--r--r--. 1 root root 67 Sep 29 17:09 console-efi
      1250 -r--r--r--. 1 root root 67 Sep 29 17:09 console-efi
      1250 -r--r--r--. 1 root root 67 Sep 29 17:09 console-efi
      1250 -r--r--r--. 1 root root 67 Sep 29 17:09 console-efi
      1250 -r--r--r--. 1 root root 67 Sep 29 17:09 console-efi
      
      After:
      
      [/sys/fs/pstore] ls -li
      total 0
      1232 -r--r--r--. 1 root root 148 Sep 29 17:09 console-efi-141202499100000
      1231 -r--r--r--. 1 root root  67 Sep 29 17:09 console-efi-141202499200000
      1230 -r--r--r--. 1 root root 148 Sep 29 17:44 console-efi-141202705400000
      1229 -r--r--r--. 1 root root  67 Sep 29 17:44 console-efi-141202705500000
      1228 -r--r--r--. 1 root root  67 Sep 29 20:42 console-efi-141203772600000
      1227 -r--r--r--. 1 root root 148 Sep 29 23:42 console-efi-141204854900000
      1226 -r--r--r--. 1 root root  67 Sep 29 23:42 console-efi-141204855000000
      1225 -r--r--r--. 1 root root 148 Sep 29 23:59 console-efi-141204954200000
      1224 -r--r--r--. 1 root root  67 Sep 29 23:59 console-efi-141204954400000
      Signed-off-by: default avatarValdis Kletnieks <valdis.kletnieks@vt.edu>
      Acked-by: default avatarKees Cook <keescook@chromium.org>
      Signed-off-by: default avatarTony Luck <tony.luck@intel.com>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      77bbc2f5
    • Chris Ball's avatar
      mfd: rtsx_pcr: Fix MSI enable error handling · 3d96e8ff
      Chris Ball authored
      commit 51529705 upstream.
      
      pci_enable_msi() can return failure with both positive and negative
      integers -- it returns 0 for success -- but is only tested here for
      "if (ret < 0)".  This causes us to try to use MSI on the RTS5249 SD
      reader in the Dell XPS 11 when enabling MSI failed, causing:
      
      [    1.737110] rtsx_pci: probe of 0000:05:00.0 failed with error -110
      Reported-by: default avatarD. Jared Dominguez <Jared_Dominguez@Dell.com>
      Tested-by: default avatarD. Jared Dominguez <Jared_Dominguez@Dell.com>
      Signed-off-by: default avatarChris Ball <chris@printf.net>
      Signed-off-by: default avatarLee Jones <lee.jones@linaro.org>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      3d96e8ff
    • Eric W. Biederman's avatar
      mnt: Prevent pivot_root from creating a loop in the mount tree · 365446fe
      Eric W. Biederman authored
      commit 0d082601 upstream.
      
      Andy Lutomirski recently demonstrated that when chroot is used to set
      the root path below the path for the new ``root'' passed to pivot_root
      the pivot_root system call succeeds and leaks mounts.
      
      In examining the code I see that starting with a new root that is
      below the current root in the mount tree will result in a loop in the
      mount tree after the mounts are detached and then reattached to one
      another.  Resulting in all kinds of ugliness including a leak of that
      mounts involved in the leak of the mount loop.
      
      Prevent this problem by ensuring that the new mount is reachable from
      the current root of the mount tree.
      
      [Added stable cc.  Fixes CVE-2014-7970.  --Andy]
      Reported-by: default avatarAndy Lutomirski <luto@amacapital.net>
      Reviewed-by: default avatarAndy Lutomirski <luto@amacapital.net>
      Link: http://lkml.kernel.org/r/87bnpmihks.fsf@x220.int.ebiederm.orgSigned-off-by: default avatar"Eric W. Biederman" <ebiederm@xmission.com>
      Signed-off-by: default avatarAndy Lutomirski <luto@amacapital.net>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      365446fe
    • Richard Genoud's avatar
      UBI: add missing kmem_cache_free() in process_pool_aeb error path · c7077ed4
      Richard Genoud authored
      commit 1bf1890e upstream.
      
      I ran into this error after a ubiupdatevol, because I forgot to backport
      e9110361 UBI: fix the volumes tree sorting criteria.
      
      UBI error: process_pool_aeb: orphaned volume in fastmap pool
      UBI error: ubi_scan_fastmap: Attach by fastmap failed, doing a full scan!
      kmem_cache_destroy ubi_ainf_peb_slab: Slab cache still has objects
      CPU: 0 PID: 1 Comm: swapper Not tainted 3.14.18-00053-gf05cac8dbf85 #1
      [<c000d298>] (unwind_backtrace) from [<c000baa8>] (show_stack+0x10/0x14)
      [<c000baa8>] (show_stack) from [<c01b7a68>] (destroy_ai+0x230/0x244)
      [<c01b7a68>] (destroy_ai) from [<c01b8fd4>] (ubi_attach+0x98/0x1ec)
      [<c01b8fd4>] (ubi_attach) from [<c01ade90>] (ubi_attach_mtd_dev+0x2b8/0x868)
      [<c01ade90>] (ubi_attach_mtd_dev) from [<c038b510>] (ubi_init+0x1dc/0x2ac)
      [<c038b510>] (ubi_init) from [<c0008860>] (do_one_initcall+0x94/0x140)
      [<c0008860>] (do_one_initcall) from [<c037aadc>] (kernel_init_freeable+0xe8/0x1b0)
      [<c037aadc>] (kernel_init_freeable) from [<c02730ac>] (kernel_init+0x8/0xe4)
      [<c02730ac>] (kernel_init) from [<c00093f0>] (ret_from_fork+0x14/0x24)
      UBI: scanning is finished
      
      Freeing the cache in the error path fixes the Slab error.
      
      Tested on at91sam9g35 (3.14.18+fastmap backports)
      Signed-off-by: default avatarRichard Genoud <richard.genoud@gmail.com>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      c7077ed4
    • Daniel Borkmann's avatar
      random: add and use memzero_explicit() for clearing data · 3b29acb3
      Daniel Borkmann authored
      commit d4c5efdb upstream.
      
      zatimend has reported that in his environment (3.16/gcc4.8.3/corei7)
      memset() calls which clear out sensitive data in extract_{buf,entropy,
      entropy_user}() in random driver are being optimized away by gcc.
      
      Add a helper memzero_explicit() (similarly as explicit_bzero() variants)
      that can be used in such cases where a variable with sensitive data is
      being cleared out in the end. Other use cases might also be in crypto
      code. [ I have put this into lib/string.c though, as it's always built-in
      and doesn't need any dependencies then. ]
      
      Fixes kernel bugzilla: 82041
      
      Reported-by: zatimend@hotmail.co.uk
      Signed-off-by: default avatarDaniel Borkmann <dborkman@redhat.com>
      Acked-by: default avatarHannes Frederic Sowa <hannes@stressinduktion.org>
      Cc: Alexey Dobriyan <adobriyan@gmail.com>
      Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      3b29acb3
    • Thorsten Knabe's avatar
      um: ubd: Fix for processes stuck in D state forever · 63550e4b
      Thorsten Knabe authored
      commit 2a236122 upstream.
      
      Starting with Linux 3.12 processes get stuck in D state forever in
      UserModeLinux under sync heavy workloads. This bug was introduced by
      commit 805f11a0 (um: ubd: Add REQ_FLUSH suppport).
      Fix bug by adding a check if FLUSH request was successfully submitted to
      the I/O thread and keeping the FLUSH request on the request queue on
      submission failures.
      
      Fixes: 805f11a0 (um: ubd: Add REQ_FLUSH suppport)
      Signed-off-by: default avatarThorsten Knabe <linux@thorsten-knabe.de>
      Signed-off-by: default avatarRichard Weinberger <richard@nod.at>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      63550e4b
    • Al Viro's avatar
      fix misuses of f_count() in ppp and netlink · ec84c5e8
      Al Viro authored
      commit 24dff96a upstream.
      
      we used to check for "nobody else could start doing anything with
      that opened file" by checking that refcount was 2 or less - one
      for descriptor table and one we'd acquired in fget() on the way to
      wherever we are.  That was race-prone (somebody else might have
      had a reference to descriptor table and do fget() just as we'd
      been checking) and it had become flat-out incorrect back when
      we switched to fget_light() on those codepaths - unlike fget(),
      it doesn't grab an extra reference unless the descriptor table
      is shared.  The same change allowed a race-free check, though -
      we are safe exactly when refcount is less than 2.
      
      It was a long time ago; pre-2.6.12 for ioctl() (the codepath leading
      to ppp one) and 2.6.17 for sendmsg() (netlink one).  OTOH,
      netlink hadn't grown that check until 3.9 and ppp used to live
      in drivers/net, not drivers/net/ppp until 3.1.  The bug existed
      well before that, though, and the same fix used to apply in old
      location of file.
      Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      ec84c5e8
    • Al Viro's avatar
      kill wbuf_queued/wbuf_dwork_lock · ca57f7e4
      Al Viro authored
      commit 99358a1c upstream.
      
      schedule_delayed_work() happening when the work is already pending is
      a cheap no-op.  Don't bother with ->wbuf_queued logics - it's both
      broken (cancelling ->wbuf_dwork leaves it set, as spotted by Jeff Harris)
      and pointless.  It's cheaper to let schedule_delayed_work() handle that
      case.
      Reported-by: default avatarJeff Harris <jefftharris@gmail.com>
      Tested-by: default avatarJeff Harris <jefftharris@gmail.com>
      Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      ca57f7e4
    • Al Viro's avatar
      missing data dependency barrier in prepend_name() · 1c4b9d08
      Al Viro authored
      commit 6d13f694 upstream.
      
      AFAICS, prepend_name() is broken on SMP alpha.  Disclaimer: I don't have
      SMP alpha boxen to reproduce it on.  However, it really looks like the race
      is real.
      
      CPU1: d_path() on /mnt/ramfs/<255-character>/foo
      CPU2: mv /mnt/ramfs/<255-character> /mnt/ramfs/<63-character>
      
      CPU2 does d_alloc(), which allocates an external name, stores the name there
      including terminating NUL, does smp_wmb() and stores its address in
      dentry->d_name.name.  It proceeds to d_add(dentry, NULL) and d_move()
      old dentry over to that.  ->d_name.name value ends up in that dentry.
      
      In the meanwhile, CPU1 gets to prepend_name() for that dentry.  It fetches
      ->d_name.name and ->d_name.len; the former ends up pointing to new name
      (64-byte kmalloc'ed array), the latter - 255 (length of the old name).
      Nothing to force the ordering there, and normally that would be OK, since we'd
      run into the terminating NUL and stop.  Except that it's alpha, and we'd need
      a data dependency barrier to guarantee that we see that store of NUL
      __d_alloc() has done.  In a similar situation dentry_cmp() would survive; it
      does explicit smp_read_barrier_depends() after fetching ->d_name.name.
      prepend_name() doesn't and it risks walking past the end of kmalloc'ed object
      and possibly oops due to taking a page fault in kernel mode.
      Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      1c4b9d08
    • Takashi Iwai's avatar
      ALSA: pcm: Zero-clear reserved fields of PCM status ioctl in compat mode · 12f36730
      Takashi Iwai authored
      commit 317168d0 upstream.
      
      In compat mode, we copy each field of snd_pcm_status struct but don't
      touch the reserved fields, and this leaves uninitialized values
      there.  Meanwhile the native ioctl does zero-clear the whole
      structure, so we should follow the same rule in compat mode, too.
      Reported-by: default avatarPierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
      Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      12f36730
    • Dmitry Kasatkin's avatar
      evm: check xattr value length and type in evm_inode_setxattr() · 54ae5738
      Dmitry Kasatkin authored
      commit 3b1deef6 upstream.
      
      evm_inode_setxattr() can be called with no value. The function does not
      check the length so that following command can be used to produce the
      kernel oops: setfattr -n security.evm FOO. This patch fixes it.
      
      Changes in v3:
      * there is no reason to return different error codes for EVM_XATTR_HMAC
        and non EVM_XATTR_HMAC. Remove unnecessary test then.
      
      Changes in v2:
      * testing for validity of xattr type
      
      [ 1106.396921] BUG: unable to handle kernel NULL pointer dereference at           (null)
      [ 1106.398192] IP: [<ffffffff812af7b8>] evm_inode_setxattr+0x2a/0x48
      [ 1106.399244] PGD 29048067 PUD 290d7067 PMD 0
      [ 1106.399953] Oops: 0000 [#1] SMP
      [ 1106.400020] Modules linked in: bridge stp llc evdev serio_raw i2c_piix4 button fuse
      [ 1106.400020] CPU: 0 PID: 3635 Comm: setxattr Not tainted 3.16.0-kds+ #2936
      [ 1106.400020] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
      [ 1106.400020] task: ffff8800291a0000 ti: ffff88002917c000 task.ti: ffff88002917c000
      [ 1106.400020] RIP: 0010:[<ffffffff812af7b8>]  [<ffffffff812af7b8>] evm_inode_setxattr+0x2a/0x48
      [ 1106.400020] RSP: 0018:ffff88002917fd50  EFLAGS: 00010246
      [ 1106.400020] RAX: 0000000000000000 RBX: ffff88002917fdf8 RCX: 0000000000000000
      [ 1106.400020] RDX: 0000000000000000 RSI: ffffffff818136d3 RDI: ffff88002917fdf8
      [ 1106.400020] RBP: ffff88002917fd68 R08: 0000000000000000 R09: 00000000003ec1df
      [ 1106.400020] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8800438a0a00
      [ 1106.400020] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
      [ 1106.400020] FS:  00007f7dfa7d7740(0000) GS:ffff88005da00000(0000) knlGS:0000000000000000
      [ 1106.400020] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
      [ 1106.400020] CR2: 0000000000000000 CR3: 000000003763e000 CR4: 00000000000006f0
      [ 1106.400020] Stack:
      [ 1106.400020]  ffff8800438a0a00 ffff88002917fdf8 0000000000000000 ffff88002917fd98
      [ 1106.400020]  ffffffff812a1030 ffff8800438a0a00 ffff88002917fdf8 0000000000000000
      [ 1106.400020]  0000000000000000 ffff88002917fde0 ffffffff8116d08a ffff88002917fdc8
      [ 1106.400020] Call Trace:
      [ 1106.400020]  [<ffffffff812a1030>] security_inode_setxattr+0x5d/0x6a
      [ 1106.400020]  [<ffffffff8116d08a>] vfs_setxattr+0x6b/0x9f
      [ 1106.400020]  [<ffffffff8116d1e0>] setxattr+0x122/0x16c
      [ 1106.400020]  [<ffffffff811687e8>] ? mnt_want_write+0x21/0x45
      [ 1106.400020]  [<ffffffff8114d011>] ? __sb_start_write+0x10f/0x143
      [ 1106.400020]  [<ffffffff811687e8>] ? mnt_want_write+0x21/0x45
      [ 1106.400020]  [<ffffffff811687c0>] ? __mnt_want_write+0x48/0x4f
      [ 1106.400020]  [<ffffffff8116d3e6>] SyS_setxattr+0x6e/0xb0
      [ 1106.400020]  [<ffffffff81529da9>] system_call_fastpath+0x16/0x1b
      [ 1106.400020] Code: c3 0f 1f 44 00 00 55 48 89 e5 41 55 49 89 d5 41 54 49 89 fc 53 48 89 f3 48 c7 c6 d3 36 81 81 48 89 df e8 18 22 04 00 85 c0 75 07 <41> 80 7d 00 02 74 0d 48 89 de 4c 89 e7 e8 5a fe ff ff eb 03 83
      [ 1106.400020] RIP  [<ffffffff812af7b8>] evm_inode_setxattr+0x2a/0x48
      [ 1106.400020]  RSP <ffff88002917fd50>
      [ 1106.400020] CR2: 0000000000000000
      [ 1106.428061] ---[ end trace ae08331628ba3050 ]---
      Reported-by: default avatarJan Kara <jack@suse.cz>
      Signed-off-by: default avatarDmitry Kasatkin <d.kasatkin@samsung.com>
      Signed-off-by: default avatarMimi Zohar <zohar@linux.vnet.ibm.com>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      54ae5738
    • Dexuan Cui's avatar
      x86, pageattr: Prevent overflow in slow_virt_to_phys() for X86_PAE · 0833c9e8
      Dexuan Cui authored
      commit d1cd1210 upstream.
      
      pte_pfn() returns a PFN of long (32 bits in 32-PAE), so "long <<
      PAGE_SHIFT" will overflow for PFNs above 4GB.
      
      Due to this issue, some Linux 32-PAE distros, running as guests on Hyper-V,
      with 5GB memory assigned, can't load the netvsc driver successfully and
      hence the synthetic network device can't work (we can use the kernel parameter
      mem=3000M to work around the issue).
      
      Cast pte_pfn() to phys_addr_t before shifting.
      
      Fixes: "commit d7656534: x86, mm: Create slow_virt_to_phys()"
      Signed-off-by: default avatarDexuan Cui <decui@microsoft.com>
      Cc: K. Y. Srinivasan <kys@microsoft.com>
      Cc: Haiyang Zhang <haiyangz@microsoft.com>
      Cc: gregkh@linuxfoundation.org
      Cc: linux-mm@kvack.org
      Cc: olaf@aepfle.de
      Cc: apw@canonical.com
      Cc: jasowang@redhat.com
      Cc: dave.hansen@intel.com
      Cc: riel@redhat.com
      Cc: stable@vger.kernel.org
      Link: http://lkml.kernel.org/r/1414580017-27444-1-git-send-email-decui@microsoft.comSigned-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      0833c9e8
    • Andy Lutomirski's avatar
      x86_64, entry: Filter RFLAGS.NT on entry from userspace · cb3a0a46
      Andy Lutomirski authored
      commit 8c7aa698 upstream.
      
      The NT flag doesn't do anything in long mode other than causing IRET
      to #GP.  Oddly, CPL3 code can still set NT using popf.
      
      Entry via hardware or software interrupt clears NT automatically, so
      the only relevant entries are fast syscalls.
      
      If user code causes kernel code to run with NT set, then there's at
      least some (small) chance that it could cause trouble.  For example,
      user code could cause a call to EFI code with NT set, and who knows
      what would happen?  Apparently some games on Wine sometimes do
      this (!), and, if an IRET return happens, they will segfault.  That
      segfault cannot be handled, because signal delivery fails, too.
      
      This patch programs the CPU to clear NT on entry via SYSCALL (both
      32-bit and 64-bit, by my reading of the AMD APM), and it clears NT
      in software on entry via SYSENTER.
      
      To save a few cycles, this borrows a trick from Jan Beulich in Xen:
      it checks whether NT is set before trying to clear it.  As a result,
      it seems to have very little effect on SYSENTER performance on my
      machine.
      
      There's another minor bug fix in here: it looks like the CFI
      annotations were wrong if CONFIG_AUDITSYSCALL=n.
      
      Testers beware: on Xen, SYSENTER with NT set turns into a GPF.
      
      I haven't touched anything on 32-bit kernels.
      
      The syscall mask change comes from a variant of this patch by Anish
      Bhatt.
      
      Note to stable maintainers: there is no known security issue here.
      A misguided program can set NT and cause the kernel to try and fail
      to deliver SIGSEGV, crashing the program.  This patch fixes Far Cry
      on Wine: https://bugs.winehq.org/show_bug.cgi?id=33275Reported-by: default avatarAnish Bhatt <anish@chelsio.com>
      Signed-off-by: default avatarAndy Lutomirski <luto@amacapital.net>
      Link: http://lkml.kernel.org/r/395749a5d39a29bd3e4b35899cf3a3c1340e5595.1412189265.git.luto@amacapital.netSigned-off-by: default avatarH. Peter Anvin <hpa@zytor.com>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      cb3a0a46
    • Oleg Nesterov's avatar
      x86, fpu: shift drop_init_fpu() from save_xstate_sig() to handle_signal() · 2a571858
      Oleg Nesterov authored
      commit 66463db4 upstream.
      
      save_xstate_sig()->drop_init_fpu() doesn't look right. setup_rt_frame()
      can fail after that, in this case the next setup_rt_frame() triggered
      by SIGSEGV won't save fpu simply because the old state was lost. This
      obviously mean that fpu won't be restored after sys_rt_sigreturn() from
      SIGSEGV handler.
      
      Shift drop_init_fpu() into !failed branch in handle_signal().
      
      Test-case (needs -O2):
      
      	#include <stdio.h>
      	#include <signal.h>
      	#include <unistd.h>
      	#include <sys/syscall.h>
      	#include <sys/mman.h>
      	#include <pthread.h>
      	#include <assert.h>
      
      	volatile double D;
      
      	void test(double d)
      	{
      		int pid = getpid();
      
      		for (D = d; D == d; ) {
      			/* sys_tkill(pid, SIGHUP); asm to avoid save/reload
      			 * fp regs around "C" call */
      			asm ("" : : "a"(200), "D"(pid), "S"(1));
      			asm ("syscall" : : : "ax");
      		}
      
      		printf("ERR!!\n");
      	}
      
      	void sigh(int sig)
      	{
      	}
      
      	char altstack[4096 * 10] __attribute__((aligned(4096)));
      
      	void *tfunc(void *arg)
      	{
      		for (;;) {
      			mprotect(altstack, sizeof(altstack), PROT_READ);
      			mprotect(altstack, sizeof(altstack), PROT_READ|PROT_WRITE);
      		}
      	}
      
      	int main(void)
      	{
      		stack_t st = {
      			.ss_sp = altstack,
      			.ss_size = sizeof(altstack),
      			.ss_flags = SS_ONSTACK,
      		};
      
      		struct sigaction sa = {
      			.sa_handler = sigh,
      		};
      
      		pthread_t pt;
      
      		sigaction(SIGSEGV, &sa, NULL);
      		sigaltstack(&st, NULL);
      		sa.sa_flags = SA_ONSTACK;
      		sigaction(SIGHUP, &sa, NULL);
      
      		pthread_create(&pt, NULL, tfunc, NULL);
      
      		test(123.456);
      		return 0;
      	}
      Reported-by: default avatarBean Anderson <bean@azulsystems.com>
      Signed-off-by: default avatarOleg Nesterov <oleg@redhat.com>
      Link: http://lkml.kernel.org/r/20140902175713.GA21646@redhat.comSigned-off-by: default avatarH. Peter Anvin <hpa@linux.intel.com>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      2a571858
    • Oleg Nesterov's avatar
      x86, fpu: __restore_xstate_sig()->math_state_restore() needs preempt_disable() · 03f43efc
      Oleg Nesterov authored
      commit df24fb85 upstream.
      
      Add preempt_disable() + preempt_enable() around math_state_restore() in
      __restore_xstate_sig(). Otherwise __switch_to() after __thread_fpu_begin()
      can overwrite fpu->state we are going to restore.
      Signed-off-by: default avatarOleg Nesterov <oleg@redhat.com>
      Link: http://lkml.kernel.org/r/20140902175717.GA21649@redhat.comReviewed-by: default avatarSuresh Siddha <sbsiddha@gmail.com>
      Signed-off-by: default avatarH. Peter Anvin <hpa@linux.intel.com>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      03f43efc
    • Ben Hutchings's avatar
      x86: Reject x32 executables if x32 ABI not supported · 19ad5dfd
      Ben Hutchings authored
      commit 0e6d3112 upstream.
      
      It is currently possible to execve() an x32 executable on an x86_64
      kernel that has only ia32 compat enabled.  However all its syscalls
      will fail, even _exit().  This usually causes it to segfault.
      
      Change the ELF compat architecture check so that x32 executables are
      rejected if we don't support the x32 ABI.
      Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
      Link: http://lkml.kernel.org/r/1410120305.6822.9.camel@decadent.org.ukSigned-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      19ad5dfd
    • Jan Kara's avatar
      vfs: fix data corruption when blocksize < pagesize for mmaped data · 39766903
      Jan Kara authored
      commit 90a80202 upstream.
      
      ->page_mkwrite() is used by filesystems to allocate blocks under a page
      which is becoming writeably mmapped in some process' address space. This
      allows a filesystem to return a page fault if there is not enough space
      available, user exceeds quota or similar problem happens, rather than
      silently discarding data later when writepage is called.
      
      However VFS fails to call ->page_mkwrite() in all the cases where
      filesystems need it when blocksize < pagesize. For example when
      blocksize = 1024, pagesize = 4096 the following is problematic:
        ftruncate(fd, 0);
        pwrite(fd, buf, 1024, 0);
        map = mmap(NULL, 1024, PROT_WRITE, MAP_SHARED, fd, 0);
        map[0] = 'a';       ----> page_mkwrite() for index 0 is called
        ftruncate(fd, 10000); /* or even pwrite(fd, buf, 1, 10000) */
        mremap(map, 1024, 10000, 0);
        map[4095] = 'a';    ----> no page_mkwrite() called
      
      At the moment ->page_mkwrite() is called, filesystem can allocate only
      one block for the page because i_size == 1024. Otherwise it would create
      blocks beyond i_size which is generally undesirable. But later at
      ->writepage() time, we also need to store data at offset 4095 but we
      don't have block allocated for it.
      
      This patch introduces a helper function filesystems can use to have
      ->page_mkwrite() called at all the necessary moments.
      Signed-off-by: default avatarJan Kara <jack@suse.cz>
      Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      39766903
    • Artem Bityutskiy's avatar
      UBIFS: fix free log space calculation · 4f111bbc
      Artem Bityutskiy authored
      commit ba29e721 upstream.
      
      Hu (hujianyang <hujianyang@huawei.com>) discovered an issue in the
      'empty_log_bytes()' function, which calculates how many bytes are left in the
      log:
      
      "
      If 'c->lhead_lnum + 1 == c->ltail_lnum' and 'c->lhead_offs == c->leb_size', 'h'
      would equalent to 't' and 'empty_log_bytes()' would return 'c->log_bytes'
      instead of 0.
      "
      
      At this point it is not clear what would be the consequences of this, and
      whether this may lead to any problems, but this patch addresses the issue just
      in case.
      Tested-by: default avatarhujianyang <hujianyang@huawei.com>
      Reported-by: default avatarhujianyang <hujianyang@huawei.com>
      Signed-off-by: default avatarArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      4f111bbc
    • Artem Bityutskiy's avatar
      UBIFS: fix a race condition · c52a2795
      Artem Bityutskiy authored
      commit 052c2807 upstream.
      
      Hu (hujianyang@huawei.com) discovered a race condition which may lead to a
      situation when UBIFS is unable to mount the file-system after an unclean
      reboot. The problem is theoretical, though.
      
      In UBIFS, we have the log, which basically a set of LEBs in a certain area. The
      log has the tail and the head.
      
      Every time user writes data to the file-system, the UBIFS journal grows, and
      the log grows as well, because we append new reference nodes to the head of the
      log. So the head moves forward all the time, while the log tail stays at the
      same position.
      
      At any time, the UBIFS master node points to the tail of the log. When we mount
      the file-system, we scan the log, and we always start from its tail, because
      this is where the master node points to. The only occasion when the tail of the
      log changes is the commit operation.
      
      The commit operation has 2 phases - "commit start" and "commit end". The former
      is relatively short, and does not involve much I/O. During this phase we mostly
      just build various in-memory lists of the things which have to be written to
      the flash media during "commit end" phase.
      
      During the commit start phase, what we do is we "clean" the log. Indeed, the
      commit operation will index all the data in the journal, so the entire journal
      "disappears", and therefore the data in the log become unneeded. So we just
      move the head of the log to the next LEB, and write the CS node there. This LEB
      will be the tail of the new log when the commit operation finishes.
      
      When the "commit start" phase finishes, users may write more data to the
      file-system, in parallel with the ongoing "commit end" operation. At this point
      the log tail was not changed yet, it is the same as it had been before we
      started the commit. The log head keeps moving forward, though.
      
      The commit operation now needs to write the new master node, and the new master
      node should point to the new log tail. After this the LEBs between the old log
      tail and the new log tail can be unmapped and re-used again.
      
      And here is the possible problem. We do 2 operations: (a) We first update the
      log tail position in memory (see 'ubifs_log_end_commit()'). (b) And then we
      write the master node (see the big lock of code in 'do_commit()').
      
      But nothing prevents the log head from moving forward between (a) and (b), and
      the log head may "wrap" now to the old log tail. And when the "wrap" happens,
      the contends of the log tail gets erased. Now a power cut happens and we are in
      trouble. We end up with the old master node pointing to the old tail, which was
      erased. And replay fails because it expects the master node to point to the
      correct log tail at all times.
      
      This patch merges the abovementioned (a) and (b) operations by moving the master
      node change code to the 'ubifs_log_end_commit()' function, so that it runs with
      the log mutex locked, which will prevent the log from being changed benween
      operations (a) and (b).
      Reported-by: default avatarhujianyang <hujianyang@huawei.com>
      Tested-by: default avatarhujianyang <hujianyang@huawei.com>
      Signed-off-by: default avatarArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      c52a2795
    • Artem Bityutskiy's avatar
      UBIFS: remove mst_mutex · c2e13039
      Artem Bityutskiy authored
      commit 07e19dff upstream.
      
      The 'mst_mutex' is not needed since because 'ubifs_write_master()' is only
      called on the mount path and commit path. The mount path is sequential and
      there is no parallelism, and the commit path is also serialized - there is only
      one commit going on at a time.
      Signed-off-by: default avatarArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      c2e13039
    • Eric Rannaud's avatar
      fs: allow open(dir, O_TMPFILE|..., 0) with mode 0 · e54fc4ed
      Eric Rannaud authored
      commit 69a91c23 upstream.
      
      The man page for open(2) indicates that when O_CREAT is specified, the
      'mode' argument applies only to future accesses to the file:
      
      	Note that this mode applies only to future accesses of the newly
      	created file; the open() call that creates a read-only file
      	may well return a read/write file descriptor.
      
      The man page for open(2) implies that 'mode' is treated identically by
      O_CREAT and O_TMPFILE.
      
      O_TMPFILE, however, behaves differently:
      
      	int fd = open("/tmp", O_TMPFILE | O_RDWR, 0);
      	assert(fd == -1);
      	assert(errno == EACCES);
      
      	int fd = open("/tmp", O_TMPFILE | O_RDWR, 0600);
      	assert(fd > 0);
      
      For O_CREAT, do_last() sets acc_mode to MAY_OPEN only:
      
      	if (*opened & FILE_CREATED) {
      		/* Don't check for write permission, don't truncate */
      		open_flag &= ~O_TRUNC;
      		will_truncate = false;
      		acc_mode = MAY_OPEN;
      		path_to_nameidata(path, nd);
      		goto finish_open_created;
      	}
      
      But for O_TMPFILE, do_tmpfile() passes the full op->acc_mode to
      may_open().
      
      This patch lines up the behavior of O_TMPFILE with O_CREAT. After the
      inode is created, may_open() is called with acc_mode = MAY_OPEN, in
      do_tmpfile().
      
      A different, but related glibc bug revealed the discrepancy:
      https://sourceware.org/bugzilla/show_bug.cgi?id=17523
      
      The glibc lazily loads the 'mode' argument of open() and openat() using
      va_arg() only if O_CREAT is present in 'flags' (to support both the 2
      argument and the 3 argument forms of open; same idea for openat()).
      However, the glibc ignores the 'mode' argument if O_TMPFILE is in
      'flags'.
      
      On x86_64, for open(), it magically works anyway, as 'mode' is in
      RDX when entering open(), and is still in RDX on SYSCALL, which is where
      the kernel looks for the 3rd argument of a syscall.
      
      But openat() is not quite so lucky: 'mode' is in RCX when entering the
      glibc wrapper for openat(), while the kernel looks for the 4th argument
      of a syscall in R10. Indeed, the syscall calling convention differs from
      the regular calling convention in this respect on x86_64. So the kernel
      sees mode = 0 when trying to use glibc openat() with O_TMPFILE, and
      fails with EACCES.
      Signed-off-by: default avatarEric Rannaud <e@nanocritical.com>
      Acked-by: default avatarAndy Lutomirski <luto@amacapital.net>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      e54fc4ed
    • Tetsuo Handa's avatar
      fs: Fix theoretical division by 0 in super_cache_scan(). · b44a6e33
      Tetsuo Handa authored
      commit 475d0db7 upstream.
      
      total_objects could be 0 and is used as a denom.
      
      While total_objects is a "long", total_objects == 0 unlikely happens for
      3.12 and later kernels because 32-bit architectures would not be able to
      hold (1 << 32) objects. However, total_objects == 0 may happen for kernels
      between 3.1 and 3.11 because total_objects in prune_super() was an "int"
      and (e.g.) x86_64 architecture might be able to hold (1 << 32) objects.
      Signed-off-by: default avatarTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
      Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
      Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      b44a6e33
    • Mikulas Patocka's avatar
      fs: make cont_expand_zero interruptible · b99b3db3
      Mikulas Patocka authored
      commit c2ca0fcd upstream.
      
      This patch makes it possible to kill a process looping in
      cont_expand_zero. A process may spend a lot of time in this function, so
      it is desirable to be able to kill it.
      
      It happened to me that I wanted to copy a piece data from the disk to a
      file. By mistake, I used the "seek" parameter to dd instead of "skip". Due
      to the "seek" parameter, dd attempted to extend the file and became stuck
      doing so - the only possibility was to reset the machine or wait many
      hours until the filesystem runs out of space and cont_expand_zero fails.
      We need this patch to be able to terminate the process.
      Signed-off-by: default avatarMikulas Patocka <mpatocka@redhat.com>
      Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      b99b3db3
    • Roger Tseng's avatar
      mmc: rtsx_pci_sdmmc: fix incorrect last byte in R2 response · 87394e73
      Roger Tseng authored
      commit d1419d50 upstream.
      
      Current code erroneously fill the last byte of R2 response with an undefined
      value. In addition, the controller actually 'offloads' the last byte
      (CRC7, end bit) while receiving R2 response and thus it's impossible to get the
      actual value. This could cause mmc stack to obtain inconsistent CID from the
      same card after resume and misidentify it as a different card.
      
      Fix by assigning dummy CRC and end bit: {7'b0, 1} = 0x1 to the last byte of R2.
      
      Fixes: ff984e57 ("mmc: Add realtek pcie sdmmc host driver")
      Signed-off-by: default avatarRoger Tseng <rogerable@realtek.com>
      Signed-off-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      87394e73
    • Daniel Mack's avatar
      ASoC: soc-dapm: fix use after free · 9e5e1810
      Daniel Mack authored
      commit e5092c96 upstream.
      
      Coverity spotted the following possible use-after-free condition in
      dapm_create_or_share_mixmux_kcontrol():
      
      If kcontrol is NULL, and (wname_in_long_name && kcname_in_long_name)
      validates to true, 'name' will be set to an allocated string, and be
      freed a few lines later via the 'long_name' alias. 'name', however,
      is used by dev_err() in case snd_ctl_add() fails.
      
      Fix this by adding a jump label that frees 'long_name' at the end of
      the function.
      Signed-off-by: default avatarDaniel Mack <daniel@zonque.org>
      Signed-off-by: default avatarMark Brown <broonie@kernel.org>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      9e5e1810
    • Ondrej Zary's avatar
      libata-sff: Fix controllers with no ctl port · d525cbdb
      Ondrej Zary authored
      commit 6d8ca28f upstream.
      
      Currently, ata_sff_softreset is skipped for controllers with no ctl port.
      But that also skips ata_sff_dev_classify required for device detection.
      This means that libata is currently broken on controllers with no ctl port.
      
      No device connected:
      [    1.872480] pata_isapnp 01:01.02: activated
      [    1.889823] scsi2 : pata_isapnp
      [    1.890109] ata3: PATA max PIO0 cmd 0x1e8 ctl 0x0 irq 11
      [    6.888110] ata3.01: qc timeout (cmd 0xec)
      [    6.888179] ata3.01: failed to IDENTIFY (I/O error, err_mask=0x5)
      [   16.888085] ata3.01: qc timeout (cmd 0xec)
      [   16.888147] ata3.01: failed to IDENTIFY (I/O error, err_mask=0x5)
      [   46.888086] ata3.01: qc timeout (cmd 0xec)
      [   46.888148] ata3.01: failed to IDENTIFY (I/O error, err_mask=0x5)
      [   51.888100] ata3.00: qc timeout (cmd 0xec)
      [   51.888160] ata3.00: failed to IDENTIFY (I/O error, err_mask=0x5)
      [   61.888079] ata3.00: qc timeout (cmd 0xec)
      [   61.888141] ata3.00: failed to IDENTIFY (I/O error, err_mask=0x5)
      [   91.888089] ata3.00: qc timeout (cmd 0xec)
      [   91.888152] ata3.00: failed to IDENTIFY (I/O error, err_mask=0x5)
      
      ATAPI device connected:
      [    1.882061] pata_isapnp 01:01.02: activated
      [    1.893430] scsi2 : pata_isapnp
      [    1.893719] ata3: PATA max PIO0 cmd 0x1e8 ctl 0x0 irq 11
      [    6.892107] ata3.01: qc timeout (cmd 0xec)
      [    6.892171] ata3.01: failed to IDENTIFY (I/O error, err_mask=0x5)
      [   16.892079] ata3.01: qc timeout (cmd 0xec)
      [   16.892138] ata3.01: failed to IDENTIFY (I/O error, err_mask=0x5)
      [   46.892079] ata3.01: qc timeout (cmd 0xec)
      [   46.892138] ata3.01: failed to IDENTIFY (I/O error, err_mask=0x5)
      [   46.908586] ata3.00: ATAPI: ACER CD-767E/O, V1.5X, max PIO2, CDB intr
      [   46.924570] ata3.00: configured for PIO0 (device error ignored)
      [   46.926295] scsi 2:0:0:0: CD-ROM            ACER     CD-767E/O        1.5X PQ: 0 ANSI: 5
      [   46.984519] sr0: scsi3-mmc drive: 6x/6x xa/form2 tray
      [   46.984592] cdrom: Uniform CD-ROM driver Revision: 3.20
      
      So don't skip ata_sff_softreset, just skip the reset part of ata_bus_softreset
      if the ctl port is not available.
      
      This makes IDE port on ES968 behave correctly:
      
      No device connected:
      [    4.670888] pata_isapnp 01:01.02: activated
      [    4.673207] scsi host2: pata_isapnp
      [    4.673675] ata3: PATA max PIO0 cmd 0x1e8 ctl 0x0 irq 11
      [    7.081840] Adding 2541652k swap on /dev/sda2.  Priority:-1 extents:1 across:2541652k
      
      ATAPI device connected:
      [    4.704362] pata_isapnp 01:01.02: activated
      [    4.706620] scsi host2: pata_isapnp
      [    4.706877] ata3: PATA max PIO0 cmd 0x1e8 ctl 0x0 irq 11
      [    4.872782] ata3.00: ATAPI: ACER CD-767E/O, V1.5X, max PIO2, CDB intr
      [    4.888673] ata3.00: configured for PIO0 (device error ignored)
      [    4.893984] scsi 2:0:0:0: CD-ROM            ACER     CD-767E/O        1.5X PQ: 0 ANSI: 5
      [    7.015578] Adding 2541652k swap on /dev/sda2.  Priority:-1 extents:1 across:2541652k
      Signed-off-by: default avatarOndrej Zary <linux@rainbow-software.org>
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
      d525cbdb