[POWERPC] user_regset PTRACE_SETREGS regression fix

The PTRACE_SETREGS request was only recently added on powerpc,
and gdb does not use it.  So it slipped through without getting
all the testing it should have had.

The user_regset changes had a simple bug in storing to all of
the 32-bit general registers block on 64-bit kernels.  This bug
only comes up with PTRACE_SETREGS, not PPC_PTRACE_SETREGS.
It causes a BUG_ON to hit, so this fix needs to go in ASAP.

Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

diff --git a/arch/powerpc/kernel/ptrace.c b/arch/powerpc/kernel/ptrace.c
index 7673e98657330dd7f90dd4d29f569d4ea2ca10e8..2a9fe97e452129c9cd843e8e404d327df8605f66 100644 (file)
--- a/arch/powerpc/kernel/ptrace.c
+++ b/arch/powerpc/kernel/ptrace.c
@@ -530,15 +530,21 @@ static int gpr32_set(struct task_struct *target,
                --count;
        }
 
-       if (kbuf)
+       if (kbuf) {
                for (; count > 0 && pos <= PT_MAX_PUT_REG; --count)
                        regs[pos++] = *k++;
-       else
+               for (; count > 0 && pos < PT_TRAP; --count, ++pos)
+                       ++k;
+       } else {
                for (; count > 0 && pos <= PT_MAX_PUT_REG; --count) {
                        if (__get_user(reg, u++))
                                return -EFAULT;
                        regs[pos++] = reg;
                }
+               for (; count > 0 && pos < PT_TRAP; --count, ++pos)
+                       if (__get_user(reg, u++))
+                               return -EFAULT;
+       }
 
        if (count > 0 && pos == PT_TRAP) {
                if (kbuf)