signal: Introduce copy_siginfo_from_user and use it's return value
In preparation for using a smaller version of siginfo in the kernel
introduce copy_siginfo_from_user and use it when siginfo is copied from
userspace.
Make the pattern for using copy_siginfo_from_user and
copy_siginfo_from_user32 to capture the return value and return that
value on error.
This is a necessary prerequisite for using a smaller siginfo
in the kernel than the kernel exports to userspace.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
diff --git a/kernel/signal.c b/kernel/signal.c
index debb485..c0e289e6 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -2896,6 +2896,13 @@
return 0;
}
+int copy_siginfo_from_user(siginfo_t *to, const siginfo_t __user *from)
+{
+ if (copy_from_user(to, from, sizeof(struct siginfo)))
+ return -EFAULT;
+ return 0;
+}
+
#ifdef CONFIG_COMPAT
int copy_siginfo_to_user32(struct compat_siginfo __user *to,
const struct siginfo *from)
@@ -3323,8 +3330,9 @@
siginfo_t __user *, uinfo)
{
siginfo_t info;
- if (copy_from_user(&info, uinfo, sizeof(siginfo_t)))
- return -EFAULT;
+ int ret = copy_siginfo_from_user(&info, uinfo);
+ if (unlikely(ret))
+ return ret;
return do_rt_sigqueueinfo(pid, sig, &info);
}
@@ -3365,10 +3373,9 @@
siginfo_t __user *, uinfo)
{
siginfo_t info;
-
- if (copy_from_user(&info, uinfo, sizeof(siginfo_t)))
- return -EFAULT;
-
+ int ret = copy_siginfo_from_user(&info, uinfo);
+ if (unlikely(ret))
+ return ret;
return do_rt_tgsigqueueinfo(tgid, pid, sig, &info);
}
@@ -3380,9 +3387,9 @@
struct compat_siginfo __user *, uinfo)
{
siginfo_t info;
-
- if (copy_siginfo_from_user32(&info, uinfo))
- return -EFAULT;
+ int ret = copy_siginfo_from_user32(&info, uinfo);
+ if (unlikely(ret))
+ return ret;
return do_rt_tgsigqueueinfo(tgid, pid, sig, &info);
}
#endif