Merge tag 'powerpc-5.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:

 - Enable KFENCE for 32-bit.

 - Implement EBPF for 32-bit.

 - Convert 32-bit to do interrupt entry/exit in C.

 - Convert 64-bit BookE to do interrupt entry/exit in C.

 - Changes to our signal handling code to use user_access_begin/end()
   more extensively.

 - Add support for time namespaces (CONFIG_TIME_NS)

 - A series of fixes that allow us to reenable STRICT_KERNEL_RWX.

 - Other smaller features, fixes & cleanups.

Thanks to Alexey Kardashevskiy, Andreas Schwab, Andrew Donnellan, Aneesh
Kumar K.V, Athira Rajeev, Bhaskar Chowdhury, Bixuan Cui, Cédric Le
Goater, Chen Huang, Chris Packham, Christophe Leroy, Christopher M.
Riedl, Colin Ian King, Dan Carpenter, Daniel Axtens, Daniel Henrique
Barboza, David Gibson, Davidlohr Bueso, Denis Efremov, dingsenjie,
Dmitry Safonov, Dominic DeMarco, Fabiano Rosas, Ganesh Goudar, Geert
Uytterhoeven, Geetika Moolchandani, Greg Kurz, Guenter Roeck, Haren
Myneni, He Ying, Jiapeng Chong, Jordan Niethe, Laurent Dufour, Lee
Jones, Leonardo Bras, Li Huafei, Madhavan Srinivasan, Mahesh Salgaonkar,
Masahiro Yamada, Nathan Chancellor, Nathan Lynch, Nicholas Piggin,
Oliver O'Halloran, Paul Menzel, Pu Lehui, Randy Dunlap, Ravi Bangoria,
Rosen Penev, Russell Currey, Santosh Sivaraj, Sebastian Andrzej Siewior,
Segher Boessenkool, Shivaprasad G Bhat, Srikar Dronamraju, Stephen
Rothwell, Thadeu Lima de Souza Cascardo, Thomas Gleixner, Tony Ambardar,
Tyrel Datwyler, Vaibhav Jain, Vincenzo Frascino, Xiongwei Song, Yang Li,
Yu Kuai, and Zhang Yunkai.

* tag 'powerpc-5.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (302 commits)
  powerpc/signal32: Fix erroneous SIGSEGV on RT signal return
  powerpc: Avoid clang uninitialized warning in __get_user_size_allowed
  powerpc/papr_scm: Mark nvdimm as unarmed if needed during probe
  powerpc/kvm: Fix build error when PPC_MEM_KEYS/PPC_PSERIES=n
  powerpc/kasan: Fix shadow start address with modules
  powerpc/kernel/iommu: Use largepool as a last resort when !largealloc
  powerpc/kernel/iommu: Align size for IOMMU_PAGE_SIZE() to save TCEs
  powerpc/44x: fix spelling mistake in Kconfig "varients" -> "variants"
  powerpc/iommu: Annotate nested lock for lockdep
  powerpc/iommu: Do not immediately panic when failed IOMMU table allocation
  powerpc/iommu: Allocate it_map by vmalloc
  selftests/powerpc: remove unneeded semicolon
  powerpc/64s: remove unneeded semicolon
  powerpc/eeh: remove unneeded semicolon
  powerpc/selftests: Add selftest to test concurrent perf/ptrace events
  powerpc/selftests/perf-hwbreak: Add testcases for 2nd DAWR
  powerpc/selftests/perf-hwbreak: Coalesce event creation code
  powerpc/selftests/ptrace-hwbreak: Add testcases for 2nd DAWR
  powerpc/configs: Add IBMVNIC to some 64-bit configs
  selftests/powerpc: Add uaccess flush test
  ...

1 files changed, 189 insertions, 130 deletions

diff --git a/arch/powerpc/kernel/signal_64.c b/arch/powerpc/kernel/signal_64.c
index f9e4a1ac440f..dca66481d0c2 100644
--- a/arch/powerpc/kernel/signal_64.c
+++ b/arch/powerpc/kernel/signal_64.c
@@ -79,13 +79,36 @@ static elf_vrreg_t __user *sigcontext_vmx_regs(struct sigcontext __user *sc)
 }
 #endif
 
+static void prepare_setup_sigcontext(struct task_struct *tsk)
+{
+#ifdef CONFIG_ALTIVEC
+	/* save altivec registers */
+	if (tsk->thread.used_vr)
+		flush_altivec_to_thread(tsk);
+	if (cpu_has_feature(CPU_FTR_ALTIVEC))
+		tsk->thread.vrsave = mfspr(SPRN_VRSAVE);
+#endif /* CONFIG_ALTIVEC */
+
+	flush_fp_to_thread(tsk);
+
+#ifdef CONFIG_VSX
+	if (tsk->thread.used_vsr)
+		flush_vsx_to_thread(tsk);
+#endif /* CONFIG_VSX */
+}
+
 /*
  * Set up the sigcontext for the signal frame.
  */
 
-static long setup_sigcontext(struct sigcontext __user *sc,
-		struct task_struct *tsk, int signr, sigset_t *set,
-		unsigned long handler, int ctx_has_vsx_region)
+#define unsafe_setup_sigcontext(sc, tsk, signr, set, handler, ctx_has_vsx_region, label)\
+do {											\
+	if (__unsafe_setup_sigcontext(sc, tsk, signr, set, handler, ctx_has_vsx_region))\
+		goto label;								\
+} while (0)
+static long notrace __unsafe_setup_sigcontext(struct sigcontext __user *sc,
+					struct task_struct *tsk, int signr, sigset_t *set,
+					unsigned long handler, int ctx_has_vsx_region)
 {
 	/* When CONFIG_ALTIVEC is set, we _always_ setup v_regs even if the
 	 * process never used altivec yet (MSR_VEC is zero in pt_regs of
@@ -97,25 +120,22 @@ static long setup_sigcontext(struct sigcontext __user *sc,
 	 */
 #ifdef CONFIG_ALTIVEC
 	elf_vrreg_t __user *v_regs = sigcontext_vmx_regs(sc);
-	unsigned long vrsave;
 #endif
 	struct pt_regs *regs = tsk->thread.regs;
 	unsigned long msr = regs->msr;
-	long err = 0;
 	/* Force usr to alway see softe as 1 (interrupts enabled) */
 	unsigned long softe = 0x1;
 
 	BUG_ON(tsk != current);
 
 #ifdef CONFIG_ALTIVEC
-	err |= __put_user(v_regs, &sc->v_regs);
+	unsafe_put_user(v_regs, &sc->v_regs, efault_out);
 
 	/* save altivec registers */
 	if (tsk->thread.used_vr) {
-		flush_altivec_to_thread(tsk);
 		/* Copy 33 vec registers (vr0..31 and vscr) to the stack */
-		err |= __copy_to_user(v_regs, &tsk->thread.vr_state,
-				      33 * sizeof(vector128));
+		unsafe_copy_to_user(v_regs, &tsk->thread.vr_state,
+				    33 * sizeof(vector128), efault_out);
 		/* set MSR_VEC in the MSR value in the frame to indicate that sc->v_reg)
 		 * contains valid data.
 		 */
@@ -124,19 +144,12 @@ static long setup_sigcontext(struct sigcontext __user *sc,
 	/* We always copy to/from vrsave, it's 0 if we don't have or don't
 	 * use altivec.
 	 */
-	vrsave = 0;
-	if (cpu_has_feature(CPU_FTR_ALTIVEC)) {
-		vrsave = mfspr(SPRN_VRSAVE);
-		tsk->thread.vrsave = vrsave;
-	}
-
-	err |= __put_user(vrsave, (u32 __user *)&v_regs[33]);
+	unsafe_put_user(tsk->thread.vrsave, (u32 __user *)&v_regs[33], efault_out);
 #else /* CONFIG_ALTIVEC */
-	err |= __put_user(0, &sc->v_regs);
+	unsafe_put_user(0, &sc->v_regs, efault_out);
 #endif /* CONFIG_ALTIVEC */
-	flush_fp_to_thread(tsk);
 	/* copy fpr regs and fpscr */
-	err |= copy_fpr_to_user(&sc->fp_regs, tsk);
+	unsafe_copy_fpr_to_user(&sc->fp_regs, tsk, efault_out);
 
 	/*
 	 * Clear the MSR VSX bit to indicate there is no valid state attached
@@ -150,26 +163,27 @@ static long setup_sigcontext(struct sigcontext __user *sc,
 	 * VMX data.
 	 */
 	if (tsk->thread.used_vsr && ctx_has_vsx_region) {
-		flush_vsx_to_thread(tsk);
 		v_regs += ELF_NVRREG;
-		err |= copy_vsx_to_user(v_regs, tsk);
+		unsafe_copy_vsx_to_user(v_regs, tsk, efault_out);
 		/* set MSR_VSX in the MSR value in the frame to
 		 * indicate that sc->vs_reg) contains valid data.
 		 */
 		msr |= MSR_VSX;
 	}
 #endif /* CONFIG_VSX */
-	err |= __put_user(&sc->gp_regs, &sc->regs);
-	WARN_ON(!FULL_REGS(regs));
-	err |= __copy_to_user(&sc->gp_regs, regs, GP_REGS_SIZE);
-	err |= __put_user(msr, &sc->gp_regs[PT_MSR]);
-	err |= __put_user(softe, &sc->gp_regs[PT_SOFTE]);
-	err |= __put_user(signr, &sc->signal);
-	err |= __put_user(handler, &sc->handler);
+	unsafe_put_user(&sc->gp_regs, &sc->regs, efault_out);
+	unsafe_copy_to_user(&sc->gp_regs, regs, GP_REGS_SIZE, efault_out);
+	unsafe_put_user(msr, &sc->gp_regs[PT_MSR], efault_out);
+	unsafe_put_user(softe, &sc->gp_regs[PT_SOFTE], efault_out);
+	unsafe_put_user(signr, &sc->signal, efault_out);
+	unsafe_put_user(handler, &sc->handler, efault_out);
 	if (set != NULL)
-		err |=  __put_user(set->sig[0], &sc->oldmask);
+		unsafe_put_user(set->sig[0], &sc->oldmask, efault_out);
 
-	return err;
+	return 0;
+
+efault_out:
+	return -EFAULT;
 }
 
 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
@@ -294,7 +308,6 @@ static long setup_tm_sigcontexts(struct sigcontext __user *sc,
 
 	err |= __put_user(&sc->gp_regs, &sc->regs);
 	err |= __put_user(&tm_sc->gp_regs, &tm_sc->regs);
-	WARN_ON(!FULL_REGS(regs));
 	err |= __copy_to_user(&tm_sc->gp_regs, regs, GP_REGS_SIZE);
 	err |= __copy_to_user(&sc->gp_regs,
 			      &tsk->thread.ckpt_regs, GP_REGS_SIZE);
@@ -312,14 +325,16 @@ static long setup_tm_sigcontexts(struct sigcontext __user *sc,
 /*
  * Restore the sigcontext from the signal frame.
  */
-
-static long restore_sigcontext(struct task_struct *tsk, sigset_t *set, int sig,
-			      struct sigcontext __user *sc)
+#define unsafe_restore_sigcontext(tsk, set, sig, sc, label) do {	\
+	if (__unsafe_restore_sigcontext(tsk, set, sig, sc))		\
+		goto label;						\
+} while (0)
+static long notrace __unsafe_restore_sigcontext(struct task_struct *tsk, sigset_t *set,
+						int sig, struct sigcontext __user *sc)
 {
 #ifdef CONFIG_ALTIVEC
 	elf_vrreg_t __user *v_regs;
 #endif
-	unsigned long err = 0;
 	unsigned long save_r13 = 0;
 	unsigned long msr;
 	struct pt_regs *regs = tsk->thread.regs;
@@ -334,27 +349,27 @@ static long restore_sigcontext(struct task_struct *tsk, sigset_t *set, int sig,
 		save_r13 = regs->gpr[13];
 
 	/* copy the GPRs */
-	err |= __copy_from_user(regs->gpr, sc->gp_regs, sizeof(regs->gpr));
-	err |= __get_user(regs->nip, &sc->gp_regs[PT_NIP]);
+	unsafe_copy_from_user(regs->gpr, sc->gp_regs, sizeof(regs->gpr), efault_out);
+	unsafe_get_user(regs->nip, &sc->gp_regs[PT_NIP], efault_out);
 	/* get MSR separately, transfer the LE bit if doing signal return */
-	err |= __get_user(msr, &sc->gp_regs[PT_MSR]);
+	unsafe_get_user(msr, &sc->gp_regs[PT_MSR], efault_out);
 	if (sig)
 		regs->msr = (regs->msr & ~MSR_LE) | (msr & MSR_LE);
-	err |= __get_user(regs->orig_gpr3, &sc->gp_regs[PT_ORIG_R3]);
-	err |= __get_user(regs->ctr, &sc->gp_regs[PT_CTR]);
-	err |= __get_user(regs->link, &sc->gp_regs[PT_LNK]);
-	err |= __get_user(regs->xer, &sc->gp_regs[PT_XER]);
-	err |= __get_user(regs->ccr, &sc->gp_regs[PT_CCR]);
+	unsafe_get_user(regs->orig_gpr3, &sc->gp_regs[PT_ORIG_R3], efault_out);
+	unsafe_get_user(regs->ctr, &sc->gp_regs[PT_CTR], efault_out);
+	unsafe_get_user(regs->link, &sc->gp_regs[PT_LNK], efault_out);
+	unsafe_get_user(regs->xer, &sc->gp_regs[PT_XER], efault_out);
+	unsafe_get_user(regs->ccr, &sc->gp_regs[PT_CCR], efault_out);
 	/* Don't allow userspace to set SOFTE */
 	set_trap_norestart(regs);
-	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]);
+	unsafe_get_user(regs->dar, &sc->gp_regs[PT_DAR], efault_out);
+	unsafe_get_user(regs->dsisr, &sc->gp_regs[PT_DSISR], efault_out);
+	unsafe_get_user(regs->result, &sc->gp_regs[PT_RESULT], efault_out);
 
 	if (!sig)
 		regs->gpr[13] = save_r13;
 	if (set != NULL)
-		err |=  __get_user(set->sig[0], &sc->oldmask);
+		unsafe_get_user(set->sig[0], &sc->oldmask, efault_out);
 
 	/*
 	 * Force reload of FP/VEC.
@@ -364,29 +379,27 @@ static long restore_sigcontext(struct task_struct *tsk, sigset_t *set, int sig,
 	regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1 | MSR_VEC | MSR_VSX);
 
 #ifdef CONFIG_ALTIVEC
-	err |= __get_user(v_regs, &sc->v_regs);
-	if (err)
-		return err;
+	unsafe_get_user(v_regs, &sc->v_regs, efault_out);
 	if (v_regs && !access_ok(v_regs, 34 * sizeof(vector128)))
 		return -EFAULT;
 	/* Copy 33 vec registers (vr0..31 and vscr) from the stack */
 	if (v_regs != NULL && (msr & MSR_VEC) != 0) {
-		err |= __copy_from_user(&tsk->thread.vr_state, v_regs,
-					33 * sizeof(vector128));
+		unsafe_copy_from_user(&tsk->thread.vr_state, v_regs,
+				      33 * sizeof(vector128), efault_out);
 		tsk->thread.used_vr = true;
 	} else if (tsk->thread.used_vr) {
 		memset(&tsk->thread.vr_state, 0, 33 * sizeof(vector128));
 	}
 	/* Always get VRSAVE back */
 	if (v_regs != NULL)
-		err |= __get_user(tsk->thread.vrsave, (u32 __user *)&v_regs[33]);
+		unsafe_get_user(tsk->thread.vrsave, (u32 __user *)&v_regs[33], efault_out);
 	else
 		tsk->thread.vrsave = 0;
 	if (cpu_has_feature(CPU_FTR_ALTIVEC))
 		mtspr(SPRN_VRSAVE, tsk->thread.vrsave);
 #endif /* CONFIG_ALTIVEC */
 	/* restore floating point */
-	err |= copy_fpr_from_user(tsk, &sc->fp_regs);
+	unsafe_copy_fpr_from_user(tsk, &sc->fp_regs, efault_out);
 #ifdef CONFIG_VSX
 	/*
 	 * Get additional VSX data. Update v_regs to point after the
@@ -395,14 +408,17 @@ static long restore_sigcontext(struct task_struct *tsk, sigset_t *set, int sig,
 	 */
 	v_regs += ELF_NVRREG;
 	if ((msr & MSR_VSX) != 0) {
-		err |= copy_vsx_from_user(tsk, v_regs);
+		unsafe_copy_vsx_from_user(tsk, v_regs, efault_out);
 		tsk->thread.used_vsr = true;
 	} else {
 		for (i = 0; i < 32 ; i++)
 			tsk->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = 0;
 	}
 #endif
-	return err;
+	return 0;
+
+efault_out:
+	return -EFAULT;
 }
 
 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
@@ -586,6 +602,12 @@ static long restore_tm_sigcontexts(struct task_struct *tsk,
 
 	return err;
 }
+#else /* !CONFIG_PPC_TRANSACTIONAL_MEM */
+static long restore_tm_sigcontexts(struct task_struct *tsk, struct sigcontext __user *sc,
+				   struct sigcontext __user *tm_sc)
+{
+	return -EINVAL;
+}
 #endif
 
 /*
@@ -655,12 +677,16 @@ SYSCALL_DEFINE3(swapcontext, struct ucontext __user *, old_ctx,
 		ctx_has_vsx_region = 1;
 
 	if (old_ctx != NULL) {
-		if (!access_ok(old_ctx, ctx_size)
-		    || setup_sigcontext(&old_ctx->uc_mcontext, current, 0, NULL, 0,
-					ctx_has_vsx_region)
-		    || __copy_to_user(&old_ctx->uc_sigmask,
-				      &current->blocked, sizeof(sigset_t)))
+		prepare_setup_sigcontext(current);
+		if (!user_write_access_begin(old_ctx, ctx_size))
 			return -EFAULT;
+
+		unsafe_setup_sigcontext(&old_ctx->uc_mcontext, current, 0, NULL,
+					0, ctx_has_vsx_region, efault_out);
+		unsafe_copy_to_user(&old_ctx->uc_sigmask, &current->blocked,
+				    sizeof(sigset_t), efault_out);
+
+		user_write_access_end();
 	}
 	if (new_ctx == NULL)
 		return 0;
@@ -680,15 +706,25 @@ SYSCALL_DEFINE3(swapcontext, struct ucontext __user *, old_ctx,
 	 * We kill the task with a SIGSEGV in this situation.
 	 */
 
-	if (__copy_from_user(&set, &new_ctx->uc_sigmask, sizeof(set)))
+	if (__get_user_sigset(&set, &new_ctx->uc_sigmask))
 		do_exit(SIGSEGV);
 	set_current_blocked(&set);
-	if (restore_sigcontext(current, NULL, 0, &new_ctx->uc_mcontext))
+
+	if (!user_read_access_begin(new_ctx, ctx_size))
+		return -EFAULT;
+	if (__unsafe_restore_sigcontext(current, NULL, 0, &new_ctx->uc_mcontext)) {
+		user_read_access_end();
 		do_exit(SIGSEGV);
+	}
+	user_read_access_end();
 
 	/* This returns like rt_sigreturn */
 	set_thread_flag(TIF_RESTOREALL);
 	return 0;
+
+efault_out:
+	user_write_access_end();
+	return -EFAULT;
 }
 
 
@@ -701,9 +737,7 @@ SYSCALL_DEFINE0(rt_sigreturn)
 	struct pt_regs *regs = current_pt_regs();
 	struct ucontext __user *uc = (struct ucontext __user *)regs->gpr[1];
 	sigset_t set;
-#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
 	unsigned long msr;
-#endif
 
 	/* Always make any pending restarted system calls return -EINTR */
 	current->restart_block.fn = do_no_restart_syscall;
@@ -711,52 +745,54 @@ SYSCALL_DEFINE0(rt_sigreturn)
 	if (!access_ok(uc, sizeof(*uc)))
 		goto badframe;
 
-	if (__copy_from_user(&set, &uc->uc_sigmask, sizeof(set)))
+	if (__get_user_sigset(&set, &uc->uc_sigmask))
 		goto badframe;
 	set_current_blocked(&set);
 
-#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
-	/*
-	 * If there is a transactional state then throw it away.
-	 * The purpose of a sigreturn is to destroy all traces of the
-	 * signal frame, this includes any transactional state created
-	 * within in. We only check for suspended as we can never be
-	 * active in the kernel, we are active, there is nothing better to
-	 * do than go ahead and Bad Thing later.
-	 * The cause is not important as there will never be a
-	 * recheckpoint so it's not user visible.
-	 */
-	if (MSR_TM_SUSPENDED(mfmsr()))
-		tm_reclaim_current(0);
+	if (IS_ENABLED(CONFIG_PPC_TRANSACTIONAL_MEM)) {
+		/*
+		 * If there is a transactional state then throw it away.
+		 * The purpose of a sigreturn is to destroy all traces of the
+		 * signal frame, this includes any transactional state created
+		 * within in. We only check for suspended as we can never be
+		 * active in the kernel, we are active, there is nothing better to
+		 * do than go ahead and Bad Thing later.
+		 * The cause is not important as there will never be a
+		 * recheckpoint so it's not user visible.
+		 */
+		if (MSR_TM_SUSPENDED(mfmsr()))
+			tm_reclaim_current(0);
 
-	/*
-	 * Disable MSR[TS] bit also, so, if there is an exception in the
-	 * code below (as a page fault in copy_ckvsx_to_user()), it does
-	 * not recheckpoint this task if there was a context switch inside
-	 * the exception.
-	 *
-	 * A major page fault can indirectly call schedule(). A reschedule
-	 * process in the middle of an exception can have a side effect
-	 * (Changing the CPU MSR[TS] state), since schedule() is called
-	 * with the CPU MSR[TS] disable and returns with MSR[TS]=Suspended
-	 * (switch_to() calls tm_recheckpoint() for the 'new' process). In
-	 * this case, the process continues to be the same in the CPU, but
-	 * the CPU state just changed.
-	 *
-	 * This can cause a TM Bad Thing, since the MSR in the stack will
-	 * have the MSR[TS]=0, and this is what will be used to RFID.
-	 *
-	 * Clearing MSR[TS] state here will avoid a recheckpoint if there
-	 * is any process reschedule in kernel space. The MSR[TS] state
-	 * does not need to be saved also, since it will be replaced with
-	 * the MSR[TS] that came from user context later, at
-	 * restore_tm_sigcontexts.
-	 */
-	regs->msr &= ~MSR_TS_MASK;
+		/*
+		 * Disable MSR[TS] bit also, so, if there is an exception in the
+		 * code below (as a page fault in copy_ckvsx_to_user()), it does
+		 * not recheckpoint this task if there was a context switch inside
+		 * the exception.
+		 *
+		 * A major page fault can indirectly call schedule(). A reschedule
+		 * process in the middle of an exception can have a side effect
+		 * (Changing the CPU MSR[TS] state), since schedule() is called
+		 * with the CPU MSR[TS] disable and returns with MSR[TS]=Suspended
+		 * (switch_to() calls tm_recheckpoint() for the 'new' process). In
+		 * this case, the process continues to be the same in the CPU, but
+		 * the CPU state just changed.
+		 *
+		 * This can cause a TM Bad Thing, since the MSR in the stack will
+		 * have the MSR[TS]=0, and this is what will be used to RFID.
+		 *
+		 * Clearing MSR[TS] state here will avoid a recheckpoint if there
+		 * is any process reschedule in kernel space. The MSR[TS] state
+		 * does not need to be saved also, since it will be replaced with
+		 * the MSR[TS] that came from user context later, at
+		 * restore_tm_sigcontexts.
+		 */
+		regs->msr &= ~MSR_TS_MASK;
 
-	if (__get_user(msr, &uc->uc_mcontext.gp_regs[PT_MSR]))
-		goto badframe;
-	if (MSR_TM_ACTIVE(msr)) {
+		if (__get_user(msr, &uc->uc_mcontext.gp_regs[PT_MSR]))
+			goto badframe;
+	}
+
+	if (IS_ENABLED(CONFIG_PPC_TRANSACTIONAL_MEM) && MSR_TM_ACTIVE(msr)) {
 		/* We recheckpoint on return. */
 		struct ucontext __user *uc_transact;
 
@@ -769,9 +805,7 @@ SYSCALL_DEFINE0(rt_sigreturn)
 		if (restore_tm_sigcontexts(current, &uc->uc_mcontext,
 					   &uc_transact->uc_mcontext))
 			goto badframe;
-	} else
-#endif
-	{
+	} else {
 		/*
 		 * Fall through, for non-TM restore
 		 *
@@ -785,8 +819,13 @@ SYSCALL_DEFINE0(rt_sigreturn)
 		 * causing a TM bad thing.
 		 */
 		current->thread.regs->msr &= ~MSR_TS_MASK;
-		if (restore_sigcontext(current, NULL, 1, &uc->uc_mcontext))
+		if (!user_read_access_begin(&uc->uc_mcontext, sizeof(uc->uc_mcontext)))
 			goto badframe;
+
+		unsafe_restore_sigcontext(current, NULL, 1, &uc->uc_mcontext,
+					  badframe_block);
+
+		user_read_access_end();
 	}
 
 	if (restore_altstack(&uc->uc_stack))
@@ -795,6 +834,8 @@ SYSCALL_DEFINE0(rt_sigreturn)
 	set_thread_flag(TIF_RESTOREALL);
 	return 0;
 
+badframe_block:
+	user_read_access_end();
 badframe:
 	signal_fault(current, regs, "rt_sigreturn", uc);
 
@@ -809,46 +850,57 @@ int handle_rt_signal64(struct ksignal *ksig, sigset_t *set,
 	unsigned long newsp = 0;
 	long err = 0;
 	struct pt_regs *regs = tsk->thread.regs;
-#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
 	/* Save the thread's msr before get_tm_stackpointer() changes it */
 	unsigned long msr = regs->msr;
-#endif
 
 	frame = get_sigframe(ksig, tsk, sizeof(*frame), 0);
-	if (!access_ok(frame, sizeof(*frame)))
-		goto badframe;
 
-	err |= __put_user(&frame->info, &frame->pinfo);
-	err |= __put_user(&frame->uc, &frame->puc);
-	err |= copy_siginfo_to_user(&frame->info, &ksig->info);
-	if (err)
+	/*
+	 * This only applies when calling unsafe_setup_sigcontext() and must be
+	 * called before opening the uaccess window.
+	 */
+	if (!MSR_TM_ACTIVE(msr))
+		prepare_setup_sigcontext(tsk);
+
+	if (!user_write_access_begin(frame, sizeof(*frame)))
 		goto badframe;
 
+	unsafe_put_user(&frame->info, &frame->pinfo, badframe_block);
+	unsafe_put_user(&frame->uc, &frame->puc, badframe_block);
+
 	/* Create the ucontext.  */
-	err |= __put_user(0, &frame->uc.uc_flags);
-	err |= __save_altstack(&frame->uc.uc_stack, regs->gpr[1]);
-#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+	unsafe_put_user(0, &frame->uc.uc_flags, badframe_block);
+	unsafe_save_altstack(&frame->uc.uc_stack, regs->gpr[1], badframe_block);
+
 	if (MSR_TM_ACTIVE(msr)) {
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
 		/* The ucontext_t passed to userland points to the second
 		 * ucontext_t (for transactional state) with its uc_link ptr.
 		 */
-		err |= __put_user(&frame->uc_transact, &frame->uc.uc_link);
+		unsafe_put_user(&frame->uc_transact, &frame->uc.uc_link, badframe_block);
+
+		user_write_access_end();
+
 		err |= setup_tm_sigcontexts(&frame->uc.uc_mcontext,
 					    &frame->uc_transact.uc_mcontext,
 					    tsk, ksig->sig, NULL,
 					    (unsigned long)ksig->ka.sa.sa_handler,
 					    msr);
-	} else
+
+		if (!user_write_access_begin(&frame->uc.uc_sigmask,
+					     sizeof(frame->uc.uc_sigmask)))
+			goto badframe;
+
 #endif
-	{
-		err |= __put_user(0, &frame->uc.uc_link);
-		err |= setup_sigcontext(&frame->uc.uc_mcontext, tsk, ksig->sig,
+	} else {
+		unsafe_put_user(0, &frame->uc.uc_link, badframe_block);
+		unsafe_setup_sigcontext(&frame->uc.uc_mcontext, tsk, ksig->sig,
 					NULL, (unsigned long)ksig->ka.sa.sa_handler,
-					1);
+					1, badframe_block);
 	}
-	err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
-	if (err)
-		goto badframe;
+
+	unsafe_copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set), badframe_block);
+	user_write_access_end();
 
 	/* Make sure signal handler doesn't get spurious FP exceptions */
 	tsk->thread.fp_state.fpscr = 0;
@@ -863,6 +915,11 @@ int handle_rt_signal64(struct ksignal *ksig, sigset_t *set,
 		regs->nip = (unsigned long) &frame->tramp[0];
 	}
 
+
+	/* Save the siginfo outside of the unsafe block. */
+	if (copy_siginfo_to_user(&frame->info, &ksig->info))
+		goto badframe;
+
 	/* Allocate a dummy caller frame for the signal handler. */
 	newsp = ((unsigned long)frame) - __SIGNAL_FRAMESIZE;
 	err |= put_user(regs->gpr[1], (unsigned long __user *)newsp);
@@ -902,6 +959,8 @@ int handle_rt_signal64(struct ksignal *ksig, sigset_t *set,
 
 	return 0;
 
+badframe_block:
+	user_write_access_end();
 badframe:
 	signal_fault(current, regs, "handle_rt_signal64", frame);