Merge tag 'lsk-v3.10-android-14.07' into develop-3.10

[firefly-linux-kernel-4.4.55.git] / fs / signalfd.c

diff --git a/fs/signalfd.c b/fs/signalfd.c
index 492465b451ddd34f6f60214fb48224687649faa9..424b7b65321fecbe2afff24cb3f3f69dfa81bc26 100644 (file)
--- a/fs/signalfd.c
+++ b/fs/signalfd.c
@@ -29,6 +29,23 @@
 #include <linux/anon_inodes.h>
 #include <linux/signalfd.h>
 #include <linux/syscalls.h>
+#include <linux/proc_fs.h>
+#include <linux/compat.h>
+
+void signalfd_cleanup(struct sighand_struct *sighand)
+{
+       wait_queue_head_t *wqh = &sighand->signalfd_wqh;
+       /*
+        * The lockless check can race with remove_wait_queue() in progress,
+        * but in this case its caller should run under rcu_read_lock() and
+        * sighand_cachep is SLAB_DESTROY_BY_RCU, we can safely return.
+        */
+       if (likely(!waitqueue_active(wqh)))
+               return;
+
+       /* wait_queue_t->func(POLLFREE) should do remove_wait_queue() */
+       wake_up_poll(wqh, POLLHUP | POLLFREE);
+}
 
 struct signalfd_ctx {
        sigset_t sigmask;
@@ -212,7 +229,24 @@ static ssize_t signalfd_read(struct file *file, char __user *buf, size_t count,
        return total ? total: ret;
 }
 
+#ifdef CONFIG_PROC_FS
+static int signalfd_show_fdinfo(struct seq_file *m, struct file *f)
+{
+       struct signalfd_ctx *ctx = f->private_data;
+       sigset_t sigmask;
+
+       sigmask = ctx->sigmask;
+       signotset(&sigmask);
+       render_sigset_t(m, "sigmask:\t", &sigmask);
+
+       return 0;
+}
+#endif
+
 static const struct file_operations signalfd_fops = {
+#ifdef CONFIG_PROC_FS
+       .show_fdinfo    = signalfd_show_fdinfo,
+#endif
        .release        = signalfd_release,
        .poll           = signalfd_poll,
        .read           = signalfd_read,
@@ -254,12 +288,12 @@ SYSCALL_DEFINE4(signalfd4, int, ufd, sigset_t __user *, user_mask,
                if (ufd < 0)
                        kfree(ctx);
        } else {
-               struct file *file = fget(ufd);
-               if (!file)
+               struct fd f = fdget(ufd);
+               if (!f.file)
                        return -EBADF;
-               ctx = file->private_data;
-               if (file->f_op != &signalfd_fops) {
-                       fput(file);
+               ctx = f.file->private_data;
+               if (f.file->f_op != &signalfd_fops) {
+                       fdput(f);
                        return -EINVAL;
                }
                spin_lock_irq(&current->sighand->siglock);
@@ -267,7 +301,7 @@ SYSCALL_DEFINE4(signalfd4, int, ufd, sigset_t __user *, user_mask,
                spin_unlock_irq(&current->sighand->siglock);
 
                wake_up(&current->sighand->signalfd_wqh);
-               fput(file);
+               fdput(f);
        }
 
        return ufd;
@@ -278,3 +312,33 @@ SYSCALL_DEFINE3(signalfd, int, ufd, sigset_t __user *, user_mask,
 {
        return sys_signalfd4(ufd, user_mask, sizemask, 0);
 }
+
+#ifdef CONFIG_COMPAT
+COMPAT_SYSCALL_DEFINE4(signalfd4, int, ufd,
+                    const compat_sigset_t __user *,sigmask,
+                    compat_size_t, sigsetsize,
+                    int, flags)
+{
+       compat_sigset_t ss32;
+       sigset_t tmp;
+       sigset_t __user *ksigmask;
+
+       if (sigsetsize != sizeof(compat_sigset_t))
+               return -EINVAL;
+       if (copy_from_user(&ss32, sigmask, sizeof(ss32)))
+               return -EFAULT;
+       sigset_from_compat(&tmp, &ss32);
+       ksigmask = compat_alloc_user_space(sizeof(sigset_t));
+       if (copy_to_user(ksigmask, &tmp, sizeof(sigset_t)))
+               return -EFAULT;
+
+       return sys_signalfd4(ufd, ksigmask, sizeof(sigset_t), flags);
+}
+
+COMPAT_SYSCALL_DEFINE3(signalfd, int, ufd,
+                    const compat_sigset_t __user *,sigmask,
+                    compat_size_t, sigsetsize)
+{
+       return compat_sys_signalfd4(ufd, sigmask, sigsetsize, 0);
+}
+#endif