powerpc/mm: Fix reporting of kernel execute faults on the 8xx

On the 8xx, no-execute is set via PPP bits in the PTE. Therefore
a no-exec fault generates DSISR_PROTFAULT error bits,
not DSISR_NOEXEC_OR_G.

This patch adds DSISR_PROTFAULT in the test mask.

Fixes: d3ca587404 ("powerpc/mm: Fix reporting of kernel execute faults")
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Christophe Leroy 2018-11-28 09:27:04 +00:00 committed by Michael Ellerman
parent ab66dcc76d
commit ffca395b11
1 changed files with 3 additions and 1 deletions

View File

@ -226,7 +226,9 @@ static int mm_fault_error(struct pt_regs *regs, unsigned long addr,
static bool bad_kernel_fault(bool is_exec, unsigned long error_code,
unsigned long address)
{
if (is_exec && (error_code & (DSISR_NOEXEC_OR_G | DSISR_KEYFAULT))) {
/* NX faults set DSISR_PROTFAULT on the 8xx, DSISR_NOEXEC_OR_G on others */
if (is_exec && (error_code & (DSISR_NOEXEC_OR_G | DSISR_KEYFAULT |
DSISR_PROTFAULT))) {
printk_ratelimited(KERN_CRIT "kernel tried to execute"
" exec-protected page (%lx) -"
"exploit attempt? (uid: %d)\n",