4.14-stable review patch. If anyone has any objections, please let me know.
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[ Upstream commit ffca395b11c4a5a6df6d6345f794b0e3d578e2d0 ]
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: d3ca587404b3 ("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 Signed-off-by: Sasha Levin sashal@kernel.org --- arch/powerpc/mm/fault.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c index 6e1e39035380..52863deed65d 100644 --- a/arch/powerpc/mm/fault.c +++ b/arch/powerpc/mm/fault.c @@ -215,7 +215,9 @@ static int mm_fault_error(struct pt_regs *regs, unsigned long addr, int fault) 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",