[PATCH] tipar fixes

- tipar_open(): fix unsigned comparison

- tipar_open(): don't permit NULL pardevice (probably unneeded given the
  above fix).

- tipar_init_module(): handle the situation where parport_register_driver()
  failed to register any devices (parport_register_driver() drops the ->attach
  return value on the floor).

  This probably makes fixes #1 and #2 unneeded.

- tipar_init_module(): fix various error-path resource leaks.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 12 insertions, 3 deletions

diff --git a/drivers/char/tipar.c b/drivers/char/tipar.c
index 41a94bc79f67..eb2eb3e12d6a 100644
--- a/drivers/char/tipar.c
+++ b/drivers/char/tipar.c
@@ -250,12 +250,17 @@ tipar_open(struct inode *inode, struct file *file)
 {
         unsigned int minor = iminor(inode) - TIPAR_MINOR;
 
-        if (minor > tp_count - 1)
+        if (tp_count == 0 || minor > tp_count - 1)
                 return -ENXIO;
 
         if (test_and_set_bit(minor, &opened))
                 return -EBUSY;
 
+        if (!table[minor].dev) {
+                printk(KERN_ERR "%s: NULL device for minor %u\n",
+                                __FUNCTION__, minor);
+                return -ENXIO;
+        }
         parport_claim_or_block(table[minor].dev);
         init_ti_parallel(minor);
         parport_release(table[minor].dev);
@@ -510,16 +515,20 @@ tipar_init_module(void)
                 err = PTR_ERR(tipar_class);
                 goto out_chrdev;
         }
-        if (parport_register_driver(&tipar_driver)) {
+        if (parport_register_driver(&tipar_driver) || tp_count == 0) {
                 printk(KERN_ERR "tipar: unable to register with parport\n");
                 err = -EIO;
-                goto out;
+                goto out_class;
         }
 
         err = 0;
         goto out;
 
+out_class:
+        class_destroy(tipar_class);
+
 out_chrdev:
+        devfs_remove("ticables/par");
         unregister_chrdev(TIPAR_MAJOR, "tipar");
 out:
         return err;