m68k: Move signal frame following exception on 68020/030

[linux-stable] / arch / m68k / kernel / signal.c

diff --git a/arch/m68k/kernel/signal.c b/arch/m68k/kernel/signal.c
index f7121b775e5f0147bf9acbaf344b5761a680a94f..ab5fec67e541c2827fc43149549a0b96c716bf6f 100644 (file)
--- a/arch/m68k/kernel/signal.c
+++ b/arch/m68k/kernel/signal.c
@@ -883,11 +883,17 @@ static inline int rt_setup_ucontext(struct ucontext __user *uc, struct pt_regs *
 }
 
 static inline void __user *
-get_sigframe(struct ksignal *ksig, size_t frame_size)
+get_sigframe(struct ksignal *ksig, struct pt_regs *tregs, size_t frame_size)
 {
        unsigned long usp = sigsp(rdusp(), ksig);
+       unsigned long gap = 0;
 
-       return (void __user *)((usp - frame_size) & -8UL);
+       if (CPU_IS_020_OR_030 && tregs->format == 0xb) {
+               /* USP is unreliable so use worst-case value */
+               gap = 256;
+       }
+
+       return (void __user *)((usp - gap - frame_size) & -8UL);
 }
 
 static int setup_frame(struct ksignal *ksig, sigset_t *set,
@@ -905,7 +911,7 @@ static int setup_frame(struct ksignal *ksig, sigset_t *set,
                return -EFAULT;
        }
 
-       frame = get_sigframe(ksig, sizeof(*frame) + fsize);
+       frame = get_sigframe(ksig, tregs, sizeof(*frame) + fsize);
 
        if (fsize)
                err |= copy_to_user (frame + 1, regs + 1, fsize);
@@ -976,7 +982,7 @@ static int setup_rt_frame(struct ksignal *ksig, sigset_t *set,
                return -EFAULT;
        }
 
-       frame = get_sigframe(ksig, sizeof(*frame));
+       frame = get_sigframe(ksig, tregs, sizeof(*frame));
 
        if (fsize)
                err |= copy_to_user (&frame->uc.uc_extra, regs + 1, fsize);