diff options
| author | Kees Cook <keescook@chromium.org> | 2016-05-09 23:22:04 +0300 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2016-05-10 11:12:02 +0300 |
| commit | 434a6c9f90f7ab5ade619455df01ef5ebea533ee (patch) | |
| tree | 901c7e2407c028795974603ee8daf52c97d56a98 | |
| parent | 36a39ac967a548154a0fe44d71cb0063fa05010f (diff) | |
| download | linux-434a6c9f90f7ab5ade619455df01ef5ebea533ee.tar.xz | |
x86/KASLR: Initialize mapping_info every time
As it turns out, mapping_info DOES need to be initialized every
time, because pgt_data address could be changed during kernel
relocation. So it can not be build time assigned.
Without this, page tables were not being corrected updated, which
could cause reboots when a physical address beyond 2G was chosen.
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: kernel-hardening@lists.openwall.com
Cc: lasse.collin@tukaani.org
Link: http://lkml.kernel.org/r/1462825332-10505-2-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
| -rw-r--r-- | arch/x86/boot/compressed/pagetable.c | 16 |
1 files changed, 5 insertions, 11 deletions
diff --git a/arch/x86/boot/compressed/pagetable.c b/arch/x86/boot/compressed/pagetable.c index 3c99051566a9..34b95df14e69 100644 --- a/arch/x86/boot/compressed/pagetable.c +++ b/arch/x86/boot/compressed/pagetable.c @@ -90,23 +90,17 @@ static void prepare_level4(void) } /* - * Mapping information structure passed to kernel_ident_mapping_init(). - * Since this never changes, there's no reason to repeatedly fill it - * in on the stack when calling add_identity_map(). - */ -static struct x86_mapping_info mapping_info = { - .alloc_pgt_page = alloc_pgt_page, - .context = &pgt_data, - .pmd_flag = __PAGE_KERNEL_LARGE_EXEC, -}; - -/* * Adds the specified range to what will become the new identity mappings. * Once all ranges have been added, the new mapping is activated by calling * finalize_identity_maps() below. */ void add_identity_map(unsigned long start, unsigned long size) { + struct x86_mapping_info mapping_info = { + .alloc_pgt_page = alloc_pgt_page, + .context = &pgt_data, + .pmd_flag = __PAGE_KERNEL_LARGE_EXEC, + }; unsigned long end = start + size; /* Make sure we have a top level page table ready to use. */ |