kernel/linux.git/drivers/usb/usb-skeleton.c, branch v6.12.80

usb: add usb_set_intfdata() documentation

2022-11-29T07:56:09+00:00

USB drivers do not need to call usb_set_intfdata(intf, NULL) in their usb_driver::disconnect callback because the core already does it in [1]. However, this fact is widely unknown, c.f.: $ git grep "usb_set_intfdata(.*NULL)" | wc -l 215 Especially, setting the interface to NULL before all action completed can result in a NULL pointer dereference. Not calling usb_set_intfdata() at all in disconnect() is the safest method. Add documentation to usb_set_intfdata() to clarify this point. Also remove the call in usb-skeletion's disconnect() not to confuse the new comers. [1] function usb_unbind_interface() from drivers/usb/core/driver.c Link: https://elixir.bootlin.com/linux/v6.0/source/drivers/usb/core/driver.c#L497 Signed-off-by: Vincent Mailhol Link: https://lore.kernel.org/r/20221128102954.3615579-1-mailhol.vincent@wanadoo.fr Signed-off-by: Greg Kroah-Hartman

usb: usb-skeleton: Update min() to min_t()

2021-10-05T10:56:48+00:00

This patch fixes the checkpatch.pl warning: WARNING: min() should probably be min_t(size_t, count, MAX_TRANSFER) + size_t writesize = min(count, (size_t)MAX_TRANSFER); Signed-off-by: Philipp Hortmann Link: https://lore.kernel.org/r/20210922212037.GA8110@matrix-ESPRIMO-P710 Signed-off-by: Greg Kroah-Hartman

USB: usb-skeleton: drop redundant in-urb check

2019-10-10T10:41:19+00:00

The driver bails out at probe if we can't find a bulk-in endpoint or if we fail to allocate the URB, so drop the check in read(). Signed-off-by: Johan Hovold Link: https://lore.kernel.org/r/20191009170944.30057-4-johan@kernel.org Signed-off-by: Greg Kroah-Hartman

USB: usb-skeleton: fix use-after-free after driver unbind

2019-10-10T10:41:19+00:00

The driver failed to stop its read URB on disconnect, something which could lead to a use-after-free in the completion handler after driver unbind in case the character device has been closed. Fixes: e7389cc9a7ff ("USB: skel_read really sucks royally") Signed-off-by: Johan Hovold Link: https://lore.kernel.org/r/20191009170944.30057-3-johan@kernel.org Signed-off-by: Greg Kroah-Hartman

USB: usb-skeleton: fix NULL-deref on disconnect

2019-10-10T10:41:18+00:00

The driver was using its struct usb_interface pointer as an inverted disconnected flag and was setting it to NULL before making sure all completion handlers had run. This could lead to NULL-pointer dereferences in the dev_err() statements in the completion handlers which relies on said pointer. Fix this by using a dedicated disconnected flag. Note that this is also addresses a NULL-pointer dereference at release() and a struct usb_interface reference leak introduced by a recent runtime PM fix, which depends on and should have been submitted together with this patch. Fixes: 4212cd74ca6f ("USB: usb-skeleton.c: remove err() usage") Fixes: 5c290a5e42c3 ("USB: usb-skeleton: fix runtime PM after driver unbind") Cc: stable Signed-off-by: Johan Hovold Link: https://lore.kernel.org/r/20191009170944.30057-2-johan@kernel.org Signed-off-by: Greg Kroah-Hartman

USB: usb-skeleton: fix runtime PM after driver unbind

2019-10-04T12:38:45+00:00

Since commit c2b71462d294 ("USB: core: Fix bug caused by duplicate interface PM usage counter") USB drivers must always balance their runtime PM gets and puts, including when the driver has already been unbound from the interface. Leaving the interface with a positive PM usage counter would prevent a later bound driver from suspending the device. Fixes: c2b71462d294 ("USB: core: Fix bug caused by duplicate interface PM usage counter") Cc: stable Signed-off-by: Johan Hovold Link: https://lore.kernel.org/r/20191001084908.2003-2-johan@kernel.org Signed-off-by: Greg Kroah-Hartman

usb: usb-skeleton: make comment block in line with coding style

2019-08-21T16:57:36+00:00

Comment block was not in accordance with coding style. Fixes two checkpatch warnings: WARNING: Block comments use * on subsequent lines WARNING: Block comments use a trailing */ on a separate line Signed-off-by: Jacob Huisman Link: https://lore.kernel.org/r/20190815174210.580-1-jacobhuisman@kernelthusiast.com Signed-off-by: Greg Kroah-Hartman

usb: usb-skeleton: use irqsave() in USB's complete callback

2018-06-28T10:36:06+00:00

The USB completion callback does not disable interrupts while acquiring the lock. We want to remove the local_irq_disable() invocation from __usb_hcd_giveback_urb() and therefore it is required for the callback handler to disable the interrupts while acquiring the lock. The callback may be invoked either in IRQ or BH context depending on the USB host controller. Use the _irqsave() variant of the locking primitives. Signed-off-by: John Ogness Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Greg Kroah-Hartman

usb: usb-skeleton: make MODULE_LICENSE and SPDX tag match

2018-03-06T17:42:07+00:00

GPL v2 is the original license according to the old license text. See f64cdd0e94f1faf3b7f2b03af71f70dc6d8da0c2. Signed-off-by: Marcus Folkesson Signed-off-by: Greg Kroah-Hartman

USB: usb-skeleton: Remove redundant license text

2017-11-04T10:55:39+00:00

Now that the SPDX tag is in all USB files, that identifies the license in a specific and legally-defined manner. So the extra GPL text wording can be removed as it is no longer needed at all. This is done on a quest to remove the 700+ different ways that files in the kernel describe the GPL license text. And there's unneeded stuff like the address (sometimes incorrect) for the FSF which is never needed. No copyright headers or other non-license-description text was removed. Signed-off-by: Greg Kroah-Hartman