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Diffstat (limited to 'fs/locks.c')
-rw-r--r--fs/locks.c91
1 files changed, 57 insertions, 34 deletions
diff --git a/fs/locks.c b/fs/locks.c
index 3fa6a7ce57a..11956b6179f 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -1276,7 +1276,7 @@ int fcntl_getlease(struct file *filp)
*/
static int __setlease(struct file *filp, long arg, struct file_lock **flp)
{
- struct file_lock *fl, **before, **my_before = NULL, *lease = *flp;
+ struct file_lock *fl, **before, **my_before = NULL, *lease;
struct dentry *dentry = filp->f_dentry;
struct inode *inode = dentry->d_inode;
int error, rdlease_count = 0, wrlease_count = 0;
@@ -1287,6 +1287,8 @@ static int __setlease(struct file *filp, long arg, struct file_lock **flp)
if (!flp || !(*flp) || !(*flp)->fl_lmops || !(*flp)->fl_lmops->fl_break)
goto out;
+ lease = *flp;
+
error = -EAGAIN;
if ((arg == F_RDLCK) && (atomic_read(&inode->i_writecount) > 0))
goto out;
@@ -1548,6 +1550,8 @@ int fcntl_getlk(struct file *filp, struct flock __user *l)
if (filp->f_op && filp->f_op->lock) {
error = filp->f_op->lock(filp, F_GETLK, &file_lock);
+ if (file_lock.fl_ops && file_lock.fl_ops->fl_release_private)
+ file_lock.fl_ops->fl_release_private(&file_lock);
if (error < 0)
goto out;
else
@@ -1587,7 +1591,8 @@ out:
/* Apply the lock described by l to an open file descriptor.
* This implements both the F_SETLK and F_SETLKW commands of fcntl().
*/
-int fcntl_setlk(struct file *filp, unsigned int cmd, struct flock __user *l)
+int fcntl_setlk(unsigned int fd, struct file *filp, unsigned int cmd,
+ struct flock __user *l)
{
struct file_lock *file_lock = locks_alloc_lock();
struct flock flock;
@@ -1616,6 +1621,7 @@ int fcntl_setlk(struct file *filp, unsigned int cmd, struct flock __user *l)
goto out;
}
+again:
error = flock_to_posix_lock(filp, file_lock, &flock);
if (error)
goto out;
@@ -1644,25 +1650,33 @@ int fcntl_setlk(struct file *filp, unsigned int cmd, struct flock __user *l)
if (error)
goto out;
- if (filp->f_op && filp->f_op->lock != NULL) {
+ if (filp->f_op && filp->f_op->lock != NULL)
error = filp->f_op->lock(filp, cmd, file_lock);
- goto out;
- }
+ else {
+ for (;;) {
+ error = __posix_lock_file(inode, file_lock);
+ if ((error != -EAGAIN) || (cmd == F_SETLK))
+ break;
+ error = wait_event_interruptible(file_lock->fl_wait,
+ !file_lock->fl_next);
+ if (!error)
+ continue;
- for (;;) {
- error = __posix_lock_file(inode, file_lock);
- if ((error != -EAGAIN) || (cmd == F_SETLK))
+ locks_delete_block(file_lock);
break;
- error = wait_event_interruptible(file_lock->fl_wait,
- !file_lock->fl_next);
- if (!error)
- continue;
+ }
+ }
- locks_delete_block(file_lock);
- break;
+ /*
+ * Attempt to detect a close/fcntl race and recover by
+ * releasing the lock that was just acquired.
+ */
+ if (!error && fcheck(fd) != filp && flock.l_type != F_UNLCK) {
+ flock.l_type = F_UNLCK;
+ goto again;
}
- out:
+out:
locks_free_lock(file_lock);
return error;
}
@@ -1690,6 +1704,8 @@ int fcntl_getlk64(struct file *filp, struct flock64 __user *l)
if (filp->f_op && filp->f_op->lock) {
error = filp->f_op->lock(filp, F_GETLK, &file_lock);
+ if (file_lock.fl_ops && file_lock.fl_ops->fl_release_private)
+ file_lock.fl_ops->fl_release_private(&file_lock);
if (error < 0)
goto out;
else
@@ -1718,7 +1734,8 @@ out:
/* Apply the lock described by l to an open file descriptor.
* This implements both the F_SETLK and F_SETLKW commands of fcntl().
*/
-int fcntl_setlk64(struct file *filp, unsigned int cmd, struct flock64 __user *l)
+int fcntl_setlk64(unsigned int fd, struct file *filp, unsigned int cmd,
+ struct flock64 __user *l)
{
struct file_lock *file_lock = locks_alloc_lock();
struct flock64 flock;
@@ -1747,6 +1764,7 @@ int fcntl_setlk64(struct file *filp, unsigned int cmd, struct flock64 __user *l)
goto out;
}
+again:
error = flock64_to_posix_lock(filp, file_lock, &flock);
if (error)
goto out;
@@ -1775,22 +1793,30 @@ int fcntl_setlk64(struct file *filp, unsigned int cmd, struct flock64 __user *l)
if (error)
goto out;
- if (filp->f_op && filp->f_op->lock != NULL) {
+ if (filp->f_op && filp->f_op->lock != NULL)
error = filp->f_op->lock(filp, cmd, file_lock);
- goto out;
- }
+ else {
+ for (;;) {
+ error = __posix_lock_file(inode, file_lock);
+ if ((error != -EAGAIN) || (cmd == F_SETLK64))
+ break;
+ error = wait_event_interruptible(file_lock->fl_wait,
+ !file_lock->fl_next);
+ if (!error)
+ continue;
- for (;;) {
- error = __posix_lock_file(inode, file_lock);
- if ((error != -EAGAIN) || (cmd == F_SETLK64))
+ locks_delete_block(file_lock);
break;
- error = wait_event_interruptible(file_lock->fl_wait,
- !file_lock->fl_next);
- if (!error)
- continue;
+ }
+ }
- locks_delete_block(file_lock);
- break;
+ /*
+ * Attempt to detect a close/fcntl race and recover by
+ * releasing the lock that was just acquired.
+ */
+ if (!error && fcheck(fd) != filp && flock.l_type != F_UNLCK) {
+ flock.l_type = F_UNLCK;
+ goto again;
}
out:
@@ -1873,6 +1899,8 @@ void locks_remove_flock(struct file *filp)
.fl_end = OFFSET_MAX,
};
filp->f_op->flock(filp, F_SETLKW, &fl);
+ if (fl.fl_ops && fl.fl_ops->fl_release_private)
+ fl.fl_ops->fl_release_private(&fl);
}
lock_kernel();
@@ -1880,12 +1908,7 @@ void locks_remove_flock(struct file *filp)
while ((fl = *before) != NULL) {
if (fl->fl_file == filp) {
- /*
- * We might have a POSIX lock that was created at the same time
- * the filp was closed for the last time. Just remove that too,
- * regardless of ownership, since nobody can own it.
- */
- if (IS_FLOCK(fl) || IS_POSIX(fl)) {
+ if (IS_FLOCK(fl)) {
locks_delete_lock(before);
continue;
}
generated by cgit v1.2.3 (git 2.25.1) at 2025-01-06 16:59:17 +0000