ce56a86e2a
Currently, it is possible to mmap() any offset from /dev/mem. If a program mmaps() /dev/mem offsets outside of the addressable limits of a system, the page table can be corrupted by setting reserved bits. For example if you mmap() offset 0x0001000000000000 of /dev/mem on an x86_64 system with a 48-bit bus, the page fault handler will be called with error_code set to RSVD. The kernel then crashes with a page table corruption error. This change prevents this page table corruption on x86 by refusing to mmap offsets higher than the highest valid address in the system. Signed-off-by: Craig Bergstrom <craigb@google.com> Cc: Andrew Morton <akpm@linux-foundation.org> 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: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hp.com> Cc: dsafonov@virtuozzo.com Cc: kirill.shutemov@linux.intel.com Cc: mhocko@suse.com Cc: oleg@redhat.com Link: http://lkml.kernel.org/r/20171019192856.39672-1-craigb@google.com Signed-off-by: Ingo Molnar <mingo@kernel.org> |
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| boot | ||
| configs | ||
| crypto | ||
| entry | ||
| events | ||
| hyperv | ||
| ia32 | ||
| include | ||
| kernel | ||
| kvm | ||
| lib | ||
| math-emu | ||
| mm | ||
| net | ||
| oprofile | ||
| pci | ||
| platform | ||
| power | ||
| purgatory | ||
| ras | ||
| realmode | ||
| tools | ||
| um | ||
| video | ||
| xen | ||
| .gitignore | ||
| Kbuild | ||
| Kconfig | ||
| Kconfig.cpu | ||
| Kconfig.debug | ||
| Makefile | ||
| Makefile.um | ||
| Makefile_32.cpu | ||