#include <linux/signal.h>
#include <linux/rcupdate.h>
#include <linux/pid_namespace.h>
-#include <linux/smp_lock.h>
#include <asm/poll.h>
#include <asm/siginfo.h>
{
if (unlikely(newfd == oldfd)) { /* corner case */
struct files_struct *files = current->files;
+ int retval = oldfd;
+
rcu_read_lock();
if (!fcheck_files(files, oldfd))
- oldfd = -EBADF;
+ retval = -EBADF;
rcu_read_unlock();
- return oldfd;
+ return retval;
}
return sys_dup3(oldfd, newfd, 0);
}
error = filp->f_op->fasync(fd, filp, (arg & FASYNC) != 0);
if (error < 0)
goto out;
+ if (error > 0)
+ error = 0;
}
spin_lock(&filp->f_lock);
filp->f_flags = (arg & SETFL_MASK) | (filp->f_flags & ~SETFL_MASK);
}
static void f_modown(struct file *filp, struct pid *pid, enum pid_type type,
- uid_t uid, uid_t euid, int force)
+ int force)
{
write_lock_irq(&filp->f_owner.lock);
if (force || !filp->f_owner.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;
+
+ if (pid) {
+ const struct cred *cred = current_cred();
+ filp->f_owner.uid = cred->uid;
+ filp->f_owner.euid = cred->euid;
+ }
}
write_unlock_irq(&filp->f_owner.lock);
}
int __f_setown(struct file *filp, struct pid *pid, enum pid_type type,
int force)
{
- const struct cred *cred = current_cred();
int err;
-
+
err = security_file_set_fowner(filp);
if (err)
return err;
- f_modown(filp, pid, type, cred->uid, cred->euid, force);
+ f_modown(filp, pid, type, force);
return 0;
}
EXPORT_SYMBOL(__f_setown);
void f_delown(struct file *filp)
{
- f_modown(filp, NULL, PIDTYPE_PID, 0, 0, 1);
+ f_modown(filp, NULL, PIDTYPE_PID, 1);
}
pid_t f_getown(struct file *filp)
}
static void send_sigio_to_task(struct task_struct *p,
- struct fown_struct *fown,
+ struct fown_struct *fown,
int fd,
int reason)
{
- if (!sigio_perm(p, fown, fown->signum))
+ /*
+ * F_SETSIG can change ->signum lockless in parallel, make
+ * sure we read it once and use the same value throughout.
+ */
+ int signum = ACCESS_ONCE(fown->signum);
+
+ if (!sigio_perm(p, fown, signum))
return;
- switch (fown->signum) {
+ switch (signum) {
siginfo_t si;
default:
/* Queue a rt signal with the appropriate fd as its
delivered even if we can't queue. Failure to
queue in this case _should_ be reported; we fall
back to SIGIO in that case. --sct */
- si.si_signo = fown->signum;
+ si.si_signo = signum;
si.si_errno = 0;
si.si_code = reason;
/* Make sure we are called with one of the POLL_*
else
si.si_band = band_table[reason - POLL_IN];
si.si_fd = fd;
- if (!group_send_sig_info(fown->signum, &si, p))
+ if (!group_send_sig_info(signum, &si, p))
break;
/* fall-through: fall back on the old plain SIGIO signal */
case 0:
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) {
result = 1;
}
out:
- /* Fix up FASYNC bit while still holding fasync_lock */
- spin_lock(&filp->f_lock);
if (on)
filp->f_flags |= FASYNC;
else
filp->f_flags &= ~FASYNC;
- spin_unlock(&filp->f_lock);
write_unlock_irq(&fasync_lock);
+ spin_unlock(&filp->f_lock);
return result;
}