kernel.git/drivers/usb/gadget/function/f_fs.c, branch linux-6.3.y

usb: gadget: f_fs: Add unbind event before functionfs_unbind

2023-06-09T08:48:15Z

commit efb6b535207395a5c7317993602e2503ca8cb4b3 upstream. While exercising the unbind path, with the current implementation the functionfs_unbind would be calling which waits for the ffs->mutex to be available, however within the same time ffs_ep0_read is invoked & if no setup packets are pending, it will invoke function wait_event_interruptible_exclusive_locked_irq which by definition waits for the ev.count to be increased inside the same mutex for which functionfs_unbind is waiting. This creates deadlock situation because the functionfs_unbind won't get the lock until ev.count is increased which can only happen if the caller ffs_func_unbind can proceed further. Following is the illustration: CPU1 CPU2 ffs_func_unbind() ffs_ep0_read() mutex_lock(ffs->mutex) wait_event(ffs->ev.count) functionfs_unbind() mutex_lock(ffs->mutex) mutex_unlock(ffs->mutex) ffs_event_add() Fix this by moving the event unbind before functionfs_unbind to ensure the ev.count is incrased properly. Fixes: 6a19da111057 ("usb: gadget: f_fs: Prevent race during ffs_ep0_queue_wait") Cc: stable Signed-off-by: Uttkarsh Aggarwal Link: https://lore.kernel.org/r/20230525092854.7992-1-quic_uaggarwa@quicinc.com Signed-off-by: Greg Kroah-Hartman

usb: gadget: f_fs: Fix ffs_epfile_read_iter to handle ITER_UBUF

2023-04-05T17:24:01Z

iov_iter for ffs_epfile_read_iter can be ITER_UBUF with io_uring. In that case dup_iter() does not have to allocate anything and it can return NULL. ffs_epfile_read_iter treats this as a failure and returns -ENOMEM. Fix it by checking if iter_is_ubuf(). Fixes: 1e23db450cff ("io_uring: use iter_ubuf for single range imports") Signed-off-by: Sandeep Dhavale Acked-by: Jens Axboe Link: https://lore.kernel.org/r/20230401060509.3608259-2-dhavale@google.com Signed-off-by: Greg Kroah-Hartman

Merge 6.2-rc7 into usb-next

2023-02-06T07:33:30Z

We need the USB fixes in here, and this resolves a merge conflict with the i915 driver as reported in linux-next Signed-off-by: Greg Kroah-Hartman

usb: gadget: f_fs: Fix unbalanced spinlock in __ffs_ep0_queue_wait

2023-01-24T17:19:39Z

__ffs_ep0_queue_wait executes holding the spinlock of &ffs->ev.waitq.lock and unlocks it after the assignments to usb_request are done. However in the code if the request is already NULL we bail out returning -EINVAL but never unlocked the spinlock. Fix this by adding spin_unlock_irq &ffs->ev.waitq.lock before returning. Fixes: 6a19da111057 ("usb: gadget: f_fs: Prevent race during ffs_ep0_queue_wait") Reviewed-by: John Keeping Signed-off-by: Udipto Goswami Link: https://lore.kernel.org/r/20230124091149.18647-1-quic_ugoswami@quicinc.com Signed-off-by: Greg Kroah-Hartman

Merge 6.2-rc5 into usb-next

2023-01-23T14:38:08Z

We need the USB fixes in here and this resolves merge conflicts as reported in linux-next in the following files: drivers/usb/host/xhci.c drivers/usb/host/xhci.h drivers/usb/typec/ucsi/ucsi.c Reported-by: Stephen Rothwell Signed-off-by: Greg Kroah-Hartman

usb: gadget: f_fs: Ensure ep0req is dequeued before free_request

2023-01-17T16:07:06Z

As per the documentation, function usb_ep_free_request guarantees the request will not be queued or no longer be re-queued (or otherwise used). However, with the current implementation it doesn't make sure that the request in ep0 isn't reused. Fix this by dequeuing the ep0req on functionfs_unbind before freeing the request to align with the definition. Fixes: ddf8abd25994 ("USB: f_fs: the FunctionFS driver") Signed-off-by: Udipto Goswami Tested-by: Krishna Kurapati Link: https://lore.kernel.org/r/20221215052906.8993-3-quic_ugoswami@quicinc.com Signed-off-by: Greg Kroah-Hartman

usb: gadget: f_fs: Prevent race during ffs_ep0_queue_wait

2023-01-17T16:07:06Z

While performing fast composition switch, there is a possibility that the process of ffs_ep0_write/ffs_ep0_read get into a race condition due to ep0req being freed up from functionfs_unbind. Consider the scenario that the ffs_ep0_write calls the ffs_ep0_queue_wait by taking a lock &ffs->ev.waitq.lock. However, the functionfs_unbind isn't bounded so it can go ahead and mark the ep0req to NULL, and since there is no NULL check in ffs_ep0_queue_wait we will end up in use-after-free. Fix this by making a serialized execution between the two functions using a mutex_lock(ffs->mutex). Fixes: ddf8abd25994 ("USB: f_fs: the FunctionFS driver") Signed-off-by: Udipto Goswami Tested-by: Krishna Kurapati Link: https://lore.kernel.org/r/20221215052906.8993-2-quic_ugoswami@quicinc.com Signed-off-by: Greg Kroah-Hartman

usb: gadget: f_fs: use io_data->status consistently

2023-01-06T15:36:52Z

Commit fb1f16d74e26 ("usb: gadget: f_fs: change ep->status safe in ffs_epfile_io()") added a new ffs_io_data::status field to fix lifetime issues in synchronous requests. While there are no similar lifetime issues for asynchronous requests (the separate ep member in ffs_io_data avoids them) using the status field means the USB request can be freed earlier and that there is more consistency between the synchronous and asynchronous I/O paths. Cc: Linyu Yuan Signed-off-by: John Keeping Reviewed-by: Linyu Yuan Link: https://lore.kernel.org/r/20221124170430.3998755-1-john@metanate.com Signed-off-by: Greg Kroah-Hartman

usb: gadget: f_fs: stricter integer overflow checks

2022-09-07T14:23:22Z

This from static analysis. The vla_item() takes a size and adds it to the total. It has a built in integer overflow check so if it encounters an integer overflow anywhere then it records the total as SIZE_MAX. However there is an issue here because the "lang_count*(needed_count+1)" multiplication can overflow. Technically the "lang_count + 1" addition could overflow too, but that would be detected and is harmless. Fix both using the new size_add() and size_mul() functions. Fixes: e6f3862fa1ec ("usb: gadget: FunctionFS: Remove VLAIS usage from gadget code") Signed-off-by: Dan Carpenter Link: https://lore.kernel.org/r/YxDI3lMYomE7WCjn@kili Signed-off-by: Greg Kroah-Hartman

usb: move from strlcpy with unused retval to strscpy

2022-08-19T09:08:54Z

Follow the advice of the below link and prefer 'strscpy' in this subsystem. Conversion is 1:1 because the return value is not used. Generated by a coccinelle script. Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/ Reviewed-by: Richard Leitner Reviewed-by: Laurent Pinchart Acked-by: Shuah Khan Signed-off-by: Wolfram Sang Link: https://lore.kernel.org/r/20220818210116.7517-1-wsa+renesas@sang-engineering.com Signed-off-by: Greg Kroah-Hartman