x86/ptrace: Fix regs_get_argument_nth() to add correct offset

Fix regs_get_argument_nth() to add correct offset bytes. Because
offset_of() returns offset in byte, the offset should be added
to char * instead of unsigned long *.

Signed-off-by: Masami Hiramatsu <[email protected]>
Acked-by: Steven Rostedt <[email protected]>
Cc: Jim Keniston <[email protected]>
Cc: Ananth N Mavinakayanahalli <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: Frank Ch. Eigler <[email protected]>
Cc: Frederic Weisbecker <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jason Baron <[email protected]>
Cc: K.Prasad <[email protected]>
Cc: Lai Jiangshan <[email protected]>
Cc: Li Zefan <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Srikar Dronamraju <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Tom Zanussi <[email protected]>
LKML-Reference: <[email protected]>
Signed-off-by: Frederic Weisbecker <[email protected]>

1 files changed, 1 insertions, 1 deletions

diff --git a/arch/x86/kernel/ptrace.c b/arch/x86/kernel/ptrace.c
index a33a17d5d5c8..caffb6809452 100644
--- a/arch/x86/kernel/ptrace.c
+++ b/arch/x86/kernel/ptrace.c
@@ -150,7 +150,7 @@ static const int arg_offs_table[] = {
 unsigned long regs_get_argument_nth(struct pt_regs *regs, unsigned int n)
 {
 	if (n < ARRAY_SIZE(arg_offs_table))
-		return *((unsigned long *)regs + arg_offs_table[n]);
+		return *(unsigned long *)((char *)regs + arg_offs_table[n]);
 	else {
 		/*
 		 * The typical case: arg n is on the stack.