[PATCH] cleanup the usage of SEND_SIG_xxx constants

This patch simplifies some checks for magic siginfo values.  It should not
change the behaviour in any way.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/include/linux/sched.h b/include/linux/sched.h
index 41285a0e7258eb45e164a24bb1055050aa8e35d8..03b68a7b4b82ae7c775a375f1fe3aa0b6a9909ec 100644 (file)
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1084,6 +1084,11 @@ extern int do_sigaltstack(const stack_t __user *, stack_t __user *, unsigned lon
 #define SEND_SIG_PRIV  ((struct siginfo *) 1)
 #define SEND_SIG_FORCED        ((struct siginfo *) 2)
 
+static inline int is_si_special(const struct siginfo *info)
+{
+       return info <= SEND_SIG_FORCED;
+}
+
 /* True if we are on the alternate signal stack.  */
 
 static inline int on_sig_stack(unsigned long sp)

diff --git a/kernel/signal.c b/kernel/signal.c
index 1f7b2aaa4a39c7c128b18181b990d0b945a5dfff..27533b90c3476790460a72d6440f58d4271b8982 100644 (file)
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -651,9 +651,7 @@ static int check_kill_permission(int sig, struct siginfo *info,
        if (!valid_signal(sig))
                return error;
        error = -EPERM;
-       if ((info == SEND_SIG_NOINFO ||
-                       (info != SEND_SIG_PRIV && info != SEND_SIG_FORCED
-                               && SI_FROMUSER(info)))
+       if ((info == SEND_SIG_NOINFO || (!is_si_special(info) && SI_FROMUSER(info)))
            && ((sig != SIGCONT) ||
                (current->signal->session != t->signal->session))
            && (current->euid ^ t->suid) && (current->euid ^ t->uid)
@@ -802,7 +800,7 @@ static int send_signal(int sig, struct siginfo *info, struct task_struct *t,
           pass on the info struct.  */
 
        q = __sigqueue_alloc(t, GFP_ATOMIC, (sig < SIGRTMIN &&
-                                            (info < SEND_SIG_FORCED ||
+                                            (is_si_special(info) ||
                                              info->si_code >= 0)));
        if (q) {
                list_add_tail(&q->list, &signals->list);
@@ -825,16 +823,14 @@ static int send_signal(int sig, struct siginfo *info, struct task_struct *t,
                        copy_siginfo(&q->info, info);
                        break;
                }
-       } else {
-               if (sig >= SIGRTMIN
-                  && info != SEND_SIG_NOINFO && info != SEND_SIG_PRIV
-                  && info->si_code != SI_USER)
+       } else if (!is_si_special(info)) {
+               if (sig >= SIGRTMIN && info->si_code != SI_USER)
                /*
                 * Queue overflow, abort.  We may abort if the signal was rt
                 * and sent by user using something other than kill().
                 */
                        return -EAGAIN;
-               if ((info > SEND_SIG_PRIV) && (info->si_code == SI_TIMER))
+               if (info->si_code == SI_TIMER)
                        /*
                         * Set up a return to indicate that we dropped 
                         * the signal.
@@ -860,7 +856,7 @@ specific_send_sig_info(int sig, struct siginfo *info, struct task_struct *t)
                BUG();
        assert_spin_locked(&t->sighand->siglock);
 
-       if ((info > SEND_SIG_FORCED) && (info->si_code == SI_TIMER))
+       if (!is_si_special(info) && (info->si_code == SI_TIMER))
                /*
                 * Set up a return to indicate that we dropped the signal.
                 */
@@ -1052,7 +1048,7 @@ __group_send_sig_info(int sig, struct siginfo *info, struct task_struct *p)
        assert_spin_locked(&p->sighand->siglock);
        handle_stop_signal(sig, p);
 
-       if ((info > SEND_SIG_FORCED) && (info->si_code == SI_TIMER))
+       if (!is_si_special(info) && (info->si_code == SI_TIMER))
                /*
                 * Set up a return to indicate that we dropped the signal.
                 */

diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 295ac472faf199fdb2f99caa08d1235599646bb5..45c41490d521e22b07219345fe195f02e171ac27 100644 (file)
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -2713,8 +2713,7 @@ static int selinux_task_kill(struct task_struct *p, struct siginfo *info, int si
        if (rc)
                return rc;
 
-       if (info != SEND_SIG_NOINFO && (info == SEND_SIG_PRIV ||
-                                       info == SEND_SIG_FORCED || SI_FROMKERNEL(info)))
+       if (info != SEND_SIG_NOINFO && (is_si_special(info) || SI_FROMKERNEL(info)))
                return 0;
 
        if (!sig)