ALSA: off by one bug in snd_riptide_joystick_probe() (e4940626) · Commits · 戴 / test

The problem here is that we check: if (dev >= SNDRV_CARDS) Then we increment "dev". if (!joystick_port[dev++]) Then we use it as an offset into a array with SNDRV_CARDS elements. if (!request_region(joystick_port[dev], 8, "Riptide gameport")) { This has 3 effects: 1) If you use the module option to specify the joystick port then it has to be shifted one space over. 2) The wrong error message will be printed on failure if you have over 32 cards. 3) Static checkers will correctly complain that are off by one. Fixes: ('ALSA: riptide - Fix joystick resource handling') Signed-off-by:

Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by:

Takashi Iwai <tiwai@suse.de>

sound/pci/riptide/riptide.c

+19 −8

Original line number	Diff line number	Diff line
		@@ -2011,32 +2011,43 @@ snd_riptide_joystick_probe(struct pci_dev pci, const struct pci_device_id id)
		{
		static int dev;
		struct gameport *gameport;
		int ret;

		if (dev >= SNDRV_CARDS)
		return -ENODEV;

		if (!enable[dev]) {
		dev++;
		return -ENOENT;
		ret = -ENOENT;
		goto inc_dev;
		}

		if (!joystick_port[dev++])
		return 0;
		if (!joystick_port[dev]) {
		ret = 0;
		goto inc_dev;
		}

		gameport = gameport_allocate_port();
		if (!gameport)
		return -ENOMEM;
		if (!gameport) {
		ret = -ENOMEM;
		goto inc_dev;
		}
		if (!request_region(joystick_port[dev], 8, "Riptide gameport")) {
		snd_printk(KERN_WARNING
		"Riptide: cannot grab gameport 0x%x\n",
		joystick_port[dev]);
		gameport_free_port(gameport);
		return -EBUSY;
		ret = -EBUSY;
		goto inc_dev;
		}

		gameport->io = joystick_port[dev];
		gameport_register_port(gameport);
		pci_set_drvdata(pci, gameport);
		return 0;

		ret = 0;
		inc_dev:
		dev++;
		return ret;
		}

		static void snd_riptide_joystick_remove(struct pci_dev *pci)

Admin message