kernel.git/drivers/usb/gadget/function/f_fs.c, branch linux-5.3.y

usb: gadget: Zero ffs_io_data

2019-06-18T08:58:29Z

In some cases the "Allocate & copy" block in ffs_epfile_io() is not executed. Consequently, in such a case ffs_alloc_buffer() is never called and struct ffs_io_data is not initialized properly. This in turn leads to problems when ffs_free_buffer() is called at the end of ffs_epfile_io(). This patch uses kzalloc() instead of kmalloc() in the aio case and memset() in non-aio case to properly initialize struct ffs_io_data. Signed-off-by: Andrzej Pietrasiewicz Signed-off-by: Felipe Balbi

usb: gadget: f_fs: data_len used before properly set

2019-06-18T08:58:28Z

The following line of code in function ffs_epfile_io is trying to set flag io_data->use_sg in case buffer required is larger than one page. io_data->use_sg = gadget->sg_supported && data_len > PAGE_SIZE; However at this point of time the variable data_len has not been set to the proper buffer size yet. The consequence is that io_data->use_sg is always set regardless what buffer size really is, because the condition (data_len > PAGE_SIZE) is effectively an unsigned comparison between -EINVAL and PAGE_SIZE which would always result in TRUE. Fixes: 772a7a724f69 ("usb: gadget: f_fs: Allow scatter-gather buffers") Signed-off-by: Fei Yang Cc: stable Signed-off-by: Felipe Balbi

usb: gadget: f_fs: don't free buffer prematurely

2019-05-03T06:12:53Z

The following kernel panic happens due to the io_data buffer gets deallocated before the async io is completed. Add a check for the case where io_data buffer should be deallocated by ffs_user_copy_worker. [ 41.663334] BUG: unable to handle kernel NULL pointer dereference at 0000000000000048 [ 41.672099] #PF error: [normal kernel read fault] [ 41.677356] PGD 20c974067 P4D 20c974067 PUD 20c973067 PMD 0 [ 41.683687] Oops: 0000 [#1] PREEMPT SMP [ 41.687976] CPU: 1 PID: 7 Comm: kworker/u8:0 Tainted: G U 5.0.0-quilt-2e5dc0ac-00790-gd8c79f2-dirty #2 [ 41.705309] Workqueue: adb ffs_user_copy_worker [ 41.705316] RIP: 0010:__vunmap+0x2a/0xc0 [ 41.705318] Code: 0f 1f 44 00 00 48 85 ff 0f 84 87 00 00 00 55 f7 c7 ff 0f 00 00 48 89 e5 41 55 41 89 f5 41 54 53 48 89 fb 75 71 e8 56 d7 ff ff <4c> 8b 60 48 4d 85 e4 74 76 48 89 df e8 25 ff ff ff 45 85 ed 74 46 [ 41.705320] RSP: 0018:ffffbc3a40053df0 EFLAGS: 00010286 [ 41.705322] RAX: 0000000000000000 RBX: ffffbc3a406f1000 RCX: 0000000000000000 [ 41.705323] RDX: 0000000000000001 RSI: 0000000000000001 RDI: 00000000ffffffff [ 41.705324] RBP: ffffbc3a40053e08 R08: 000000000001fb79 R09: 0000000000000037 [ 41.705325] R10: ffffbc3a40053b68 R11: ffffbc3a40053cad R12: fffffffffffffff2 [ 41.705326] R13: 0000000000000001 R14: 0000000000000000 R15: ffffffffffffffff [ 41.705328] FS: 0000000000000000(0000) GS:ffff9e2977a80000(0000) knlGS:0000000000000000 [ 41.705329] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 41.705330] CR2: 0000000000000048 CR3: 000000020c994000 CR4: 00000000003406e0 [ 41.705331] Call Trace: [ 41.705338] vfree+0x50/0xb0 [ 41.705341] ffs_user_copy_worker+0xe9/0x1c0 [ 41.705344] process_one_work+0x19f/0x3e0 [ 41.705348] worker_thread+0x3f/0x3b0 [ 41.829766] kthread+0x12b/0x150 [ 41.833371] ? process_one_work+0x3e0/0x3e0 [ 41.838045] ? kthread_create_worker_on_cpu+0x70/0x70 [ 41.843695] ret_from_fork+0x3a/0x50 [ 41.847689] Modules linked in: hci_uart bluetooth ecdh_generic rfkill_gpio dwc3_pci dwc3 snd_usb_audio mei_me tpm_crb snd_usbmidi_lib xhci_pci xhci_hcd mei tpm snd_hwdep cfg80211 snd_soc_skl snd_soc_skl_ipc snd_soc_sst_ipc snd_soc_sst_dsp snd_hda_ext_core snd_hda_core videobuf2_dma_sg crlmodule [ 41.876880] CR2: 0000000000000048 [ 41.880584] ---[ end trace 2bc4addff0f2e673 ]--- [ 41.891346] RIP: 0010:__vunmap+0x2a/0xc0 [ 41.895734] Code: 0f 1f 44 00 00 48 85 ff 0f 84 87 00 00 00 55 f7 c7 ff 0f 00 00 48 89 e5 41 55 41 89 f5 41 54 53 48 89 fb 75 71 e8 56 d7 ff ff <4c> 8b 60 48 4d 85 e4 74 76 48 89 df e8 25 ff ff ff 45 85 ed 74 46 [ 41.916740] RSP: 0018:ffffbc3a40053df0 EFLAGS: 00010286 [ 41.922583] RAX: 0000000000000000 RBX: ffffbc3a406f1000 RCX: 0000000000000000 [ 41.930563] RDX: 0000000000000001 RSI: 0000000000000001 RDI: 00000000ffffffff [ 41.938540] RBP: ffffbc3a40053e08 R08: 000000000001fb79 R09: 0000000000000037 [ 41.946520] R10: ffffbc3a40053b68 R11: ffffbc3a40053cad R12: fffffffffffffff2 [ 41.954502] R13: 0000000000000001 R14: 0000000000000000 R15: ffffffffffffffff [ 41.962482] FS: 0000000000000000(0000) GS:ffff9e2977a80000(0000) knlGS:0000000000000000 [ 41.971536] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 41.977960] CR2: 0000000000000048 CR3: 000000020c994000 CR4: 00000000003406e0 [ 41.985930] Kernel panic - not syncing: Fatal exception [ 41.991817] Kernel Offset: 0x16000000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff) [ 42.009525] Rebooting in 10 seconds.. [ 52.014376] ACPI MEMORY or I/O RESET_REG. Fixes: 772a7a724f69 ("usb: gadget: f_fs: Allow scatter-gather buffers") Signed-off-by: Fei Yang Reviewed-by: Manu Gautam Tested-by: John Stultz Signed-off-by: Felipe Balbi

usb: f_fs: Avoid crash due to out-of-scope stack ptr access

2019-02-11T09:11:29Z

Since the 5.0 merge window opened, I've been seeing frequent crashes on suspend and reboot with the trace: [ 36.911170] Unable to handle kernel paging request at virtual address ffffff801153d660 [ 36.912769] Unable to handle kernel paging request at virtual address ffffff800004b564 ... [ 36.950666] Call trace: [ 36.950670] queued_spin_lock_slowpath+0x1cc/0x2c8 [ 36.950681] _raw_spin_lock_irqsave+0x64/0x78 [ 36.950692] complete+0x28/0x70 [ 36.950703] ffs_epfile_io_complete+0x3c/0x50 [ 36.950713] usb_gadget_giveback_request+0x34/0x108 [ 36.950721] dwc3_gadget_giveback+0x50/0x68 [ 36.950723] dwc3_thread_interrupt+0x358/0x1488 [ 36.950731] irq_thread_fn+0x30/0x88 [ 36.950734] irq_thread+0x114/0x1b0 [ 36.950739] kthread+0x104/0x130 [ 36.950747] ret_from_fork+0x10/0x1c I isolated this down to in ffs_epfile_io(): https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/usb/gadget/function/f_fs.c#n1065 Where the completion done is setup on the stack: DECLARE_COMPLETION_ONSTACK(done); Then later we setup a request and queue it, and wait for it: if (unlikely(wait_for_completion_interruptible(&done))) { /* * To avoid race condition with ffs_epfile_io_complete, * dequeue the request first then check * status. usb_ep_dequeue API should guarantee no race * condition with req->complete callback. */ usb_ep_dequeue(ep->ep, req); interrupted = ep->status < 0; } The problem is, that we end up being interrupted, dequeue the request, and exit. But then the irq triggers and we try calling complete() on the context pointer which points to now random stack space, which results in the panic. Alan Stern pointed out there is a bug here, in that the snippet above "assumes that usb_ep_dequeue() waits until the request has been completed." And that: wait_for_completion(&done); Is needed right after the usb_ep_dequeue(). Thus this patch implements that change. With it I no longer see the crashes on suspend or reboot. This issue seems to have been uncovered by behavioral changes in the dwc3 driver in commit fec9095bdef4e ("usb: dwc3: gadget: remove wait_end_transfer"). Cc: Alan Stern Cc: Felipe Balbi Cc: Zeng Tao Cc: Jack Pham Cc: Thinh Nguyen Cc: Chen Yu Cc: Jerry Zhang Cc: Lars-Peter Clausen Cc: Vincent Pelletier Cc: Andrzej Pietrasiewicz Cc: Greg Kroah-Hartman Cc: Linux USB List Suggested-by: Alan Stern Signed-off-by: John Stultz Signed-off-by: Felipe Balbi

usb: gadget: f_fs: preserve wMaxPacketSize across usb_ep_autoconfig() call

2019-02-07T11:14:51Z

usb_ep_autoconfig() treats the passed descriptor as if it were an fs descriptor. In particular, for bulk endpoints, it clips wMaxPacketSize to 64. This patch preserves the original value. Signed-off-by: Andrzej Pietrasiewicz Signed-off-by: Felipe Balbi

usb: gadget: f_fs: Allow scatter-gather buffers

2018-11-26T07:06:32Z

Some protocols implemented in userspace with FunctionFS might require large buffers, e.g. 64kB or more. Currently the said memory is allocated with kmalloc, which might fail should system memory be highly fragmented. On the other hand, some UDC hardware allows scatter-gather operation and this patch takes advantage of this capability: if the requested buffer is larger than PAGE_SIZE and the UDC allows scatter-gather operation, then the buffer is allocated with vmalloc and a scatterlist describing it is created and passed to usb request. Signed-off-by: Andrzej Pietrasiewicz Signed-off-by: Felipe Balbi

usb: gadget: f_fs: Add support for CCID descriptors.

2018-11-26T07:06:32Z

Nothing to remap, only check length. Define a minimal structure for CCID descriptor only used to check length. As this descriptor shares the same value as HID descriptors, keep track and compare current interface's class to expected HID and CCID standard values. Signed-off-by: Vincent Pelletier Signed-off-by: Felipe Balbi

Revert "usb: gadget: ffs: Fix BUG when userland exits with submitted AIO transfers"

2018-11-14T09:15:13Z

This reverts commit b4194da3f9087dd38d91b40f9bec42d59ce589a8 since it causes list corruption followed by kernel panic: Workqueue: adb ffs_aio_cancel_worker RIP: 0010:__list_add_valid+0x4d/0x70 Call Trace: insert_work+0x47/0xb0 __queue_work+0xf6/0x400 queue_work_on+0x65/0x70 dwc3_gadget_giveback+0x44/0x50 [dwc3] dwc3_gadget_ep_dequeue+0x83/0x2d0 [dwc3] ? finish_wait+0x80/0x80 usb_ep_dequeue+0x1e/0x90 process_one_work+0x18c/0x3b0 worker_thread+0x3c/0x390 ? process_one_work+0x3b0/0x3b0 kthread+0x11e/0x140 ? kthread_create_worker_on_cpu+0x70/0x70 ret_from_fork+0x3a/0x50 This issue is seen with warm reboot stability testing. Signed-off-by: Shen Jing Signed-off-by: Saranya Gopal Signed-off-by: Felipe Balbi

usb: gadget: f_fs: Only return delayed status when len is 0

2018-07-20T14:02:49Z

Commit 1b9ba000 ("Allow function drivers to pause control transfers") states that USB_GADGET_DELAYED_STATUS is only supported if data phase is 0 bytes. It seems that when the length is not 0 bytes, there is no need to explicitly delay the data stage since the transfer is not completed until the user responds. However, when the length is 0, there is no data stage and the transfer is finished once setup() returns, hence there is a need to explicitly delay completion. This manifests as the following bugs: Prior to 946ef68ad4e4 ('Let setup() return USB_GADGET_DELAYED_STATUS'), when setup is 0 bytes, ffs would require user to queue a 0 byte request in order to clear setup state. However, that 0 byte request was actually not needed and would hang and cause errors in other setup requests. After the above commit, 0 byte setups work since the gadget now accepts empty queues to ep0 to clear the delay, but all other setups hang. Fixes: 946ef68ad4e4 ("Let setup() return USB_GADGET_DELAYED_STATUS") Signed-off-by: Jerry Zhang Cc: stable Acked-by: Felipe Balbi Signed-off-by: Greg Kroah-Hartman

usb: gadget: ffs: Fix BUG when userland exits with submitted AIO transfers

2018-06-18T09:40:59Z

This bug happens only when the UDC needs to sleep during usb_ep_dequeue, as is the case for (at least) dwc3. [ 382.200896] BUG: scheduling while atomic: screen/1808/0x00000100 [ 382.207124] 4 locks held by screen/1808: [ 382.211266] #0: (rcu_callback){....}, at: [] rcu_process_callbacks+0x260/0x440 [ 382.219949] #1: (rcu_read_lock_sched){....}, at: [] percpu_ref_switch_to_atomic_rcu+0xb0/0x130 [ 382.230034] #2: (&(&ctx->ctx_lock)->rlock){....}, at: [] free_ioctx_users+0x23/0xd0 [ 382.230096] #3: (&(&ffs->eps_lock)->rlock){....}, at: [] ffs_aio_cancel+0x20/0x60 [usb_f_fs] [ 382.230160] Modules linked in: usb_f_fs libcomposite configfs bnep btsdio bluetooth ecdh_generic brcmfmac brcmutil intel_powerclamp coretemp dwc3 kvm_intel ulpi udc_core kvm irqbypass crc32_pclmul crc32c_intel pcbc dwc3_pci aesni_intel aes_i586 crypto_simd cryptd ehci_pci ehci_hcd gpio_keys usbcore basincove_gpadc industrialio usb_common [ 382.230407] CPU: 1 PID: 1808 Comm: screen Not tainted 4.14.0-edison+ #117 [ 382.230416] Hardware name: Intel Corporation Merrifield/BODEGA BAY, BIOS 542 2015.01.21:18.19.48 [ 382.230425] Call Trace: [ 382.230438] [ 382.230466] dump_stack+0x47/0x62 [ 382.230498] __schedule_bug+0x61/0x80 [ 382.230522] __schedule+0x43/0x7a0 [ 382.230587] schedule+0x5f/0x70 [ 382.230625] dwc3_gadget_ep_dequeue+0x14c/0x270 [dwc3] [ 382.230669] ? do_wait_intr_irq+0x70/0x70 [ 382.230724] usb_ep_dequeue+0x19/0x90 [udc_core] [ 382.230770] ffs_aio_cancel+0x37/0x60 [usb_f_fs] [ 382.230798] kiocb_cancel+0x31/0x40 [ 382.230822] free_ioctx_users+0x4d/0xd0 [ 382.230858] percpu_ref_switch_to_atomic_rcu+0x10a/0x130 [ 382.230881] ? percpu_ref_exit+0x40/0x40 [ 382.230904] rcu_process_callbacks+0x2b3/0x440 [ 382.230965] __do_softirq+0xf8/0x26b [ 382.231011] ? __softirqentry_text_start+0x8/0x8 [ 382.231033] do_softirq_own_stack+0x22/0x30 [ 382.231042] [ 382.231071] irq_exit+0x45/0xc0 [ 382.231089] smp_apic_timer_interrupt+0x13c/0x150 [ 382.231118] apic_timer_interrupt+0x35/0x3c [ 382.231132] EIP: __copy_user_ll+0xe2/0xf0 [ 382.231142] EFLAGS: 00210293 CPU: 1 [ 382.231154] EAX: bfd4508c EBX: 00000004 ECX: 00000003 EDX: f3d8fe50 [ 382.231165] ESI: f3d8fe51 EDI: bfd4508d EBP: f3d8fe14 ESP: f3d8fe08 [ 382.231176] DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068 [ 382.231265] core_sys_select+0x25f/0x320 [ 382.231346] ? __wake_up_common_lock+0x62/0x80 [ 382.231399] ? tty_ldisc_deref+0x13/0x20 [ 382.231438] ? ldsem_up_read+0x1b/0x40 [ 382.231459] ? tty_ldisc_deref+0x13/0x20 [ 382.231479] ? tty_write+0x29f/0x2e0 [ 382.231514] ? n_tty_ioctl+0xe0/0xe0 [ 382.231541] ? tty_write_unlock+0x30/0x30 [ 382.231566] ? __vfs_write+0x22/0x110 [ 382.231604] ? security_file_permission+0x2f/0xd0 [ 382.231635] ? rw_verify_area+0xac/0x120 [ 382.231677] ? vfs_write+0x103/0x180 [ 382.231711] SyS_select+0x87/0xc0 [ 382.231739] ? SyS_write+0x42/0x90 [ 382.231781] do_fast_syscall_32+0xd6/0x1a0 [ 382.231836] entry_SYSENTER_32+0x47/0x71 [ 382.231848] EIP: 0xb7f75b05 [ 382.231857] EFLAGS: 00000246 CPU: 1 [ 382.231868] EAX: ffffffda EBX: 00000400 ECX: bfd4508c EDX: bfd4510c [ 382.231878] ESI: 00000000 EDI: 00000000 EBP: 00000000 ESP: bfd45020 [ 382.231889] DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 007b [ 382.232281] softirq: huh, entered softirq 9 RCU c10b4d90 with preempt_count 00000100, exited with 00000000? Tested-by: Sam Protsenko Signed-off-by: Vincent Pelletier Signed-off-by: Felipe Balbi