When kernel is compiled with CONFIG_HAVE_HW_BREAKPOINT=N, user can
still create watchpoint using PPC_PTRACE_SETHWDEBUG, with limited
functionalities. But, such watchpoints are never firing because of
the missing privilege settings. Fix that.

It's safe to set HW_BRK_TYPE_PRIV_ALL because we don't really leak
any kernel address in signal info. Setting HW_BRK_TYPE_PRIV_ALL will
also help to find scenarios when kernel corrupts user memory.

Reported-by: Pedro Miraglia Franco de Carvalho <pedro...@linux.ibm.com>
Suggested-by: Pedro Miraglia Franco de Carvalho <pedro...@linux.ibm.com>
Signed-off-by: Ravi Bangoria <ravi.bango...@linux.ibm.com>
---
 arch/powerpc/kernel/ptrace/ptrace-noadv.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/powerpc/kernel/ptrace/ptrace-noadv.c 
b/arch/powerpc/kernel/ptrace/ptrace-noadv.c
index 697c7e4b5877..57a0ab822334 100644
--- a/arch/powerpc/kernel/ptrace/ptrace-noadv.c
+++ b/arch/powerpc/kernel/ptrace/ptrace-noadv.c
@@ -217,7 +217,7 @@ long ppc_set_hwdebug(struct task_struct *child, struct 
ppc_hw_breakpoint *bp_inf
                return -EIO;
 
        brk.address = ALIGN_DOWN(bp_info->addr, HW_BREAKPOINT_SIZE);
-       brk.type = HW_BRK_TYPE_TRANSLATE;
+       brk.type = HW_BRK_TYPE_TRANSLATE | HW_BRK_TYPE_PRIV_ALL;
        brk.len = DABR_MAX_LEN;
        if (bp_info->trigger_type & PPC_BREAKPOINT_TRIGGER_READ)
                brk.type |= HW_BRK_TYPE_READ;
-- 
2.26.2

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