Messages in this thread Patch in this message | | | Subject | Re: [PATCH] USB: Gadget: Composite: Added error handling codes to prevent a memory leak case when the configuration's bind function failed | Date | Fri, 16 Mar 2012 12:14:37 +0100 | From | "Michal Nazarewicz" <> |
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On Fri, 16 Mar 2012 07:27:15 +0100, Yongsul Oh <yongsul96.oh@samsung.com> wrote:
> In some usb gadget driver, (for example usb gadget serial driver(serial.c),
s/usb/USB/g s/gadget driver/composite gadget drivers/
I also don't think the list of examples is necessary here. Maybe just a list file names? My personal opinion, others may disagree though.
Also, comma should go after the closing paren.
> multifunction composite driver(multi,c), nokia composite gadget driver(nokia.c), > HID composite driver(hid.c), CDC composite driver(cdc2.c)..) the configuration's > bind function by called the 'usb_add_config()' has multiple bind config functions
s/by called the/called by the/ s/has/calls/
> for each functionality. (for example cdc2 configuration bind function -'cdc_do_config()'
s/functions for each functionality/functions, one for each USB functionality/
> has two functionality bind config functions -'ecm_bind_config()' & 'acm_bind_config()' > in CDC composite driver.) > > In each functionality bind config function, new instance for each functionality is
s/for each functionality//
> allocated & initialized by 'kzalloc()' and finally the new instance is added by
s/& initialized by 'kzalloc()' and finally the new instance/and/
> 'usb_add_function()'. After 'usb_add_function' state, already created the instance > is only handled by it's configuration & freed from functionality unbind function.
I'm not sure what you meant by this last sentence.
> So, If an error occurred during the second functionality bind config state,
s/If/if/ s/state//
> (for example an error occurred at 'acm_bind_config()' after succeeding of > 'ecm_bind_function()') the created instance by 'acm_bind_config()'
s/the created instance by 'acm_bind_config()'/the instance created by acm_bind_config()/
> cannot be freed. And it makes memory leak situation.
s/freed. And it makes memory leak situation./freed creating a memory leak./
> This patch fixes this issue
s/issue/issue./
Also, drop apostrophes around function names. It looks weird.
> Signed-off-by: Yongsul Oh <yongsul96.oh@samsung.com>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Also, like written previously, I think there might be memory leak in other error recovery paths as well. If you could take a look whether I'm right, that would be awesome.
> --- > drivers/usb/gadget/composite.c | 13 +++++++++++++ > 1 files changed, 13 insertions(+), 0 deletions(-) > > diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c > index baaebf2..4cb1801 100644 > --- a/drivers/usb/gadget/composite.c > +++ b/drivers/usb/gadget/composite.c > @@ -737,6 +737,19 @@ int usb_add_config(struct usb_composite_dev *cdev, > status = bind(config); > if (status < 0) { > + while (!list_empty(&config->functions)) { > + struct usb_function *f; > + > + f = list_first_entry(&config->functions, > + struct usb_function, list); > + list_del(&f->list); > + if (f->unbind) { > + DBG(cdev, "unbind function '%s'/%p\n", > + f->name, f); > + f->unbind(config, f); > + /* may free memory for "f" */ > + } > + } > list_del(&config->list); > config->cdev = NULL; > } else {
-- Best regards, _ _ .o. | Liege of Serenely Enlightened Majesty of o' \,=./ `o ..o | Computer Science, Michał “mina86” Nazarewicz (o o) ooo +----<email/xmpp: mpn@google.com>--------------ooO--(_)--Ooo-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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