The patch below does not apply to the 4.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From e7694cb6998379341fd9bf3bd62b48c4e6a79385 Mon Sep 17 00:00:00 2001

From: Zhang Qilong zhangqilong3@huawei.com Date: Tue, 17 Nov 2020 10:16:28 +0800 Subject: [PATCH] usb: gadget: f_midi: Fix memleak in f_midi_alloc

In the error path, if midi is not null, we should free the midi->id if necessary to prevent memleak.

Fixes: b85e9de9e818d ("usb: gadget: f_midi: convert to new function interface with backward compatibility") Reported-by: Hulk Robot hulkci@huawei.com Signed-off-by: Zhang Qilong zhangqilong3@huawei.com Link: https://lore.kernel.org/r/20201117021629.1470544-2-zhangqilong3@huawei.com Cc: stable stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

diff --git a/drivers/usb/gadget/function/f_midi.c b/drivers/usb/gadget/function/f_midi.c index 85cb15734aa8..19d97940eeb9 100644 --- a/drivers/usb/gadget/function/f_midi.c +++ b/drivers/usb/gadget/function/f_midi.c @@ -1315,7 +1315,7 @@ static struct usb_function *f_midi_alloc(struct usb_function_instance *fi) midi->id = kstrdup(opts->id, GFP_KERNEL); if (opts->id && !midi->id) { status = -ENOMEM; - goto setup_fail; + goto midi_free; } midi->in_ports = opts->in_ports; midi->out_ports = opts->out_ports; @@ -1327,7 +1327,7 @@ static struct usb_function *f_midi_alloc(struct usb_function_instance *fi)

status = kfifo_alloc(&midi->in_req_fifo, midi->qlen, GFP_KERNEL); if (status) - goto setup_fail; + goto midi_free;

spin_lock_init(&midi->transmit_lock);

@@ -1343,9 +1343,13 @@ static struct usb_function *f_midi_alloc(struct usb_function_instance *fi)

return &midi->func;

+midi_free: + if (midi) + kfree(midi->id); + kfree(midi); setup_fail: mutex_unlock(&opts->lock); - kfree(midi); + return ERR_PTR(status); }