--- zzzz-none-000/linux-3.10.107/arch/sparc/kernel/signal_32.c	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/arch/sparc/kernel/signal_32.c	2021-02-04 17:41:59.000000000 +0000
@@ -28,6 +28,7 @@
 #include <asm/switch_to.h>
 
 #include "sigutil.h"
+#include "kernel.h"
 
 extern void fpsave(unsigned long *fpregs, unsigned long *fsr,
 		   void *fpqueue, unsigned long *fpqdepth);
@@ -59,27 +60,42 @@
 #define SF_ALIGNEDSZ  (((sizeof(struct signal_frame) + 7) & (~7)))
 #define RT_ALIGNEDSZ  (((sizeof(struct rt_signal_frame) + 7) & (~7)))
 
+/* Checks if the fp is valid.  We always build signal frames which are
+ * 16-byte aligned, therefore we can always enforce that the restore
+ * frame has that property as well.
+ */
+static inline bool invalid_frame_pointer(void __user *fp, int fplen)
+{
+	if ((((unsigned long) fp) & 15) || !__access_ok((unsigned long)fp, fplen))
+		return true;
+
+	return false;
+}
+
 asmlinkage void do_sigreturn(struct pt_regs *regs)
 {
+	unsigned long up_psr, pc, npc, ufp;
 	struct signal_frame __user *sf;
-	unsigned long up_psr, pc, npc;
 	sigset_t set;
 	__siginfo_fpu_t __user *fpu_save;
 	__siginfo_rwin_t __user *rwin_save;
 	int err;
 
 	/* Always make any pending restarted system calls return -EINTR */
-	current_thread_info()->restart_block.fn = do_no_restart_syscall;
+	current->restart_block.fn = do_no_restart_syscall;
 
 	synchronize_user_stack();
 
 	sf = (struct signal_frame __user *) regs->u_regs[UREG_FP];
 
 	/* 1. Make sure we are not getting garbage from the user */
-	if (!access_ok(VERIFY_READ, sf, sizeof(*sf)))
+	if (invalid_frame_pointer(sf, sizeof(*sf)))
 		goto segv_and_exit;
 
-	if (((unsigned long) sf) & 3)
+	if (get_user(ufp, &sf->info.si_regs.u_regs[UREG_FP]))
+		goto segv_and_exit;
+
+	if (ufp & 0x7)
 		goto segv_and_exit;
 
 	err = __get_user(pc,  &sf->info.si_regs.pc);
@@ -126,7 +142,7 @@
 asmlinkage void do_rt_sigreturn(struct pt_regs *regs)
 {
 	struct rt_signal_frame __user *sf;
-	unsigned int psr, pc, npc;
+	unsigned int psr, pc, npc, ufp;
 	__siginfo_fpu_t __user *fpu_save;
 	__siginfo_rwin_t __user *rwin_save;
 	sigset_t set;
@@ -134,8 +150,13 @@
 
 	synchronize_user_stack();
 	sf = (struct rt_signal_frame __user *) regs->u_regs[UREG_FP];
-	if (!access_ok(VERIFY_READ, sf, sizeof(*sf)) ||
-	    (((unsigned long) sf) & 0x03))
+	if (invalid_frame_pointer(sf, sizeof(*sf)))
+		goto segv;
+
+	if (get_user(ufp, &sf->regs.u_regs[UREG_FP]))
+		goto segv;
+
+	if (ufp & 0x7)
 		goto segv;
 
 	err = __get_user(pc, &sf->regs.pc);
@@ -177,15 +198,6 @@
 	force_sig(SIGSEGV, current);
 }
 
-/* Checks if the fp is valid */
-static inline int invalid_frame_pointer(void __user *fp, int fplen)
-{
-	if ((((unsigned long) fp) & 7) || !__access_ok((unsigned long)fp, fplen))
-		return 1;
-
-	return 0;
-}
-
 static inline void __user *get_sigframe(struct ksignal *ksig, struct pt_regs *regs, unsigned long framesize)
 {
 	unsigned long sp = regs->u_regs[UREG_FP];
@@ -341,7 +353,7 @@
 	err |= __put_user(0, &sf->extra_size);
 
 	if (psr & PSR_EF) {
-		__siginfo_fpu_t *fp = tail;
+		__siginfo_fpu_t __user *fp = tail;
 		tail += sizeof(*fp);
 		err |= save_fpu_state(regs, fp);
 		err |= __put_user(fp, &sf->fpu_save);
@@ -349,7 +361,7 @@
 		err |= __put_user(0, &sf->fpu_save);
 	}
 	if (wsaved) {
-		__siginfo_rwin_t *rwp = tail;
+		__siginfo_rwin_t __user *rwp = tail;
 		tail += sizeof(*rwp);
 		err |= save_rwin_state(wsaved, rwp);
 		err |= __put_user(rwp, &sf->rwin_save);
@@ -517,9 +529,9 @@
 	}
 }
 
-asmlinkage int
-do_sys_sigstack(struct sigstack __user *ssptr, struct sigstack __user *ossptr,
-		unsigned long sp)
+asmlinkage int do_sys_sigstack(struct sigstack __user *ssptr,
+                               struct sigstack __user *ossptr,
+                               unsigned long sp)
 {
 	int ret = -EFAULT;