From: Johan Hovold johan@kernel.org
stable inclusion from stable-5.10.71 commit 7cea848678470daadbfdaa6a112b823c290f900c bugzilla: 182981 https://gitee.com/openeuler/kernel/issues/I4I3KD
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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commit bb8a4fcb2136508224c596a7e665bdba1d7c3c27 upstream.
A reference to the carrier module was taken on every open but was only released once when the final reference to the tty struct was dropped.
Fix this by taking the module reference and initialising the tty driver data when installing the tty.
Fixes: 82a82340bab6 ("ipoctal: get carrier driver to avoid rmmod") Cc: stable@vger.kernel.org # 3.18 Cc: Federico Vaga federico.vaga@cern.ch Acked-by: Samuel Iglesias Gonsalvez siglesias@igalia.com Signed-off-by: Johan Hovold johan@kernel.org Link: https://lore.kernel.org/r/20210917114622.5412-6-johan@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Chen Jun chenjun102@huawei.com Acked-by: Weilong Chen chenweilong@huawei.com
Signed-off-by: Chen Jun chenjun102@huawei.com --- drivers/ipack/devices/ipoctal.c | 29 +++++++++++++++++++++-------- 1 file changed, 21 insertions(+), 8 deletions(-)
diff --git a/drivers/ipack/devices/ipoctal.c b/drivers/ipack/devices/ipoctal.c index 9e6e105e35aa..1f7512c991a3 100644 --- a/drivers/ipack/devices/ipoctal.c +++ b/drivers/ipack/devices/ipoctal.c @@ -84,22 +84,34 @@ static int ipoctal_port_activate(struct tty_port *port, struct tty_struct *tty) return 0; }
-static int ipoctal_open(struct tty_struct *tty, struct file *file) +static int ipoctal_install(struct tty_driver *driver, struct tty_struct *tty) { struct ipoctal_channel *channel = dev_get_drvdata(tty->dev); struct ipoctal *ipoctal = chan_to_ipoctal(channel, tty->index); - int err; - - tty->driver_data = channel; + int res;
if (!ipack_get_carrier(ipoctal->dev)) return -EBUSY;
- err = tty_port_open(&channel->tty_port, tty, file); - if (err) - ipack_put_carrier(ipoctal->dev); + res = tty_standard_install(driver, tty); + if (res) + goto err_put_carrier; + + tty->driver_data = channel; + + return 0; + +err_put_carrier: + ipack_put_carrier(ipoctal->dev); + + return res; +} + +static int ipoctal_open(struct tty_struct *tty, struct file *file) +{ + struct ipoctal_channel *channel = tty->driver_data;
- return err; + return tty_port_open(&channel->tty_port, tty, file); }
static void ipoctal_reset_stats(struct ipoctal_stats *stats) @@ -665,6 +677,7 @@ static void ipoctal_cleanup(struct tty_struct *tty)
static const struct tty_operations ipoctal_fops = { .ioctl = NULL, + .install = ipoctal_install, .open = ipoctal_open, .close = ipoctal_close, .write = ipoctal_write_tty,