3.14-stable review patch. If anyone has any objections, please let me know.
------------------ From: Stephen Smalley <[email protected]> commit ab76f7b4ab2397ffdd2f1eb07c55697d19991d10 upstream. Unused space between the end of __ex_table and the start of rodata can be left W+x in the kernel page tables. Extend the setting of the NX bit to cover this gap by starting from text_end rather than rodata_start. Before: ---[ High Kernel Mapping ]--- 0xffffffff80000000-0xffffffff81000000 16M pmd 0xffffffff81000000-0xffffffff81600000 6M ro PSE GLB x pmd 0xffffffff81600000-0xffffffff81754000 1360K ro GLB x pte 0xffffffff81754000-0xffffffff81800000 688K RW GLB x pte 0xffffffff81800000-0xffffffff81a00000 2M ro PSE GLB NX pmd 0xffffffff81a00000-0xffffffff81b3b000 1260K ro GLB NX pte 0xffffffff81b3b000-0xffffffff82000000 4884K RW GLB NX pte 0xffffffff82000000-0xffffffff82200000 2M RW PSE GLB NX pmd 0xffffffff82200000-0xffffffffa0000000 478M pmd After: ---[ High Kernel Mapping ]--- 0xffffffff80000000-0xffffffff81000000 16M pmd 0xffffffff81000000-0xffffffff81600000 6M ro PSE GLB x pmd 0xffffffff81600000-0xffffffff81754000 1360K ro GLB x pte 0xffffffff81754000-0xffffffff81800000 688K RW GLB NX pte 0xffffffff81800000-0xffffffff81a00000 2M ro PSE GLB NX pmd 0xffffffff81a00000-0xffffffff81b3b000 1260K ro GLB NX pte 0xffffffff81b3b000-0xffffffff82000000 4884K RW GLB NX pte 0xffffffff82000000-0xffffffff82200000 2M RW PSE GLB NX pmd 0xffffffff82200000-0xffffffffa0000000 478M pmd Signed-off-by: Stephen Smalley <[email protected]> Acked-by: Kees Cook <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Mike Galbraith <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: [email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- arch/x86/mm/init_64.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/arch/x86/mm/init_64.c +++ b/arch/x86/mm/init_64.c @@ -1131,7 +1131,7 @@ void mark_rodata_ro(void) * has been zapped already via cleanup_highmem(). */ all_end = roundup((unsigned long)_brk_end, PMD_SIZE); - set_memory_nx(rodata_start, (all_end - rodata_start) >> PAGE_SHIFT); + set_memory_nx(text_end, (all_end - text_end) >> PAGE_SHIFT); rodata_test(); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
