ARM: 6767/1: ptrace: fix register indexing in GETHBPREGS request

The GETHBPREGS ptrace request incorrectly maps its index argument onto
the thread's saved debug state when the index != 0. This has not yet
been seen from userspace because GDB (the only user of this request)
only reads from register 0.

This patch fixes the indexing.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 3 insertions, 3 deletions

diff --git a/arch/arm/kernel/ptrace.c b/arch/arm/kernel/ptrace.c
index 19c6816db61e..b13e70f63d71 100644
--- a/arch/arm/kernel/ptrace.c
+++ b/arch/arm/kernel/ptrace.c
@@ -996,10 +996,10 @@ static int ptrace_gethbpregs(struct task_struct *tsk, long num,
                 while (!(arch_ctrl.len & 0x1))
                         arch_ctrl.len >>= 1;
 
-                if (idx & 0x1)
-                        reg = encode_ctrl_reg(arch_ctrl);
-                else
+                if (num & 0x1)
                         reg = bp->attr.bp_addr;
+                else
+                        reg = encode_ctrl_reg(arch_ctrl);
         }
 
 put: