From: Jiri Slaby <jslaby@suse.cz>
Date: Wed, 12 Oct 2011 09:32:42 +0000 (+0200)
Subject: TTY: drop driver reference in tty_open fail path
X-Git-Tag: firefly_0821_release~7541^2~2559
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=36174dd629350d0654982977d7795ca28475c16f;p=firefly-linux-kernel-4.4.55.git

TTY: drop driver reference in tty_open fail path

commit c290f8358acaeffd8e0c551ddcc24d1206143376 upstream.

When tty_driver_lookup_tty fails in tty_open, we forget to drop a
reference to the tty driver. This was added by commit 4a2b5fddd5 (Move
tty lookup/reopen to caller).

Fix that by adding tty_driver_kref_put to the fail path.

I will refactor the code later. This is for the ease of backporting to
stable.

Introduced-in: v2.6.28-rc2
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Acked-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index b6f92d3001ad..e9495ed8ec01 100644
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -1872,6 +1872,7 @@ got_driver:
 		if (IS_ERR(tty)) {
 			tty_unlock();
 			mutex_unlock(&tty_mutex);
+			tty_driver_kref_put(driver);
 			return PTR_ERR(tty);
 		}
 	}