generic compat_sys_rt_sigqueueinfo()

conditional on GENERIC_COMPAT_RT_SIGQUEUEINFO; by the end of that series
it will become the same thing as COMPAT and conditional will die out.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 32 insertions, 13 deletions

diff --git a/kernel/signal.c b/kernel/signal.c
index 3040c34..6cd3023 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -2983,6 +2983,22 @@ SYSCALL_DEFINE2(tkill, pid_t, pid, int, sig)
 	return do_tkill(0, pid, sig);
 }
 
+static int do_rt_sigqueueinfo(pid_t pid, int sig, siginfo_t *info)
+{
+	/* Not even root can pretend to send signals from the kernel.
+	 * Nor can they impersonate a kill()/tgkill(), which adds source info.
+	 */
+	if (info->si_code >= 0 || info->si_code == SI_TKILL) {
+		/* We used to allow any < 0 si_code */
+		WARN_ON_ONCE(info->si_code < 0);
+		return -EPERM;
+	}
+	info->si_signo = sig;
+
+	/* POSIX.1b doesn't mention process groups.  */
+	return kill_proc_info(sig, info, pid);
+}
+
 /**
  *  sys_rt_sigqueueinfo - send signal information to a signal
  *  @pid: the PID of the thread
@@ -2993,23 +3009,26 @@ SYSCALL_DEFINE3(rt_sigqueueinfo, pid_t, pid, int, sig,
 		siginfo_t __user *, uinfo)
 {
 	siginfo_t info;
-
 	if (copy_from_user(&info, uinfo, sizeof(siginfo_t)))
 		return -EFAULT;
+	return do_rt_sigqueueinfo(pid, sig, &info);
+}
 
-	/* Not even root can pretend to send signals from the kernel.
-	 * Nor can they impersonate a kill()/tgkill(), which adds source info.
-	 */
-	if (info.si_code >= 0 || info.si_code == SI_TKILL) {
-		/* We used to allow any < 0 si_code */
-		WARN_ON_ONCE(info.si_code < 0);
-		return -EPERM;
-	}
-	info.si_signo = sig;
-
-	/* POSIX.1b doesn't mention process groups.  */
-	return kill_proc_info(sig, &info, pid);
+#ifdef CONFIG_COMPAT
+#ifdef CONFIG_GENERIC_COMPAT_RT_SIGQUEUEINFO
+COMPAT_SYSCALL_DEFINE3(rt_sigqueueinfo,
+			compat_pid_t, pid,
+			int, sig,
+			struct compat_siginfo __user *, uinfo)
+{
+	siginfo_t info;
+	int ret = copy_siginfo_from_user32(&info, uinfo);
+	if (unlikely(ret))
+		return ret;
+	return do_rt_sigqueueinfo(pid, sig, &info);
 }
+#endif
+#endif
 
 long do_rt_tgsigqueueinfo(pid_t tgid, pid_t pid, int sig, siginfo_t *info)
 {