diff options
author | Russell Currey <ruscur@russell.cc> | 2019-05-02 09:39:47 +0200 |
---|---|---|
committer | Michael Ellerman <mpe@ellerman.id.au> | 2019-05-02 18:54:45 +0200 |
commit | 453d87f6a8aed827f5ebb1708a4cea458fd68d23 (patch) | |
tree | bc0424487d4f512ca6313ac84b03568784b19965 /arch/powerpc/mm/pgtable_32.c | |
parent | powerpc/mm/ptdump: Wrap seq_printf() to handle NULL pointers (diff) | |
download | linux-453d87f6a8aed827f5ebb1708a4cea458fd68d23.tar.xz linux-453d87f6a8aed827f5ebb1708a4cea458fd68d23.zip |
powerpc/mm: Warn if W+X pages found on boot
Implement code to walk all pages and warn if any are found to be both
writable and executable. Depends on STRICT_KERNEL_RWX enabled, and is
behind the DEBUG_WX config option.
This only runs on boot and has no runtime performance implications.
Very heavily influenced (and in some cases copied verbatim) from the
ARM64 code written by Laura Abbott (thanks!), since our ptdump
infrastructure is similar.
Signed-off-by: Russell Currey <ruscur@russell.cc>
[mpe: Fixup build error when disabled]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/mm/pgtable_32.c')
-rw-r--r-- | arch/powerpc/mm/pgtable_32.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/arch/powerpc/mm/pgtable_32.c b/arch/powerpc/mm/pgtable_32.c index 2e67f9a1430b..16ada373b32b 100644 --- a/arch/powerpc/mm/pgtable_32.c +++ b/arch/powerpc/mm/pgtable_32.c @@ -396,6 +396,9 @@ void mark_rodata_ro(void) PFN_DOWN((unsigned long)__start_rodata); change_page_attr(page, numpages, PAGE_KERNEL_RO); + + // mark_initmem_nx() should have already run by now + ptdump_check_wx(); } #endif |