1. 09 May, 2016 31 commits
    • Dmitry V. Levin's avatar
      parisc: fix a bug when syscall number of tracee is __NR_Linux_syscalls · bd505de8
      Dmitry V. Levin authored
      commit f0b22d1b upstream.
      
      Do not load one entry beyond the end of the syscall table when the
      syscall number of a traced process equals to __NR_Linux_syscalls.
      Similar bug with regular processes was fixed by commit 3bb457af
      ("[PARISC] Fix bug when syscall nr is __NR_Linux_syscalls").
      
      This bug was found by strace test suite.
      Signed-off-by: default avatarDmitry V. Levin <ldv@altlinux.org>
      Acked-by: default avatarHelge Deller <deller@gmx.de>
      Signed-off-by: default avatarHelge Deller <deller@gmx.de>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      bd505de8
    • Chen Yu's avatar
      x86/tsc: Read all ratio bits from MSR_PLATFORM_INFO · 0410f29d
      Chen Yu authored
      commit 886123fb upstream.
      
      Currently we read the tsc radio: ratio = (MSR_PLATFORM_INFO >> 8) & 0x1f;
      
      Thus we get bit 8-12 of MSR_PLATFORM_INFO, however according to the SDM
      (35.5), the ratio bits are bit 8-15.
      
      Ignoring the upper bits can result in an incorrect tsc ratio, which causes the
      TSC calibration and the Local APIC timer frequency to be incorrect.
      
      Fix this problem by masking 0xff instead.
      
      [ tglx: Massaged changelog ]
      
      Fixes: 7da7c156 "x86, tsc: Add static (MSR) TSC calibration on Intel Atom SoCs"
      Signed-off-by: default avatarChen Yu <yu.c.chen@intel.com>
      Cc: "Rafael J. Wysocki" <rafael@kernel.org>
      Cc: Bin Gao <bin.gao@intel.com>
      Cc: Len Brown <lenb@kernel.org>
      Link: http://lkml.kernel.org/r/1462505619-5516-1-git-send-email-yu.c.chen@intel.comSigned-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      0410f29d
    • Hugh Dickins's avatar
      mm, cma: prevent nr_isolated_* counters from going negative · 1965a781
      Hugh Dickins authored
      commit 14af4a5e upstream.
      
      /proc/sys/vm/stat_refresh warns nr_isolated_anon and nr_isolated_file go
      increasingly negative under compaction: which would add delay when
      should be none, or no delay when should delay.  The bug in compaction
      was due to a recent mmotm patch, but much older instance of the bug was
      also noticed in isolate_migratepages_range() which is used for CMA and
      gigantic hugepage allocations.
      
      The bug is caused by putback_movable_pages() in an error path
      decrementing the isolated counters without them being previously
      incremented by acct_isolated().  Fix isolate_migratepages_range() by
      removing the error-path putback, thus reaching acct_isolated() with
      migratepages still isolated, and leaving putback to caller like most
      other places do.
      
      Fixes: edc2ca61 ("mm, compaction: move pageblock checks up from isolate_migratepages_range()")
      [vbabka@suse.cz: expanded the changelog]
      Signed-off-by: default avatarHugh Dickins <hughd@google.com>
      Signed-off-by: default avatarVlastimil Babka <vbabka@suse.cz>
      Acked-by: default avatarJoonsoo Kim <iamjoonsoo.kim@lge.com>
      Cc: Michal Hocko <mhocko@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 avatarKamal Mostafa <kamal@canonical.com>
      1965a781
    • Eric W. Biederman's avatar
      propogate_mnt: Handle the first propogated copy being a slave · ea834f56
      Eric W. Biederman authored
      commit 5ec0811d upstream.
      
      When the first propgated copy was a slave the following oops would result:
      > BUG: unable to handle kernel NULL pointer dereference at 0000000000000010
      > IP: [<ffffffff811fba4e>] propagate_one+0xbe/0x1c0
      > PGD bacd4067 PUD bac66067 PMD 0
      > Oops: 0000 [#1] SMP
      > Modules linked in:
      > CPU: 1 PID: 824 Comm: mount Not tainted 4.6.0-rc5userns+ #1523
      > Hardware name: Bochs Bochs, BIOS Bochs 01/01/2007
      > task: ffff8800bb0a8000 ti: ffff8800bac3c000 task.ti: ffff8800bac3c000
      > RIP: 0010:[<ffffffff811fba4e>]  [<ffffffff811fba4e>] propagate_one+0xbe/0x1c0
      > RSP: 0018:ffff8800bac3fd38  EFLAGS: 00010283
      > RAX: 0000000000000000 RBX: ffff8800bb77ec00 RCX: 0000000000000010
      > RDX: 0000000000000000 RSI: ffff8800bb58c000 RDI: ffff8800bb58c480
      > RBP: ffff8800bac3fd48 R08: 0000000000000001 R09: 0000000000000000
      > R10: 0000000000001ca1 R11: 0000000000001c9d R12: 0000000000000000
      > R13: ffff8800ba713800 R14: ffff8800bac3fda0 R15: ffff8800bb77ec00
      > FS:  00007f3c0cd9b7e0(0000) GS:ffff8800bfb00000(0000) knlGS:0000000000000000
      > CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
      > CR2: 0000000000000010 CR3: 00000000bb79d000 CR4: 00000000000006e0
      > Stack:
      >  ffff8800bb77ec00 0000000000000000 ffff8800bac3fd88 ffffffff811fbf85
      >  ffff8800bac3fd98 ffff8800bb77f080 ffff8800ba713800 ffff8800bb262b40
      >  0000000000000000 0000000000000000 ffff8800bac3fdd8 ffffffff811f1da0
      > Call Trace:
      >  [<ffffffff811fbf85>] propagate_mnt+0x105/0x140
      >  [<ffffffff811f1da0>] attach_recursive_mnt+0x120/0x1e0
      >  [<ffffffff811f1ec3>] graft_tree+0x63/0x70
      >  [<ffffffff811f1f6b>] do_add_mount+0x9b/0x100
      >  [<ffffffff811f2c1a>] do_mount+0x2aa/0xdf0
      >  [<ffffffff8117efbe>] ? strndup_user+0x4e/0x70
      >  [<ffffffff811f3a45>] SyS_mount+0x75/0xc0
      >  [<ffffffff8100242b>] do_syscall_64+0x4b/0xa0
      >  [<ffffffff81988f3c>] entry_SYSCALL64_slow_path+0x25/0x25
      > Code: 00 00 75 ec 48 89 0d 02 22 22 01 8b 89 10 01 00 00 48 89 05 fd 21 22 01 39 8e 10 01 00 00 0f 84 e0 00 00 00 48 8b 80 d8 00 00 00 <48> 8b 50 10 48 89 05 df 21 22 01 48 89 15 d0 21 22 01 8b 53 30
      > RIP  [<ffffffff811fba4e>] propagate_one+0xbe/0x1c0
      >  RSP <ffff8800bac3fd38>
      > CR2: 0000000000000010
      > ---[ end trace 2725ecd95164f217 ]---
      
      This oops happens with the namespace_sem held and can be triggered by
      non-root users.  An all around not pleasant experience.
      
      To avoid this scenario when finding the appropriate source mount to
      copy stop the walk up the mnt_master chain when the first source mount
      is encountered.
      
      Further rewrite the walk up the last_source mnt_master chain so that
      it is clear what is going on.
      
      The reason why the first source mount is special is that it it's
      mnt_parent is not a mount in the dest_mnt propagation tree, and as
      such termination conditions based up on the dest_mnt mount propgation
      tree do not make sense.
      
      To avoid other kinds of confusion last_dest is not changed when
      computing last_source.  last_dest is only used once in propagate_one
      and that is above the point of the code being modified, so changing
      the global variable is meaningless and confusing.
      
      fixes: f2ebb3a9 ("smarter propagate_mnt()")
      Reported-by: default avatarTycho Andersen <tycho.andersen@canonical.com>
      Reviewed-by: default avatarSeth Forshee <seth.forshee@canonical.com>
      Tested-by: default avatarSeth Forshee <seth.forshee@canonical.com>
      Signed-off-by: default avatar"Eric W. Biederman" <ebiederm@xmission.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      ea834f56
    • Maxim Patlasov's avatar
      fs/pnode.c: treat zero mnt_group_id-s as unequal · 50d0aee1
      Maxim Patlasov authored
      commit 7ae8fd03 upstream.
      
      propagate_one(m) calculates "type" argument for copy_tree() like this:
      
      >    if (m->mnt_group_id == last_dest->mnt_group_id) {
      >        type = CL_MAKE_SHARED;
      >    } else {
      >        type = CL_SLAVE;
      >        if (IS_MNT_SHARED(m))
      >           type |= CL_MAKE_SHARED;
      >   }
      
      The "type" argument then governs clone_mnt() behavior with respect to flags
      and mnt_master of new mount. When we iterate through a slave group, it is
      possible that both current "m" and "last_dest" are not shared (although,
      both are slaves, i.e. have non-NULL mnt_master-s). Then the comparison
      above erroneously makes new mount shared and sets its mnt_master to
      last_source->mnt_master. The patch fixes the problem by handling zero
      mnt_group_id-s as though they are unequal.
      
      The similar problem exists in the implementation of "else" clause above
      when we have to ascend upward in the master/slave tree by calling:
      
      >    last_source = last_source->mnt_master;
      >    last_dest = last_source->mnt_parent;
      
      proper number of times. The last step is governed by
      "n->mnt_group_id != last_dest->mnt_group_id" condition that may lie if
      both are zero. The patch fixes this case in the same way as the former one.
      
      [AV: don't open-code an obvious helper...]
      Signed-off-by: default avatarMaxim Patlasov <mpatlasov@virtuozzo.com>
      Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      50d0aee1
    • Wang YanQing's avatar
      x86/sysfb_efi: Fix valid BAR address range check · 1dc34f46
      Wang YanQing authored
      commit c10fcb14 upstream.
      
      The code for checking whether a BAR address range is valid will break
      out of the loop when a start address of 0x0 is encountered.
      
      This behaviour is wrong since by breaking out of the loop we may miss
      the BAR that describes the EFI frame buffer in a later iteration.
      
      Because of this bug I can't use video=efifb: boot parameter to get
      efifb on my new ThinkPad E550 for my old linux system hard disk with
      3.10 kernel. In 3.10, efifb is the only choice due to DRM/I915 not
      supporting the GPU.
      
      This patch also add a trivial optimization to break out after we find
      the frame buffer address range without testing later BARs.
      Signed-off-by: default avatarWang YanQing <udknight@gmail.com>
      [ Rewrote changelog. ]
      Signed-off-by: default avatarMatt Fleming <matt@codeblueprint.co.uk>
      Reviewed-by: default avatarPeter Jones <pjones@redhat.com>
      Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
      Cc: David Herrmann <dh.herrmann@gmail.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
      Cc: linux-efi@vger.kernel.org
      Link: http://lkml.kernel.org/r/1462454061-21561-2-git-send-email-matt@codeblueprint.co.ukSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      1dc34f46
    • Prarit Bhargava's avatar
      ACPICA: Dispatcher: Update thread ID for recursive method calls · a89fedb3
      Prarit Bhargava authored
      commit 93d68841 upstream.
      
      ACPICA commit 7a3bd2d962f221809f25ddb826c9e551b916eb25
      
      Set the mutex owner thread ID.
      Original patch from: Prarit Bhargava <prarit@redhat.com>
      
      Link: https://bugzilla.kernel.org/show_bug.cgi?id=115121
      Link: https://github.com/acpica/acpica/commit/7a3bd2d9Signed-off-by: default avatarPrarit Bhargava <prarit@redhat.com>
      Tested-by: Andy Lutomirski <luto@kernel.org> # On a Dell XPS 13 9350
      Signed-off-by: default avatarBob Moore <robert.moore@intel.com>
      Signed-off-by: default avatarLv Zheng <lv.zheng@intel.com>
      Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      a89fedb3
    • Matt Fleming's avatar
      MAINTAINERS: Remove asterisk from EFI directory names · c7e79079
      Matt Fleming authored
      commit e8dfe6d8 upstream.
      
      Mark reported that having asterisks on the end of directory names
      confuses get_maintainer.pl when it encounters subdirectories, and that
      my name does not appear when run on drivers/firmware/efi/libstub.
      Reported-by: default avatarMark Rutland <mark.rutland@arm.com>
      Signed-off-by: default avatarMatt Fleming <matt@codeblueprint.co.uk>
      Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: linux-efi@vger.kernel.org
      Link: http://lkml.kernel.org/r/1462303781-8686-2-git-send-email-matt@codeblueprint.co.ukSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      c7e79079
    • Alex Deucher's avatar
      drm/radeon: make sure vertical front porch is at least 1 · fae66a38
      Alex Deucher authored
      commit 3104b812 upstream.
      
      hw doesn't like a 0 value.
      Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      fae66a38
    • Chunyu Hu's avatar
      tracing: Don't display trigger file for events that can't be enabled · c6f0144b
      Chunyu Hu authored
      commit 854145e0 upstream.
      
      Currently register functions for events will be called
      through the 'reg' field of event class directly without
      any check when seting up triggers.
      
      Triggers for events that don't support register through
      debug fs (events under events/ftrace are for trace-cmd to
      read event format, and most of them don't have a register
      function except events/ftrace/functionx) can't be enabled
      at all, and an oops will be hit when setting up trigger
      for those events, so just not creating them is an easy way
      to avoid the oops.
      
      Link: http://lkml.kernel.org/r/1462275274-3911-1-git-send-email-chuhu@redhat.com
      
      Fixes: 85f2b082 ("tracing: Add basic event trigger framework")
      Signed-off-by: default avatarChunyu Hu <chuhu@redhat.com>
      Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      c6f0144b
    • Linus Torvalds's avatar
      Minimal fix-up of bad hashing behavior of hash_64() · a05ede07
      Linus Torvalds authored
      commit 689de1d6 upstream.
      
      This is a fairly minimal fixup to the horribly bad behavior of hash_64()
      with certain input patterns.
      
      In particular, because the multiplicative value used for the 64-bit hash
      was intentionally bit-sparse (so that the multiply could be done with
      shifts and adds on architectures without hardware multipliers), some
      bits did not get spread out very much.  In particular, certain fairly
      common bit ranges in the input (roughly bits 12-20: commonly with the
      most information in them when you hash things like byte offsets in files
      or memory that have block factors that mean that the low bits are often
      zero) would not necessarily show up much in the result.
      
      There's a bigger patch-series brewing to fix up things more completely,
      but this is the fairly minimal fix for the 64-bit hashing problem.  It
      simply picks a much better constant multiplier, spreading the bits out a
      lot better.
      
      NOTE! For 32-bit architectures, the bad old hash_64() remains the same
      for now, since 64-bit multiplies are expensive.  The bigger hashing
      cleanup will replace the 32-bit case with something better.
      
      The new constants were picked by George Spelvin who wrote that bigger
      cleanup series.  I just picked out the constants and part of the comment
      from that series.
      
      Cc: George Spelvin <linux@horizon.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      a05ede07
    • Anton Blanchard's avatar
      powerpc: Fix bad inline asm constraint in create_zero_mask() · b0fbdaf0
      Anton Blanchard authored
      commit b4c11211 upstream.
      
      In create_zero_mask() we have:
      
      	addi	%1,%2,-1
      	andc	%1,%1,%2
      	popcntd	%0,%1
      
      using the "r" constraint for %2. r0 is a valid register in the "r" set,
      but addi X,r0,X turns it into an li:
      
      	li	r7,-1
      	andc	r7,r7,r0
      	popcntd	r4,r7
      
      Fix this by using the "b" constraint, for which r0 is not a valid
      register.
      
      This was found with a kernel build using gcc trunk, narrowed down to
      when -frename-registers was enabled at -O2. It is just luck however
      that we aren't seeing this on older toolchains.
      
      Thanks to Segher for working with me to find this issue.
      
      Fixes: d0cebfa6 ("powerpc: word-at-a-time optimization for 64-bit Little Endian")
      Signed-off-by: default avatarAnton Blanchard <anton@samba.org>
      Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      b0fbdaf0
    • Tony Luck's avatar
      EDAC: i7core, sb_edac: Don't return NOTIFY_BAD from mce_decoder callback · a4354c6c
      Tony Luck authored
      commit c4fc1956 upstream.
      
      Both of these drivers can return NOTIFY_BAD, but this terminates
      processing other callbacks that were registered later on the chain.
      Since the driver did nothing to log the error it seems wrong to prevent
      other interested parties from seeing it. E.g. neither of them had even
      bothered to check the type of the error to see if it was a memory error
      before the return NOTIFY_BAD.
      Signed-off-by: default avatarTony Luck <tony.luck@intel.com>
      Acked-by: default avatarAristeu Rozanski <aris@redhat.com>
      Acked-by: default avatarMauro Carvalho Chehab <mchehab@osg.samsung.com>
      Cc: linux-edac <linux-edac@vger.kernel.org>
      Link: http://lkml.kernel.org/r/72937355dd92318d2630979666063f8a2853495b.1461864507.git.tony.luck@intel.comSigned-off-by: default avatarBorislav Petkov <bp@suse.de>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      a4354c6c
    • Minchan Kim's avatar
      mm: vmscan: reclaim highmem zone if buffer_heads is over limit · 2f3700fb
      Minchan Kim authored
      commit 7bf52fb8 upstream.
      
      We have been reclaimed highmem zone if buffer_heads is over limit but
      commit 6b4f7799 ("mm: vmscan: invoke slab shrinkers from
      shrink_zone()") changed the behavior so it doesn't reclaim highmem zone
      although buffer_heads is over the limit.  This patch restores the logic.
      
      Fixes: 6b4f7799 ("mm: vmscan: invoke slab shrinkers from shrink_zone()")
      Signed-off-by: default avatarMinchan Kim <minchan@kernel.org>
      Cc: Johannes Weiner <hannes@cmpxchg.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 avatarKamal Mostafa <kamal@canonical.com>
      2f3700fb
    • Konstantin Khlebnikov's avatar
      mm/huge_memory: replace VM_NO_THP VM_BUG_ON with actual VMA check · a1b05bef
      Konstantin Khlebnikov authored
      commit 3486b85a upstream.
      
      Khugepaged detects own VMAs by checking vm_file and vm_ops but this way
      it cannot distinguish private /dev/zero mappings from other special
      mappings like /dev/hpet which has no vm_ops and popultes PTEs in mmap.
      
      This fixes false-positive VM_BUG_ON and prevents installing THP where
      they are not expected.
      
      Link: http://lkml.kernel.org/r/CACT4Y+ZmuZMV5CjSFOeXviwQdABAgT7T+StKfTqan9YDtgEi5g@mail.gmail.com
      Fixes: 78f11a25 ("mm: thp: fix /dev/zero MAP_PRIVATE and vm_flags cleanups")
      Signed-off-by: default avatarKonstantin Khlebnikov <koct9i@gmail.com>
      Reported-by: default avatarDmitry Vyukov <dvyukov@google.com>
      Acked-by: default avatarVlastimil Babka <vbabka@suse.cz>
      Acked-by: default avatarKirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Cc: Dmitry Vyukov <dvyukov@google.com>
      Cc: Andrea Arcangeli <aarcange@redhat.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      a1b05bef
    • Jason Gunthorpe's avatar
      IB/security: Restrict use of the write() interface · 35c8a0ed
      Jason Gunthorpe authored
      commit e6bd18f5 upstream.
      
      The drivers/infiniband stack uses write() as a replacement for
      bi-directional ioctl().  This is not safe. There are ways to
      trigger write calls that result in the return structure that
      is normally written to user space being shunted off to user
      specified kernel memory instead.
      
      For the immediate repair, detect and deny suspicious accesses to
      the write API.
      
      For long term, update the user space libraries and the kernel API
      to something that doesn't present the same security vulnerabilities
      (likely a structured ioctl() interface).
      
      The impacted uAPI interfaces are generally only available if
      hardware from drivers/infiniband is installed in the system.
      Reported-by: default avatarJann Horn <jann@thejh.net>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarJason Gunthorpe <jgunthorpe@obsidianresearch.com>
      [ Expanded check to all known write() entry points ]
      Signed-off-by: default avatarDoug Ledford <dledford@redhat.com>
      [ kamal: backport to 4.2-stable: no staging/rdma/ ]
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      35c8a0ed
    • Sascha Hauer's avatar
      ARM: SoCFPGA: Fix secondary CPU startup in thumb2 kernel · 8a3a98ee
      Sascha Hauer authored
      commit 5616f367 upstream.
      
      The secondary CPU starts up in ARM mode. When the kernel is compiled in
      thumb2 mode we have to explicitly compile the secondary startup
      trampoline in ARM mode, otherwise the CPU will go to Nirvana.
      Signed-off-by: default avatarSascha Hauer <s.hauer@pengutronix.de>
      Reported-by: default avatarSteffen Trumtrar <s.trumtrar@pengutronix.de>
      Suggested-by: default avatarArd Biesheuvel <ard.biesheuvel@linaro.org>
      Signed-off-by: default avatarDinh Nguyen <dinguyen@opensource.altera.com>
      Signed-off-by: default avatarKevin Hilman <khilman@baylibre.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      8a3a98ee
    • Imre Deak's avatar
      drm/i915/ddi: Fix eDP VDD handling during booting and suspend/resume · ddae7dd6
      Imre Deak authored
      commit 5eaa60c7 upstream.
      
      The driver's VDD on/off logic assumes that whenever the VDD is on we
      also hold an AUX power domain reference. Since BIOS can leave the VDD on
      during booting and resuming and on DDI platforms we won't take a
      corresponding power reference, the above assumption won't hold on those
      platforms and an eventual delayed VDD off work will do an extraneous AUX
      power domain put resulting in a refcount underflow. Fix this the same
      way we did this for non-DDI DP encoders:
      
      commit 6d93c0c4 ("drm/i915: fix VDD state tracking after system
      resume")
      
      At the same time call the DP encoder suspend handler the same way as the
      non-DDI DP encoders do to flush any pending VDD off work. Leaving the
      work running may cause a HW access where we don't expect this (at a point
      where power domains are suspended already).
      
      While at it remove an unnecessary function call indirection.
      
      This fixed for me AUX refcount underflow problems on BXT during
      suspend/resume.
      
      CC: Ville Syrjälä <ville.syrjala@linux.intel.com>
      Signed-off-by: default avatarImre Deak <imre.deak@intel.com>
      Reviewed-by: default avatarVille Syrjälä <ville.syrjala@linux.intel.com>
      Link: http://patchwork.freedesktop.org/patch/msgid/1460963062-13211-4-git-send-email-imre.deak@intel.com
      (cherry picked from commit bf93ba67)
      Signed-off-by: default avatarJani Nikula <jani.nikula@intel.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      ddae7dd6
    • Imre Deak's avatar
      drm/i915: Fix system resume if PCI device remained enabled · 307d9ea5
      Imre Deak authored
      commit dab9a266 upstream.
      
      During system resume we depended on pci_enable_device() also putting the
      device into PCI D0 state. This won't work if the PCI device was already
      enabled but still in D3 state. This is because pci_enable_device() is
      refcounted and will not change the HW state if called with a non-zero
      refcount. Leaving the device in D3 will make all subsequent device
      accesses fail.
      
      This didn't cause a problem most of the time, since we resumed with an
      enable refcount of 0. But it fails at least after module reload because
      after that we also happen to leak a PCI device enable reference: During
      probing we call drm_get_pci_dev() which will enable the PCI device, but
      during device removal drm_put_dev() won't disable it. This is a bug of
      its own in DRM core, but without much harm as it only leaves the PCI
      device enabled. Fixing it is also a bit more involved, due to DRM
      mid-layering and because it affects non-i915 drivers too. The fix in
      this patch is valid regardless of the problem in DRM core.
      
      v2:
      - Add a code comment about the relation of this fix to the freeze/thaw
        vs. the suspend/resume phases. (Ville)
      - Add a code comment about the inconsistent ordering of set power state
        and device enable calls. (Chris)
      
      CC: Ville Syrjälä <ville.syrjala@linux.intel.com>
      CC: Chris Wilson <chris@chris-wilson.co.uk>
      Signed-off-by: default avatarImre Deak <imre.deak@intel.com>
      Reviewed-by: default avatarVille Syrjälä <ville.syrjala@linux.intel.com>
      Link: http://patchwork.freedesktop.org/patch/msgid/1460979954-14503-1-git-send-email-imre.deak@intel.com
      (cherry picked from commit 44410cd0)
      Signed-off-by: default avatarJani Nikula <jani.nikula@intel.com>
      [ kamal: backport to 4.2-stable ]
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      307d9ea5
    • Michael Neuling's avatar
      cxl: Keep IRQ mappings on context teardown · 8495d7c9
      Michael Neuling authored
      commit d6776bba upstream.
      
      Keep IRQ mappings on context teardown.  This won't leak IRQs as if we
      allocate the mapping again, the generic code will give the same
      mapping used last time.
      
      Doing this works around a race in the generic code. Masking the
      interrupt introduces a race which can crash the kernel or result in
      IRQ that is never EOIed. The lost of EOI results in all subsequent
      mappings to the same HW IRQ never receiving an interrupt.
      
      We've seen this race with cxl test cases which are doing heavy context
      startup and teardown at the same time as heavy interrupt load.
      
      A fix to the generic code is being investigated also.
      Signed-off-by: default avatarMichael Neuling <mikey@neuling.org>
      Tested-by: default avatarAndrew Donnellan <andrew.donnellan@au1.ibm.com>
      Acked-by: default avatarIan Munsie <imunsie@au1.ibm.com>
      Tested-by: default avatarVaibhav Jain <vaibhav@linux.vnet.ibm.com>
      Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      8495d7c9
    • cpaul@redhat.com's avatar
      drm/dp/mst: Get validated port ref in drm_dp_update_payload_part1() · 1fbb922a
      cpaul@redhat.com authored
      commit 263efde3 upstream.
      
      We can thank KASAN for finding this, otherwise I probably would have spent
      hours on it. This fixes a somewhat harder to trigger kernel panic, occuring
      while enabling MST where the port we were currently updating the payload on
      would have all of it's refs dropped before we finished what we were doing:
      
      ==================================================================
      BUG: KASAN: use-after-free in drm_dp_update_payload_part1+0xb3f/0xdb0 [drm_kms_helper] at addr ffff8800d29de018
      Read of size 4 by task Xorg/973
      =============================================================================
      BUG kmalloc-2048 (Tainted: G    B   W      ): kasan: bad access detected
      -----------------------------------------------------------------------------
      
      INFO: Allocated in drm_dp_add_port+0x1aa/0x1ed0 [drm_kms_helper] age=16477 cpu=0 pid=2175
      	___slab_alloc+0x472/0x490
      	__slab_alloc+0x20/0x40
      	kmem_cache_alloc_trace+0x151/0x190
      	drm_dp_add_port+0x1aa/0x1ed0 [drm_kms_helper]
      	drm_dp_send_link_address+0x526/0x960 [drm_kms_helper]
      	drm_dp_check_and_send_link_address+0x1ac/0x210 [drm_kms_helper]
      	drm_dp_mst_link_probe_work+0x77/0xd0 [drm_kms_helper]
      	process_one_work+0x562/0x1350
      	worker_thread+0xd9/0x1390
      	kthread+0x1c5/0x260
      	ret_from_fork+0x22/0x40
      INFO: Freed in drm_dp_free_mst_port+0x50/0x60 [drm_kms_helper] age=7521 cpu=0 pid=2175
      	__slab_free+0x17f/0x2d0
      	kfree+0x169/0x180
      	drm_dp_free_mst_port+0x50/0x60 [drm_kms_helper]
      	drm_dp_destroy_connector_work+0x2b8/0x490 [drm_kms_helper]
      	process_one_work+0x562/0x1350
      	worker_thread+0xd9/0x1390
      	kthread+0x1c5/0x260
      	ret_from_fork+0x22/0x40
      
      which on this T460s, would eventually lead to kernel panics in somewhat
      random places later in intel_mst_enable_dp() if we got lucky enough.
      Signed-off-by: default avatarLyude <cpaul@redhat.com>
      Signed-off-by: default avatarDave Airlie <airlied@redhat.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      1fbb922a
    • Roman Pen's avatar
      workqueue: fix ghost PENDING flag while doing MQ IO · 8a9e2c02
      Roman Pen authored
      commit 346c09f8 upstream.
      
      The bug in a workqueue leads to a stalled IO request in MQ ctx->rq_list
      with the following backtrace:
      
      [  601.347452] INFO: task kworker/u129:5:1636 blocked for more than 120 seconds.
      [  601.347574]       Tainted: G           O    4.4.5-1-storage+ #6
      [  601.347651] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
      [  601.348142] kworker/u129:5  D ffff880803077988     0  1636      2 0x00000000
      [  601.348519] Workqueue: ibnbd_server_fileio_wq ibnbd_dev_file_submit_io_worker [ibnbd_server]
      [  601.348999]  ffff880803077988 ffff88080466b900 ffff8808033f9c80 ffff880803078000
      [  601.349662]  ffff880807c95000 7fffffffffffffff ffffffff815b0920 ffff880803077ad0
      [  601.350333]  ffff8808030779a0 ffffffff815b01d5 0000000000000000 ffff880803077a38
      [  601.350965] Call Trace:
      [  601.351203]  [<ffffffff815b0920>] ? bit_wait+0x60/0x60
      [  601.351444]  [<ffffffff815b01d5>] schedule+0x35/0x80
      [  601.351709]  [<ffffffff815b2dd2>] schedule_timeout+0x192/0x230
      [  601.351958]  [<ffffffff812d43f7>] ? blk_flush_plug_list+0xc7/0x220
      [  601.352208]  [<ffffffff810bd737>] ? ktime_get+0x37/0xa0
      [  601.352446]  [<ffffffff815b0920>] ? bit_wait+0x60/0x60
      [  601.352688]  [<ffffffff815af784>] io_schedule_timeout+0xa4/0x110
      [  601.352951]  [<ffffffff815b3a4e>] ? _raw_spin_unlock_irqrestore+0xe/0x10
      [  601.353196]  [<ffffffff815b093b>] bit_wait_io+0x1b/0x70
      [  601.353440]  [<ffffffff815b056d>] __wait_on_bit+0x5d/0x90
      [  601.353689]  [<ffffffff81127bd0>] wait_on_page_bit+0xc0/0xd0
      [  601.353958]  [<ffffffff81096db0>] ? autoremove_wake_function+0x40/0x40
      [  601.354200]  [<ffffffff81127cc4>] __filemap_fdatawait_range+0xe4/0x140
      [  601.354441]  [<ffffffff81127d34>] filemap_fdatawait_range+0x14/0x30
      [  601.354688]  [<ffffffff81129a9f>] filemap_write_and_wait_range+0x3f/0x70
      [  601.354932]  [<ffffffff811ced3b>] blkdev_fsync+0x1b/0x50
      [  601.355193]  [<ffffffff811c82d9>] vfs_fsync_range+0x49/0xa0
      [  601.355432]  [<ffffffff811cf45a>] blkdev_write_iter+0xca/0x100
      [  601.355679]  [<ffffffff81197b1a>] __vfs_write+0xaa/0xe0
      [  601.355925]  [<ffffffff81198379>] vfs_write+0xa9/0x1a0
      [  601.356164]  [<ffffffff811c59d8>] kernel_write+0x38/0x50
      
      The underlying device is a null_blk, with default parameters:
      
        queue_mode    = MQ
        submit_queues = 1
      
      Verification that nullb0 has something inflight:
      
      root@pserver8:~# cat /sys/block/nullb0/inflight
             0        1
      root@pserver8:~# find /sys/block/nullb0/mq/0/cpu* -name rq_list -print -exec cat {} \;
      ...
      /sys/block/nullb0/mq/0/cpu2/rq_list
      CTX pending:
              ffff8838038e2400
      ...
      
      During debug it became clear that stalled request is always inserted in
      the rq_list from the following path:
      
         save_stack_trace_tsk + 34
         blk_mq_insert_requests + 231
         blk_mq_flush_plug_list + 281
         blk_flush_plug_list + 199
         wait_on_page_bit + 192
         __filemap_fdatawait_range + 228
         filemap_fdatawait_range + 20
         filemap_write_and_wait_range + 63
         blkdev_fsync + 27
         vfs_fsync_range + 73
         blkdev_write_iter + 202
         __vfs_write + 170
         vfs_write + 169
         kernel_write + 56
      
      So blk_flush_plug_list() was called with from_schedule == true.
      
      If from_schedule is true, that means that finally blk_mq_insert_requests()
      offloads execution of __blk_mq_run_hw_queue() and uses kblockd workqueue,
      i.e. it calls kblockd_schedule_delayed_work_on().
      
      That means, that we race with another CPU, which is about to execute
      __blk_mq_run_hw_queue() work.
      
      Further debugging shows the following traces from different CPUs:
      
        CPU#0                                  CPU#1
        ----------------------------------     -------------------------------
        reqeust A inserted
        STORE hctx->ctx_map[0] bit marked
        kblockd_schedule...() returns 1
        <schedule to kblockd workqueue>
                                               request B inserted
                                               STORE hctx->ctx_map[1] bit marked
                                               kblockd_schedule...() returns 0
        *** WORK PENDING bit is cleared ***
        flush_busy_ctxs() is executed, but
        bit 1, set by CPU#1, is not observed
      
      As a result request B pended forever.
      
      This behaviour can be explained by speculative LOAD of hctx->ctx_map on
      CPU#0, which is reordered with clear of PENDING bit and executed _before_
      actual STORE of bit 1 on CPU#1.
      
      The proper fix is an explicit full barrier <mfence>, which guarantees
      that clear of PENDING bit is to be executed before all possible
      speculative LOADS or STORES inside actual work function.
      Signed-off-by: default avatarRoman Pen <roman.penyaev@profitbricks.com>
      Cc: Gioh Kim <gi-oh.kim@profitbricks.com>
      Cc: Michael Wang <yun.wang@profitbricks.com>
      Cc: Tejun Heo <tj@kernel.org>
      Cc: Jens Axboe <axboe@kernel.dk>
      Cc: linux-block@vger.kernel.org
      Cc: linux-kernel@vger.kernel.org
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      8a9e2c02
    • Conrad Kostecki's avatar
      ALSA: hda - Add dock support for ThinkPad X260 · 3e3fd15a
      Conrad Kostecki authored
      commit 037e1197 upstream.
      
      Fixes audio output on a ThinkPad X260, when using Lenovo CES 2013
      docking station series (basic, pro, ultra).
      Signed-off-by: default avatarConrad Kostecki <ck+linuxkernel@bl4ckb0x.de>
      Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      3e3fd15a
    • Jasem Mutlaq's avatar
      USB: serial: cp210x: add Straizona Focusers device ids · 32d7e418
      Jasem Mutlaq authored
      commit 613ac23a upstream.
      
      Adding VID:PID for Straizona Focusers to cp210x driver.
      Signed-off-by: default avatarJasem Mutlaq <mutlaqja@ikarustech.com>
      Signed-off-by: default avatarJohan Hovold <johan@kernel.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      32d7e418
    • Mike Manning's avatar
      USB: serial: cp210x: add ID for Link ECU · 3c01154a
      Mike Manning authored
      commit 1d377f4d upstream.
      
      The Link ECU is an aftermarket ECU computer for vehicles that provides
      full tuning abilities as well as datalogging and displaying capabilities
      via the USB to Serial adapter built into the device.
      Signed-off-by: default avatarMike Manning <michael@bsch.com.au>
      Signed-off-by: default avatarJohan Hovold <johan@kernel.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      3c01154a
    • Laszlo Ersek's avatar
      efi: Fix out-of-bounds read in variable_matches() · 479f2297
      Laszlo Ersek authored
      commit 630ba0cc upstream.
      
      The variable_matches() function can currently read "var_name[len]", for
      example when:
      
       - var_name[0] == 'a',
       - len == 1
       - match_name points to the NUL-terminated string "ab".
      
      This function is supposed to accept "var_name" inputs that are not
      NUL-terminated (hence the "len" parameter"). Document the function, and
      access "var_name[*match]" only if "*match" is smaller than "len".
      Reported-by: default avatarChris Wilson <chris@chris-wilson.co.uk>
      Signed-off-by: default avatarLaszlo Ersek <lersek@redhat.com>
      Cc: Peter Jones <pjones@redhat.com>
      Cc: Matthew Garrett <mjg59@coreos.com>
      Cc: Jason Andryuk <jandryuk@gmail.com>
      Cc: Jani Nikula <jani.nikula@linux.intel.com>
      Link: http://thread.gmane.org/gmane.comp.freedesktop.xorg.drivers.intel/86906Signed-off-by: default avatarMatt Fleming <matt@codeblueprint.co.uk>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      479f2297
    • Javier Martinez Canillas's avatar
      i2c: exynos5: Fix possible ABBA deadlock by keeping I2C clock prepared · f9c43153
      Javier Martinez Canillas authored
      commit 10ff4c52 upstream.
      
      The exynos5 I2C controller driver always prepares and enables a clock
      before using it and then disables unprepares it when the clock is not
      used anymore.
      
      But this can cause a possible ABBA deadlock in some scenarios since a
      driver that uses regmap to access its I2C registers, will first grab
      the regmap lock and then the I2C xfer function will grab the prepare
      lock when preparing the I2C clock. But since the clock driver also
      uses regmap for I2C accesses, preparing a clock will first grab the
      prepare lock and then the regmap lock when using the regmap API.
      
      An example of this happens on the Exynos5422 Odroid XU4 board where a
      s2mps11 PMIC is used and both the s2mps11 regulators and clk drivers
      share the same I2C regmap.
      
      The possible deadlock is reported by the kernel lockdep:
      
        Possible unsafe locking scenario:
      
              CPU0                    CPU1
              ----                    ----
         lock(sec_core:428:(regmap)->lock);
                                      lock(prepare_lock);
                                      lock(sec_core:428:(regmap)->lock);
         lock(prepare_lock);
      
        *** DEADLOCK ***
      
      Fix it by leaving the code prepared on probe and use {en,dis}able in
      the I2C transfer function.
      
      This patch is similar to commit 34e81ad5 ("i2c: s3c2410: fix ABBA
      deadlock by keeping clock prepared") that fixes the same bug in other
      driver for an I2C controller found in Samsung SoCs.
      Reported-by: default avatarAnand Moon <linux.amoon@gmail.com>
      Signed-off-by: default avatarJavier Martinez Canillas <javier@osg.samsung.com>
      Reviewed-by: default avatarAnand Moon <linux.amoon@gmail.com>
      Reviewed-by: default avatarKrzysztof Kozlowski <k.kozlowski@samsung.com>
      Signed-off-by: default avatarWolfram Sang <wsa@the-dreams.de>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      f9c43153
    • Michael Ellerman's avatar
      i2c: cpm: Fix build break due to incompatible pointer types · ae6fb4ae
      Michael Ellerman authored
      commit 609d5a1b upstream.
      
      Since commit ea8daa7b ("kbuild: Add option to turn incompatible
      pointer check into error"), assignments from an incompatible pointer
      types have become a hard error, eg:
      
        drivers/i2c/busses/i2c-cpm.c:545:91: error: passing argument 3 of
        'dma_alloc_coherent' from incompatible pointer type
      
      Fix the build break by converting txdma & rxdma to dma_addr_t.
      Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
      Signed-off-by: default avatarWolfram Sang <wsa@the-dreams.de>
      Fixes: ea8daa7bSigned-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      ae6fb4ae
    • Krzysztof Kozlowski's avatar
      iio: ak8975: Fix NULL pointer exception on early interrupt · b75c95f1
      Krzysztof Kozlowski authored
      commit 07d2390e upstream.
      
      In certain probe conditions the interrupt came right after registering
      the handler causing a NULL pointer exception because of uninitialized
      waitqueue:
      
      $ udevadm trigger
      i2c-gpio i2c-gpio-1: using pins 143 (SDA) and 144 (SCL)
      i2c-gpio i2c-gpio-3: using pins 53 (SDA) and 52 (SCL)
      Unable to handle kernel NULL pointer dereference at virtual address 00000000
      pgd = e8b38000
      [00000000] *pgd=00000000
      Internal error: Oops: 5 [#1] SMP ARM
      Modules linked in: snd_soc_i2s(+) i2c_gpio(+) snd_soc_idma snd_soc_s3c_dma snd_soc_core snd_pcm_dmaengine snd_pcm snd_timer snd soundcore ac97_bus spi_s3c64xx pwm_samsung dwc2 exynos_adc phy_exynos_usb2 exynosdrm exynos_rng rng_core rtc_s3c
      CPU: 0 PID: 717 Comm: data-provider-m Not tainted 4.6.0-rc1-next-20160401-00011-g1b8d87473b9e-dirty #101
      Hardware name: SAMSUNG EXYNOS (Flattened Device Tree)
      (...)
      (__wake_up_common) from [<c0379624>] (__wake_up+0x38/0x4c)
      (__wake_up) from [<c0a41d30>] (ak8975_irq_handler+0x28/0x30)
      (ak8975_irq_handler) from [<c0386720>] (handle_irq_event_percpu+0x88/0x140)
      (handle_irq_event_percpu) from [<c038681c>] (handle_irq_event+0x44/0x68)
      (handle_irq_event) from [<c0389c40>] (handle_edge_irq+0xf0/0x19c)
      (handle_edge_irq) from [<c0385e04>] (generic_handle_irq+0x24/0x34)
      (generic_handle_irq) from [<c05ee360>] (exynos_eint_gpio_irq+0x50/0x68)
      (exynos_eint_gpio_irq) from [<c0386720>] (handle_irq_event_percpu+0x88/0x140)
      (handle_irq_event_percpu) from [<c038681c>] (handle_irq_event+0x44/0x68)
      (handle_irq_event) from [<c0389a70>] (handle_fasteoi_irq+0xb4/0x194)
      (handle_fasteoi_irq) from [<c0385e04>] (generic_handle_irq+0x24/0x34)
      (generic_handle_irq) from [<c03860b4>] (__handle_domain_irq+0x5c/0xb4)
      (__handle_domain_irq) from [<c0301774>] (gic_handle_irq+0x54/0x94)
      (gic_handle_irq) from [<c030c910>] (__irq_usr+0x50/0x80)
      
      The bug was reproduced on exynos4412-trats2 (with a max77693 device also
      using i2c-gpio) after building max77693 as a module.
      
      Fixes: 94a6d5cf ("iio:ak8975 Implement data ready interrupt handling")
      Signed-off-by: default avatarKrzysztof Kozlowski <k.kozlowski@samsung.com>
      Tested-by: default avatarGregor Boirie <gregor.boirie@parrot.com>
      Signed-off-by: default avatarJonathan Cameron <jic23@kernel.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      b75c95f1
    • Mark Brown's avatar
      ASoC: dapm: Make sure we have a card when displaying component widgets · afc0d6b1
      Mark Brown authored
      commit 47325078 upstream.
      
      The dummy component is reused for all cards so we special case and don't
      bind it to any of them.  This means that code like that displaying the
      component widgets that tries to look at the card will crash.  In the
      future we will fix this by ensuring that the dummy component looks like
      other components but that is invasive and so not suitable for a fix.
      Instead add a special case check here.
      Reported-by: default avatarHarry Pan <harry.pan@intel.com>
      Suggested-by: default avatarLars-Peter Clausen <lars@metafoo.de>
      Signed-off-by: default avatarMark Brown <broonie@kernel.org>
      [ kamal: backport to 4.2-stable ]
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      afc0d6b1
    • Sugar Zhang's avatar
      ASoC: rt5640: Correct the digital interface data select · 903262ae
      Sugar Zhang authored
      commit 653aa464 upstream.
      
      this patch corrects the interface adc/dac control register definition
      according to datasheet.
      Signed-off-by: default avatarSugar Zhang <sugar.zhang@rock-chips.com>
      Signed-off-by: default avatarMark Brown <broonie@kernel.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      903262ae
  2. 04 May, 2016 9 commits
    • Hector Marco-Gisbert's avatar
      x86/mm/32: Enable full randomization on i386 and X86_32 · 5c66bd4b
      Hector Marco-Gisbert authored
      commit 8b8addf8 upstream.
      
      Currently on i386 and on X86_64 when emulating X86_32 in legacy mode, only
      the stack and the executable are randomized but not other mmapped files
      (libraries, vDSO, etc.). This patch enables randomization for the
      libraries, vDSO and mmap requests on i386 and in X86_32 in legacy mode.
      
      By default on i386 there are 8 bits for the randomization of the libraries,
      vDSO and mmaps which only uses 1MB of VA.
      
      This patch preserves the original randomness, using 1MB of VA out of 3GB or
      4GB. We think that 1MB out of 3GB is not a big cost for having the ASLR.
      
      The first obvious security benefit is that all objects are randomized (not
      only the stack and the executable) in legacy mode which highly increases
      the ASLR effectiveness, otherwise the attackers may use these
      non-randomized areas. But also sensitive setuid/setgid applications are
      more secure because currently, attackers can disable the randomization of
      these applications by setting the ulimit stack to "unlimited". This is a
      very old and widely known trick to disable the ASLR in i386 which has been
      allowed for too long.
      
      Another trick used to disable the ASLR was to set the ADDR_NO_RANDOMIZE
      personality flag, but fortunately this doesn't work on setuid/setgid
      applications because there is security checks which clear Security-relevant
      flags.
      
      This patch always randomizes the mmap_legacy_base address, removing the
      possibility to disable the ASLR by setting the stack to "unlimited".
      Signed-off-by: default avatarHector Marco-Gisbert <hecmargi@upv.es>
      Acked-by: default avatarIsmael Ripoll Ripoll <iripoll@upv.es>
      Acked-by: default avatarKees Cook <keescook@chromium.org>
      Acked-by: default avatarArjan van de Ven <arjan@linux.intel.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: akpm@linux-foundation.org
      Cc: kees Cook <keescook@chromium.org>
      Link: http://lkml.kernel.org/r/1457639460-5242-1-git-send-email-hecmargi@upv.esSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
      Reference: CVE-2016-3672
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      5c66bd4b
    • Kees Cook's avatar
      mm: fold arch_randomize_brk into ARCH_HAS_ELF_RANDOMIZE · 350e988f
      Kees Cook authored
      commit 204db6ed upstream.
      
      The arch_randomize_brk() function is used on several architectures,
      even those that don't support ET_DYN ASLR. To avoid bulky extern/#define
      tricks, consolidate the support under CONFIG_ARCH_HAS_ELF_RANDOMIZE for
      the architectures that support it, while still handling CONFIG_COMPAT_BRK.
      Signed-off-by: default avatarKees Cook <keescook@chromium.org>
      Cc: Hector Marco-Gisbert <hecmargi@upv.es>
      Cc: Russell King <linux@arm.linux.org.uk>
      Reviewed-by: default avatarIngo Molnar <mingo@kernel.org>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Will Deacon <will.deacon@arm.com>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: Alexander Viro <viro@zeniv.linux.org.uk>
      Cc: Oleg Nesterov <oleg@redhat.com>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: "David A. Long" <dave.long@linaro.org>
      Cc: Andrey Ryabinin <a.ryabinin@samsung.com>
      Cc: Arun Chandran <achandran@mvista.com>
      Cc: Yann Droneaud <ydroneaud@opteya.com>
      Cc: Min-Hua Chen <orca.chen@gmail.com>
      Cc: Paul Burton <paul.burton@imgtec.com>
      Cc: Alex Smith <alex@alex-smith.me.uk>
      Cc: Markos Chandras <markos.chandras@imgtec.com>
      Cc: Vineeth Vijayan <vvijayan@mvista.com>
      Cc: Jeff Bailey <jeffbailey@google.com>
      Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com>
      Cc: Ben Hutchings <ben@decadent.org.uk>
      Cc: Behan Webster <behanw@converseincode.com>
      Cc: Ismael Ripoll <iripoll@upv.es>
      Cc: Jan-Simon Mller <dl9pf@gmx.de>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      350e988f
    • Kees Cook's avatar
      mm: split ET_DYN ASLR from mmap ASLR · e19d0939
      Kees Cook authored
      commit d1fd836d upstream.
      
      This fixes the "offset2lib" weakness in ASLR for arm, arm64, mips,
      powerpc, and x86.  The problem is that if there is a leak of ASLR from
      the executable (ET_DYN), it means a leak of shared library offset as
      well (mmap), and vice versa.  Further details and a PoC of this attack
      is available here:
      
        http://cybersecurity.upv.es/attacks/offset2lib/offset2lib.html
      
      With this patch, a PIE linked executable (ET_DYN) has its own ASLR
      region:
      
        $ ./show_mmaps_pie
        54859ccd6000-54859ccd7000 r-xp  ...  /tmp/show_mmaps_pie
        54859ced6000-54859ced7000 r--p  ...  /tmp/show_mmaps_pie
        54859ced7000-54859ced8000 rw-p  ...  /tmp/show_mmaps_pie
        7f75be764000-7f75be91f000 r-xp  ...  /lib/x86_64-linux-gnu/libc.so.6
        7f75be91f000-7f75beb1f000 ---p  ...  /lib/x86_64-linux-gnu/libc.so.6
        7f75beb1f000-7f75beb23000 r--p  ...  /lib/x86_64-linux-gnu/libc.so.6
        7f75beb23000-7f75beb25000 rw-p  ...  /lib/x86_64-linux-gnu/libc.so.6
        7f75beb25000-7f75beb2a000 rw-p  ...
        7f75beb2a000-7f75beb4d000 r-xp  ...  /lib64/ld-linux-x86-64.so.2
        7f75bed45000-7f75bed46000 rw-p  ...
        7f75bed46000-7f75bed47000 r-xp  ...
        7f75bed47000-7f75bed4c000 rw-p  ...
        7f75bed4c000-7f75bed4d000 r--p  ...  /lib64/ld-linux-x86-64.so.2
        7f75bed4d000-7f75bed4e000 rw-p  ...  /lib64/ld-linux-x86-64.so.2
        7f75bed4e000-7f75bed4f000 rw-p  ...
        7fffb3741000-7fffb3762000 rw-p  ...  [stack]
        7fffb377b000-7fffb377d000 r--p  ...  [vvar]
        7fffb377d000-7fffb377f000 r-xp  ...  [vdso]
      
      The change is to add a call the newly created arch_mmap_rnd() into the
      ELF loader for handling ET_DYN ASLR in a separate region from mmap ASLR,
      as was already done on s390.  Removes CONFIG_BINFMT_ELF_RANDOMIZE_PIE,
      which is no longer needed.
      Signed-off-by: default avatarKees Cook <keescook@chromium.org>
      Reported-by: default avatarHector Marco-Gisbert <hecmargi@upv.es>
      Cc: Russell King <linux@arm.linux.org.uk>
      Reviewed-by: default avatarIngo Molnar <mingo@kernel.org>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Will Deacon <will.deacon@arm.com>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: Alexander Viro <viro@zeniv.linux.org.uk>
      Cc: Oleg Nesterov <oleg@redhat.com>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: "David A. Long" <dave.long@linaro.org>
      Cc: Andrey Ryabinin <a.ryabinin@samsung.com>
      Cc: Arun Chandran <achandran@mvista.com>
      Cc: Yann Droneaud <ydroneaud@opteya.com>
      Cc: Min-Hua Chen <orca.chen@gmail.com>
      Cc: Paul Burton <paul.burton@imgtec.com>
      Cc: Alex Smith <alex@alex-smith.me.uk>
      Cc: Markos Chandras <markos.chandras@imgtec.com>
      Cc: Vineeth Vijayan <vvijayan@mvista.com>
      Cc: Jeff Bailey <jeffbailey@google.com>
      Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com>
      Cc: Ben Hutchings <ben@decadent.org.uk>
      Cc: Behan Webster <behanw@converseincode.com>
      Cc: Ismael Ripoll <iripoll@upv.es>
      Cc: Jan-Simon Mller <dl9pf@gmx.de>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      e19d0939
    • Kees Cook's avatar
      s390: redefine randomize_et_dyn for ELF_ET_DYN_BASE · 2d325291
      Kees Cook authored
      commit c6f5b001 upstream.
      
      In preparation for moving ET_DYN randomization into the ELF loader (which
      requires a static ELF_ET_DYN_BASE), this redefines s390's existing ET_DYN
      randomization in a call to arch_mmap_rnd(). This refactoring results in
      the same ET_DYN randomization on s390.
      Signed-off-by: default avatarKees Cook <keescook@chromium.org>
      Acked-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Reviewed-by: default avatarIngo Molnar <mingo@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 avatarKamal Mostafa <kamal@canonical.com>
      2d325291
    • Kees Cook's avatar
      mm: expose arch_mmap_rnd when available · 97c9ce2a
      Kees Cook authored
      commit 2b68f6ca upstream.
      
      When an architecture fully supports randomizing the ELF load location,
      a per-arch mmap_rnd() function is used to find a randomized mmap base.
      In preparation for randomizing the location of ET_DYN binaries
      separately from mmap, this renames and exports these functions as
      arch_mmap_rnd(). Additionally introduces CONFIG_ARCH_HAS_ELF_RANDOMIZE
      for describing this feature on architectures that support it
      (which is a superset of ARCH_BINFMT_ELF_RANDOMIZE_PIE, since s390
      already supports a separated ET_DYN ASLR from mmap ASLR without the
      ARCH_BINFMT_ELF_RANDOMIZE_PIE logic).
      Signed-off-by: default avatarKees Cook <keescook@chromium.org>
      Cc: Hector Marco-Gisbert <hecmargi@upv.es>
      Cc: Russell King <linux@arm.linux.org.uk>
      Reviewed-by: default avatarIngo Molnar <mingo@kernel.org>
      Cc: Catalin Marinas <catalin.marinas@arm.com>
      Cc: Will Deacon <will.deacon@arm.com>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Cc: Alexander Viro <viro@zeniv.linux.org.uk>
      Cc: Oleg Nesterov <oleg@redhat.com>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: "David A. Long" <dave.long@linaro.org>
      Cc: Andrey Ryabinin <a.ryabinin@samsung.com>
      Cc: Arun Chandran <achandran@mvista.com>
      Cc: Yann Droneaud <ydroneaud@opteya.com>
      Cc: Min-Hua Chen <orca.chen@gmail.com>
      Cc: Paul Burton <paul.burton@imgtec.com>
      Cc: Alex Smith <alex@alex-smith.me.uk>
      Cc: Markos Chandras <markos.chandras@imgtec.com>
      Cc: Vineeth Vijayan <vvijayan@mvista.com>
      Cc: Jeff Bailey <jeffbailey@google.com>
      Cc: Michael Holzheu <holzheu@linux.vnet.ibm.com>
      Cc: Ben Hutchings <ben@decadent.org.uk>
      Cc: Behan Webster <behanw@converseincode.com>
      Cc: Ismael Ripoll <iripoll@upv.es>
      Cc: Jan-Simon Mller <dl9pf@gmx.de>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      97c9ce2a
    • Kees Cook's avatar
      s390: standardize mmap_rnd() usage · 58eb8cee
      Kees Cook authored
      commit 8e89a356 upstream.
      
      In preparation for splitting out ET_DYN ASLR, this refactors the use of
      mmap_rnd() to be used similarly to arm and x86, and extracts the
      checking of PF_RANDOMIZE.
      Signed-off-by: default avatarKees Cook <keescook@chromium.org>
      Acked-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
      Reviewed-by: default avatarIngo Molnar <mingo@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 avatarKamal Mostafa <kamal@canonical.com>
      58eb8cee
    • Martin Schwidefsky's avatar
      s390/mm: align 64-bit PIE binaries to 4GB · 3a86395e
      Martin Schwidefsky authored
      commit 4ba2815d upstream.
      
      The base address (STACK_TOP / 3 * 2) for a 64-bit program is two thirds
      into the 4GB segment at 0x2aa00000000. The randomization added on z13
      can eat another 1GB of the remaining 1.33GB to the next 4GB boundary.
      In the worst case 300MB are left for the executable + bss which may
      cross into the next 4GB segment. This is bad for branch prediction,
      therefore align the base address to 4GB to give the program more room
      before it crosses the 4GB boundary.
      Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      3a86395e
    • Martin Schwidefsky's avatar
      s390: avoid z13 cache aliasing · 7ae77468
      Martin Schwidefsky authored
      commit 1f6b83e5 upstream.
      
      Avoid cache aliasing on z13 by aligning shared objects to multiples
      of 512K. The virtual addresses of a page from a shared file needs
      to have identical bits in the range 2^12 to 2^18.
      Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      7ae77468
    • Kees Cook's avatar
      powerpc: standardize mmap_rnd() usage · e108721a
      Kees Cook authored
      commit ed632274 upstream.
      
      In preparation for splitting out ET_DYN ASLR, this refactors the use of
      mmap_rnd() to be used similarly to arm and x86.
      
      (Can mmap ASLR be safely enabled in the legacy mmap case here?  Other
      archs use "mm->mmap_base = TASK_UNMAPPED_BASE + random_factor".)
      Signed-off-by: default avatarKees Cook <keescook@chromium.org>
      Reviewed-by: default avatarIngo Molnar <mingo@kernel.org>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Cc: Paul Mackerras <paulus@samba.org>
      Cc: Michael Ellerman <mpe@ellerman.id.au>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
      e108721a