x86/mm: Clean up the printk()s in show_fault_oops()

- Remove 'nx_warning' and 'smep_warning', which are just pointless obfuscation.
- Also convert to pr_crit().

Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180627090715.28076-1-dvyukov@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Dmitry Vyukov 2018-06-27 11:07:15 +02:00 committed by Ingo Molnar
parent b8c1e4293a
commit d79d0d8ad0
1 changed files with 4 additions and 7 deletions

View File

@ -641,11 +641,6 @@ static int is_f00f_bug(struct pt_regs *regs, unsigned long address)
return 0;
}
static const char nx_warning[] = KERN_CRIT
"kernel tried to execute NX-protected page - exploit attempt? (uid: %d)\n";
static const char smep_warning[] = KERN_CRIT
"unable to execute userspace code (SMEP?) (uid: %d)\n";
static void
show_fault_oops(struct pt_regs *regs, unsigned long error_code,
unsigned long address)
@ -664,11 +659,13 @@ show_fault_oops(struct pt_regs *regs, unsigned long error_code,
pte = lookup_address_in_pgd(pgd, address, &level);
if (pte && pte_present(*pte) && !pte_exec(*pte))
printk(nx_warning, from_kuid(&init_user_ns, current_uid()));
pr_crit("kernel tried to execute NX-protected page - exploit attempt? (uid: %d)\n",
from_kuid(&init_user_ns, current_uid()));
if (pte && pte_present(*pte) && pte_exec(*pte) &&
(pgd_flags(*pgd) & _PAGE_USER) &&
(__read_cr4() & X86_CR4_SMEP))
printk(smep_warning, from_kuid(&init_user_ns, current_uid()));
pr_crit("unable to execute userspace code (SMEP?) (uid: %d)\n",
from_kuid(&init_user_ns, current_uid()));
}
pr_alert("BUG: unable to handle kernel %s at %px\n",