From c7ef01f56951b1c876069387c44e11575288f3d2 Mon Sep 17 00:00:00 2001 From: Vlastimil Babka Date: Tue, 19 Dec 2017 22:33:46 +0100 Subject: [PATCH 213/231] x86/dumpstack: Indicate in Oops whether PTI is configured and enabled MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit CVE-2017-5754 CONFIG_PAGE_TABLE_ISOLATION is relatively new and intrusive feature that may still have some corner cases which could take some time to manifest and be fixed. It would be useful to have Oops messages indicate whether it was enabled for building the kernel, and whether it was disabled during boot. Example of fully enabled: Oops: 0001 [#1] SMP PTI Example of enabled during build, but disabled during boot: Oops: 0001 [#1] SMP NOPTI We can decide to remove this after the feature has been tested in the field long enough. [ tglx: Made it use boot_cpu_has() as requested by Borislav ] Signed-off-by: Vlastimil Babka Signed-off-by: Thomas Gleixner Reviewed-by: Eduardo Valentin Acked-by: Dave Hansen Cc: Andy Lutomirski Cc: Andy Lutomirsky Cc: Boris Ostrovsky Cc: Borislav Petkov Cc: Brian Gerst Cc: Dave Hansen Cc: David Laight Cc: Denys Vlasenko Cc: Greg KH Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Juergen Gross Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Will Deacon Cc: aliguori@amazon.com Cc: bpetkov@suse.de Cc: daniel.gruss@iaik.tugraz.at Cc: hughd@google.com Cc: jkosina@suse.cz Cc: keescook@google.com Signed-off-by: Ingo Molnar (cherry picked from commit 5f26d76c3fd67c48806415ef8b1116c97beff8ba) Signed-off-by: Andy Whitcroft Signed-off-by: Kleber Sacilotto de Souza (cherry picked from commit 7edb91fcc96589ad6b80446ec3835f83ffabb710) Signed-off-by: Fabian Grünbichler --- arch/x86/kernel/dumpstack.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/dumpstack.c b/arch/x86/kernel/dumpstack.c index 2bdeb983b9d8..19a936e9b259 100644 --- a/arch/x86/kernel/dumpstack.c +++ b/arch/x86/kernel/dumpstack.c @@ -298,11 +298,13 @@ int __die(const char *str, struct pt_regs *regs, long err) unsigned long sp; #endif printk(KERN_DEFAULT - "%s: %04lx [#%d]%s%s%s%s\n", str, err & 0xffff, ++die_counter, + "%s: %04lx [#%d]%s%s%s%s%s\n", str, err & 0xffff, ++die_counter, IS_ENABLED(CONFIG_PREEMPT) ? " PREEMPT" : "", IS_ENABLED(CONFIG_SMP) ? " SMP" : "", debug_pagealloc_enabled() ? " DEBUG_PAGEALLOC" : "", - IS_ENABLED(CONFIG_KASAN) ? " KASAN" : ""); + IS_ENABLED(CONFIG_KASAN) ? " KASAN" : "", + IS_ENABLED(CONFIG_PAGE_TABLE_ISOLATION) ? + (boot_cpu_has(X86_FEATURE_PTI) ? " PTI" : " NOPTI") : ""); if (notify_die(DIE_OOPS, str, regs, err, current->thread.trap_nr, SIGSEGV) == NOTIFY_STOP) -- 2.14.2