kernel/linux.git/drivers/usb/core/buffer.c, branch v6.1.168

usb: usbfs: Enforce page requirements for mmap

2023-06-14T09:15:29+00:00

commit 0143d148d1e882fb1538dc9974c94d63961719b9 upstream. The current implementation of usbdev_mmap uses usb_alloc_coherent to allocate memory pages that will later be mapped into the user space. Meanwhile, usb_alloc_coherent employs three different methods to allocate memory, as outlined below: * If hcd->localmem_pool is non-null, it uses gen_pool_dma_alloc to allocate memory; * If DMA is not available, it uses kmalloc to allocate memory; * Otherwise, it uses dma_alloc_coherent. However, it should be noted that gen_pool_dma_alloc does not guarantee that the resulting memory will be page-aligned. Furthermore, trying to map slab pages (i.e., memory allocated by kmalloc) into the user space is not resonable and can lead to problems, such as a type confusion bug when PAGE_TABLE_CHECK=y [1]. To address these issues, this patch introduces hcd_alloc_coherent_pages, which addresses the above two problems. Specifically, hcd_alloc_coherent_pages uses gen_pool_dma_alloc_align instead of gen_pool_dma_alloc to ensure that the memory is page-aligned. To replace kmalloc, hcd_alloc_coherent_pages directly allocates pages by calling __get_free_pages. Reported-by: syzbot+fcf1a817ceb50935ce99@syzkaller.appspotmail.comm Closes: https://lore.kernel.org/lkml/000000000000258e5e05fae79fc1@google.com/ [1] Fixes: f7d34b445abc ("USB: Add support for usbfs zerocopy.") Fixes: ff2437befd8f ("usb: host: Fix excessive alignment restriction for local memory allocations") Cc: stable@vger.kernel.org Signed-off-by: Ruihan Li Acked-by: Alan Stern Link: https://lore.kernel.org/r/20230515130958.32471-2-lrh2000@pku.edu.cn Signed-off-by: Greg Kroah-Hartman Signed-off-by: Greg Kroah-Hartman

usb: core: Replace in_interrupt() in comments

2020-10-28T11:32:59+00:00

The usage of in_interrupt() in drivers is phased out for various reasons. Various comments use !in_interrupt() to describe calling context for functions which might sleep. That's wrong because the calling context has to be preemptible task context, which is not what !in_interrupt() describes. Replace !in_interrupt() with more accurate plain text descriptions. The comment for usb_hcd_poll_rh_status() is misleading as this function is called from all kinds of contexts including preemptible task context. Remove it as there is obviously no restriction. Signed-off-by: Ahmed S. Darwish Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Thomas Gleixner Acked-by: Alan Stern Cc: linux-usb@vger.kernel.org Link: https://lore.kernel.org/r/20201019101110.851821025@linutronix.de Signed-off-by: Greg Kroah-Hartman

usb: add a hcd_uses_dma helper

2019-08-15T13:18:05+00:00

The USB buffer allocation code is the only place in the usb core (and in fact the whole kernel) that uses is_device_dma_capable, while the URB mapping code uses the uses_dma flag in struct usb_bus. Switch the buffer allocation to use the uses_dma flag used by the rest of the USB code, and create a helper in hcd.h that checks this flag as well as the CONFIG_HAS_DMA to simplify the caller a bit. Signed-off-by: Christoph Hellwig Link: https://lore.kernel.org/r/20190811080520.21712-3-hch@lst.de Signed-off-by: Greg Kroah-Hartman

usb: don't create dma pools for HCDs with a localmem_pool

2019-08-15T13:17:07+00:00

If the HCD provides a localmem pool we will never use the DMA pools, so don't create them. Fixes: b0310c2f09bb ("USB: use genalloc for USB HCs with local memory") Signed-off-by: Christoph Hellwig Link: https://lore.kernel.org/r/20190811080520.21712-2-hch@lst.de Signed-off-by: Greg Kroah-Hartman

USB: drop HCD_LOCAL_MEM flag

2019-06-03T14:00:08+00:00

With the addition of the local memory allocator, the HCD_LOCAL_MEM flag can be dropped and the checks against it replaced with a check for the localmem_pool ptr being initialized. Signed-off-by: Laurentiu Tudor Tested-by: Fredrik Noring Reviewed-by: Greg Kroah-Hartman Signed-off-by: Christoph Hellwig

USB: use genalloc for USB HCs with local memory

2019-06-03T14:00:07+00:00

For HCs that have local memory, replace the current DMA API usage with a genalloc generic allocator to manage the mappings for these devices. To help users, introduce a new HCD API, usb_hcd_setup_local_mem() that will setup up the genalloc backing up the device local memory. It will be used in subsequent patches. This is in preparation for dropping the existing "coherent" dma mem declaration APIs. The current implementation was relying on a short circuit in the DMA API that in the end, was acting as an allocator for these type of devices. Signed-off-by: Laurentiu Tudor Tested-by: Fredrik Noring Reviewed-by: Greg Kroah-Hartman Signed-off-by: Christoph Hellwig

USB: Removing NULL check for pool since dma_pool_destroy is safe

2018-09-10T18:01:04+00:00

Removing NULL check for pool since dma_pool_destroy is safe Signed-off-by: Salil Kapur Signed-off-by: Greg Kroah-Hartman

USB: core: move existing SPDX tags to top of the file

2017-11-03T09:12:26+00:00

To match the rest of the kernel, the SPDX tags for the drivers/usb/core/ files are moved to the first line of the file. This makes it more obvious the tag is present as well as making it match the other 12k files in the tree with this location. It also uses // to match the "expected style" as well. Signed-off-by: Greg Kroah-Hartman

usb: separate out sysdev pointer from usb_bus

2017-03-23T07:20:21+00:00

For xhci-hcd platform device, all the DMA parameters are not configured properly, notably dma ops for dwc3 devices. The idea here is that you pass in the parent of_node along with the child device pointer, so it would behave exactly like the parent already does. The difference is that it also handles all the other attributes besides the mask. sysdev will represent the physical device, as seen from firmware or bus.Splitting the usb_bus->controller field into the Linux-internal device (used for the sysfs hierarchy, for printks and for power management) and a new pointer (used for DMA, DT enumeration and phy lookup) probably covers all that we really need. Signed-off-by: Arnd Bergmann Signed-off-by: Sriram Dash Tested-by: Baolin Wang Tested-by: Brian Norris Tested-by: Alexander Sverdlin Tested-by: Vivek Gautam Signed-off-by: Mathias Nyman Signed-off-by: Peter Chen Cc: Felipe Balbi Cc: Grygorii Strashko Cc: Sinjan Kumar Cc: David Fisher Cc: Catalin Marinas Cc: "Thang Q. Nguyen" Cc: Yoshihiro Shimoda Cc: Stephen Boyd Cc: Bjorn Andersson Cc: Ming Lei Cc: Jon Masters Cc: Dann Frazier Cc: Peter Chen Cc: Leo Li Signed-off-by: Greg Kroah-Hartman

USB: core: add missing license information to some files

2016-10-29T16:51:56+00:00

Some of the USB core files were missing explicit license information. As all files in the kernel tree are implicitly licensed under the GPLv2-only, be explicit in case someone get confused looking at individual files by using the SPDX nomenclature. Signed-off-by: Greg Kroah-Hartman