netns xfrm: fix "ip xfrm state|policy count" misreport
[safe/jmp/linux-2.6] / fs / fcntl.c
index ae41308..97e01dc 100644 (file)
@@ -263,6 +263,79 @@ pid_t f_getown(struct file *filp)
        return pid;
 }
 
+static int f_setown_ex(struct file *filp, unsigned long arg)
+{
+       struct f_owner_ex * __user owner_p = (void * __user)arg;
+       struct f_owner_ex owner;
+       struct pid *pid;
+       int type;
+       int ret;
+
+       ret = copy_from_user(&owner, owner_p, sizeof(owner));
+       if (ret)
+               return ret;
+
+       switch (owner.type) {
+       case F_OWNER_TID:
+               type = PIDTYPE_MAX;
+               break;
+
+       case F_OWNER_PID:
+               type = PIDTYPE_PID;
+               break;
+
+       case F_OWNER_PGRP:
+               type = PIDTYPE_PGID;
+               break;
+
+       default:
+               return -EINVAL;
+       }
+
+       rcu_read_lock();
+       pid = find_vpid(owner.pid);
+       if (owner.pid && !pid)
+               ret = -ESRCH;
+       else
+               ret = __f_setown(filp, pid, type, 1);
+       rcu_read_unlock();
+
+       return ret;
+}
+
+static int f_getown_ex(struct file *filp, unsigned long arg)
+{
+       struct f_owner_ex * __user owner_p = (void * __user)arg;
+       struct f_owner_ex owner;
+       int ret = 0;
+
+       read_lock(&filp->f_owner.lock);
+       owner.pid = pid_vnr(filp->f_owner.pid);
+       switch (filp->f_owner.pid_type) {
+       case PIDTYPE_MAX:
+               owner.type = F_OWNER_TID;
+               break;
+
+       case PIDTYPE_PID:
+               owner.type = F_OWNER_PID;
+               break;
+
+       case PIDTYPE_PGID:
+               owner.type = F_OWNER_PGRP;
+               break;
+
+       default:
+               WARN_ON(1);
+               ret = -EINVAL;
+               break;
+       }
+       read_unlock(&filp->f_owner.lock);
+
+       if (!ret)
+               ret = copy_to_user(owner_p, &owner, sizeof(owner));
+       return ret;
+}
+
 static long do_fcntl(int fd, unsigned int cmd, unsigned long arg,
                struct file *filp)
 {
@@ -313,6 +386,12 @@ static long do_fcntl(int fd, unsigned int cmd, unsigned long arg,
        case F_SETOWN:
                err = f_setown(filp, arg, 1);
                break;
+       case F_GETOWN_EX:
+               err = f_getown_ex(filp, arg);
+               break;
+       case F_SETOWN_EX:
+               err = f_setown_ex(filp, arg);
+               break;
        case F_GETSIG:
                err = filp->f_owner.signum;
                break;
@@ -428,8 +507,7 @@ static inline int sigio_perm(struct task_struct *p,
 
 static void send_sigio_to_task(struct task_struct *p,
                               struct fown_struct *fown,
-                              int fd,
-                              int reason)
+                              int fd, int reason, int group)
 {
        /*
         * F_SETSIG can change ->signum lockless in parallel, make
@@ -461,11 +539,11 @@ static void send_sigio_to_task(struct task_struct *p,
                        else
                                si.si_band = band_table[reason - POLL_IN];
                        si.si_fd    = fd;
-                       if (!group_send_sig_info(signum, &si, p))
+                       if (!do_send_sig_info(signum, &si, p, group))
                                break;
                /* fall-through: fall back on the old plain SIGIO signal */
                case 0:
-                       group_send_sig_info(SIGIO, SEND_SIG_PRIV, p);
+                       do_send_sig_info(SIGIO, SEND_SIG_PRIV, p, group);
        }
 }
 
@@ -474,16 +552,23 @@ void send_sigio(struct fown_struct *fown, int fd, int band)
        struct task_struct *p;
        enum pid_type type;
        struct pid *pid;
+       int group = 1;
        
        read_lock(&fown->lock);
+
        type = fown->pid_type;
+       if (type == PIDTYPE_MAX) {
+               group = 0;
+               type = PIDTYPE_PID;
+       }
+
        pid = fown->pid;
        if (!pid)
                goto out_unlock_fown;
        
        read_lock(&tasklist_lock);
        do_each_pid_task(pid, type, p) {
-               send_sigio_to_task(p, fown, fd, band);
+               send_sigio_to_task(p, fown, fd, band, group);
        } while_each_pid_task(pid, type, p);
        read_unlock(&tasklist_lock);
  out_unlock_fown:
@@ -491,10 +576,10 @@ void send_sigio(struct fown_struct *fown, int fd, int band)
 }
 
 static void send_sigurg_to_task(struct task_struct *p,
-                                struct fown_struct *fown)
+                               struct fown_struct *fown, int group)
 {
        if (sigio_perm(p, fown, SIGURG))
-               group_send_sig_info(SIGURG, SEND_SIG_PRIV, p);
+               do_send_sig_info(SIGURG, SEND_SIG_PRIV, p, group);
 }
 
 int send_sigurg(struct fown_struct *fown)
@@ -502,10 +587,17 @@ int send_sigurg(struct fown_struct *fown)
        struct task_struct *p;
        enum pid_type type;
        struct pid *pid;
+       int group = 1;
        int ret = 0;
        
        read_lock(&fown->lock);
+
        type = fown->pid_type;
+       if (type == PIDTYPE_MAX) {
+               group = 0;
+               type = PIDTYPE_PID;
+       }
+
        pid = fown->pid;
        if (!pid)
                goto out_unlock_fown;
@@ -514,7 +606,7 @@ int send_sigurg(struct fown_struct *fown)
        
        read_lock(&tasklist_lock);
        do_each_pid_task(pid, type, p) {
-               send_sigurg_to_task(p, fown);
+               send_sigurg_to_task(p, fown, group);
        } while_each_pid_task(pid, type, p);
        read_unlock(&tasklist_lock);
  out_unlock_fown:
@@ -526,60 +618,90 @@ static DEFINE_RWLOCK(fasync_lock);
 static struct kmem_cache *fasync_cache __read_mostly;
 
 /*
- * fasync_helper() is used by almost all character device drivers
- * to set up the fasync queue. It returns negative on error, 0 if it did
- * no changes and positive if it added/deleted the entry.
+ * Remove a fasync entry. If successfully removed, return
+ * positive and clear the FASYNC flag. If no entry exists,
+ * do nothing and return 0.
+ *
+ * NOTE! It is very important that the FASYNC flag always
+ * match the state "is the filp on a fasync list".
+ *
+ * We always take the 'filp->f_lock', in since fasync_lock
+ * needs to be irq-safe.
  */
-int fasync_helper(int fd, struct file * filp, int on, struct fasync_struct **fapp)
+static int fasync_remove_entry(struct file *filp, struct fasync_struct **fapp)
 {
        struct fasync_struct *fa, **fp;
-       struct fasync_struct *new = NULL;
        int result = 0;
 
-       if (on) {
-               new = kmem_cache_alloc(fasync_cache, GFP_KERNEL);
-               if (!new)
-                       return -ENOMEM;
+       spin_lock(&filp->f_lock);
+       write_lock_irq(&fasync_lock);
+       for (fp = fapp; (fa = *fp) != NULL; fp = &fa->fa_next) {
+               if (fa->fa_file != filp)
+                       continue;
+               *fp = fa->fa_next;
+               kmem_cache_free(fasync_cache, fa);
+               filp->f_flags &= ~FASYNC;
+               result = 1;
+               break;
        }
+       write_unlock_irq(&fasync_lock);
+       spin_unlock(&filp->f_lock);
+       return result;
+}
+
+/*
+ * Add a fasync entry. Return negative on error, positive if
+ * added, and zero if did nothing but change an existing one.
+ *
+ * NOTE! It is very important that the FASYNC flag always
+ * match the state "is the filp on a fasync list".
+ */
+static int fasync_add_entry(int fd, struct file *filp, struct fasync_struct **fapp)
+{
+       struct fasync_struct *new, *fa, **fp;
+       int result = 0;
+
+       new = kmem_cache_alloc(fasync_cache, GFP_KERNEL);
+       if (!new)
+               return -ENOMEM;
 
-       /*
-        * We need to take f_lock first since it's not an IRQ-safe
-        * lock.
-        */
        spin_lock(&filp->f_lock);
        write_lock_irq(&fasync_lock);
        for (fp = fapp; (fa = *fp) != NULL; fp = &fa->fa_next) {
-               if (fa->fa_file == filp) {
-                       if(on) {
-                               fa->fa_fd = fd;
-                               kmem_cache_free(fasync_cache, new);
-                       } else {
-                               *fp = fa->fa_next;
-                               kmem_cache_free(fasync_cache, fa);
-                               result = 1;
-                       }
-                       goto out;
-               }
+               if (fa->fa_file != filp)
+                       continue;
+               fa->fa_fd = fd;
+               kmem_cache_free(fasync_cache, new);
+               goto out;
        }
 
-       if (on) {
-               new->magic = FASYNC_MAGIC;
-               new->fa_file = filp;
-               new->fa_fd = fd;
-               new->fa_next = *fapp;
-               *fapp = new;
-               result = 1;
-       }
+       new->magic = FASYNC_MAGIC;
+       new->fa_file = filp;
+       new->fa_fd = fd;
+       new->fa_next = *fapp;
+       *fapp = new;
+       result = 1;
+       filp->f_flags |= FASYNC;
+
 out:
-       if (on)
-               filp->f_flags |= FASYNC;
-       else
-               filp->f_flags &= ~FASYNC;
        write_unlock_irq(&fasync_lock);
        spin_unlock(&filp->f_lock);
        return result;
 }
 
+/*
+ * fasync_helper() is used by almost all character device drivers
+ * to set up the fasync queue, and for regular files by the file
+ * lease code. It returns negative on error, 0 if it did no changes
+ * and positive if it added/deleted the entry.
+ */
+int fasync_helper(int fd, struct file * filp, int on, struct fasync_struct **fapp)
+{
+       if (!on)
+               return fasync_remove_entry(filp, fapp);
+       return fasync_add_entry(fd, filp, fapp);
+}
+
 EXPORT_SYMBOL(fasync_helper);
 
 void __kill_fasync(struct fasync_struct *fa, int sig, int band)