Merge remote-tracking branch 'remotes/fslc/4.9-2.3.x-imx' into toradex_4.9-2.3.x-imx-next

Conflicts:
	sound/soc/codecs/sgtl5000.c
	sound/soc/fsl/imx-sgtl5000.c

1 files changed, 26 insertions, 6 deletions

diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/signal_64.c
index d929afab7b24..aa6cc2bfa69d 100644
--- a/arch/powerpc/kernel/signal_64.c
+++ b/arch/powerpc/kernel/signal_64.c
@@ -469,8 +469,10 @@ static long restore_tm_sigcontexts(struct task_struct *tsk,
 	err |= __get_user(tsk->thread.ckpt_regs.ccr,
 			  &sc->gp_regs[PT_CCR]);
 
+	/* Don't allow userspace to set the trap value */
+	regs->trap = 0;
+
 	/* These regs are not checkpointed; they can go in 'regs'. */
-	err |= __get_user(regs->trap, &sc->gp_regs[PT_TRAP]);
 	err |= __get_user(regs->dar, &sc->gp_regs[PT_DAR]);
 	err |= __get_user(regs->dsisr, &sc->gp_regs[PT_DSISR]);
 	err |= __get_user(regs->result, &sc->gp_regs[PT_RESULT]);
@@ -741,17 +743,35 @@ int sys_rt_sigreturn(unsigned long r3, unsigned long r4, unsigned long r5,
 	if (MSR_TM_ACTIVE(msr)) {
 		/* We recheckpoint on return. */
 		struct ucontext __user *uc_transact;
+
+		/* Trying to start TM on non TM system */
+		if (!cpu_has_feature(CPU_FTR_TM))
+			goto badframe;
+
 		if (__get_user(uc_transact, &uc->uc_link))
 			goto badframe;
 		if (restore_tm_sigcontexts(current, &uc->uc_mcontext,
 					   &uc_transact->uc_mcontext))
 			goto badframe;
-	}
-	else
-	/* Fall through, for non-TM restore */
+	} else
 #endif
-	if (restore_sigcontext(current, NULL, 1, &uc->uc_mcontext))
-		goto badframe;
+	{
+		/*
+		 * Fall through, for non-TM restore
+		 *
+		 * Unset MSR[TS] on the thread regs since MSR from user
+		 * context does not have MSR active, and recheckpoint was
+		 * not called since restore_tm_sigcontexts() was not called
+		 * also.
+		 *
+		 * If not unsetting it, the code can RFID to userspace with
+		 * MSR[TS] set, but without CPU in the proper state,
+		 * causing a TM bad thing.
+		 */
+		current->thread.regs->msr &= ~MSR_TS_MASK;
+		if (restore_sigcontext(current, NULL, 1, &uc->uc_mcontext))
+			goto badframe;
+	}
 
 	if (restore_altstack(&uc->uc_stack))
 		goto badframe;