mirror of https://github.com/torvalds/linux.git
9063c61fd5
The discussion about using "access_ok()" in get_user_pages_fast() (see commit 7f8189068726492950bf1a2dcfd9b51314560abf: "x86: don't use 'access_ok()' as a range check in get_user_pages_fast()" for details and end result), made us notice that x86-64 was really being very sloppy about virtual address checking. So be way more careful and straightforward about masking x86-64 virtual addresses: - All the VIRTUAL_MASK* variants now cover half of the address space, it's not like we can use the full mask on a signed integer, and the larger mask just invites mistakes when applying it to either half of the 48-bit address space. - /proc/kcore's kc_offset_to_vaddr() becomes a lot more obvious when it transforms a file offset into a (kernel-half) virtual address. - Unify/simplify the 32-bit and 64-bit USER_DS definition to be based on TASK_SIZE_MAX. This cleanup and more careful/obvious user virtual address checking also uncovered a buglet in the x86-64 implementation of strnlen_user(): it would do an "access_ok()" check on the whole potential area, even if the string itself was much shorter, and thus return an error even for valid strings. Our sloppy checking had hidden this. So this fixes 'strnlen_user()' to do this properly, the same way we already handled user strings in 'strncpy_from_user()'. Namely by just checking the first byte, and then relying on fault handling for the rest. That always works, since we impose a guard page that cannot be mapped at the end of the user space address space (and even if we didn't, we'd have the address space hole). Acked-by: Ingo Molnar <mingo@elte.hu> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Nick Piggin <npiggin@suse.de> Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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| .. | ||
| uv | ||
| visws | ||
| xen | ||
| Kbuild | ||
| a.out-core.h | ||
| a.out.h | ||
| acpi.h | ||
| aes.h | ||
| agp.h | ||
| alternative-asm.h | ||
| alternative.h | ||
| amd_iommu.h | ||
| amd_iommu_types.h | ||
| apic.h | ||
| apicdef.h | ||
| apicnum.h | ||
| apm.h | ||
| asm.h | ||
| atomic.h | ||
| atomic_32.h | ||
| atomic_64.h | ||
| auxvec.h | ||
| bios_ebda.h | ||
| bitops.h | ||
| bitsperlong.h | ||
| boot.h | ||
| bootparam.h | ||
| bug.h | ||
| bugs.h | ||
| byteorder.h | ||
| cache.h | ||
| cacheflush.h | ||
| calgary.h | ||
| calling.h | ||
| checksum.h | ||
| checksum_32.h | ||
| checksum_64.h | ||
| cmpxchg.h | ||
| cmpxchg_32.h | ||
| cmpxchg_64.h | ||
| compat.h | ||
| cpu.h | ||
| cpu_debug.h | ||
| cpufeature.h | ||
| cpumask.h | ||
| cputime.h | ||
| current.h | ||
| debugreg.h | ||
| delay.h | ||
| desc.h | ||
| desc_defs.h | ||
| device.h | ||
| div64.h | ||
| dma-mapping.h | ||
| dma.h | ||
| dmi.h | ||
| do_timer.h | ||
| ds.h | ||
| dwarf2.h | ||
| e820.h | ||
| edac.h | ||
| efi.h | ||
| elf.h | ||
| emergency-restart.h | ||
| entry_arch.h | ||
| errno.h | ||
| fb.h | ||
| fcntl.h | ||
| fixmap.h | ||
| floppy.h | ||
| frame.h | ||
| ftrace.h | ||
| futex.h | ||
| gart.h | ||
| genapic.h | ||
| geode.h | ||
| gpio.h | ||
| hardirq.h | ||
| highmem.h | ||
| hpet.h | ||
| hugetlb.h | ||
| hw_irq.h | ||
| hypertransport.h | ||
| hypervisor.h | ||
| i387.h | ||
| i8253.h | ||
| i8259.h | ||
| ia32.h | ||
| ia32_unistd.h | ||
| idle.h | ||
| init.h | ||
| io.h | ||
| io_32.h | ||
| io_64.h | ||
| io_apic.h | ||
| ioctl.h | ||
| ioctls.h | ||
| iomap.h | ||
| iommu.h | ||
| ipcbuf.h | ||
| ipi.h | ||
| irq.h | ||
| irq_regs.h | ||
| irq_remapping.h | ||
| irq_vectors.h | ||
| irqflags.h | ||
| ist.h | ||
| k8.h | ||
| kdebug.h | ||
| kexec.h | ||
| kgdb.h | ||
| kmap_types.h | ||
| kmemcheck.h | ||
| kprobes.h | ||
| kvm.h | ||
| kvm_host.h | ||
| kvm_para.h | ||
| kvm_x86_emulate.h | ||
| ldt.h | ||
| lguest.h | ||
| lguest_hcall.h | ||
| linkage.h | ||
| local.h | ||
| mach_timer.h | ||
| mach_traps.h | ||
| math_emu.h | ||
| mc146818rtc.h | ||
| mca.h | ||
| mca_dma.h | ||
| mce.h | ||
| microcode.h | ||
| mman.h | ||
| mmconfig.h | ||
| mmu.h | ||
| mmu_context.h | ||
| mmx.h | ||
| mmzone.h | ||
| mmzone_32.h | ||
| mmzone_64.h | ||
| module.h | ||
| mpspec.h | ||
| mpspec_def.h | ||
| msgbuf.h | ||
| msidef.h | ||
| msr-index.h | ||
| msr.h | ||
| mtrr.h | ||
| mutex.h | ||
| mutex_32.h | ||
| mutex_64.h | ||
| nmi.h | ||
| nops.h | ||
| numa.h | ||
| numa_32.h | ||
| numa_64.h | ||
| numaq.h | ||
| olpc.h | ||
| page.h | ||
| page_32.h | ||
| page_32_types.h | ||
| page_64.h | ||
| page_64_types.h | ||
| page_types.h | ||
| param.h | ||
| paravirt.h | ||
| parport.h | ||
| pat.h | ||
| pci-direct.h | ||
| pci-functions.h | ||
| pci.h | ||
| pci_64.h | ||
| pci_x86.h | ||
| percpu.h | ||
| perf_counter.h | ||
| pgalloc.h | ||
| pgtable-2level.h | ||
| pgtable-2level_types.h | ||
| pgtable-3level.h | ||
| pgtable-3level_types.h | ||
| pgtable.h | ||
| pgtable_32.h | ||
| pgtable_32_types.h | ||
| pgtable_64.h | ||
| pgtable_64_types.h | ||
| pgtable_types.h | ||
| poll.h | ||
| posix_types.h | ||
| posix_types_32.h | ||
| posix_types_64.h | ||
| prctl.h | ||
| processor-cyrix.h | ||
| processor-flags.h | ||
| processor.h | ||
| proto.h | ||
| ptrace-abi.h | ||
| ptrace.h | ||
| pvclock-abi.h | ||
| pvclock.h | ||
| rdc321x_defs.h | ||
| reboot.h | ||
| reboot_fixups.h | ||
| required-features.h | ||
| resource.h | ||
| resume-trace.h | ||
| rio.h | ||
| rtc.h | ||
| rwlock.h | ||
| rwsem.h | ||
| scatterlist.h | ||
| seccomp.h | ||
| seccomp_32.h | ||
| seccomp_64.h | ||
| sections.h | ||
| segment.h | ||
| sembuf.h | ||
| serial.h | ||
| setup.h | ||
| setup_arch.h | ||
| shmbuf.h | ||
| shmparam.h | ||
| sigcontext.h | ||
| sigcontext32.h | ||
| sigframe.h | ||
| siginfo.h | ||
| signal.h | ||
| smp.h | ||
| smpboot_hooks.h | ||
| socket.h | ||
| sockios.h | ||
| sparsemem.h | ||
| spinlock.h | ||
| spinlock_types.h | ||
| srat.h | ||
| stackprotector.h | ||
| stacktrace.h | ||
| stat.h | ||
| statfs.h | ||
| string.h | ||
| string_32.h | ||
| string_64.h | ||
| suspend.h | ||
| suspend_32.h | ||
| suspend_64.h | ||
| svm.h | ||
| swab.h | ||
| swiotlb.h | ||
| sync_bitops.h | ||
| sys_ia32.h | ||
| syscall.h | ||
| syscalls.h | ||
| system.h | ||
| system_64.h | ||
| tce.h | ||
| termbits.h | ||
| termios.h | ||
| thread_info.h | ||
| time.h | ||
| timer.h | ||
| timex.h | ||
| tlb.h | ||
| tlbflush.h | ||
| topology.h | ||
| trampoline.h | ||
| traps.h | ||
| tsc.h | ||
| types.h | ||
| uaccess.h | ||
| uaccess_32.h | ||
| uaccess_64.h | ||
| ucontext.h | ||
| unaligned.h | ||
| unistd.h | ||
| unistd_32.h | ||
| unistd_64.h | ||
| user.h | ||
| user32.h | ||
| user_32.h | ||
| user_64.h | ||
| vdso.h | ||
| vga.h | ||
| vgtod.h | ||
| virtext.h | ||
| vm86.h | ||
| vmi.h | ||
| vmi_time.h | ||
| vmware.h | ||
| vmx.h | ||
| vsyscall.h | ||
| xcr.h | ||
| xor.h | ||
| xor_32.h | ||
| xor_64.h | ||
| xsave.h | ||