#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);
}
return ret;
}
-#define SETFL_MASK (O_APPEND | O_NONBLOCK | O_NDELAY | FASYNC | O_DIRECT | O_NOATIME)
+#define SETFL_MASK (O_APPEND | O_NONBLOCK | O_NDELAY | O_DIRECT | O_NOATIME)
static int setfl(int fd, struct file * filp, unsigned long arg)
{
return error;
/*
- * We still need a lock here for now to keep multiple FASYNC calls
- * from racing with each other.
+ * ->fasync() is responsible for setting the FASYNC bit.
*/
- lock_kernel();
- if ((arg ^ filp->f_flags) & FASYNC) {
- if (filp->f_op && filp->f_op->fasync) {
- error = filp->f_op->fasync(fd, filp, (arg & FASYNC) != 0);
- if (error < 0)
- goto out;
- }
+ if (((arg ^ filp->f_flags) & FASYNC) && filp->f_op &&
+ filp->f_op->fasync) {
+ 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);
spin_unlock(&filp->f_lock);
+
out:
- unlock_kernel();
return error;
}
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)
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)
{
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;
}
static void send_sigio_to_task(struct task_struct *p,
- struct fown_struct *fown,
- int fd,
- int reason)
+ struct fown_struct *fown,
+ int fd, int reason, int group)
{
- 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 (!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);
}
}
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:
}
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)
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;
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:
static struct kmem_cache *fasync_cache __read_mostly;
/*
- * fasync_helper() is used by some character device drivers (mainly mice)
+ * 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.
*/
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:
+ if (on)
+ filp->f_flags |= FASYNC;
+ else
+ filp->f_flags &= ~FASYNC;
write_unlock_irq(&fasync_lock);
+ spin_unlock(&filp->f_lock);
return result;
}