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>

diff --git a/arch/arm/kernel/ptrace.c b/arch/arm/kernel/ptrace.c
index 19c6816..b13e70f 100644 (file)
--- 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: