Upgrade to 4.4.50-rt62

[kvmfornfv.git] / kernel / arch / sparc / kernel / signal_64.c

diff --git a/kernel/arch/sparc/kernel/signal_64.c b/kernel/arch/sparc/kernel/signal_64.c
index d88beff..5ee930c 100644 (file)
--- a/kernel/arch/sparc/kernel/signal_64.c
+++ b/kernel/arch/sparc/kernel/signal_64.c
@@ -52,7 +52,7 @@ asmlinkage void sparc64_set_context(struct pt_regs *regs)
        unsigned char fenab;
        int err;
 
-       flush_user_windows();
+       synchronize_user_stack();
        if (get_thread_wsaved()                                 ||
            (((unsigned long)ucp) & (sizeof(unsigned long)-1))  ||
            (!__access_ok(ucp, sizeof(*ucp))))
@@ -234,6 +234,17 @@ do_sigsegv:
        goto out;
 }
 
+/* Checks if the fp is valid.  We always build rt signal frames which
+ * are 16-byte aligned, therefore we can always enforce that the
+ * restore frame has that property as well.
+ */
+static bool invalid_frame_pointer(void __user *fp)
+{
+       if (((unsigned long) fp) & 15)
+               return true;
+       return false;
+}
+
 struct rt_signal_frame {
        struct sparc_stackf     ss;
        siginfo_t               info;
@@ -246,8 +257,8 @@ struct rt_signal_frame {
 
 void do_rt_sigreturn(struct pt_regs *regs)
 {
+       unsigned long tpc, tnpc, tstate, ufp;
        struct rt_signal_frame __user *sf;
-       unsigned long tpc, tnpc, tstate;
        __siginfo_fpu_t __user *fpu_save;
        __siginfo_rwin_t __user *rwin_save;
        sigset_t set;
@@ -261,10 +272,16 @@ void do_rt_sigreturn(struct pt_regs *regs)
                (regs->u_regs [UREG_FP] + STACK_BIAS);
 
        /* 1. Make sure we are not getting garbage from the user */
-       if (((unsigned long) sf) & 3)
+       if (invalid_frame_pointer(sf))
+               goto segv;
+
+       if (get_user(ufp, &sf->regs.u_regs[UREG_FP]))
                goto segv;
 
-       err = get_user(tpc, &sf->regs.tpc);
+       if ((ufp + STACK_BIAS) & 0x7)
+               goto segv;
+
+       err = __get_user(tpc, &sf->regs.tpc);
        err |= __get_user(tnpc, &sf->regs.tnpc);
        if (test_thread_flag(TIF_32BIT)) {
                tpc &= 0xffffffff;
@@ -308,14 +325,6 @@ segv:
        force_sig(SIGSEGV, current);
 }
 
-/* Checks if the fp is valid */
-static int invalid_frame_pointer(void __user *fp)
-{
-       if (((unsigned long) fp) & 15)
-               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] + STACK_BIAS;