From b90136e442c889a7344992acc34764729936ab92 Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Mon, 18 Sep 2017 21:43:36 -0500 Subject: [PATCH 058/242] x86/xen: Add unwind hint annotations MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit CVE-2017-5754 Add unwind hint annotations to the xen head code so the ORC unwinder can read head_64.o. hypercall_page needs empty annotations at 32-byte intervals to match the 'xen_hypercall_*' ELF functions at those locations. Signed-off-by: Josh Poimboeuf Cc: Andy Lutomirski Cc: Boris Ostrovsky Cc: Jiri Slaby Cc: Juergen Gross Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/70ed2eb516fe9266be766d953f93c2571bca88cc.1505764066.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar (cherry picked from commit abbe1cac6214d81d2f4e149aba64a8760703144e) Signed-off-by: Andy Whitcroft Signed-off-by: Kleber Sacilotto de Souza (cherry picked from commit 9f099a90cb39eaff9b3187e8a6d8151c8af53db1) Signed-off-by: Fabian Grünbichler --- arch/x86/xen/xen-head.S | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/arch/x86/xen/xen-head.S b/arch/x86/xen/xen-head.S index 2f0cff2cc265..ad189ab2c329 100644 --- a/arch/x86/xen/xen-head.S +++ b/arch/x86/xen/xen-head.S @@ -9,6 +9,7 @@ #include #include #include +#include #include #include @@ -19,6 +20,7 @@ #ifdef CONFIG_XEN_PV __INIT ENTRY(startup_xen) + UNWIND_HINT_EMPTY cld /* Clear .bss */ @@ -40,7 +42,10 @@ END(startup_xen) .pushsection .text .balign PAGE_SIZE ENTRY(hypercall_page) - .skip PAGE_SIZE + .rept (PAGE_SIZE / 32) + UNWIND_HINT_EMPTY + .skip 32 + .endr #define HYPERCALL(n) \ .equ xen_hypercall_##n, hypercall_page + __HYPERVISOR_##n * 32; \ -- 2.14.2