[PATCH 2/3] powerpc/ptrace: Don't use sizeof(struct pt_regs) in ptrace code

Michael Ellerman mpe at ellerman.id.au
Sat Oct 13 21:56:45 AEDT 2018


Now that we've split the user & kernel versions of pt_regs we need to
be more careful in the ptrace code.

For now we've ensured the location of the fields in both structs is
the same, so most of the ptrace code doesn't need updating.

But there are a few places where we use sizeof(pt_regs), and these
will be wrong as soon as we increase the size of the kernel structure.

So flip them all to use sizeof(user_pt_regs).

Signed-off-by: Michael Ellerman <mpe at ellerman.id.au>
---
 arch/powerpc/kernel/ptrace.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/arch/powerpc/kernel/ptrace.c b/arch/powerpc/kernel/ptrace.c
index 939d7f81bbbe..c7d0d0c1e34d 100644
--- a/arch/powerpc/kernel/ptrace.c
+++ b/arch/powerpc/kernel/ptrace.c
@@ -297,7 +297,7 @@ int ptrace_get_reg(struct task_struct *task, int regno, unsigned long *data)
 	}
 #endif
 
-	if (regno < (sizeof(struct pt_regs) / sizeof(unsigned long))) {
+	if (regno < (sizeof(struct user_pt_regs) / sizeof(unsigned long))) {
 		*data = ((unsigned long *)task->thread.regs)[regno];
 		return 0;
 	}
@@ -360,10 +360,10 @@ static int gpr_get(struct task_struct *target, const struct user_regset *regset,
 		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
 					  &target->thread.regs->orig_gpr3,
 					  offsetof(struct pt_regs, orig_gpr3),
-					  sizeof(struct pt_regs));
+					  sizeof(struct user_pt_regs));
 	if (!ret)
 		ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
-					       sizeof(struct pt_regs), -1);
+					       sizeof(struct user_pt_regs), -1);
 
 	return ret;
 }
@@ -853,10 +853,10 @@ static int tm_cgpr_get(struct task_struct *target,
 		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
 					  &target->thread.ckpt_regs.orig_gpr3,
 					  offsetof(struct pt_regs, orig_gpr3),
-					  sizeof(struct pt_regs));
+					  sizeof(struct user_pt_regs));
 	if (!ret)
 		ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
-					       sizeof(struct pt_regs), -1);
+					       sizeof(struct user_pt_regs), -1);
 
 	return ret;
 }
@@ -3131,7 +3131,7 @@ long arch_ptrace(struct task_struct *child, long request,
 	case PTRACE_GETREGS:	/* Get all pt_regs from the child. */
 		return copy_regset_to_user(child, &user_ppc_native_view,
 					   REGSET_GPR,
-					   0, sizeof(struct pt_regs),
+					   0, sizeof(struct user_pt_regs),
 					   datavp);
 
 #ifdef CONFIG_PPC64
@@ -3140,7 +3140,7 @@ long arch_ptrace(struct task_struct *child, long request,
 	case PTRACE_SETREGS:	/* Set all gp regs in the child. */
 		return copy_regset_from_user(child, &user_ppc_native_view,
 					     REGSET_GPR,
-					     0, sizeof(struct pt_regs),
+					     0, sizeof(struct user_pt_regs),
 					     datavp);
 
 	case PTRACE_GETFPREGS: /* Get the child FPU state (FPR0...31 + FPSCR) */
-- 
2.17.1



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