Re: [RFC v6 35/62] powerpc: Deliver SEGV signal on pkey violation

On Sat, Aug 19, 2017 at 02:09:58PM -0500, Eric W. Biederman wrote:

Ram Pai [off-list ref] writes:

quoted

diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index d4e545d..fe1e7c7 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c

@@ -20,6 +20,7 @@
 #include <linux/sched/debug.h>
 #include <linux/kernel.h>
 #include <linux/mm.h>
+#include <linux/pkeys.h>
 #include <linux/stddef.h>
 #include <linux/unistd.h>
 #include <linux/ptrace.h>

@@ -247,6 +248,15 @@ void user_single_step_siginfo(struct task_struct *tsk,
 	info->si_addr = (void __user *)regs->nip;
 }
 
+#ifdef CONFIG_PPC64_MEMORY_PROTECTION_KEYS
+static void fill_sig_info_pkey(int si_code, siginfo_t *info, unsigned long addr)
+{
+	if (si_code != SEGV_PKUERR)
+		return;

Given that SEGV_PKUERR is a signal specific si_code this test is
insufficient to detect an pkey error.  You also need to check
that signr == SIGSEGV

true. will make it a more precise check.

Thanks
RP