| From cd20d59291d1790dc74248476e928f57fc455189 Mon Sep 17 00:00:00 2001 |
| From: Johan Hovold <johan@kernel.org> |
| Date: Fri, 17 Sep 2021 13:46:19 +0200 |
| Subject: ipack: ipoctal: fix tty-registration error handling |
| |
| From: Johan Hovold <johan@kernel.org> |
| |
| commit cd20d59291d1790dc74248476e928f57fc455189 upstream. |
| |
| Registration of the ipoctal tty devices is unlikely to fail, but if it |
| ever does, make sure not to deregister a never registered tty device |
| (and dereference a NULL pointer) when the driver is later unbound. |
| |
| Fixes: 2afb41d9d30d ("Staging: ipack/devices/ipoctal: Check tty_register_device return value.") |
| Cc: stable@vger.kernel.org # 3.7 |
| Acked-by: Samuel Iglesias Gonsalvez <siglesias@igalia.com> |
| Signed-off-by: Johan Hovold <johan@kernel.org> |
| Link: https://lore.kernel.org/r/20210917114622.5412-4-johan@kernel.org |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| drivers/ipack/devices/ipoctal.c | 7 +++++++ |
| 1 file changed, 7 insertions(+) |
| |
| --- a/drivers/ipack/devices/ipoctal.c |
| +++ b/drivers/ipack/devices/ipoctal.c |
| @@ -35,6 +35,7 @@ struct ipoctal_channel { |
| unsigned int pointer_read; |
| unsigned int pointer_write; |
| struct tty_port tty_port; |
| + bool tty_registered; |
| union scc2698_channel __iomem *regs; |
| union scc2698_block __iomem *block_regs; |
| unsigned int board_id; |
| @@ -399,9 +400,11 @@ static int ipoctal_inst_slot(struct ipoc |
| i, NULL, channel, NULL); |
| if (IS_ERR(tty_dev)) { |
| dev_err(&ipoctal->dev->dev, "Failed to register tty device.\n"); |
| + tty_port_free_xmit_buf(&channel->tty_port); |
| tty_port_destroy(&channel->tty_port); |
| continue; |
| } |
| + channel->tty_registered = true; |
| } |
| |
| /* |
| @@ -702,6 +705,10 @@ static void __ipoctal_remove(struct ipoc |
| |
| for (i = 0; i < NR_CHANNELS; i++) { |
| struct ipoctal_channel *channel = &ipoctal->channel[i]; |
| + |
| + if (!channel->tty_registered) |
| + continue; |
| + |
| tty_unregister_device(ipoctal->tty_drv, i); |
| tty_port_free_xmit_buf(&channel->tty_port); |
| tty_port_destroy(&channel->tty_port); |