1. 14 1月, 2017 1 次提交
    • P
      efi/x86: Prune invalid memory map entries and fix boot regression · 0100a3e6
      Peter Jones 提交于
      Some machines, such as the Lenovo ThinkPad W541 with firmware GNET80WW
      (2.28), include memory map entries with phys_addr=0x0 and num_pages=0.
      
      These machines fail to boot after the following commit,
      
        commit 8e80632f ("efi/esrt: Use efi_mem_reserve() and avoid a kmalloc()")
      
      Fix this by removing such bogus entries from the memory map.
      
      Furthermore, currently the log output for this case (with efi=debug)
      looks like:
      
       [    0.000000] efi: mem45: [Reserved           |   |  |  |  |  |  |  |  |  |  |  |  ] range=[0x0000000000000000-0xffffffffffffffff] (0MB)
      
      This is clearly wrong, and also not as informative as it could be.  This
      patch changes it so that if we find obviously invalid memory map
      entries, we print an error and skip those entries.  It also detects the
      display of the address range calculation overflow, so the new output is:
      
       [    0.000000] efi: [Firmware Bug]: Invalid EFI memory map entries:
       [    0.000000] efi: mem45: [Reserved           |   |  |  |  |  |  |  |   |  |  |  |  ] range=[0x0000000000000000-0x0000000000000000] (invalid)
      
      It also detects memory map sizes that would overflow the physical
      address, for example phys_addr=0xfffffffffffff000 and
      num_pages=0x0200000000000001, and prints:
      
       [    0.000000] efi: [Firmware Bug]: Invalid EFI memory map entries:
       [    0.000000] efi: mem45: [Reserved           |   |  |  |  |  |  |  |   |  |  |  |  ] range=[phys_addr=0xfffffffffffff000-0x20ffffffffffffffff] (invalid)
      
      It then removes these entries from the memory map.
      Signed-off-by: NPeter Jones <pjones@redhat.com>
      Signed-off-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
      [ardb: refactor for clarity with no functional changes, avoid PAGE_SHIFT]
      Signed-off-by: NMatt Fleming <matt@codeblueprint.co.uk>
      [Matt: Include bugzilla info in commit log]
      Cc: <stable@vger.kernel.org> # v4.9+
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Link: https://bugzilla.kernel.org/show_bug.cgi?id=191121Signed-off-by: NIngo Molnar <mingo@kernel.org>
      0100a3e6
  2. 13 1月, 2017 1 次提交
  3. 12 1月, 2017 4 次提交
    • P
      KVM: x86: fix emulation of "MOV SS, null selector" · 33ab9110
      Paolo Bonzini 提交于
      This is CVE-2017-2583.  On Intel this causes a failed vmentry because
      SS's type is neither 3 nor 7 (even though the manual says this check is
      only done for usable SS, and the dmesg splat says that SS is unusable!).
      On AMD it's worse: svm.c is confused and sets CPL to 0 in the vmcb.
      
      The fix fabricates a data segment descriptor when SS is set to a null
      selector, so that CPL and SS.DPL are set correctly in the VMCS/vmcb.
      Furthermore, only allow setting SS to a NULL selector if SS.RPL < 3;
      this in turn ensures CPL < 3 because RPL must be equal to CPL.
      
      Thanks to Andy Lutomirski and Willy Tarreau for help in analyzing
      the bug and deciphering the manuals.
      Reported-by: NXiaohan Zhang <zhangxiaohan1@huawei.com>
      Fixes: 79d5b4c3
      Cc: stable@nongnu.org
      Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      33ab9110
    • W
      KVM: x86: fix NULL deref in vcpu_scan_ioapic · 546d87e5
      Wanpeng Li 提交于
      Reported by syzkaller:
      
          BUG: unable to handle kernel NULL pointer dereference at 00000000000001b0
          IP: _raw_spin_lock+0xc/0x30
          PGD 3e28eb067
          PUD 3f0ac6067
          PMD 0
          Oops: 0002 [#1] SMP
          CPU: 0 PID: 2431 Comm: test Tainted: G           OE   4.10.0-rc1+ #3
          Call Trace:
           ? kvm_ioapic_scan_entry+0x3e/0x110 [kvm]
           kvm_arch_vcpu_ioctl_run+0x10a8/0x15f0 [kvm]
           ? pick_next_task_fair+0xe1/0x4e0
           ? kvm_arch_vcpu_load+0xea/0x260 [kvm]
           kvm_vcpu_ioctl+0x33a/0x600 [kvm]
           ? hrtimer_try_to_cancel+0x29/0x130
           ? do_nanosleep+0x97/0xf0
           do_vfs_ioctl+0xa1/0x5d0
           ? __hrtimer_init+0x90/0x90
           ? do_nanosleep+0x5b/0xf0
           SyS_ioctl+0x79/0x90
           do_syscall_64+0x6e/0x180
           entry_SYSCALL64_slow_path+0x25/0x25
          RIP: _raw_spin_lock+0xc/0x30 RSP: ffffa43688973cc0
      
      The syzkaller folks reported a NULL pointer dereference due to
      ENABLE_CAP succeeding even without an irqchip.  The Hyper-V
      synthetic interrupt controller is activated, resulting in a
      wrong request to rescan the ioapic and a NULL pointer dereference.
      
          #include <sys/ioctl.h>
          #include <sys/mman.h>
          #include <sys/types.h>
          #include <linux/kvm.h>
          #include <pthread.h>
          #include <stddef.h>
          #include <stdint.h>
          #include <stdlib.h>
          #include <string.h>
          #include <unistd.h>
      
          #ifndef KVM_CAP_HYPERV_SYNIC
          #define KVM_CAP_HYPERV_SYNIC 123
          #endif
      
          void* thr(void* arg)
          {
      	struct kvm_enable_cap cap;
      	cap.flags = 0;
      	cap.cap = KVM_CAP_HYPERV_SYNIC;
      	ioctl((long)arg, KVM_ENABLE_CAP, &cap);
      	return 0;
          }
      
          int main()
          {
      	void *host_mem = mmap(0, 0x1000, PROT_READ|PROT_WRITE,
      			MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
      	int kvmfd = open("/dev/kvm", 0);
      	int vmfd = ioctl(kvmfd, KVM_CREATE_VM, 0);
      	struct kvm_userspace_memory_region memreg;
      	memreg.slot = 0;
      	memreg.flags = 0;
      	memreg.guest_phys_addr = 0;
      	memreg.memory_size = 0x1000;
      	memreg.userspace_addr = (unsigned long)host_mem;
      	host_mem[0] = 0xf4;
      	ioctl(vmfd, KVM_SET_USER_MEMORY_REGION, &memreg);
      	int cpufd = ioctl(vmfd, KVM_CREATE_VCPU, 0);
      	struct kvm_sregs sregs;
      	ioctl(cpufd, KVM_GET_SREGS, &sregs);
      	sregs.cr0 = 0;
      	sregs.cr4 = 0;
      	sregs.efer = 0;
      	sregs.cs.selector = 0;
      	sregs.cs.base = 0;
      	ioctl(cpufd, KVM_SET_SREGS, &sregs);
      	struct kvm_regs regs = { .rflags = 2 };
      	ioctl(cpufd, KVM_SET_REGS, &regs);
      	ioctl(vmfd, KVM_CREATE_IRQCHIP, 0);
      	pthread_t th;
      	pthread_create(&th, 0, thr, (void*)(long)cpufd);
      	usleep(rand() % 10000);
      	ioctl(cpufd, KVM_RUN, 0);
      	pthread_join(th, 0);
      	return 0;
          }
      
      This patch fixes it by failing ENABLE_CAP if without an irqchip.
      Reported-by: NDmitry Vyukov <dvyukov@google.com>
      Fixes: 5c919412 (kvm/x86: Hyper-V synthetic interrupt controller)
      Cc: stable@vger.kernel.org # 4.5+
      Cc: Paolo Bonzini <pbonzini@redhat.com>
      Cc: Radim Krčmář <rkrcmar@redhat.com>
      Cc: Dmitry Vyukov <dvyukov@google.com>
      Signed-off-by: NWanpeng Li <wanpeng.li@hotmail.com>
      Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      546d87e5
    • S
      KVM: x86: Introduce segmented_write_std · 129a72a0
      Steve Rutherford 提交于
      Introduces segemented_write_std.
      
      Switches from emulated reads/writes to standard read/writes in fxsave,
      fxrstor, sgdt, and sidt.  This fixes CVE-2017-2584, a longstanding
      kernel memory leak.
      
      Since commit 283c95d0 ("KVM: x86: emulate FXSAVE and FXRSTOR",
      2016-11-09), which is luckily not yet in any final release, this would
      also be an exploitable kernel memory *write*!
      Reported-by: NDmitry Vyukov <dvyukov@google.com>
      Cc: stable@vger.kernel.org
      Fixes: 96051572
      Fixes: 283c95d0Suggested-by: NPaolo Bonzini <pbonzini@redhat.com>
      Signed-off-by: NSteve Rutherford <srutherford@google.com>
      Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      129a72a0
    • D
      KVM: x86: flush pending lapic jump label updates on module unload · cef84c30
      David Matlack 提交于
      KVM's lapic emulation uses static_key_deferred (apic_{hw,sw}_disabled).
      These are implemented with delayed_work structs which can still be
      pending when the KVM module is unloaded. We've seen this cause kernel
      panics when the kvm_intel module is quickly reloaded.
      
      Use the new static_key_deferred_flush() API to flush pending updates on
      module unload.
      Signed-off-by: NDavid Matlack <dmatlack@google.com>
      Cc: stable@vger.kernel.org
      Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      cef84c30
  4. 11 1月, 2017 1 次提交
  5. 09 1月, 2017 1 次提交
  6. 07 1月, 2017 1 次提交
    • N
      x86/efi: Don't allocate memmap through memblock after mm_init() · 20b1e22d
      Nicolai Stange 提交于
      With the following commit:
      
        4bc9f92e ("x86/efi-bgrt: Use efi_mem_reserve() to avoid copying image data")
      
      ...  efi_bgrt_init() calls into the memblock allocator through
      efi_mem_reserve() => efi_arch_mem_reserve() *after* mm_init() has been called.
      
      Indeed, KASAN reports a bad read access later on in efi_free_boot_services():
      
        BUG: KASAN: use-after-free in efi_free_boot_services+0xae/0x24c
                  at addr ffff88022de12740
        Read of size 4 by task swapper/0/0
        page:ffffea0008b78480 count:0 mapcount:-127
        mapping:          (null) index:0x1 flags: 0x5fff8000000000()
        [...]
        Call Trace:
         dump_stack+0x68/0x9f
         kasan_report_error+0x4c8/0x500
         kasan_report+0x58/0x60
         __asan_load4+0x61/0x80
         efi_free_boot_services+0xae/0x24c
         start_kernel+0x527/0x562
         x86_64_start_reservations+0x24/0x26
         x86_64_start_kernel+0x157/0x17a
         start_cpu+0x5/0x14
      
      The instruction at the given address is the first read from the memmap's
      memory, i.e. the read of md->type in efi_free_boot_services().
      
      Note that the writes earlier in efi_arch_mem_reserve() don't splat because
      they're done through early_memremap()ed addresses.
      
      So, after memblock is gone, allocations should be done through the "normal"
      page allocator. Introduce a helper, efi_memmap_alloc() for this. Use
      it from efi_arch_mem_reserve(), efi_free_boot_services() and, for the sake
      of consistency, from efi_fake_memmap() as well.
      
      Note that for the latter, the memmap allocations cease to be page aligned.
      This isn't needed though.
      Tested-by: NDan Williams <dan.j.williams@intel.com>
      Signed-off-by: NNicolai Stange <nicstange@gmail.com>
      Reviewed-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
      Cc: <stable@vger.kernel.org> # v4.9
      Cc: Dave Young <dyoung@redhat.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Matt Fleming <matt@codeblueprint.co.uk>
      Cc: Mika Penttilä <mika.penttila@nextfour.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: linux-efi@vger.kernel.org
      Fixes: 4bc9f92e ("x86/efi-bgrt: Use efi_mem_reserve() to avoid copying image data")
      Link: http://lkml.kernel.org/r/20170105125130.2815-1-nicstange@gmail.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
      20b1e22d
  7. 05 1月, 2017 5 次提交
    • J
      KVM: VMX: remove duplicated declaration · 69130ea1
      Jan Dakinevich 提交于
      Declaration of VMX_VPID_EXTENT_SUPPORTED_MASK occures twice in the code.
      Probably, it was happened after unsuccessful merge.
      Signed-off-by: NJan Dakinevich <jan.dakinevich@gmail.com>
      Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>
      69130ea1
    • J
      KVM: MIPS: Flush KVM entry code from icache globally · 32eb12a6
      James Hogan 提交于
      Flush the KVM entry code from the icache on all CPUs, not just the one
      that built the entry code.
      Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
      Cc: Paolo Bonzini <pbonzini@redhat.com>
      Cc: "Radim Krčmář" <rkrcmar@redhat.com>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: linux-mips@linux-mips.org
      Cc: kvm@vger.kernel.org
      Cc: <stable@vger.kernel.org> # 3.16.x-
      Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>
      32eb12a6
    • J
      KVM: MIPS: Don't clobber CP0_Status.UX · 4c881451
      James Hogan 提交于
      On 64-bit kernels, MIPS KVM will clear CP0_Status.UX to prevent the
      guest (running in user mode) from accessing the 64-bit memory segments.
      However the previous value of CP0_Status.UX is never restored when
      exiting from the guest.
      
      If the user process uses 64-bit addressing (the n64 ABI) this can result
      in address error exceptions from the kernel if it needs to deliver a
      signal before returning to user mode, as the kernel will need to write a
      sigframe to high user addresses on the user stack which are disallowed
      by CP0_Status.UX=0.
      
      This is fixed by explicitly setting SX and UX again when exiting from
      the guest, and explicitly clearing those bits when returning to the
      guest. Having the SX and UX bits set when handling guest exits (rather
      than only when exiting to userland) will be helpful when we support VZ,
      since we shouldn't need to directly read or write guest memory, so it
      will be valid for cache management IPIs to access host user addresses.
      Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
      Cc: Paolo Bonzini <pbonzini@redhat.com>
      Cc: "Radim Krčmář" <rkrcmar@redhat.com>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: linux-mips@linux-mips.org
      Cc: kvm@vger.kernel.org
      Cc: <stable@vger.kernel.org> # 4.8.x-
      Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>
      4c881451
    • M
      arm64: restore get_current() optimisation · 9d84fb27
      Mark Rutland 提交于
      Commit c02433dd ("arm64: split thread_info from task stack")
      inverted the relationship between get_current() and
      current_thread_info(), with sp_el0 now holding the current task_struct
      rather than the current thead_info. The new implementation of
      get_current() prevents the compiler from being able to optimize repeated
      calls to either, resulting in a noticeable penalty in some
      microbenchmarks.
      
      This patch restores the previous optimisation by implementing
      get_current() in the same way as our old current_thread_info(), using a
      non-volatile asm statement.
      Acked-by: NWill Deacon <will.deacon@arm.com>
      Signed-off-by: NMark Rutland <mark.rutland@arm.com>
      Reported-by: NDavidlohr Bueso <dbueso@suse.de>
      Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
      9d84fb27
    • M
      arm64: mm: fix show_pte KERN_CONT fallout · 6ef4fb38
      Mark Rutland 提交于
      Recent changes made KERN_CONT mandatory for continued lines. In the
      absence of KERN_CONT, a newline may be implicit inserted by the core
      printk code.
      
      In show_pte, we (erroneously) use printk without KERN_CONT for continued
      prints, resulting in output being split across a number of lines, and
      not matching the intended output, e.g.
      
      [ff000000000000] *pgd=00000009f511b003
      , *pud=00000009f4a80003
      , *pmd=0000000000000000
      
      Fix this by using pr_cont() for all the continuations.
      Acked-by: NWill Deacon <will.deacon@arm.com>
      Signed-off-by: NMark Rutland <mark.rutland@arm.com>
      Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
      6ef4fb38
  8. 04 1月, 2017 3 次提交
  9. 03 1月, 2017 3 次提交
  10. 02 1月, 2017 9 次提交
  11. 31 12月, 2016 1 次提交
  12. 30 12月, 2016 6 次提交
    • S
      arm64: dts: vexpress: Support GICC_DIR operations · 1dff32d7
      Sudeep Holla 提交于
      The GICv2 CPU interface registers span across 8K, not 4K as indicated in
      the DT.  Only the GICC_DIR register is located after the initial 4K
      boundary, leaving a functional system but without support for separately
      EOI'ing and deactivating interrupts.
      
      After this change the system supports split priority drop and interrupt
      deactivation. This patch is based on similar one from Christoffer Dall:
      commit 368400e2 ("ARM: dts: vexpress: Support GICC_DIR operations")
      Signed-off-by: NSudeep Holla <sudeep.holla@arm.com>
      1dff32d7
    • C
      ARM: dts: vexpress: Support GICC_DIR operations · 368400e2
      Christoffer Dall 提交于
      The GICv2 CPU interface registers span across 8K, not 4K as indicated in
      the DT.  Only the GICC_DIR register is located after the initial 4K
      boundary, leaving a functional system but without support for separately
      EOI'ing and deactivating interrupts.
      
      After this change the system supports split priority drop and interrupt
      deactivation.
      Acked-by: NMarc Zyngier <marc.zyngier@arm.com>
      Signed-off-by: NChristoffer Dall <christoffer.dall@linaro.org>
      [sudeep.holla@arm.com: included same fix for tc1 platform too]
      Signed-off-by: NSudeep Holla <sudeep.holla@arm.com>
      368400e2
    • H
      crypto: aesni - Fix failure when built-in with modular pcbc · 07825f0a
      Herbert Xu 提交于
      If aesni is built-in but pcbc is built as a module, then aesni
      will fail completely because when it tries to register the pcbc
      variant of aes the pcbc template is not available.
      
      This patch fixes this by modifying the pcbc presence test so that
      if aesni is built-in then pcbc must also be built-in for it to be
      used by aesni.
      
      Fixes: 85671860 ("crypto: aesni - Convert to skcipher")
      Reported-by: NStephan Müller <smueller@chronox.de>
      Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
      07825f0a
    • H
      parisc: Drop TIF_RESTORE_SIGMASK and switch to generic code · 1fe0a7e0
      Helge Deller 提交于
      Commit 7e781418 ("signal: consolidate {TS,TLF}_RESTORE_SIGMASK code")
      introduced code with which the "restore sigmask" flag lives in task_struct
      instead of ti->flags. Let's use this optimization on parisc too.
      Signed-off-by: NHelge Deller <deller@gmx.de>
      1fe0a7e0
    • H
      parisc: Mark cr16 clocksource unstable on SMP systems · 41744213
      Helge Deller 提交于
      The cr16 interval timer of each CPU is not syncronized to other cr16
      timers in other CPUs in a SMP system. So, delay the registration of the
      cr16 clocksource until all CPUs have been detected and then - if we are
      on a SMP machine - mark the cr16 clocksource as unstable and lower it's
      rating before registering it at the clocksource framework.
      
      This patch fixes the stalled CPU warnings which we have seen since
      introduction of the cr16 clocksource.
      Signed-off-by: NHelge Deller <deller@gmx.de>
      Cc: <stable@vger.kernel.org> # v4.8+
      41744213
    • L
      mm: optimize PageWaiters bit use for unlock_page() · b91e1302
      Linus Torvalds 提交于
      In commit 62906027 ("mm: add PageWaiters indicating tasks are
      waiting for a page bit") Nick Piggin made our page locking no longer
      unconditionally touch the hashed page waitqueue, which not only helps
      performance in general, but is particularly helpful on NUMA machines
      where the hashed wait queues can bounce around a lot.
      
      However, the "clear lock bit atomically and then test the waiters bit"
      sequence turns out to be much more expensive than it needs to be,
      because you get a nasty stall when trying to access the same word that
      just got updated atomically.
      
      On architectures where locking is done with LL/SC, this would be trivial
      to fix with a new primitive that clears one bit and tests another
      atomically, but that ends up not working on x86, where the only atomic
      operations that return the result end up being cmpxchg and xadd.  The
      atomic bit operations return the old value of the same bit we changed,
      not the value of an unrelated bit.
      
      On x86, we could put the lock bit in the high bit of the byte, and use
      "xadd" with that bit (where the overflow ends up not touching other
      bits), and look at the other bits of the result.  However, an even
      simpler model is to just use a regular atomic "and" to clear the lock
      bit, and then the sign bit in eflags will indicate the resulting state
      of the unrelated bit #7.
      
      So by moving the PageWaiters bit up to bit #7, we can atomically clear
      the lock bit and test the waiters bit on x86 too.  And architectures
      with LL/SC (which is all the usual RISC suspects), the particular bit
      doesn't matter, so they are fine with this approach too.
      
      This avoids the extra access to the same atomic word, and thus avoids
      the costly stall at page unlock time.
      
      The only downside is that the interface ends up being a bit odd and
      specialized: clear a bit in a byte, and test the sign bit.  Nick doesn't
      love the resulting name of the new primitive, but I'd rather make the
      name be descriptive and very clear about the limitation imposed by
      trying to work across all relevant architectures than make it be some
      generic thing that doesn't make the odd semantics explicit.
      
      So this introduces the new architecture primitive
      
          clear_bit_unlock_is_negative_byte();
      
      and adds the trivial implementation for x86.  We have a generic
      non-optimized fallback (that just does a "clear_bit()"+"test_bit(7)"
      combination) which can be overridden by any architecture that can do
      better.  According to Nick, Power has the same hickup x86 has, for
      example, but some other architectures may not even care.
      
      All these optimizations mean that my page locking stress-test (which is
      just executing a lot of small short-lived shell scripts: "make test" in
      the git source tree) no longer makes our page locking look horribly bad.
      Before all these optimizations, just the unlock_page() costs were just
      over 3% of all CPU overhead on "make test".  After this, it's down to
      0.66%, so just a quarter of the cost it used to be.
      
      (The difference on NUMA is bigger, but there this micro-optimization is
      likely less noticeable, since the big issue on NUMA was not the accesses
      to 'struct page', but the waitqueue accesses that were already removed
      by Nick's earlier commit).
      Acked-by: NNick Piggin <npiggin@gmail.com>
      Cc: Dave Hansen <dave.hansen@linux.intel.com>
      Cc: Bob Peterson <rpeterso@redhat.com>
      Cc: Steven Whitehouse <swhiteho@redhat.com>
      Cc: Andrew Lutomirski <luto@kernel.org>
      Cc: Andreas Gruenbacher <agruenba@redhat.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Mel Gorman <mgorman@techsingularity.net>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      b91e1302
  13. 29 12月, 2016 1 次提交
  14. 28 12月, 2016 3 次提交