From 368b69a5b010cb00fc9ea04d588cff69af1a1359 Mon Sep 17 00:00:00 2001 From: Andy Lutomirski Date: Wed, 14 May 2014 16:23:13 -0700 Subject: [PATCH] x86, vdso: Fix an OOPS accessing the HPET mapping w/o an HPET The oops can be triggered in qemu using -no-hpet (but not nohpet) by running a 32-bit program and reading a couple of pages before the vdso. This should send SIGBUS instead of OOPSing. The bug was introduced by: commit 7a59ed415f5b57469e22e41fc4188d5399e0b194 Author: Stefani Seibold Date: Mon Mar 17 23:22:09 2014 +0100 x86, vdso: Add 32 bit VDSO time support for 32 bit kernel which is new in 3.15. Signed-off-by: Andy Lutomirski Link: http://lkml.kernel.org/r/e99025d887d6670b6c4d81e6ccfeeb83770b21e9.1400109621.git.luto@amacapital.net Signed-off-by: H. Peter Anvin --- arch/x86/vdso/vdso32-setup.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/x86/vdso/vdso32-setup.c b/arch/x86/vdso/vdso32-setup.c index e1f220e3ca68..310c5f0dbef1 100644 --- a/arch/x86/vdso/vdso32-setup.c +++ b/arch/x86/vdso/vdso32-setup.c @@ -155,6 +155,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) unsigned long addr; int ret = 0; struct vm_area_struct *vma; + static struct page *no_pages[] = {NULL}; #ifdef CONFIG_X86_X32_ABI if (test_thread_flag(TIF_X32)) @@ -193,7 +194,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) addr - VDSO_OFFSET(VDSO_PREV_PAGES), VDSO_OFFSET(VDSO_PREV_PAGES), VM_READ, - NULL); + no_pages); if (IS_ERR(vma)) { ret = PTR_ERR(vma);