From 85487edd252fa04718dcd735bc0f41213bbb9546 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Fri, 22 Aug 2014 14:20:24 +0100 Subject: [PATCH] arm64: ptrace: fix compat reg getter/setter return values copy_{to,from}_user return the number of bytes remaining on failure, not an error code. This patch returns -EFAULT when the copy operation didn't complete, rather than expose the number of bytes not copied directly to userspace. Signed-off-by: Will Deacon --- arch/arm64/kernel/ptrace.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c index 2ac998878001..fe63ac5e9bf5 100644 --- a/arch/arm64/kernel/ptrace.c +++ b/arch/arm64/kernel/ptrace.c @@ -663,8 +663,10 @@ static int compat_gpr_get(struct task_struct *target, kbuf += sizeof(reg); } else { ret = copy_to_user(ubuf, ®, sizeof(reg)); - if (ret) + if (ret) { + ret = -EFAULT; break; + } ubuf += sizeof(reg); } @@ -702,8 +704,10 @@ static int compat_gpr_set(struct task_struct *target, kbuf += sizeof(reg); } else { ret = copy_from_user(®, ubuf, sizeof(reg)); - if (ret) - return ret; + if (ret) { + ret = -EFAULT; + break; + } ubuf += sizeof(reg); } -- 2.20.1