diff options
author | James Morris <james.l.morris@oracle.com> | 2014-11-19 21:32:12 +1100 |
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committer | James Morris <james.l.morris@oracle.com> | 2014-11-19 21:32:12 +1100 |
commit | b10778a00d40b3d9fdaaf5891e802794781ff71c (patch) | |
tree | 6ba4cbac86eecedc3f30650e7f764ecf00c83898 /arch/x86/mm/fault.c | |
parent | 594081ee7145cc30a3977cb4e218f81213b63dc5 (diff) | |
parent | bfe01a5ba2490f299e1d2d5508cbbbadd897bbe9 (diff) |
Merge commit 'v3.17' into next
Diffstat (limited to 'arch/x86/mm/fault.c')
-rw-r--r-- | arch/x86/mm/fault.c | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index 36642793e31..a2419468151 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -577,6 +577,8 @@ static int is_f00f_bug(struct pt_regs *regs, unsigned long address) 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, @@ -597,6 +599,10 @@ show_fault_oops(struct pt_regs *regs, unsigned long error_code, if (pte && pte_present(*pte) && !pte_exec(*pte)) printk(nx_warning, 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())); } printk(KERN_ALERT "BUG: unable to handle kernel "); @@ -1212,7 +1218,8 @@ good_area: /* * If for any reason at all we couldn't handle the fault, * make sure we exit gracefully rather than endlessly redo - * the fault: + * the fault. Since we never set FAULT_FLAG_RETRY_NOWAIT, if + * we get VM_FAULT_RETRY back, the mmap_sem has been unlocked. */ fault = handle_mm_fault(mm, vma, address, flags); |