linux-kernel - [PATCH 3.16 111/202] c6x: Use get_signal() signal_setup

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Message-ID: <lsq.1556377989.513261021@decadent.org.uk>
Date:   Sat, 27 Apr 2019 16:13:09 +0100
From:   Ben Hutchings <ben@...adent.org.uk>
To:     linux-kernel@...r.kernel.org, stable@...r.kernel.org
CC:     akpm@...ux-foundation.org, Denis Kirjanov <kda@...ux-powerpc.org>,
        "Mark Salter" <msalter@...hat.com>,
        "Richard Weinberger" <richard@....at>
Subject: [PATCH 3.16 111/202] c6x: Use get_signal() signal_setup_done()

3.16.66-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Richard Weinberger <richard@....at>

commit e19c025bc9a184ed9c5daf06ffb89abc81d1696a upstream.

Use the more generic functions get_signal() signal_setup_done()
for signal delivery.

Tested-by: Mark Salter <msalter@...hat.com>
Acked-by: Mark Salter <msalter@...hat.com>
Signed-off-by: Richard Weinberger <richard@....at>
[bwh: Backported to 3.16 as dependency of commit 35634ffa1751
 "signal: Always notice exiting tasks"]
Signed-off-by: Ben Hutchings <ben@...adent.org.uk>
---
 arch/c6x/kernel/signal.c | 43 +++++++++++++++++-----------------------
 1 file changed, 18 insertions(+), 25 deletions(-)

--- a/arch/c6x/kernel/signal.c
+++ b/arch/c6x/kernel/signal.c
@@ -146,21 +146,21 @@ static inline void __user *get_sigframe(
 	return (void __user *)((sp - framesize) & ~7);
 }
 
-static int setup_rt_frame(int signr, struct k_sigaction *ka, siginfo_t *info,
-			   sigset_t *set, struct pt_regs *regs)
+static int setup_rt_frame(struct ksignal *ksig, sigset_t *set,
+			  struct pt_regs *regs)
 {
 	struct rt_sigframe __user *frame;
 	unsigned long __user *retcode;
 	int err = 0;
 
-	frame = get_sigframe(ka, regs, sizeof(*frame));
+	frame = get_sigframe(&ksig->ka, regs, sizeof(*frame));
 
 	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
-		goto segv_and_exit;
+		return -EFAULT;
 
 	err |= __put_user(&frame->info, &frame->pinfo);
 	err |= __put_user(&frame->uc, &frame->puc);
-	err |= copy_siginfo_to_user(&frame->info, info);
+	err |= copy_siginfo_to_user(&frame->info, &ksig->info);
 
 	/* Clear all the bits of the ucontext we don't use.  */
 	err |= __clear_user(&frame->uc, offsetof(struct ucontext, uc_mcontext));
@@ -188,7 +188,7 @@ static int setup_rt_frame(int signr, str
 #undef COPY
 
 	if (err)
-		goto segv_and_exit;
+		return -EFAULT;
 
 	flush_icache_range((unsigned long) &frame->retcode,
 			   (unsigned long) &frame->retcode + RETCODE_SIZE);
@@ -198,10 +198,10 @@ static int setup_rt_frame(int signr, str
 	/* Change user context to branch to signal handler */
 	regs->sp = (unsigned long) frame - 8;
 	regs->b3 = (unsigned long) retcode;
-	regs->pc = (unsigned long) ka->sa.sa_handler;
+	regs->pc = (unsigned long) ksig->ka.sa.sa_handler;
 
 	/* Give the signal number to the handler */
-	regs->a4 = signr;
+	regs->a4 = ksig->sig;
 
 	/*
 	 * For realtime signals we must also set the second and third
@@ -212,10 +212,6 @@ static int setup_rt_frame(int signr, str
 	regs->a6 = (unsigned long)&frame->uc;
 
 	return 0;
-
-segv_and_exit:
-	force_sigsegv(signr, current);
-	return -EFAULT;
 }
 
 static inline void
@@ -245,10 +241,11 @@ do_restart:
 /*
  * handle the actual delivery of a signal to userspace
  */
-static void handle_signal(int sig,
-			 siginfo_t *info, struct k_sigaction *ka,
-			 struct pt_regs *regs, int syscall)
+static void handle_signal(struct ksignal *ksig, struct pt_regs *regs,
+			  int syscall)
 {
+	int ret;
+
 	/* Are we from a system call? */
 	if (syscall) {
 		/* If so, check system call restarting.. */
@@ -259,7 +256,7 @@ static void handle_signal(int sig,
 			break;
 
 		case -ERESTARTSYS:
-			if (!(ka->sa.sa_flags & SA_RESTART)) {
+			if (!(ksig->ka.sa.sa_flags & SA_RESTART)) {
 				regs->a4 = -EINTR;
 				break;
 			}
@@ -272,9 +269,8 @@ static void handle_signal(int sig,
 	}
 
 	/* Set up the stack frame */
-	if (setup_rt_frame(sig, ka, info, sigmask_to_save(), regs) < 0)
-		return;
-	signal_delivered(sig, info, ka, regs, 0);
+	ret = setup_rt_frame(ksig, sigmask_to_save(), regs);
+	signal_setup_done(ret, ksig, 0);
 }
 
 /*
@@ -282,18 +278,15 @@ static void handle_signal(int sig,
  */
 static void do_signal(struct pt_regs *regs, int syscall)
 {
-	struct k_sigaction ka;
-	siginfo_t info;
-	int signr;
+	struct ksignal ksig;
 
 	/* we want the common case to go fast, which is why we may in certain
 	 * cases get here from kernel mode */
 	if (!user_mode(regs))
 		return;
 
-	signr = get_signal_to_deliver(&info, &ka, regs, NULL);
-	if (signr > 0) {
-		handle_signal(signr, &info, &ka, regs, syscall);
+	if (get_signal(&ksig)) {
+		handle_signal(&ksig, regs, syscall);
 		return;
 	}