diff options
Diffstat (limited to 'arch/x86/mm/fault.c')
| -rw-r--r-- | arch/x86/mm/fault.c | 40 |
1 files changed, 5 insertions, 35 deletions
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index 622d12ec7f08..f26ecabc9424 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -514,18 +514,19 @@ show_fault_oops(struct pt_regs *regs, unsigned long error_code, unsigned long ad if (error_code & X86_PF_INSTR) { unsigned int level; + bool nx, rw; pgd_t *pgd; pte_t *pte; pgd = __va(read_cr3_pa()); pgd += pgd_index(address); - pte = lookup_address_in_pgd(pgd, address, &level); + pte = lookup_address_in_pgd_attr(pgd, address, &level, &nx, &rw); - if (pte && pte_present(*pte) && !pte_exec(*pte)) + if (pte && pte_present(*pte) && (!pte_exec(*pte) || nx)) 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) && + if (pte && pte_present(*pte) && pte_exec(*pte) && !nx && (pgd_flags(*pgd) & _PAGE_USER) && (__read_cr4() & X86_CR4_SMEP)) pr_crit("unable to execute userspace code (SMEP?) (uid: %d)\n", @@ -723,39 +724,8 @@ kernelmode_fixup_or_oops(struct pt_regs *regs, unsigned long error_code, WARN_ON_ONCE(user_mode(regs)); /* Are we prepared to handle this kernel fault? */ - if (fixup_exception(regs, X86_TRAP_PF, error_code, address)) { - /* - * Any interrupt that takes a fault gets the fixup. This makes - * the below recursive fault logic only apply to a faults from - * task context. - */ - if (in_interrupt()) - return; - - /* - * Per the above we're !in_interrupt(), aka. task context. - * - * In this case we need to make sure we're not recursively - * faulting through the emulate_vsyscall() logic. - */ - if (current->thread.sig_on_uaccess_err && signal) { - sanitize_error_code(address, &error_code); - - set_signal_archinfo(address, error_code); - - if (si_code == SEGV_PKUERR) { - force_sig_pkuerr((void __user *)address, pkey); - } else { - /* XXX: hwpoison faults will set the wrong code. */ - force_sig_fault(signal, si_code, (void __user *)address); - } - } - - /* - * Barring that, we can do the fixup and be happy. - */ + if (fixup_exception(regs, X86_TRAP_PF, error_code, address)) return; - } /* * AMD erratum #91 manifests as a spurious page fault on a PREFETCH |