1. 15 Apr, 2019 22 commits
  2. 14 Apr, 2019 6 commits
    • Linus Torvalds's avatar
      Linux 5.1-rc5 · dc4060a5
      Linus Torvalds authored
      dc4060a5
    • Linus Torvalds's avatar
      Merge branch 'page-refs' (page ref overflow) · 6b3a7077
      Linus Torvalds authored
      Merge page ref overflow branch.
      
      Jann Horn reported that he can overflow the page ref count with
      sufficient memory (and a filesystem that is intentionally extremely
      slow).
      
      Admittedly it's not exactly easy.  To have more than four billion
      references to a page requires a minimum of 32GB of kernel memory just
      for the pointers to the pages, much less any metadata to keep track of
      those pointers.  Jann needed a total of 140GB of memory and a specially
      crafted filesystem that leaves all reads pending (in order to not ever
      free the page references and just keep adding more).
      
      Still, we have a fairly straightforward way to limit the two obvious
      user-controllable sources of page references: direct-IO like page
      references gotten through get_user_pages(), and the splice pipe page
      duplication.  So let's just do that.
      
      * branch page-refs:
        fs: prevent page refcount overflow in pipe_buf_get
        mm: prevent get_user_pages() from overflowing page refcount
        mm: add 'try_get_page()' helper function
        mm: make page ref count overflow check tighter and more explicit
      6b3a7077
    • Matthew Wilcox's avatar
      fs: prevent page refcount overflow in pipe_buf_get · 15fab63e
      Matthew Wilcox authored
      Change pipe_buf_get() to return a bool indicating whether it succeeded
      in raising the refcount of the page (if the thing in the pipe is a page).
      This removes another mechanism for overflowing the page refcount.  All
      callers converted to handle a failure.
      Reported-by: default avatarJann Horn <jannh@google.com>
      Signed-off-by: default avatarMatthew Wilcox <willy@infradead.org>
      Cc: stable@kernel.org
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      15fab63e
    • Linus Torvalds's avatar
      mm: prevent get_user_pages() from overflowing page refcount · 8fde12ca
      Linus Torvalds authored
      If the page refcount wraps around past zero, it will be freed while
      there are still four billion references to it.  One of the possible
      avenues for an attacker to try to make this happen is by doing direct IO
      on a page multiple times.  This patch makes get_user_pages() refuse to
      take a new page reference if there are already more than two billion
      references to the page.
      Reported-by: default avatarJann Horn <jannh@google.com>
      Acked-by: default avatarMatthew Wilcox <willy@infradead.org>
      Cc: stable@kernel.org
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      8fde12ca
    • Linus Torvalds's avatar
      mm: add 'try_get_page()' helper function · 88b1a17d
      Linus Torvalds authored
      This is the same as the traditional 'get_page()' function, but instead
      of unconditionally incrementing the reference count of the page, it only
      does so if the count was "safe".  It returns whether the reference count
      was incremented (and is marked __must_check, since the caller obviously
      has to be aware of it).
      
      Also like 'get_page()', you can't use this function unless you already
      had a reference to the page.  The intent is that you can use this
      exactly like get_page(), but in situations where you want to limit the
      maximum reference count.
      
      The code currently does an unconditional WARN_ON_ONCE() if we ever hit
      the reference count issues (either zero or negative), as a notification
      that the conditional non-increment actually happened.
      
      NOTE! The count access for the "safety" check is inherently racy, but
      that doesn't matter since the buffer we use is basically half the range
      of the reference count (ie we look at the sign of the count).
      Acked-by: default avatarMatthew Wilcox <willy@infradead.org>
      Cc: Jann Horn <jannh@google.com>
      Cc: stable@kernel.org
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      88b1a17d
    • Linus Torvalds's avatar
      mm: make page ref count overflow check tighter and more explicit · f958d7b5
      Linus Torvalds authored
      We have a VM_BUG_ON() to check that the page reference count doesn't
      underflow (or get close to overflow) by checking the sign of the count.
      
      That's all fine, but we actually want to allow people to use a "get page
      ref unless it's already very high" helper function, and we want that one
      to use the sign of the page ref (without triggering this VM_BUG_ON).
      
      Change the VM_BUG_ON to only check for small underflows (or _very_ close
      to overflowing), and ignore overflows which have strayed into negative
      territory.
      Acked-by: default avatarMatthew Wilcox <willy@infradead.org>
      Cc: Jann Horn <jannh@google.com>
      Cc: stable@kernel.org
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      f958d7b5
  3. 13 Apr, 2019 12 commits
    • Linus Torvalds's avatar
      Merge tag 'for-linus-20190412' of git://git.kernel.dk/linux-block · 4443f8e6
      Linus Torvalds authored
      Pull block fixes from Jens Axboe:
       "Set of fixes that should go into this round. This pull is larger than
        I'd like at this time, but there's really no specific reason for that.
        Some are fixes for issues that went into this merge window, others are
        not. Anyway, this contains:
      
         - Hardware queue limiting for virtio-blk/scsi (Dongli)
      
         - Multi-page bvec fixes for lightnvm pblk
      
         - Multi-bio dio error fix (Jason)
      
         - Remove the cache hint from the io_uring tool side, since we didn't
           move forward with that (me)
      
         - Make io_uring SETUP_SQPOLL root restricted (me)
      
         - Fix leak of page in error handling for pc requests (Jérôme)
      
         - Fix BFQ regression introduced in this merge window (Paolo)
      
         - Fix break logic for bio segment iteration (Ming)
      
         - Fix NVMe cancel request error handling (Ming)
      
         - NVMe pull request with two fixes (Christoph):
             - fix the initial CSN for nvme-fc (James)
             - handle log page offsets properly in the target (Keith)"
      
      * tag 'for-linus-20190412' of git://git.kernel.dk/linux-block:
        block: fix the return errno for direct IO
        nvmet: fix discover log page when offsets are used
        nvme-fc: correct csn initialization and increments on error
        block: do not leak memory in bio_copy_user_iov()
        lightnvm: pblk: fix crash in pblk_end_partial_read due to multipage bvecs
        nvme: cancel request synchronously
        blk-mq: introduce blk_mq_complete_request_sync()
        scsi: virtio_scsi: limit number of hw queues by nr_cpu_ids
        virtio-blk: limit number of hw queues by nr_cpu_ids
        block, bfq: fix use after free in bfq_bfqq_expire
        io_uring: restrict IORING_SETUP_SQPOLL to root
        tools/io_uring: remove IOCQE_FLAG_CACHEHIT
        block: don't use for-inside-for in bio_for_each_segment_all
      4443f8e6
    • Linus Torvalds's avatar
      Merge tag 'nfs-for-5.1-4' of git://git.linux-nfs.org/projects/trondmy/linux-nfs · b60bc066
      Linus Torvalds authored
      Pull NFS client bugfixes from Trond Myklebust:
       "Highlights include:
      
        Stable fix:
      
         - Fix a deadlock in close() due to incorrect draining of RDMA queues
      
        Bugfixes:
      
         - Revert "SUNRPC: Micro-optimise when the task is known not to be
           sleeping" as it is causing stack overflows
      
         - Fix a regression where NFSv4 getacl and fs_locations stopped
           working
      
         - Forbid setting AF_INET6 to "struct sockaddr_in"->sin_family.
      
         - Fix xfstests failures due to incorrect copy_file_range() return
           values"
      
      * tag 'nfs-for-5.1-4' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
        Revert "SUNRPC: Micro-optimise when the task is known not to be sleeping"
        NFSv4.1 fix incorrect return value in copy_file_range
        xprtrdma: Fix helper that drains the transport
        NFS: Fix handling of reply page vector
        NFS: Forbid setting AF_INET6 to "struct sockaddr_in"->sin_family.
      b60bc066
    • Linus Torvalds's avatar
      Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi · 87af0c38
      Linus Torvalds authored
      Pull SCSI fix from James Bottomley:
       "One obvious fix for a ciostor data corruption on error bug"
      
      * tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
        scsi: csiostor: fix missing data copy in csio_scsi_err_handler()
      87af0c38
    • Linus Torvalds's avatar
      Merge tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux · 09bad0df
      Linus Torvalds authored
      Pull clk fixes from Stephen Boyd:
       "Here's more than a handful of clk driver fixes for changes that came
        in during the merge window:
      
         - Fix the AT91 sama5d2 programmable clk prescaler formula
      
         - A bunch of Amlogic meson clk driver fixes for the VPU clks
      
         - A DMI quirk for Intel's Bay Trail SoC's driver to properly mark pmc
           clks as critical only when really needed
      
         - Stop overwriting CLK_SET_RATE_PARENT flag in mediatek's clk gate
           implementation
      
         - Use the right structure to test for a frequency table in i.MX's
           PLL_1416x driver"
      
      * tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
        clk: imx: Fix PLL_1416X not rounding rates
        clk: mediatek: fix clk-gate flag setting
        platform/x86: pmc_atom: Drop __initconst on dmi table
        clk: x86: Add system specific quirk to mark clocks as critical
        clk: meson: vid-pll-div: remove warning and return 0 on invalid config
        clk: meson: pll: fix rounding and setting a rate that matches precisely
        clk: meson-g12a: fix VPU clock parents
        clk: meson: g12a: fix VPU clock muxes mask
        clk: meson-gxbb: round the vdec dividers to closest
        clk: at91: fix programmable clock for sama5d2
      09bad0df
    • Linus Torvalds's avatar
      Merge tag 'pci-v5.1-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci · a3b84248
      Linus Torvalds authored
      Pull PCI fixes from Bjorn Helgaas:
      
       - Add a DMA alias quirk for another Marvell SATA device (Andre
         Przywara)
      
       - Fix a pciehp regression that broke safe removal of devices (Sergey
         Miroshnichenko)
      
      * tag 'pci-v5.1-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
        PCI: pciehp: Ignore Link State Changes after powering off a slot
        PCI: Add function 1 DMA alias quirk for Marvell 9170 SATA controller
      a3b84248
    • Linus Torvalds's avatar
      Merge tag 'powerpc-5.1-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux · cf60528f
      Linus Torvalds authored
      Pull powerpc fixes from Michael Ellerman:
       "A minor build fix for 64-bit FLATMEM configs.
      
        A fix for a boot failure on 32-bit powermacs.
      
        My commit to fix CLOCK_MONOTONIC across Y2038 broke the 32-bit VDSO on
        64-bit kernels, ie. compat mode, which is only used on big endian.
      
        The rewrite of the SLB code we merged in 4.20 missed the fact that the
        0x380 exception is also used with the Radix MMU to report out of range
        accesses. This could lead to an oops if userspace tried to read from
        addresses outside the user or kernel range.
      
        Thanks to: Aneesh Kumar K.V, Christophe Leroy, Larry Finger, Nicholas
        Piggin"
      
      * tag 'powerpc-5.1-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
        powerpc/mm: Define MAX_PHYSMEM_BITS for all 64-bit configs
        powerpc/64s/radix: Fix radix segment exception handling
        powerpc/vdso32: fix CLOCK_MONOTONIC on PPC64
        powerpc/32: Fix early boot failure with RTAS built-in
      cf60528f
    • Linus Torvalds's avatar
      Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux · 5ded8871
      Linus Torvalds authored
      Pull arm64 fixes from Will Deacon:
       "The main thing is a fix to our FUTEX_WAKE_OP implementation which was
        unbelievably broken, but did actually work for the one scenario that
        GLIBC used to use.
      
        Summary:
      
         - Fix stack unwinding so we ignore user stacks
      
         - Fix ftrace module PLT trampoline initialisation checks
      
         - Fix terminally broken implementation of FUTEX_WAKE_OP atomics"
      
      * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
        arm64: futex: Fix FUTEX_WAKE_OP atomic ops with non-zero result value
        arm64: backtrace: Don't bother trying to unwind the userspace stack
        arm64/ftrace: fix inadvertent BUG() in trampoline check
      5ded8871
    • Linus Torvalds's avatar
      Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · 6d0a5984
      Linus Torvalds authored
      Pull x86 fixes from Ingo Molnar:
       "Fix typos in user-visible resctrl parameters, and also fix assembly
        constraint bugs that might result in miscompilation"
      
      * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
        x86/asm: Use stricter assembly constraints in bitops
        x86/resctrl: Fix typos in the mba_sc mount option
      6d0a5984
    • Linus Torvalds's avatar
      Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · 122c215b
      Linus Torvalds authored
      Pull timer fix from Ingo Molnar:
       "Fix the alarm_timer_remaining() return value"
      
      * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
        alarmtimer: Return correct remaining time
      122c215b
    • Linus Torvalds's avatar
      Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · 5e6f1fee
      Linus Torvalds authored
      Pull scheduler fix from Ingo Molnar:
       "Fix a NULL pointer dereference crash in certain environments"
      
      * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
        sched/fair: Do not re-read ->h_load_next during hierarchical load calculation
      5e6f1fee
    • Linus Torvalds's avatar
      Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · 73fdb2c9
      Linus Torvalds authored
      Pull perf fixes from Ingo Molnar:
       "Six kernel side fixes: three related to NMI handling on AMD systems, a
        race fix, a kexec initialization fix and a PEBS sampling fix"
      
      * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
        perf/core: Fix perf_event_disable_inatomic() race
        x86/perf/amd: Remove need to check "running" bit in NMI handler
        x86/perf/amd: Resolve NMI latency issues for active PMCs
        x86/perf/amd: Resolve race condition when disabling PMC
        perf/x86/intel: Initialize TFA MSR
        perf/x86/intel: Fix handling of wakeup_events for multi-entry PEBS
      73fdb2c9
    • Linus Torvalds's avatar
      Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · 26e2b819
      Linus Torvalds authored
      Pull locking fix from Ingo Molnar:
       "Fixes a crash when accessing /proc/lockdep"
      
      * 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
        locking/lockdep: Zap lock classes even with lock debugging disabled
      26e2b819