From 441cedab2dfca18fe4983cbc795de04536ed421e Mon Sep 17 00:00:00 2001 From: Andy Lutomirski Date: Wed, 26 Jun 2019 21:45:08 -0700 Subject: x86/vsyscall: Add __ro_after_init to global variables The vDSO is only configurable by command-line options, so make its global variables __ro_after_init. This seems highly unlikely to ever stop an exploit, but it's nicer anyway. Signed-off-by: Andy Lutomirski Signed-off-by: Thomas Gleixner Reviewed-by: Kees Cook Cc: Florian Weimer Cc: Jann Horn Cc: Borislav Petkov Cc: Kernel Hardening Cc: Peter Zijlstra Link: https://lkml.kernel.org/r/a386925835e49d319e70c4d7404b1f6c3c2e3702.1561610354.git.luto@kernel.org --- arch/x86/entry/vsyscall/vsyscall_64.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/entry/vsyscall/vsyscall_64.c b/arch/x86/entry/vsyscall/vsyscall_64.c index 9c58ab807aeb..07003f3f1bfc 100644 --- a/arch/x86/entry/vsyscall/vsyscall_64.c +++ b/arch/x86/entry/vsyscall/vsyscall_64.c @@ -42,7 +42,7 @@ #define CREATE_TRACE_POINTS #include "vsyscall_trace.h" -static enum { EMULATE, XONLY, NONE } vsyscall_mode = +static enum { EMULATE, XONLY, NONE } vsyscall_mode __ro_after_init = #ifdef CONFIG_LEGACY_VSYSCALL_NONE NONE; #elif defined(CONFIG_LEGACY_VSYSCALL_XONLY) @@ -305,7 +305,7 @@ static const char *gate_vma_name(struct vm_area_struct *vma) static const struct vm_operations_struct gate_vma_ops = { .name = gate_vma_name, }; -static struct vm_area_struct gate_vma = { +static struct vm_area_struct gate_vma __ro_after_init = { .vm_start = VSYSCALL_ADDR, .vm_end = VSYSCALL_ADDR + PAGE_SIZE, .vm_page_prot = PAGE_READONLY_EXEC, -- cgit v1.2.3