From: Johan Hovold johan@kernel.org
stable inclusion from stable-5.10.70 commit 43241a6c6e6c7426fdb92454f9bbc66390d292d7 bugzilla: 182949 https://gitee.com/openeuler/kernel/issues/I4I3GQ
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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commit e8f69b16ee776da88589b5271e3f46020efc8f6c upstream.
If resource allocation and registration fail for a muxed tty device (e.g. if there are no more minor numbers) the driver should not try to deregister the never-registered (or already-deregistered) tty.
Fix up the error handling to avoid dereferencing a NULL pointer when attempting to remove the character device.
Fixes: 72dc1c096c70 ("HSO: add option hso driver") Cc: stable@vger.kernel.org # 2.6.27 Signed-off-by: Johan Hovold johan@kernel.org Signed-off-by: David S. Miller davem@davemloft.net 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/net/usb/hso.c | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-)
diff --git a/drivers/net/usb/hso.c b/drivers/net/usb/hso.c index f269337c82c5..df8d4c1e5be7 100644 --- a/drivers/net/usb/hso.c +++ b/drivers/net/usb/hso.c @@ -2721,14 +2721,14 @@ struct hso_device *hso_create_mux_serial_device(struct usb_interface *interface,
serial = kzalloc(sizeof(*serial), GFP_KERNEL); if (!serial) - goto exit; + goto err_free_dev;
hso_dev->port_data.dev_serial = serial; serial->parent = hso_dev;
if (hso_serial_common_create (serial, 1, CTRL_URB_RX_SIZE, CTRL_URB_TX_SIZE)) - goto exit; + goto err_free_serial;
serial->tx_data_length--; serial->write_data = hso_mux_serial_write_data; @@ -2744,11 +2744,9 @@ struct hso_device *hso_create_mux_serial_device(struct usb_interface *interface, /* done, return it */ return hso_dev;
-exit: - if (serial) { - tty_unregister_device(tty_drv, serial->minor); - kfree(serial); - } +err_free_serial: + kfree(serial); +err_free_dev: kfree(hso_dev); return NULL;