s390/ptrace: fix PTRACE_GET_LAST_BREAK error handling

BugLink: https://bugs.launchpad.net/bugs/2023929
[ Upstream commit f9bbf25e7b2b74b52b2f269216a92657774f239c ]

Return -EFAULT if put_user() for the PTRACE_GET_LAST_BREAK
request fails, instead of silently ignoring it.

Reviewed-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>

diff --git a/arch/s390/kernel/ptrace.c b/arch/s390/kernel/ptrace.c
index 53e0209229f87a697d9cb63c0de30ce07cdf027a..092b16b4dd4f6b05fa6aa22596a384b909dd5efa 100644 (file)
--- a/arch/s390/kernel/ptrace.c
+++ b/arch/s390/kernel/ptrace.c
@@ -474,9 +474,7 @@ long arch_ptrace(struct task_struct *child, long request,
                }
                return 0;
        case PTRACE_GET_LAST_BREAK:
-               put_user(child->thread.last_break,
-                        (unsigned long __user *) data);
-               return 0;
+               return put_user(child->thread.last_break, (unsigned long __user *)data);
        case PTRACE_ENABLE_TE:
                if (!MACHINE_HAS_TE)
                        return -EIO;
@@ -824,9 +822,7 @@ long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
                }
                return 0;
        case PTRACE_GET_LAST_BREAK:
-               put_user(child->thread.last_break,
-                        (unsigned int __user *) data);
-               return 0;
+               return put_user(child->thread.last_break, (unsigned int __user *)data);
        }
        return compat_ptrace_request(child, request, addr, data);
 }