e1a58320a3
Warn on any residual W+X mappings after setting NX if DEBUG_WX is enabled. Introduce a separate X86_PTDUMP_CORE config that enables the code for dumping the page tables without enabling the debugfs interface, so that DEBUG_WX can be enabled without exposing the debugfs interface. Switch EFI_PGT_DUMP to using X86_PTDUMP_CORE so that it also does not require enabling the debugfs interface. On success it prints this to the kernel log: x86/mm: Checked W+X mappings: passed, no W+X pages found. On failure it prints a warning and a count of the failed pages: ------------[ cut here ]------------ WARNING: CPU: 1 PID: 1 at arch/x86/mm/dump_pagetables.c:226 note_page+0x610/0x7b0() x86/mm: Found insecure W+X mapping at address ffffffff81755000/__stop___ex_table+0xfa8/0xabfa8 [...] Call Trace: [<ffffffff81380a5f>] dump_stack+0x44/0x55 [<ffffffff8109d3f2>] warn_slowpath_common+0x82/0xc0 [<ffffffff8109d48c>] warn_slowpath_fmt+0x5c/0x80 [<ffffffff8106cfc9>] ? note_page+0x5c9/0x7b0 [<ffffffff8106d010>] note_page+0x610/0x7b0 [<ffffffff8106d409>] ptdump_walk_pgd_level_core+0x259/0x3c0 [<ffffffff8106d5a7>] ptdump_walk_pgd_level_checkwx+0x17/0x20 [<ffffffff81063905>] mark_rodata_ro+0xf5/0x100 [<ffffffff817415a0>] ? rest_init+0x80/0x80 [<ffffffff817415bd>] kernel_init+0x1d/0xe0 [<ffffffff8174cd1f>] ret_from_fork+0x3f/0x70 [<ffffffff817415a0>] ? rest_init+0x80/0x80 ---[ end trace a1f23a1e42a2ac76 ]--- x86/mm: Checked W+X mappings: FAILED, 171 W+X pages found. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Acked-by: Kees Cook <keescook@chromium.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Arjan van de Ven <arjan@linux.intel.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: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Link: http://lkml.kernel.org/r/1444064120-11450-1-git-send-email-sds@tycho.nsa.gov [ Improved the Kconfig help text and made the new option default-y if CONFIG_DEBUG_RODATA=y, because it already found buggy mappings, so we really want people to have this on by default. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
36 lines
1 KiB
Makefile
36 lines
1 KiB
Makefile
obj-y := init.o init_$(BITS).o fault.o ioremap.o extable.o pageattr.o mmap.o \
|
|
pat.o pgtable.o physaddr.o gup.o setup_nx.o
|
|
|
|
# Make sure __phys_addr has no stackprotector
|
|
nostackp := $(call cc-option, -fno-stack-protector)
|
|
CFLAGS_physaddr.o := $(nostackp)
|
|
CFLAGS_setup_nx.o := $(nostackp)
|
|
|
|
CFLAGS_fault.o := -I$(src)/../include/asm/trace
|
|
|
|
obj-$(CONFIG_X86_PAT) += pat_rbtree.o
|
|
obj-$(CONFIG_SMP) += tlb.o
|
|
|
|
obj-$(CONFIG_X86_32) += pgtable_32.o iomap_32.o
|
|
|
|
obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o
|
|
obj-$(CONFIG_X86_PTDUMP_CORE) += dump_pagetables.o
|
|
|
|
obj-$(CONFIG_HIGHMEM) += highmem_32.o
|
|
|
|
obj-$(CONFIG_KMEMCHECK) += kmemcheck/
|
|
|
|
KASAN_SANITIZE_kasan_init_$(BITS).o := n
|
|
obj-$(CONFIG_KASAN) += kasan_init_$(BITS).o
|
|
|
|
obj-$(CONFIG_MMIOTRACE) += mmiotrace.o
|
|
mmiotrace-y := kmmio.o pf_in.o mmio-mod.o
|
|
obj-$(CONFIG_MMIOTRACE_TEST) += testmmiotrace.o
|
|
|
|
obj-$(CONFIG_NUMA) += numa.o numa_$(BITS).o
|
|
obj-$(CONFIG_AMD_NUMA) += amdtopology.o
|
|
obj-$(CONFIG_ACPI_NUMA) += srat.o
|
|
obj-$(CONFIG_NUMA_EMU) += numa_emulation.o
|
|
|
|
obj-$(CONFIG_X86_INTEL_MPX) += mpx.o
|