x86/boot/64: Verify alignment of the LOAD segment

Since the x86-64 kernel must be aligned to 2MB, refuse to boot the
kernel if the alignment of the LOAD segment isn't a multiple of 2MB.

Signed-off-by: H.J. Lu <[email protected]>
Cc: Andy Shevchenko <[email protected]>
Cc: Eric Biederman <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Juergen Gross <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Kirill A. Shutemov <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Link: http://lkml.kernel.org/r/CAMe9rOrR7xSJgUfiCoZLuqWUwymRxXPoGBW38%2BpN%3D9g%[email protected]
Signed-off-by: Ingo Molnar <[email protected]>

diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c
index 98761a1576ceb5c21b2d8c7e98c1217fd48abb26..252fee32081662ce3bf21d71158969afc9c596b3 100644 (file)
--- a/arch/x86/boot/compressed/misc.c
+++ b/arch/x86/boot/compressed/misc.c
@@ -309,6 +309,10 @@ static void parse_elf(void *output)
 
                switch (phdr->p_type) {
                case PT_LOAD:
+#ifdef CONFIG_X86_64
+                       if ((phdr->p_align % 0x200000) != 0)
+                               error("Alignment of LOAD segment isn't multiple of 2MB");
+#endif
 #ifdef CONFIG_RELOCATABLE
                        dest = output;
                        dest += (phdr->p_paddr - LOAD_PHYSICAL_ADDR);