* Copyright (C) 1991, 1992 Linus Torvalds
*/
+#include <linux/syscalls.h>
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/fs.h>
#include <linux/file.h>
+#include <linux/capability.h>
#include <linux/dnotify.h>
#include <linux/smp_lock.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/security.h>
#include <linux/ptrace.h>
+#include <linux/signal.h>
+#include <linux/rcupdate.h>
#include <linux/vs_limit.h>
#include <asm/poll.h>
void fastcall set_close_on_exec(unsigned int fd, int flag)
{
struct files_struct *files = current->files;
+ struct fdtable *fdt;
spin_lock(&files->file_lock);
+ fdt = files_fdtable(files);
if (flag)
- FD_SET(fd, files->close_on_exec);
+ FD_SET(fd, fdt->close_on_exec);
else
- FD_CLR(fd, files->close_on_exec);
+ FD_CLR(fd, fdt->close_on_exec);
spin_unlock(&files->file_lock);
}
-static inline int get_close_on_exec(unsigned int fd)
+static int get_close_on_exec(unsigned int fd)
{
struct files_struct *files = current->files;
+ struct fdtable *fdt;
int res;
- spin_lock(&files->file_lock);
- res = FD_ISSET(fd, files->close_on_exec);
- spin_unlock(&files->file_lock);
+ rcu_read_lock();
+ fdt = files_fdtable(files);
+ res = FD_ISSET(fd, fdt->close_on_exec);
+ rcu_read_unlock();
return res;
}
-
-/* Expand files. Return <0 on error; 0 nothing done; 1 files expanded,
- * we may have blocked.
- *
- * Should be called with the files->file_lock spinlock held for write.
- */
-static int expand_files(struct files_struct *files, int nr)
-{
- int err, expand = 0;
-#ifdef FDSET_DEBUG
- printk (KERN_ERR "%s %d: nr = %d\n", __FUNCTION__, current->pid, nr);
-#endif
-
- if (nr >= files->max_fdset) {
- expand = 1;
- if ((err = expand_fdset(files, nr)))
- goto out;
- }
- if (nr >= files->max_fds) {
- expand = 1;
- if ((err = expand_fd_array(files, nr)))
- goto out;
- }
- err = expand;
- out:
-#ifdef FDSET_DEBUG
- if (err)
- printk (KERN_ERR "%s %d: return %d\n", __FUNCTION__, current->pid, err);
-#endif
- return err;
-}
-
/*
* locate_fd finds a free file descriptor in the open_fds fdset,
* expanding the fd arrays if necessary. Must be called with the
unsigned int newfd;
unsigned int start;
int error;
+ struct fdtable *fdt;
error = -EINVAL;
- if (orig_start >= current->rlim[RLIMIT_NOFILE].rlim_cur)
+ if (orig_start >= current->signal->rlim[RLIMIT_NOFILE].rlim_cur)
goto out;
repeat:
+ fdt = files_fdtable(files);
/*
* Someone might have closed fd's in the range
- * orig_start..files->next_fd
+ * orig_start..fdt->next_fd
*/
start = orig_start;
if (start < files->next_fd)
start = files->next_fd;
newfd = start;
- if (start < files->max_fdset) {
- newfd = find_next_zero_bit(files->open_fds->fds_bits,
- files->max_fdset, start);
- }
+ if (start < fdt->max_fds)
+ newfd = find_next_zero_bit(fdt->open_fds->fds_bits,
+ fdt->max_fds, start);
error = -EMFILE;
- if (newfd >= current->rlim[RLIMIT_NOFILE].rlim_cur)
+ if (newfd >= current->signal->rlim[RLIMIT_NOFILE].rlim_cur)
goto out;
if (!vx_files_avail(1))
goto out;
if (error)
goto repeat;
+ /*
+ * We reacquired files_lock, so we are safe as long as
+ * we reacquire the fdtable pointer and use it while holding
+ * the lock, no one can free it during that time.
+ */
if (start <= files->next_fd)
files->next_fd = newfd + 1;
-
+
error = newfd;
out:
static int dupfd(struct file *file, unsigned int start)
{
struct files_struct * files = current->files;
+ struct fdtable *fdt;
int fd;
spin_lock(&files->file_lock);
fd = locate_fd(files, file, start);
if (fd >= 0) {
- FD_SET(fd, files->open_fds);
- FD_CLR(fd, files->close_on_exec);
+ /* locate_fd() may have expanded fdtable, load the ptr */
+ fdt = files_fdtable(files);
+ FD_SET(fd, fdt->open_fds);
+ FD_CLR(fd, fdt->close_on_exec);
spin_unlock(&files->file_lock);
vx_openfd_inc(fd);
fd_install(fd, file);
int err = -EBADF;
struct file * file, *tofree;
struct files_struct * files = current->files;
+ struct fdtable *fdt;
spin_lock(&files->file_lock);
if (!(file = fcheck(oldfd)))
if (newfd == oldfd)
goto out_unlock;
err = -EBADF;
- if (newfd >= current->rlim[RLIMIT_NOFILE].rlim_cur)
+ if (newfd >= current->signal->rlim[RLIMIT_NOFILE].rlim_cur)
goto out_unlock;
get_file(file); /* We are now finished with oldfd */
/* Yes. It's a race. In user space. Nothing sane to do */
err = -EBUSY;
- tofree = files->fd[newfd];
- if (!tofree && FD_ISSET(newfd, files->open_fds))
+ fdt = files_fdtable(files);
+ tofree = fdt->fd[newfd];
+ if (!tofree && FD_ISSET(newfd, fdt->open_fds))
goto out_fput;
- files->fd[newfd] = file;
- FD_SET(newfd, files->open_fds);
- FD_CLR(newfd, files->close_on_exec);
+ rcu_assign_pointer(fdt->fd[newfd], file);
+ FD_SET(newfd, fdt->open_fds);
+ FD_CLR(newfd, fdt->close_on_exec);
spin_unlock(&files->file_lock);
- vx_openfd_inc(newfd);
if (tofree)
filp_close(tofree, files);
+ else
+ vx_openfd_inc(newfd); /* fd was unused */
+
err = newfd;
out:
return err;
return ret;
}
-#define SETFL_MASK (O_APPEND | O_NONBLOCK | O_NDELAY | FASYNC | O_DIRECT)
+#define SETFL_MASK (O_APPEND | O_NONBLOCK | O_NDELAY | FASYNC | O_DIRECT | O_NOATIME)
static int setfl(int fd, struct file * filp, unsigned long arg)
{
- struct inode * inode = filp->f_dentry->d_inode;
+ struct inode * inode = filp->f_path.dentry->d_inode;
int error = 0;
- /* O_APPEND cannot be cleared if the file is marked as append-only */
- if (!(arg & O_APPEND) && IS_APPEND(inode))
+ /*
+ * O_APPEND cannot be cleared if the file is marked as append-only
+ * and the file is open for write.
+ */
+ if (((arg ^ filp->f_flags) & O_APPEND) && IS_APPEND(inode))
return -EPERM;
+ /* O_NOATIME can only be set by the owner or superuser */
+ if ((arg & O_NOATIME) && !(filp->f_flags & O_NOATIME))
+ if (current->fsuid != inode->i_uid && !capable(CAP_FOWNER))
+ return -EPERM;
+
/* required for strict SunOS emulation */
if (O_NONBLOCK != O_NDELAY)
if (arg & O_NDELAY)
return -EINVAL;
}
+ if (filp->f_op && filp->f_op->check_flags)
+ error = filp->f_op->check_flags(arg);
+ if (error)
+ return error;
+
lock_kernel();
if ((arg ^ filp->f_flags) & FASYNC) {
if (filp->f_op && filp->f_op->fasync) {
return error;
}
-static void f_modown(struct file *filp, unsigned long pid,
+static void f_modown(struct file *filp, struct pid *pid, enum pid_type type,
uid_t uid, uid_t euid, int force)
{
write_lock_irq(&filp->f_owner.lock);
if (force || !filp->f_owner.pid) {
- filp->f_owner.pid = pid;
+ put_pid(filp->f_owner.pid);
+ filp->f_owner.pid = get_pid(pid);
+ filp->f_owner.pid_type = type;
filp->f_owner.uid = uid;
filp->f_owner.euid = euid;
}
write_unlock_irq(&filp->f_owner.lock);
}
-int f_setown(struct file *filp, unsigned long arg, int force)
+int __f_setown(struct file *filp, struct pid *pid, enum pid_type type,
+ int force)
{
int err;
if (err)
return err;
- f_modown(filp, arg, current->uid, current->euid, force);
+ f_modown(filp, pid, type, current->uid, current->euid, force);
return 0;
}
+EXPORT_SYMBOL(__f_setown);
+int f_setown(struct file *filp, unsigned long arg, int force)
+{
+ enum pid_type type;
+ struct pid *pid;
+ int who = arg;
+ int result;
+ type = PIDTYPE_PID;
+ if (who < 0) {
+ type = PIDTYPE_PGID;
+ who = -who;
+ }
+ rcu_read_lock();
+ pid = find_pid(who);
+ result = __f_setown(filp, pid, type, force);
+ rcu_read_unlock();
+ return result;
+}
EXPORT_SYMBOL(f_setown);
void f_delown(struct file *filp)
{
- f_modown(filp, 0, 0, 0, 1);
+ f_modown(filp, NULL, PIDTYPE_PID, 0, 0, 1);
}
-EXPORT_SYMBOL(f_delown);
+pid_t f_getown(struct file *filp)
+{
+ pid_t pid;
+ read_lock(&filp->f_owner.lock);
+ pid = pid_nr(filp->f_owner.pid);
+ if (filp->f_owner.pid_type == PIDTYPE_PGID)
+ pid = -pid;
+ read_unlock(&filp->f_owner.lock);
+ return pid;
+}
-long generic_file_fcntl(int fd, unsigned int cmd,
- unsigned long arg, struct file *filp)
+static long do_fcntl(int fd, unsigned int cmd, unsigned long arg,
+ struct file *filp)
{
long err = -EINVAL;
break;
case F_SETLK:
case F_SETLKW:
- err = fcntl_setlk(filp, cmd, (struct flock __user *) arg);
+ err = fcntl_setlk(fd, filp, cmd, (struct flock __user *) arg);
break;
case F_GETOWN:
/*
* current syscall conventions, the only way
* to fix this will be in libc.
*/
- err = filp->f_owner.pid;
+ err = f_getown(filp);
force_successful_syscall_return();
break;
case F_SETOWN:
break;
case F_SETSIG:
/* arg == 0 restores default behaviour. */
- if (arg < 0 || arg > _NSIG) {
+ if (!valid_signal(arg)) {
break;
}
err = 0;
}
return err;
}
-EXPORT_SYMBOL(generic_file_fcntl);
-
-static long do_fcntl(int fd, unsigned int cmd,
- unsigned long arg, struct file *filp)
-{
- if (filp->f_op && filp->f_op->fcntl)
- return filp->f_op->fcntl(fd, cmd, arg, filp);
- return generic_file_fcntl(fd, cmd, arg, filp);
-}
-asmlinkage long sys_fcntl(int fd, unsigned int cmd, unsigned long arg)
+asmlinkage long sys_fcntl(unsigned int fd, unsigned int cmd, unsigned long arg)
{
struct file *filp;
long err = -EBADF;
break;
case F_SETLK64:
case F_SETLKW64:
- err = fcntl_setlk64(filp, cmd, (struct flock64 __user *) arg);
+ err = fcntl_setlk64(fd, filp, cmd,
+ (struct flock64 __user *) arg);
break;
default:
err = do_fcntl(fd, cmd, arg, filp);
/* Table to convert sigio signal codes into poll band bitmaps */
-static long band_table[NSIGPOLL] = {
+static const long band_table[NSIGPOLL] = {
POLLIN | POLLRDNORM, /* POLL_IN */
POLLOUT | POLLWRNORM | POLLWRBAND, /* POLL_OUT */
POLLIN | POLLRDNORM | POLLMSG, /* POLL_MSG */
};
static inline int sigio_perm(struct task_struct *p,
- struct fown_struct *fown)
+ struct fown_struct *fown, int sig)
{
- return ((fown->euid == 0) ||
- (fown->euid == p->suid) || (fown->euid == p->uid) ||
- (fown->uid == p->suid) || (fown->uid == p->uid));
+ return (((fown->euid == 0) ||
+ (fown->euid == p->suid) || (fown->euid == p->uid) ||
+ (fown->uid == p->suid) || (fown->uid == p->uid)) &&
+ !security_file_send_sigiotask(p, fown, sig));
}
static void send_sigio_to_task(struct task_struct *p,
int fd,
int reason)
{
- if (!sigio_perm(p, fown))
- return;
-
- if (security_file_send_sigiotask(p, fown, fd, reason))
+ if (!sigio_perm(p, fown, fown->signum))
return;
switch (fown->signum) {
/* Make sure we are called with one of the POLL_*
reasons, otherwise we could leak kernel stack into
userspace. */
- if ((reason & __SI_MASK) != __SI_POLL)
- BUG();
+ BUG_ON((reason & __SI_MASK) != __SI_POLL);
if (reason - POLL_IN >= NSIGPOLL)
si.si_band = ~0L;
else
si.si_band = band_table[reason - POLL_IN];
si.si_fd = fd;
- if (!send_sig_info(fown->signum, &si, p))
+ if (!group_send_sig_info(fown->signum, &si, p))
break;
/* fall-through: fall back on the old plain SIGIO signal */
case 0:
- send_group_sig_info(SIGIO, SEND_SIG_PRIV, p);
+ group_send_sig_info(SIGIO, SEND_SIG_PRIV, p);
}
}
void send_sigio(struct fown_struct *fown, int fd, int band)
{
struct task_struct *p;
- int pid;
+ enum pid_type type;
+ struct pid *pid;
read_lock(&fown->lock);
+ type = fown->pid_type;
pid = fown->pid;
if (!pid)
goto out_unlock_fown;
read_lock(&tasklist_lock);
- if (pid > 0) {
- p = find_task_by_pid(pid);
- if (p) {
- send_sigio_to_task(p, fown, fd, band);
- }
- } else {
- struct list_head *l;
- struct pid *pidptr;
- for_each_task_pid(-pid, PIDTYPE_PGID, p, l, pidptr) {
- send_sigio_to_task(p, fown, fd, band);
- }
- }
+ do_each_pid_task(pid, type, p) {
+ send_sigio_to_task(p, fown, fd, band);
+ } while_each_pid_task(pid, type, p);
read_unlock(&tasklist_lock);
out_unlock_fown:
read_unlock(&fown->lock);
static void send_sigurg_to_task(struct task_struct *p,
struct fown_struct *fown)
{
- if (sigio_perm(p, fown))
- send_group_sig_info(SIGURG, SEND_SIG_PRIV, p);
+ if (sigio_perm(p, fown, SIGURG))
+ group_send_sig_info(SIGURG, SEND_SIG_PRIV, p);
}
int send_sigurg(struct fown_struct *fown)
{
struct task_struct *p;
- int pid, ret = 0;
+ enum pid_type type;
+ struct pid *pid;
+ int ret = 0;
read_lock(&fown->lock);
+ type = fown->pid_type;
pid = fown->pid;
if (!pid)
goto out_unlock_fown;
ret = 1;
read_lock(&tasklist_lock);
- if (pid > 0) {
- p = find_task_by_pid(pid);
- if (p) {
- send_sigurg_to_task(p, fown);
- }
- } else {
- struct list_head *l;
- struct pid *pidptr;
- for_each_task_pid(-pid, PIDTYPE_PGID, p, l, pidptr) {
- send_sigurg_to_task(p, fown);
- }
- }
+ do_each_pid_task(pid, type, p) {
+ send_sigurg_to_task(p, fown);
+ } while_each_pid_task(pid, type, p);
read_unlock(&tasklist_lock);
out_unlock_fown:
read_unlock(&fown->lock);
return ret;
}
-static rwlock_t fasync_lock = RW_LOCK_UNLOCKED;
-static kmem_cache_t *fasync_cache;
+EXPORT_SYMBOL(send_sigurg);
+
+static DEFINE_RWLOCK(fasync_lock);
+static struct kmem_cache *fasync_cache __read_mostly;
/*
* fasync_helper() is used by some character device drivers (mainly mice)
int result = 0;
if (on) {
- new = kmem_cache_alloc(fasync_cache, SLAB_KERNEL);
+ new = kmem_cache_alloc(fasync_cache, GFP_KERNEL);
if (!new)
return -ENOMEM;
}