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2016-12-25Merge branch 'timers-urgent-for-linus' of ↵Linus Torvalds1-4/+4
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer type cleanups from Thomas Gleixner: "This series does a tree wide cleanup of types related to timers/timekeeping. - Get rid of cycles_t and use a plain u64. The type is not really helpful and caused more confusion than clarity - Get rid of the ktime union. The union has become useless as we use the scalar nanoseconds storage unconditionally now. The 32bit timespec alike storage got removed due to the Y2038 limitations some time ago. That leaves the odd union access around for no reason. Clean it up. Both changes have been done with coccinelle and a small amount of manual mopping up" * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: ktime: Get rid of ktime_equal() ktime: Cleanup ktime_set() usage ktime: Get rid of the union clocksource: Use a plain u64 instead of cycle_t
2016-12-25clocksource: Use a plain u64 instead of cycle_tThomas Gleixner1-4/+4
There is no point in having an extra type for extra confusion. u64 is unambiguous. Conversion was done with the following coccinelle script: @rem@ @@ -typedef u64 cycle_t; @fix@ typedef cycle_t; @@ -cycle_t +u64 Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: John Stultz <john.stultz@linaro.org>
2016-12-25cpu/hotplug: Cleanup state namesThomas Gleixner1-1/+1
When the state names got added a script was used to add the extra argument to the calls. The script basically converted the state constant to a string, but the cleanup to convert these strings into meaningful ones did not happen. Replace all the useless strings with 'subsys/xxx/yyy:state' strings which are used in all the other places already. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sebastian Siewior <bigeasy@linutronix.de> Link: http://lkml.kernel.org/r/20161221192112.085444152@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-14mm: use vmf->address instead of of vmf->virtual_addressJan Kara1-2/+2
Every single user of vmf->virtual_address typed that entry to unsigned long before doing anything with it so the type of virtual_address does not really provide us any additional safety. Just use masked vmf->address which already has the appropriate type. Link: http://lkml.kernel.org/r/1479460644-25076-3-git-send-email-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-28x86/vdso: Set vDSO pointer only after successDmitry Safonov1-7/+3
Those pointers were initialized before call to _install_special_mapping() after the commit: f7b6eb3fa072 ("x86: Set context.vdso before installing the mapping") This is not required anymore as special mappings have their vma name and don't use arch_vma_name() after commit: a62c34bd2a8a ("x86, mm: Improve _install_special_mapping and fix x86 vdso naming") So, this way to init looks less entangled. I even belive that we can remove NULL initializers: - on failure load_elf_binary() will not start a new thread; - arch_prctl will have the same pointers as before syscall. Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: 0x7f454c46@gmail.com Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-mm@kvack.org Cc: oleg@redhat.com Link: http://lkml.kernel.org/r/20161027141516.28447-3-dsafonov@virtuozzo.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-10-06Merge tag 'kvm-4.9-1' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds1-1/+1
Pull KVM updates from Radim Krčmář: "All architectures: - move `make kvmconfig` stubs from x86 - use 64 bits for debugfs stats ARM: - Important fixes for not using an in-kernel irqchip - handle SError exceptions and present them to guests if appropriate - proxying of GICV access at EL2 if guest mappings are unsafe - GICv3 on AArch32 on ARMv8 - preparations for GICv3 save/restore, including ABI docs - cleanups and a bit of optimizations MIPS: - A couple of fixes in preparation for supporting MIPS EVA host kernels - MIPS SMP host & TLB invalidation fixes PPC: - Fix the bug which caused guests to falsely report lockups - other minor fixes - a small optimization s390: - Lazy enablement of runtime instrumentation - up to 255 CPUs for nested guests - rework of machine check deliver - cleanups and fixes x86: - IOMMU part of AMD's AVIC for vmexit-less interrupt delivery - Hyper-V TSC page - per-vcpu tsc_offset in debugfs - accelerated INS/OUTS in nVMX - cleanups and fixes" * tag 'kvm-4.9-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (140 commits) KVM: MIPS: Drop dubious EntryHi optimisation KVM: MIPS: Invalidate TLB by regenerating ASIDs KVM: MIPS: Split kernel/user ASID regeneration KVM: MIPS: Drop other CPU ASIDs on guest MMU changes KVM: arm/arm64: vgic: Don't flush/sync without a working vgic KVM: arm64: Require in-kernel irqchip for PMU support KVM: PPC: Book3s PR: Allow access to unprivileged MMCR2 register KVM: PPC: Book3S PR: Support 64kB page size on POWER8E and POWER8NVL KVM: PPC: Book3S: Remove duplicate setting of the B field in tlbie KVM: PPC: BookE: Fix a sanity check KVM: PPC: Book3S HV: Take out virtual core piggybacking code KVM: PPC: Book3S: Treat VTB as a per-subcore register, not per-thread ARM: gic-v3: Work around definition of gic_write_bpr1 KVM: nVMX: Fix the NMI IDT-vectoring handling KVM: VMX: Enable MSR-BASED TPR shadow even if APICv is inactive KVM: nVMX: Fix reload apic access page warning kvmconfig: add virtio-gpu to config fragment config: move x86 kvm_guest.config to a common location arm64: KVM: Remove duplicating init code for setting VMID ARM: KVM: Support vgic-v3 ...
2016-10-03Merge branch 'x86-vdso-for-linus' of ↵Linus Torvalds1-73/+102
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 vdso updates from Ingo Molnar: "The main changes in this cycle centered around adding support for 32-bit compatible C/R of the vDSO on 64-bit kernels, by Dmitry Safonov" * 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/vdso: Use CONFIG_X86_X32_ABI to enable vdso prctl x86/vdso: Only define map_vdso_randomized() if CONFIG_X86_64 x86/vdso: Only define prctl_map_vdso() if CONFIG_CHECKPOINT_RESTORE x86/signal: Add SA_{X32,IA32}_ABI sa_flags x86/ptrace: Down with test_thread_flag(TIF_IA32) x86/coredump: Use pr_reg size, rather that TIF_IA32 flag x86/arch_prctl/vdso: Add ARCH_MAP_VDSO_* x86/vdso: Replace calculate_addr in map_vdso() with addr x86/vdso: Unmap vdso blob on vvar mapping failure
2016-09-30x86/vdso: Fix building on big endian hostSegher Boessenkool1-1/+1
We need to call GET_LE to read hdr->e_type. Fixes: 57f90c3dfc75 ("x86/vdso: Error out if the vDSO isn't a valid DSO") Reported-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Segher Boessenkool <segher@kernel.crashing.org> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: linux-next@vger.kernel.org Link: http://lkml.kernel.org/r/20160929193442.GA16617@gate.crashing.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-20KVM: x86: introduce get_kvmclock_nsPaolo Bonzini1-1/+1
Introduce a function that reads the exact nanoseconds value that is provided to the guest in kvmclock. This crystallizes the notion of kvmclock as a thin veneer over a stable TSC, that the guest will (hopefully) convert with NTP. In other words, kvmclock is *not* a paravirtualized host-to-guest NTP. Drop the get_kernel_ns() function, that was used both to get the base value of the master clock and to get the current value of kvmclock. The former use is replaced by ktime_get_boot_ns(), the latter is the purpose of get_kernel_ns(). This also allows KVM to provide a Hyper-V time reference counter that is synchronized with the time that is computed from the TSC page. Reviewed-by: Roman Kagan <rkagan@virtuozzo.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-15x86/vdso: Only define map_vdso_randomized() if CONFIG_X86_64Ingo Molnar1-50/+48
... otherwise the compiler complains: arch/x86/entry/vdso/vma.c:252:12: warning: ‘map_vdso_randomized’ defined but not used [-Wunused-function] But the #ifdeffery here is getting pretty ugly, so move around vdso_addr() as well to cluster the dependencies a bit more. It's still not particulary pretty though ... Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Dmitry Safonov <dsafonov@virtuozzo.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: gorcunov@openvz.org Cc: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org Cc: oleg@redhat.com Cc: xemul@virtuozzo.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-14x86/arch_prctl/vdso: Add ARCH_MAP_VDSO_*Dmitry Safonov1-10/+35
Add API to change vdso blob type with arch_prctl. As this is usefull only by needs of CRIU, expose this interface under CONFIG_CHECKPOINT_RESTORE. Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: 0x7f454c46@gmail.com Cc: oleg@redhat.com Cc: linux-mm@kvack.org Cc: gorcunov@openvz.org Cc: xemul@virtuozzo.com Link: http://lkml.kernel.org/r/20160905133308.28234-4-dsafonov@virtuozzo.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-14x86/vdso: Replace calculate_addr in map_vdso() with addrDmitry Safonov1-13/+17
That will allow to specify address where to map vDSO blob. For the randomized vDSO mappings introduce map_vdso_randomized() which will simplify calls to map_vdso. Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: 0x7f454c46@gmail.com Cc: oleg@redhat.com Cc: linux-mm@kvack.org Cc: gorcunov@openvz.org Cc: xemul@virtuozzo.com Link: http://lkml.kernel.org/r/20160905133308.28234-3-dsafonov@virtuozzo.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-14x86/vdso: Unmap vdso blob on vvar mapping failureDmitry Safonov1-2/+4
If remapping of vDSO blob failed on vvar mapping, we need to unmap previously mapped vDSO blob. Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: 0x7f454c46@gmail.com Cc: oleg@redhat.com Cc: linux-mm@kvack.org Cc: gorcunov@openvz.org Cc: xemul@virtuozzo.com Link: http://lkml.kernel.org/r/20160905133308.28234-2-dsafonov@virtuozzo.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-08-06Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds1-20/+5
Pull more KVM updates from Paolo Bonzini: - ARM bugfix and MSI injection support - x86 nested virt tweak and OOPS fix - Simplify pvclock code (vdso bits acked by Andy Lutomirski). * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: nvmx: mark ept single context invalidation as supported nvmx: remove comment about missing nested vpid support KVM: lapic: fix access preemption timer stuff even if kernel_irqchip=off KVM: documentation: fix KVM_CAP_X2APIC_API information x86: vdso: use __pvclock_read_cycles pvclock: introduce seqcount-like API arm64: KVM: Set cpsr before spsr on fault injection KVM: arm: vgic-irqfd: Workaround changing kvm_set_routing_entry prototype KVM: arm/arm64: Enable MSI routing KVM: arm/arm64: Enable irqchip routing KVM: Move kvm_setup_default/empty_irq_routing declaration in arch specific header KVM: irqchip: Convey devid to kvm_set_msi KVM: Add devid in kvm_kernel_irq_routing_entry KVM: api: Pass the devid in the msi routing entry
2016-08-06Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds1-0/+6
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar: "Two fixes and a cleanup-fix, to the syscall entry code and to ptrace" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/syscalls/64: Add compat_sys_keyctl for 32-bit userspace x86/ptrace: Stop setting TS_COMPAT in ptrace code x86/vdso: Error out if the vDSO isn't a valid DSO
2016-08-04x86: vdso: use __pvclock_read_cyclesPaolo Bonzini1-13/+3
The new simplified __pvclock_read_cycles does the same computation as vread_pvclock, except that (because it takes the pvclock_vcpu_time_info pointer) it has to be moved inside the loop. Since the loop is expected to never roll, this makes no difference. Acked-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-08-04pvclock: introduce seqcount-like APIPaolo Bonzini1-7/+2
The version field in struct pvclock_vcpu_time_info basically implements a seqcount. Wrap it with the usual read_begin and read_retry functions, and use these APIs instead of peppering the code with smp_rmb()s. While at it, change it to the more pedantically correct virt_rmb(). With this change, __pvclock_read_cycles can be simplified noticeably. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-08-02Merge branch 'kbuild' of ↵Linus Torvalds1-1/+2
git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild Pull kbuild updates from Michal Marek: - GCC plugin support by Emese Revfy from grsecurity, with a fixup from Kees Cook. The plugins are meant to be used for static analysis of the kernel code. Two plugins are provided already. - reduction of the gcc commandline by Arnd Bergmann. - IS_ENABLED / IS_REACHABLE macro enhancements by Masahiro Yamada - bin2c fix by Michael Tautschnig - setlocalversion fix by Wolfram Sang * 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild: gcc-plugins: disable under COMPILE_TEST kbuild: Abort build on bad stack protector flag scripts: Fix size mismatch of kexec_purgatory_size kbuild: make samples depend on headers_install Kbuild: don't add obj tree in additional includes Kbuild: arch: look for generated headers in obtree Kbuild: always prefix objtree in LINUXINCLUDE Kbuild: avoid duplicate include path Kbuild: don't add ../../ to include path vmlinux.lds.h: replace config_enabled() with IS_ENABLED() kconfig.h: allow to use IS_{ENABLE,REACHABLE} in macro expansion kconfig.h: use already defined macros for IS_REACHABLE() define export.h: use __is_defined() to check if __KSYM_* is defined kconfig.h: use __is_defined() to check if MODULE is defined kbuild: setlocalversion: print error to STDERR Add sancov plugin Add Cyclomatic complexity GCC plugin GCC plugin infrastructure Shared library support
2016-08-01Merge branch 'x86/asm' into x86/urgent, to pick up fixIngo Molnar1-0/+6
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-29Merge branch 'smp-hotplug-for-linus' of ↵Linus Torvalds1-16/+4
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull smp hotplug updates from Thomas Gleixner: "This is the next part of the hotplug rework. - Convert all notifiers with a priority assigned - Convert all CPU_STARTING/DYING notifiers The final removal of the STARTING/DYING infrastructure will happen when the merge window closes. Another 700 hundred line of unpenetrable maze gone :)" * 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (70 commits) timers/core: Correct callback order during CPU hot plug leds/trigger/cpu: Move from CPU_STARTING to ONLINE level powerpc/numa: Convert to hotplug state machine arm/perf: Fix hotplug state machine conversion irqchip/armada: Avoid unused function warnings ARC/time: Convert to hotplug state machine clocksource/atlas7: Convert to hotplug state machine clocksource/armada-370-xp: Convert to hotplug state machine clocksource/exynos_mct: Convert to hotplug state machine clocksource/arm_global_timer: Convert to hotplug state machine rcu: Convert rcutree to hotplug state machine KVM/arm/arm64/vgic-new: Convert to hotplug state machine smp/cfd: Convert core to hotplug state machine x86/x2apic: Convert to CPU hotplug state machine profile: Convert to hotplug state machine timers/core: Convert to hotplug state machine hrtimer: Convert to hotplug state machine x86/tboot: Convert to hotplug state machine arm64/armv8 deprecated: Convert to hotplug state machine hwtracing/coresight-etm4x: Convert to hotplug state machine ...
2016-07-26Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Ingo Molnar: "This tree contains tooling fixes plus some additions: - fixes to the vdso2c build environment that Stephen Rothwell is using for the linux-next build (Arnaldo Carvalho de Melo) - AVX-512 instruction mappings (Adrian Hunter) - misc fixes" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: Revert "perf tools: event.h needs asm/perf_regs.h" x86: Make the vdso2c compiler use the host architecture headers tools build: Fix objtool build with ARCH=x86_64 objtool: Always use host headers objtool: Use tools/scripts/Makefile.arch to get ARCH and HOSTARCH tools build: Add HOSTARCH Makefile variable perf tests kmod-path: Fix build on ubuntu:16.04-x-armhf perf tools: Add AVX-512 instructions to the new instructions test perf tools: Add AVX-512 support to the instruction decoder used by Intel PT x86/insn: Add AVX-512 support to the instruction decoder x86/insn: perf tools: Fix vcvtph2ps instruction decoding
2016-07-25x86: Make the vdso2c compiler use the host architecture headersStephen Rothwell1-1/+1
To be clear: this is a ppc64le hosted, x86_64 target cross build. Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160723150845.3af8e452@canb.auug.org.au Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-07-19x86/vdso: Error out if the vDSO isn't a valid DSOAndy Lutomirski1-0/+6
Some distros has been playing with toolchain changes that can affect the type of ELF objects built. Occasionally, this goes wrong and the vDSO ends up not being a DSO at all. This causes the kernel to end up broken in a surprisingly subtle way -- glibc apparently silently ignores a vDSO that isn't a DSO, so everything works, albeit slowly, until users try a different libc implementation. Make the kernel build process a bit more robust: fail outright if the vDSO isn't ET_DYN or is missing its PT_DYNAMIC segment. I've never seen this in an unmodified kernel. See: https://github.com/docker/docker/issues/23378 Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/8a30e0a07c3b47ff917a8daa2df5e407cc0c6698.1468878336.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-15Merge branch 'x86/asm' into x86/mm, to resolve conflictsIngo Molnar3-16/+4
Conflicts: tools/testing/selftests/x86/Makefile Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-14x86/vdso: Convert to hotplug state machineSebastian Andrzej Siewior1-16/+4
Install the callbacks via the state machine and let the core invoke the callbacks on the already online CPUs. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de> Acked-by: Andy Lutomirski <luto@amacapital.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: rt@linutronix.de Link: http://lkml.kernel.org/r/20160713153332.987560239@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-08x86/vdso: Add mremap hook to vm_special_mappingDmitry Safonov1-5/+42
Add possibility for 32-bit user-space applications to move the vDSO mapping. Previously, when a user-space app called mremap() for the vDSO address, in the syscall return path it would land on the previous address of the vDSOpage, resulting in segmentation violation. Now it lands fine and returns to userspace with a remapped vDSO. This will also fix the context.vdso pointer for 64-bit, which does not affect the user of vDSO after mremap() currently, but this may change in the future. As suggested by Andy, return -EINVAL for mremap() that would split the vDSO image: that operation cannot possibly result in a working system so reject it. Renamed and moved the text_mapping structure declaration inside map_vdso(), as it used only there and now it complements the vvar_mapping variable. There is still a problem for remapping the vDSO in glibc applications: the linker relocates addresses for syscalls on the vDSO page, so you need to relink with the new addresses. Without that the next syscall through glibc may fail: Program received signal SIGSEGV, Segmentation fault. #0 0xf7fd9b80 in __kernel_vsyscall () #1 0xf7ec8238 in _exit () from /usr/lib32/libc.so.6 Signed-off-by: Dmitry Safonov <dsafonov@virtuozzo.com> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: 0x7f454c46@gmail.com Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-mm@kvack.org Link: http://lkml.kernel.org/r/20160628113539.13606-2-dsafonov@virtuozzo.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-14x86/vdso/32: Assemble sigreturn.S separatelyAndy Lutomirski3-16/+4
sigreturn.S was historically included by the various __kernel_vsyscall implementations due to assumptions about all the 32-bit vDSO images having the sigreturn symbols at the same address. Those assumptions were removed in v3.16, and as of v4.4, there is only a single 32-bit vDSO left. Simplify the build process by assembling sigreturn.S into a normal object file. Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/d7b6dfde3c7397aa26977320da90448363b5a7e9.1465505753.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-07GCC plugin infrastructureEmese Revfy1-1/+2
This patch allows to build the whole kernel with GCC plugins. It was ported from grsecurity/PaX. The infrastructure supports building out-of-tree modules and building in a separate directory. Cross-compilation is supported too. Currently the x86, arm, arm64 and uml architectures enable plugins. The directory of the gcc plugins is scripts/gcc-plugins. You can use a file or a directory there. The plugins compile with these options: * -fno-rtti: gcc is compiled with this option so the plugins must use it too * -fno-exceptions: this is inherited from gcc too * -fasynchronous-unwind-tables: this is inherited from gcc too * -ggdb: it is useful for debugging a plugin (better backtrace on internal errors) * -Wno-narrowing: to suppress warnings from gcc headers (ipa-utils.h) * -Wno-unused-variable: to suppress warnings from gcc headers (gcc_version variable, plugin-version.h) The infrastructure introduces a new Makefile target called gcc-plugins. It supports all gcc versions from 4.5 to 6.0. The scripts/gcc-plugin.sh script chooses the proper host compiler (gcc-4.7 can be built by either gcc or g++). This script also checks the availability of the included headers in scripts/gcc-plugins/gcc-common.h. The gcc-common.h header contains frequently included headers for GCC plugins and it has a compatibility layer for the supported gcc versions. The gcc-generate-*-pass.h headers automatically generate the registration structures for GIMPLE, SIMPLE_IPA, IPA and RTL passes. Note that 'make clean' keeps the *.so files (only the distclean or mrproper targets clean all) because they are needed for out-of-tree modules. Based on work created by the PaX Team. Signed-off-by: Emese Revfy <re.emese@gmail.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Michal Marek <mmarek@suse.com>
2016-05-26Merge branch 'kbuild' of ↵Linus Torvalds1-2/+2
git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild Pull kbuild updates from Michal Marek: - new option CONFIG_TRIM_UNUSED_KSYMS which does a two-pass build and unexports symbols which are not used in the current config [Nicolas Pitre] - several kbuild rule cleanups [Masahiro Yamada] - warning option adjustments for gcov etc [Arnd Bergmann] - a few more small fixes * 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild: (31 commits) kbuild: move -Wunused-const-variable to W=1 warning level kbuild: fix if_change and friends to consider argument order kbuild: fix adjust_autoksyms.sh for modules that need only one symbol kbuild: fix ksym_dep_filter when multiple EXPORT_SYMBOL() on the same line gcov: disable -Wmaybe-uninitialized warning gcov: disable tree-loop-im to reduce stack usage gcov: disable for COMPILE_TEST Kbuild: disable 'maybe-uninitialized' warning for CONFIG_PROFILE_ALL_BRANCHES Kbuild: change CC_OPTIMIZE_FOR_SIZE definition kbuild: forbid kernel directory to contain spaces and colons kbuild: adjust ksym_dep_filter for some cmd_* renames kbuild: Fix dependencies for final vmlinux link kbuild: better abstract vmlinux sequential prerequisites kbuild: fix call to adjust_autoksyms.sh when output directory specified kbuild: Get rid of KBUILD_STR kbuild: rename cmd_as_s_S to cmd_cpp_s_S kbuild: rename cmd_cc_i_c to cmd_cpp_i_c kbuild: drop redundant "PHONY += FORCE" kbuild: delete unnecessary "@:" kbuild: mark help target as PHONY ...
2016-05-23vdso: make arch_setup_additional_pages wait for mmap_sem for write killableMichal Hocko1-1/+2
most architectures are relying on mmap_sem for write in their arch_setup_additional_pages. If the waiting task gets killed by the oom killer it would block oom_reaper from asynchronous address space reclaim and reduce the chances of timely OOM resolving. Wait for the lock in the killable mode and return with EINTR if the task got killed while waiting. Signed-off-by: Michal Hocko <mhocko@suse.com> Acked-by: Andy Lutomirski <luto@amacapital.net> [x86 vdso] Acked-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-20kbuild: drop FORCE from PHONY targetsMasahiro Yamada1-2/+2
These targets are marked as PHONY. No need to add FORCE to their dependency. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Michal Marek <mmarek@suse.com>
2016-04-13x86/vdso: Remove direct HPET access through the vDSOAndy Lutomirski3-29/+2
Allowing user code to map the HPET is problematic. HPET implementations are notoriously buggy, and there are probably many machines on which even MMIO reads from bogus HPET addresses are problematic. We have a report that the Dell Precision M2800 with: ACPI: HPET 0x00000000C8FE6238 000038 (v01 DELL CBX3 01072009 AMI. 00000005) is either so slow when accessing the HPET or actually hangs in some regard, causing soft lockups to be reported if users do unexpected things to the HPET. The vclock HPET code has also always been a questionable speedup. Accessing an HPET is exceedingly slow (on the order of several microseconds), so the added overhead in requiring a syscall to read the HPET is a small fraction of the total code of accessing it. To avoid future problems, let's just delete the code entirely. In the long run, this could actually be a speedup. Waiman Long as a patch to optimize the case where multiple CPUs contend for the HPET, but that won't help unless all the accesses are mediated by the kernel. Reported-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Borislav Petkov <bp@alien8.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Waiman Long <Waiman.Long@hpe.com> Cc: Waiman Long <waiman.long@hpe.com> Link: http://lkml.kernel.org/r/d2f90bba98db9905041cff294646d290d378f67a.1460074438.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-24Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar: "Misc fixes: - fix hotplug bugs - fix irq live lock - fix various topology handling bugs - fix APIC ACK ordering - fix PV iopl handling - fix speling - fix/tweak memcpy_mcsafe() return value - fix fbcon bug - remove stray prototypes" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/msr: Remove unused native_read_tscp() x86/apic: Remove declaration of unused hw_nmi_is_cpu_stuck x86/oprofile/nmi: Add missing hotplug FROZEN handling x86/hpet: Use proper mask to modify hotplug action x86/apic/uv: Fix the hotplug notifier x86/apb/timer: Use proper mask to modify hotplug action x86/topology: Use total_cpus not nr_cpu_ids for logical packages x86/topology: Fix Intel HT disable x86/topology: Fix logical package mapping x86/irq: Cure live lock in fixup_irqs() x86/tsc: Prevent NULL pointer deref in calibrate_delay_is_known() x86/apic: Fix suspicious RCU usage in smp_trace_call_function_interrupt() x86/iopl: Fix iopl capability check on Xen PV x86/iopl/64: Properly context-switch IOPL on Xen PV selftests/x86: Add an iopl test x86/mm, x86/mce: Fix return type/value for memcpy_mcsafe() x86/video: Don't assume all FB devices are PCI devices arch/x86/irq: Purge useless handler declarations from hw_irq.h x86: Fix misspellings in comments
2016-03-22kernel: add kcov code coverageDmitry Vyukov1-0/+3
kcov provides code coverage collection for coverage-guided fuzzing (randomized testing). Coverage-guided fuzzing is a testing technique that uses coverage feedback to determine new interesting inputs to a system. A notable user-space example is AFL (http://lcamtuf.coredump.cx/afl/). However, this technique is not widely used for kernel testing due to missing compiler and kernel support. kcov does not aim to collect as much coverage as possible. It aims to collect more or less stable coverage that is function of syscall inputs. To achieve this goal it does not collect coverage in soft/hard interrupts and instrumentation of some inherently non-deterministic or non-interesting parts of kernel is disbled (e.g. scheduler, locking). Currently there is a single coverage collection mode (tracing), but the API anticipates additional collection modes. Initially I also implemented a second mode which exposes coverage in a fixed-size hash table of counters (what Quentin used in his original patch). I've dropped the second mode for simplicity. This patch adds the necessary support on kernel side. The complimentary compiler support was added in gcc revision 231296. We've used this support to build syzkaller system call fuzzer, which has found 90 kernel bugs in just 2 months: https://github.com/google/syzkaller/wiki/Found-Bugs We've also found 30+ bugs in our internal systems with syzkaller. Another (yet unexplored) direction where kcov coverage would greatly help is more traditional "blob mutation". For example, mounting a random blob as a filesystem, or receiving a random blob over wire. Why not gcov. Typical fuzzing loop looks as follows: (1) reset coverage, (2) execute a bit of code, (3) collect coverage, repeat. A typical coverage can be just a dozen of basic blocks (e.g. an invalid input). In such context gcov becomes prohibitively expensive as reset/collect coverage steps depend on total number of basic blocks/edges in program (in case of kernel it is about 2M). Cost of kcov depends only on number of executed basic blocks/edges. On top of that, kernel requires per-thread coverage because there are always background threads and unrelated processes that also produce coverage. With inlined gcov instrumentation per-thread coverage is not possible. kcov exposes kernel PCs and control flow to user-space which is insecure. But debugfs should not be mapped as user accessible. Based on a patch by Quentin Casasnovas. [akpm@linux-foundation.org: make task_struct.kcov_mode have type `enum kcov_mode'] [akpm@linux-foundation.org: unbreak allmodconfig] [akpm@linux-foundation.org: follow x86 Makefile layout standards] Signed-off-by: Dmitry Vyukov <dvyukov@google.com> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: syzkaller <syzkaller@googlegroups.com> Cc: Vegard Nossum <vegard.nossum@oracle.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Tavis Ormandy <taviso@google.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com> Cc: Kostya Serebryany <kcc@google.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Kees Cook <keescook@google.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: David Drysdale <drysdale@google.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-20Merge branch 'core-objtool-for-linus' of ↵Linus Torvalds1-2/+4
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull 'objtool' stack frame validation from Ingo Molnar: "This tree adds a new kernel build-time object file validation feature (ONFIG_STACK_VALIDATION=y): kernel stack frame correctness validation. It was written by and is maintained by Josh Poimboeuf. The motivation: there's a category of hard to find kernel bugs, most of them in assembly code (but also occasionally in C code), that degrades the quality of kernel stack dumps/backtraces. These bugs are hard to detect at the source code level. Such bugs result in incorrect/incomplete backtraces most of time - but can also in some rare cases result in crashes or other undefined behavior. The build time correctness checking is done via the new 'objtool' user-space utility that was written for this purpose and which is hosted in the kernel repository in tools/objtool/. The tool's (very simple) UI and source code design is shaped after Git and perf and shares quite a bit of infrastructure with tools/perf (which tooling infrastructure sharing effort got merged via perf and is already upstream). Objtool follows the well-known kernel coding style. Objtool does not try to check .c or .S files, it instead analyzes the resulting .o generated machine code from first principles: it decodes the instruction stream and interprets it. (Right now objtool supports the x86-64 architecture.) From tools/objtool/Documentation/stack-validation.txt: "The kernel CONFIG_STACK_VALIDATION option enables a host tool named objtool which runs at compile time. It has a "check" subcommand which analyzes every .o file and ensures the validity of its stack metadata. It enforces a set of rules on asm code and C inline assembly code so that stack traces can be reliable. Currently it only checks frame pointer usage, but there are plans to add CFI validation for C files and CFI generation for asm files. For each function, it recursively follows all possible code paths and validates the correct frame pointer state at each instruction. It also follows code paths involving special sections, like .altinstructions, __jump_table, and __ex_table, which can add alternative execution paths to a given instruction (or set of instructions). Similarly, it knows how to follow switch statements, for which gcc sometimes uses jump tables." When this new kernel option is enabled (it's disabled by default), the tool, if it finds any suspicious assembly code pattern, outputs warnings in compiler warning format: warning: objtool: rtlwifi_rate_mapping()+0x2e7: frame pointer state mismatch warning: objtool: cik_tiling_mode_table_init()+0x6ce: call without frame pointer save/setup warning: objtool:__schedule()+0x3c0: duplicate frame pointer save warning: objtool:__schedule()+0x3fd: sibling call from callable instruction with changed frame pointer ... so that scripts that pick up compiler warnings will notice them. All known warnings triggered by the tool are fixed by the tree, most of the commits in fact prepare the kernel to be warning-free. Most of them are bugfixes or cleanups that stand on their own, but there are also some annotations of 'special' stack frames for justified cases such entries to JIT-ed code (BPF) or really special boot time code. There are two other long-term motivations behind this tool as well: - To improve the quality and reliability of kernel stack frames, so that they can be used for optimized live patching. - To create independent infrastructure to check the correctness of CFI stack frames at build time. CFI debuginfo is notoriously unreliable and we cannot use it in the kernel as-is without extra checking done both on the kernel side and on the build side. The quality of kernel stack frames matters to debuggability as well, so IMO we can merge this without having to consider the live patching or CFI debuginfo angle" * 'core-objtool-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (52 commits) objtool: Only print one warning per function objtool: Add several performance improvements tools: Copy hashtable.h into tools directory objtool: Fix false positive warnings for functions with multiple switch statements objtool: Rename some variables and functions objtool: Remove superflous INIT_LIST_HEAD objtool: Add helper macros for traversing instructions objtool: Fix false positive warnings related to sibling calls objtool: Compile with debugging symbols objtool: Detect infinite recursion objtool: Prevent infinite recursion in noreturn detection objtool: Detect and warn if libelf is missing and don't break the build tools: Support relative directory path for 'O=' objtool: Support CROSS_COMPILE x86/asm/decoder: Use explicitly signed chars objtool: Enable stack metadata validation on 64-bit x86 objtool: Add CONFIG_STACK_VALIDATION option objtool: Add tool to perform compile-time stack metadata validation x86/kprobes: Mark kretprobe_trampoline() stack frame as non-standard sched: Always inline context_switch() ...
2016-03-17Merge branch 'x86/cleanups' into x86/urgentIngo Molnar1-1/+1
Pull in some merge window leftovers. Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-15Merge branch 'x86-asm-for-linus' of ↵Linus Torvalds4-57/+80
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 asm updates from Ingo Molnar: "This is another big update. Main changes are: - lots of x86 system call (and other traps/exceptions) entry code enhancements. In particular the complex parts of the 64-bit entry code have been migrated to C code as well, and a number of dusty corners have been refreshed. (Andy Lutomirski) - vDSO special mapping robustification and general cleanups (Andy Lutomirski) - cpufeature refactoring, cleanups and speedups (Borislav Petkov) - lots of other changes ..." * 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (64 commits) x86/cpufeature: Enable new AVX-512 features x86/entry/traps: Show unhandled signal for i386 in do_trap() x86/entry: Call enter_from_user_mode() with IRQs off x86/entry/32: Change INT80 to be an interrupt gate x86/entry: Improve system call entry comments x86/entry: Remove TIF_SINGLESTEP entry work x86/entry/32: Add and check a stack canary for the SYSENTER stack x86/entry/32: Simplify and fix up the SYSENTER stack #DB/NMI fixup x86/entry: Only allocate space for tss_struct::SYSENTER_stack if needed x86/entry: Vastly simplify SYSENTER TF (single-step) handling x86/entry/traps: Clear DR6 early in do_debug() and improve the comment x86/entry/traps: Clear TIF_BLOCKSTEP on all debug exceptions x86/entry/32: Restore FLAGS on SYSEXIT x86/entry/32: Filter NT and speed up AC filtering in SYSENTER x86/entry/compat: In SYSENTER, sink AC clearing below the existing FLAGS test selftests/x86: In syscall_nt, test NT|TF as well x86/asm-offsets: Remove PARAVIRT_enabled x86/entry/32: Introduce and use X86_BUG_ESPFIX instead of paravirt_enabled uprobes: __create_xol_area() must nullify xol_mapping.fault x86/cpufeature: Create a new synthetic cpu capability for machine check recovery ...
2016-02-29objtool: Mark non-standard object files and directoriesJosh Poimboeuf1-2/+4
Code which runs outside the kernel's normal mode of operation often does unusual things which can cause a static analysis tool like objtool to emit false positive warnings: - boot image - vdso image - relocation - realmode - efi - head - purgatory - modpost Set OBJECT_FILES_NON_STANDARD for their related files and directories, which will tell objtool to skip checking them. It's ok to skip them because they don't affect runtime stack traces. Also skip the following code which does the right thing with respect to frame pointers, but is too "special" to be validated by a tool: - entry - mcount Also skip the test_nx module because it modifies its exception handling table at runtime, which objtool can't understand. Fortunately it's just a test module so it doesn't matter much. Currently objtool is the only user of OBJECT_FILES_NON_STANDARD, but it might eventually be useful for other tools. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at> Cc: Borislav Petkov <bp@alien8.de> Cc: Chris J Arges <chris.j.arges@canonical.com> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michal Marek <mmarek@suse.cz> Cc: Namhyung Kim <namhyung@gmail.com> Cc: Pedro Alves <palves@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: live-patching@vger.kernel.org Link: http://lkml.kernel.org/r/366c080e3844e8a5b6a0327dc7e8c2b90ca3baeb.1456719558.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-24x86: Fix misspellings in commentsAdam Buchbinder1-1/+1
Signed-off-by: Adam Buchbinder <adam.buchbinder@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: trivial@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-22x86/vdso: Mark the vDSO code read-only after initKees Cook1-1/+1
The vDSO does not need to be writable after __init, so mark it as __ro_after_init. The result kills the exploit method of writing to the vDSO from kernel space resulting in userspace executing the modified code, as shown here to bypass SMEP restrictions: http://itszn.com/blog/?p=21 The memory map (with added vDSO address reporting) shows the vDSO moving into read-only memory: Before: [ 0.143067] vDSO @ ffffffff82004000 [ 0.143551] vDSO @ ffffffff82006000 ---[ High Kernel Mapping ]--- 0xffffffff80000000-0xffffffff81000000 16M pmd 0xffffffff81000000-0xffffffff81800000 8M ro PSE GLB x pmd 0xffffffff81800000-0xffffffff819f3000 1996K ro GLB x pte 0xffffffff819f3000-0xffffffff81a00000 52K ro NX pte 0xffffffff81a00000-0xffffffff81e00000 4M ro PSE GLB NX pmd 0xffffffff81e00000-0xffffffff81e05000 20K ro GLB NX pte 0xffffffff81e05000-0xffffffff82000000 2028K ro NX pte 0xffffffff82000000-0xffffffff8214f000 1340K RW GLB NX pte 0xffffffff8214f000-0xffffffff82281000 1224K RW NX pte 0xffffffff82281000-0xffffffff82400000 1532K RW GLB NX pte 0xffffffff82400000-0xffffffff83200000 14M RW PSE GLB NX pmd 0xffffffff83200000-0xffffffffc0000000 974M pmd After: [ 0.145062] vDSO @ ffffffff81da1000 [ 0.146057] vDSO @ ffffffff81da4000 ---[ High Kernel Mapping ]--- 0xffffffff80000000-0xffffffff81000000 16M pmd 0xffffffff81000000-0xffffffff81800000 8M ro PSE GLB x pmd 0xffffffff81800000-0xffffffff819f3000 1996K ro GLB x pte 0xffffffff819f3000-0xffffffff81a00000 52K ro NX pte 0xffffffff81a00000-0xffffffff81e00000 4M ro PSE GLB NX pmd 0xffffffff81e00000-0xffffffff81e0b000 44K ro GLB NX pte 0xffffffff81e0b000-0xffffffff82000000 2004K ro NX pte 0xffffffff82000000-0xffffffff8214c000 1328K RW GLB NX pte 0xffffffff8214c000-0xffffffff8227e000 1224K RW NX pte 0xffffffff8227e000-0xffffffff82400000 1544K RW GLB NX pte 0xffffffff82400000-0xffffffff83200000 14M RW PSE GLB NX pmd 0xffffffff83200000-0xffffffffc0000000 974M pmd Based on work by PaX Team and Brad Spengler. Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Andy Lutomirski <luto@kernel.org> Acked-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brad Spengler <spender@grsecurity.net> Cc: Brian Gerst <brgerst@gmail.com> Cc: David Brown <david.brown@linaro.org> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Emese Revfy <re.emese@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mathias Krause <minipli@googlemail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: PaX Team <pageexec@freemail.hu> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: kernel-hardening@lists.openwall.com Cc: linux-arch <linux-arch@vger.kernel.org> Link: http://lkml.kernel.org/r/1455748879-21872-7-git-send-email-keescook@chromium.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-01-30x86/vdso: Use static_cpu_has()Borislav Petkov1-1/+1
... and simplify and speed up a tad. Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1453842730-28463-10-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-01-30x86/cpufeature: Carve out X86_FEATURE_*Borislav Petkov3-2/+2
Move them to a separate header and have the following dependency: x86/cpufeatures.h <- x86/processor.h <- x86/cpufeature.h This makes it easier to use the header in asm code and not include the whole cpufeature.h and add guards for asm. Suggested-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1453842730-28463-5-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-01-29Merge tag 'v4.5-rc1' into x86/asm, to refresh the branch before merging new ↵Ingo Molnar2-6/+7
changes Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-01-20UBSAN: run-time undefined behavior sanity checkerAndrey Ryabinin1-0/+1
UBSAN uses compile-time instrumentation to catch undefined behavior (UB). Compiler inserts code that perform certain kinds of checks before operations that could cause UB. If check fails (i.e. UB detected) __ubsan_handle_* function called to print error message. So the most of the work is done by compiler. This patch just implements ubsan handlers printing errors. GCC has this capability since 4.9.x [1] (see -fsanitize=undefined option and its suboptions). However GCC 5.x has more checkers implemented [2]. Article [3] has a bit more details about UBSAN in the GCC. [1] - https://gcc.gnu.org/onlinedocs/gcc-4.9.0/gcc/Debugging-Options.html [2] - https://gcc.gnu.org/onlinedocs/gcc/Debugging-Options.html [3] - http://developerblog.redhat.com/2014/10/16/gcc-undefined-behavior-sanitizer-ubsan/ Issues which UBSAN has found thus far are: Found bugs: * out-of-bounds access - 97840cb67ff5 ("netfilter: nfnetlink: fix insufficient validation in nfnetlink_bind") undefined shifts: * d48458d4a768 ("jbd2: use a better hash function for the revoke table") * 10632008b9e1 ("clockevents: Prevent shift out of bounds") * 'x << -1' shift in ext4 - http://lkml.kernel.org/r/<5444EF21.8020501@samsung.com> * undefined rol32(0) - http://lkml.kernel.org/r/<1449198241-20654-1-git-send-email-sasha.levin@oracle.com> * undefined dirty_ratelimit calculation - http://lkml.kernel.org/r/<566594E2.3050306@odin.com> * undefined roundown_pow_of_two(0) - http://lkml.kernel.org/r/<1449156616-11474-1-git-send-email-sasha.levin@oracle.com> * [WONTFIX] undefined shift in __bpf_prog_run - http://lkml.kernel.org/r/<CACT4Y+ZxoR3UjLgcNdUm4fECLMx2VdtfrENMtRRCdgHB2n0bJA@mail.gmail.com> WONTFIX here because it should be fixed in bpf program, not in kernel. signed overflows: * 32a8df4e0b33f ("sched: Fix odd values in effective_load() calculations") * mul overflow in ntp - http://lkml.kernel.org/r/<1449175608-1146-1-git-send-email-sasha.levin@oracle.com> * incorrect conversion into rtc_time in rtc_time64_to_tm() - http://lkml.kernel.org/r/<1449187944-11730-1-git-send-email-sasha.levin@oracle.com> * unvalidated timespec in io_getevents() - http://lkml.kernel.org/r/<CACT4Y+bBxVYLQ6LtOKrKtnLthqLHcw-BMp3aqP3mjdAvr9FULQ@mail.gmail.com> * [NOTABUG] signed overflow in ktime_add_safe() - http://lkml.kernel.org/r/<CACT4Y+aJ4muRnWxsUe1CMnA6P8nooO33kwG-c8YZg=0Xc8rJqw@mail.gmail.com> [akpm@linux-foundation.org: fix unused local warning] [akpm@linux-foundation.org: fix __int128 build woes] Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Michal Marek <mmarek@suse.cz> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Yury Gribov <y.gribov@samsung.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Konstantin Khlebnikov <koct9i@gmail.com> Cc: Kostya Serebryany <kcc@google.com> Cc: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-13x86/vdso/pvclock: Protect STABLE check with the seqcountAndy Lutomirski1-6/+6
If the clock becomes unstable while we're reading it, we need to bail. We can do this by simply moving the check into the seqcount loop. Reported-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: Alexander Graf <agraf@suse.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Radim Krcmar <rkrcmar@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/755dcedb17269e1d7ce12a9a713dea303835137e.1451949191.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-01-12x86/vdso: Disallow vvar access to vclock IO for never-used vclocksAndy Lutomirski1-2/+2
It makes me uncomfortable that even modern systems grant every process direct read access to the HPET. While fixing this for real without regressing anything is a mess (unmapping the HPET is tricky because we don't adequately track all the mappings), we can do almost as well by tracking which vclocks have ever been used and only allowing pages associated with used vclocks to be faulted in. This will cause rogue programs that try to peek at the HPET to get SIGBUS instead on most systems. We can't restrict faults to vclock pages that are associated with the currently selected vclock due to a race: a process could start to access the HPET for the first time and race against a switch away from the HPET as the current clocksource. We can't segfault the process trying to peek at the HPET in this case, even though the process isn't going to do anything useful with the data. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/e79d06295625c02512277737ab55085a498ac5d8.1451446564.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-01-12x86/vdso: Use ->fault() instead of remap_pfn_range() for the vvar mappingAndy Lutomirski1-40/+57
This is IMO much less ugly, and it also opens the door to disallowing unprivileged userspace HPET access on systems with usable TSCs. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/c19c2909e5ee3c3d8742f916586676bb7c40345f.1451446564.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-01-12x86/vdso: Use .fault for the vDSO text mappingAndy Lutomirski2-14/+19
The old scheme for mapping the vDSO text is rather complicated. vdso2c generates a struct vm_special_mapping and a blank .pages array of the correct size for each vdso image. Init code in vdso/vma.c populates the .pages array for each vDSO image, and the mapping code selects the appropriate struct vm_special_mapping. With .fault, we can use a less roundabout approach: vdso_fault() just returns the appropriate page for the selected vDSO image. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/f886954c186bafd74e1b967c8931d852ae199aa2.1451446564.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-01-12x86/vdso: Track each mm's loaded vDSO image as well as its baseAndy Lutomirski1-0/+1
As we start to do more intelligent things with the vDSO at runtime (as opposed to just at mm initialization time), we'll need to know which vDSO is in use. In principle, we could guess based on the mm type, but that's over-complicated and error-prone. Instead, just track it in the mmu context. Signed-off-by: Andy Lutomirski <luto@kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/c99ac48681bad709ca7ad5ee899d9042a3af6b00.1451446564.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-01-11Merge branch 'x86-asm-for-linus' of ↵Linus Torvalds4-79/+92
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 asm updates from Ingo Molnar: "The main changes in this cycle were: - vDSO and asm entry improvements (Andy Lutomirski) - Xen paravirt entry enhancements (Boris Ostrovsky) - asm entry labels enhancement (Borislav Petkov) - and other misc changes (Thomas Gleixner, me)" * 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/vsdo: Fix build on PARAVIRT_CLOCK=y, KVM_GUEST=n Revert "x86/kvm: On KVM re-enable (e.g. after suspend), update clocks" x86/entry/64_compat: Make labels local x86/platform/uv: Include clocksource.h for clocksource_touch_watchdog() x86/vdso: Enable vdso pvclock access on all vdso variants x86/vdso: Remove pvclock fixmap machinery x86/vdso: Get pvclock data from the vvar VMA instead of the fixmap x86, vdso, pvclock: Simplify and speed up the vdso pvclock reader x86/kvm: On KVM re-enable (e.g. after suspend), update clocks x86/entry/64: Bypass enter_from_user_mode on non-context-tracking boots x86/asm: Add asm macros for static keys/jump labels x86/asm: Error out if asm/jump_label.h is included inappropriately context_tracking: Switch to new static_branch API x86/entry, x86/paravirt: Remove the unused usergs_sysret32 PV op x86/paravirt: Remove the unused irq_enable_sysexit pv op x86/xen: Avoid fast syscall path for Xen PV guests