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path: root/drivers/usb/gadget/function
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11 hoursMerge branch 'for-next' of ↵Mark Brown
https://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi.git
10 daysMerge 7.3-rc6 into usb-nextGreg Kroah-Hartman
We need the usb/thunderbolt fixes in here to work off of. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
14 daysusb: gadget: f_uac1_legacy: validate bRequest index in generic_{set,get}_cmdLiu Chao
generic_set_cmd() and generic_get_cmd() use the low nibble of ctrl->bRequest as an index into con->data[]: u8 cmd = (ctrl->bRequest & 0x0F); /* 0 .. 15 */ ... con->data[cmd] = value; /* OOB when cmd >= 5 */ struct usb_audio_control (include/linux/usb/audio.h) declares data as a 5-element array, so indices 5 through 15 write (or read) up to 44 bytes past the end of the array on the heap. A malicious USB host can craft a class-specific SET_CUR / GET_CUR request with an arbitrary bRequest value, triggering the out-of-bounds access from an IRQ completion handler with no further preconditions. Add an ARRAY_SIZE() guard to both functions. Fixes: c47d7b09891a ("USB: audio: add USB audio class definitions") Cc: stable <stable@kernel.org> Reviewed-by: Weibin Liu <liuwb@xiaopeng.com> Signed-off-by: Liu Chao <liuc63@xiaopeng.com> Reviewed-by: Ivy Lopez <skunkolee@gmail.com> Link: https://patch.msgid.link/20260921072551.3708191-1-liuc63@xiaopeng.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
14 daysusb: gadget: f_fs: Fix NULL pointer dereference in FUNCTIONFS_ENDPOINT_DESCYuchao Zhang
When user space sets up FunctionFS with only full-speed descriptors (e.g., flags = FUNCTIONFS_HAS_FS_DESC) and the gadget operates at a higher speed (such as USB_SPEED_HIGH or USB_SPEED_SUPER), config_ep_by_speed() detects that the function lacks descriptors for the current speed, logs a warning, and falls back to full-speed descriptors. The endpoint is then successfully enabled via usb_ep_enable(), and epfile->ep becomes valid. However, when user space subsequently issues the FUNCTIONFS_ENDPOINT_DESC ioctl to query the endpoint descriptor, ffs_epfile_ioctl() selects the descriptor index solely based on gadget->speed: switch (epfile->ffs->gadget->speed) { case USB_SPEED_SUPER: case USB_SPEED_SUPER_PLUS: desc_idx = 2; break; case USB_SPEED_HIGH: desc_idx = 1; break; default: desc_idx = 0; } desc = epfile->ep->descs[desc_idx]; memcpy(&desc1, desc, desc->bLength); Because user space only supplied full-speed descriptors, epfile->ep->descs[1] is NULL. Dereferencing desc->bLength triggers an immediate kernel NULL pointer dereference panic. Fix this by falling back through lower speed descriptors if the current speed descriptor was not supplied, matching the fallback logic in config_ep_by_speed() and historical f_fs behavior. If still missing, fall back to epfile->ep->ep->desc (the active descriptor), and return -EINVAL safely if no valid descriptor is found. In addition, mark desc as const to match struct usb_ep::desc and avoid discarding qualifiers. Fixes: c559a3534109 ("usb: gadget: f_fs: add ioctl returning ep descriptor") Cc: stable@kernel.org Signed-off-by: Yuchao Zhang <ndaugoing@gmail.com> Acked-by: Michał Nazarewicz <mina86@mina86.com> Link: https://patch.msgid.link/20260918005438.81263-2-ndaugoing@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-09-22Merge tag 'v7.3-rc2' into 7.4/scsi-stagingMartin K. Petersen (Oracle)
Merge Linux 7.3-rc2 to resolve libata and mpi3mr merge conflicts. Signed-off-by: Martin K. Petersen (Oracle) <mkp@kernel.org> Conflicts: drivers/ata/libata-scsi.c drivers/scsi/mpi3mr/mpi3mr_transport.c
2026-09-16scsi: usb: storage: Use combined sense codesDamien Le Moal
Refactor the USB mass storage driver to replace all hard-coded additional sense codes and additional sense code qualifiers with the enum values defined in include/scsi/scsi_sense.h. This helps with code clarity as the sense codes being processed are easier to test and self-documented. No functional change intended. Signed-off-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Hannes Reinecke <hare@kernel.org> Link: https://patch.msgid.link/20260908090308.1085097-36-dlemoal@kernel.org Signed-off-by: Martin K. Petersen (Oracle) <mkp@kernel.org>
2026-09-10usb: gadget: f_mass_storage: ignore class requests while inactiveKeisuke Tsukuda
SET_CONFIGURATION is handled asynchronously by the mass-storage thread. A class request can arrive after the composite core selects the function but before the thread installs common->fsg, or while the function is being disabled. fsg_setup() already rejects this state with -EOPNOTSUPP, but checking it through fsg_is_set() also emits a warning. Check the active function directly so normal requests during a configuration transition are rejected without hiding fsg_is_set() warnings from other internal paths. Fixes: 8876f5e7d3b2 ("USB: gadget: f_mass_storage: added eject callback") Reported-by: syzbot+d31109047baed8f3b590@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=d31109047baed8f3b590 Signed-off-by: Keisuke Tsukuda <tkdkei@outlook.jp> Acked-by: Alan Stern <stern@rowland.harvard.edu> Link: https://patch.msgid.link/20260908203348.95825-3-tkdkei@outlook.jp Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-09-10usb: gadget: midi2: Fix the jack descriptor array sizesTakashi Iwai
The jack in/out descriptor arrays in struct f_midi2_usb_config have the size of MAX_CABLES, which look reasonable -- but it turned out to be incorrect. Namely, the entries for those arrays are added from both inputs and outputs, hence for each loop cycle, it adds two, ended up with as twice as the expected size. This inconsistency may result in potential OOB when a large number of jacks are set up via configfs, although the max number of cables (the loop count) is limited to MAX_CABLES. For addressing it, correct the jack_ins & jack_outs array sizes to twice, MAX_CABLES * 2. Fixes: 856fa444b098 ("usb: gadget: midi2: Dynamically create MIDI 1.0 altset descriptors") Cc: stable <stable@kernel.org> Reported-by: syzbot+c35f34092a4bc9855be6@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=c35f34092a4bc9855be6 Link: https://lore.kernel.org/20260826134606.127250-1-eadavis@sina.com Cc: Edward Adam Davis <eadavis@sina.com> Signed-off-by: Takashi Iwai <tiwai@suse.de> Link: https://patch.msgid.link/20260901145512.785142-1-tiwai@suse.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-09-06Merge tag 'usb-7.3-rc2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb Pull USB fixes from Greg KH: "Here are some small USB driver fixes for reported problems and regressions. Include in here are: - xhci driver fixes - cdns3 driver fixes - usb gadget driver fixes for syzbot found problems - typec driver fixes for broken hardware and other bugs found - kernel data leaks in mdc800 driver - usb storage driver fixes - other small USB driver fixes All of these have been in linux-next this week with no reported issues" * tag 'usb-7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (25 commits) usb: typec: qcom-pmic-typec: drain cc_debounce_dwork if port_start() fails usb: typec: qcom-pmic-typec: disable cc_debounce_dwork on stop usb: gadget: fix null pointer dereference in usb_put_function_instance() usb: typec: qcom-pmic: cancel reset_work on stop usb: gadget: f_mass_storage: fix null pointer dereference in fsg_common_set_num_buffers() usb: f_mass_storage: Bump local buffer size in fsg_common_create_luns() usb: storage: realtek_cr: fix use-after-free on disconnect usb: cdnsp: fix wakeup from S3 after controller context loss usb-storage: ene_ub6250: fix race between scan work and probe USB: gadget: fix NULL pointer dereference in gadget_dev_ioctl() usb: gadget: f_midi: initialize work in f_midi_alloc() usb: gadget: f_midi2: fix use-after-free in string attribute show path usb: typec: tipd: Fix Thunderbolt altmode VDOs for cd321x usb: gadget: midi2: Fix null-pointer dereference in f_midi2_free_ep_reqs usb: typec: hd3ss3220: track VBUS enable state per consumer usb: dwc3: clear forceRM when issuing EndTransfer usb: dwc3: google: Initialise probe properties with DWC3_DEFAULT_PROPERTIES usb: typec: mux: avoid duplicated mux switches usb: typec: mux: Fix typec_switch_match() usb: image: mdc800: change kmalloc() to kzalloc() ...
2026-09-04treewide: refresh kmalloc_obj() conversionsKees Cook
This is another run of the Coccinelle script for converting kmalloc() family of allocations to kmalloc_obj() via the existing rules in scripts/coccinelle/api/kmalloc_objs.cocci This catches both the set of kmalloc() uses added since the first kmalloc_obj() conversions in v7.0 and adds a large group missed in the first pass due to Coccinelle not interacting well with the cleanup.h scoped_...() family of macros[1]. I worked around this with spatch's "--macro-file" argument to a file with all the scoped_...() macros mapped to Coccinelle's YACFE_ITERATOR[2] as that was the closest viable control flow indicator I could find. Build tested allmodconfig on x86, arm64, arm, loongarch, mips, powerpc, riscv, and s390 with no new warnings. Link: https://lore.kernel.org/lkml/202609021314.8A9C0B8@keescook/ [1] Link: https://github.com/coccinelle/coccinelle/blob/master/standard.h [2] Signed-off-by: Kees Cook <kees+treewide@kernel.org>
2026-09-01usb: gadget: f_mass_storage: fix null pointer dereference in ↵Jeffin Philip
fsg_common_set_num_buffers() Previously fsg_num_buffers_validate() was removed as it was not necessary due to Kconfig setting the limits for n from 2 to 256 with default as 2. However, setting the page content in such a way that kstrtou8() reflects n value as either 0 or 1 bypasses these restrictions leading to a null pointer dereference if n is 0. Fix this by adding a check for n < 2 and returning -EINVAL if n is either 0 or 1 consistent with Kconfig logic. Reported-by: syzbot+791be35f1fbcc85d06d7@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=791be35f1fbcc85d06d7 Fixes: fe5a6c48fd95 ("usb: gadget: storage: get rid of fsg_num_buffers_validate()") Cc: stable <stable@kernel.org> Signed-off-by: Jeffin Philip <jeffinphilip14@gmail.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Link: https://patch.msgid.link/20260818035904.10324-1-jeffinphilip14@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-09-01usb: f_mass_storage: Bump local buffer size in fsg_common_create_luns()Andy Shevchenko
GCC (Debian 14.2.0-19) is not happy about the buffer size: drivers/usb/gadget/function/f_mass_storage.c:2970:48: error: ‘%d’ directive output may be truncated writing between 1 and 9 bytes into a region of size 5 [-Werror=format-truncation=] Bump the size to get it enough for all possible values. Note, although cfg->nluns is limited to FSG_MAX_LUNS (16), the compiler doesn't realize this and complains about the buffer size. Also note, the existing comment is wrong as size 8 for the whole buffer doesn't cover 100 mil numbers, hence drop it altogether. Fixes: b27c08c953e9 ("usb: gadget: f_mass_storage: create lun creation helpers for use in fsg_common_init") Cc: stable <stable@kernel.org> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://patch.msgid.link/20260817161239.1448582-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-09-01usb: gadget: f_midi: initialize work in f_midi_alloc()Jeffin Philip
f_midi_alloc initializes free_ref to 1 and it can only be incremented when a sound card is registered via f_midi_register_card(). f_midi_register_card() is only called in f_midi_bind() which actually performs INIT_WORK. If f_midi_bind() is never run, work is not initialized and the if condition in f_midi_free becomes true, this results in a warning later in __flush_work as work->func = 0. Fix this by moving INIT_WORK from f_midi_bind() to f_midi_alloc(). Reported-by: syzbot+d5fa3d224505c8610702@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=d5fa3d224505c8610702 Fixes: 8653d71ce376 ("usb/gadget: f_midi: Replace tasklet with work") Cc: stable <stable@kernel.org> Signed-off-by: Jeffin Philip <jeffinphilip14@gmail.com> Reviewed-by: Takashi Iwai <tiwai@suse.de> Link: https://patch.msgid.link/20260815054006.102325-1-jeffinphilip14@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-09-01usb: gadget: f_midi2: fix use-after-free in string attribute show pathIvy Lopez
f_midi2_opts_str_show() takes the string lock internally, but its callers dereference the opts->info.<field> pointer before calling it, outside the lock. This races with f_midi2_opts_str_store(), which frees the old string under opts->lock when the attribute is written concurrently, the show path can read a pointer that gets freed before the lock inside str_show() is even taken. Change f_midi2_opts_str_show() to take a pointer to the string field, matching the existing pattern in f_midi2_opts_str_store(), and dereference it only after the lock is held. Update all three callers (iface_name, block name, and the EP string option macro) accordingly. Reported-by: syzbot+2280f1cca5e6b0c353e4@syzkaller.appspotmail.com Cc: stable <stable@kernel.org> Closes: https://syzkaller.appspot.com/bug?extid=2280f1cca5e6b0c353e4 Signed-off-by: Ivy Lopez <skunkolee@gmail.com> Reviewed-by: Takashi Iwai <tiwai@suse.de> Link: https://patch.msgid.link/20260816005434.34018-1-skunkolee@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-09-01usb: gadget: midi2: Fix null-pointer dereference in f_midi2_free_ep_reqsAleksandr Nogikh
A null-pointer dereference occurs in f_midi2_free_ep_reqs() when attempting to clean up an endpoint that was never initialized. When configuring the MIDI 2.0 gadget via configfs and setting the block direction to SNDRV_UMP_DIR_INPUT, the initialization of the midi1_ep_out endpoint is explicitly skipped during the gadget bind phase (f_midi2_bind()). As a result, the usb_ep->card field remains NULL. Later, when the host sets the alternate setting, f_midi2_set_alt() unconditionally stops both the IN and OUT endpoints by calling f_midi2_stop_eps(), which in turn calls f_midi2_free_ep_reqs() for both endpoints. When f_midi2_free_ep_reqs() is called for the uninitialized midi1_ep_out, it attempts to dereference usb_ep->card to determine the number of requests to free, leading to a crash. Fix this by using usb_ep->num_reqs instead of usb_ep->card->info.num_reqs in f_midi2_free_ep_reqs(). usb_ep->num_reqs is correctly set during f_midi2_init_ep() and remains 0 if the endpoint was never initialized, safely avoiding the loop. For consistency, apply the same change to f_midi2_alloc_ep_reqs(). Oops: general protection fault, probably for non-canonical address 0xdffffc00000000ee: 0000 [#1] SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000770-0x0000000000000777] ... RIP: 0010:f_midi2_free_ep_reqs drivers/usb/gadget/function/f_midi2.c:1166 [inline] RIP: 0010:f_midi2_stop_eps+0x28e/0x4d0 drivers/usb/gadget/function/f_midi2.c:1246 ... Call Trace: <TASK> f_midi2_set_alt+0x11c/0xf00 drivers/usb/gadget/function/f_midi2.c:1296 composite_setup+0x1ffd/0x3480 drivers/usb/gadget/composite.c:1933 configfs_composite_setup+0xbd/0x100 drivers/usb/gadget/configfs.c:1877 Fixes: 8b645922b223 ("usb: gadget: Add support for USB MIDI 2.0 function driver") Cc: stable <stable@kernel.org> Assisted-by: Gemini:gemini-3.5-flash Gemini:gemini-3.1-pro-preview syzbot Reported-by: syzbot+bbb6dad313f4aaa8da6b@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=bbb6dad313f4aaa8da6b Link: https://syzkaller.appspot.com/ai_job?id=8ce30b1a-8cf7-4e38-bcf7-1f69e6f6313f Signed-off-by: Aleksandr Nogikh <nogikh@google.com> Reviewed-by: Takashi Iwai <tiwai@suse.de> Closes: https://syzkaller.appspot.com/bug?extid=01a17afb30637396955e Link: https://patch.msgid.link/cafe65f4-e1bb-46a3-901d-732814b861b2@mail.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-08-14usb: gadget: uvc: fix dangling pointers in uvc_function_bind() and ↵Jeffin Philip
uvc_function_unbind() In uvc_function_bind() error path, we use usb_ep_free_request which uses uvc->control_req but does not set it to NULL afterwards. Thus, uvc->control_req is a dangling pointer causing a UAF. Also we do not set the uvc->control_buf pointer to NULL after freeing it, which is another dangling pointer. Fix it by setting uvc->control_req to NULL after we run usb_ep_free_request() and uvc->control_buf to NULL after kfree. Do the same for uvc_function_unbind(). Reported-by: syzbot+de553c19cb054f174a35@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=de553c19cb054f174a35 Fixes: 0f9df9393855 ("usb: gadget: uvc: fix error path in uvc_function_bind()") Fixes: 6d11ed76c45d ("usb: gadget: f_uvc: convert f_uvc to new function interface") Cc: stable@vger.kernel.org Signed-off-by: Jeffin Philip <jeffinphilip14@gmail.com> Link: https://patch.msgid.link/20260813174311.130823-1-jeffinphilip14@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-08-14usb: gadget: u_audio: Fix use-after-free on sound card disconnectSonali Pradhan
g_audio_cleanup() invokes snd_card_free_when_closed() to initiate sound card teardown and immediately frees the underlying struct snd_uac_chip context. However, snd_card_free_when_closed() returns asynchronously while ALSA control elements (kctls) remain open in userspace. When userspace control applications access or close these open file descriptors, kctl callbacks attempt to dereference kctl->private_data pointing to &uac->c_prm or &uac->p_prm within the freed uac structure, resulting in a use-after-free (UAF) memory corruption. Fix this issue by deferring the destruction of struct snd_uac_chip until all references to the ALSA sound card are released. Register a custom card->private_free callback (u_audio_card_free) during g_audio_setup() that frees uac and its associated playback/capture request and ring buffers only when the sound card reference count drops to zero. Fixes: 6c67ed9ad9b8 ("usb: gadget: u_audio: don't let userspace block driver unbind") Cc: stable@vger.kernel.org Signed-off-by: Sonali Pradhan <sonalipradhan@google.com> Link: https://patch.msgid.link/20260810071237.2207680-1-sonalipradhan@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-08-14usb: gadget: f_tcm: keep port count until LUN teardown completesShuangpeng Bai
tcm_usbg_drop_nexus() permits session removal once tpg_port_count reaches zero. However, usbg_port_unlink() currently decrements that count from the fabric_pre_unlink() callback, before core_dev_del_lun() waits for active se_lun references to drain. If removal of the last LUN races a nexus removal, the latter can observe a zero port count and call target_remove_session(). This frees sess_cmd_map while an in-flight struct usbg_cmd, including its work item, can still be accessed. Overlapping the last-LUN unlink with nexus removal reproduces this lifetime violation as a DEBUG_OBJECTS "free active" warning for usbg_cmd_work, followed by a target-core BUG/Oops. The generic target-core unlink path has no callback after core_dev_del_lun() completes. Add an optional fabric_post_unlink() callback and use it for the f_tcm port count. The count now remains nonzero until core_dev_del_lun() has finished draining active LUN references, preventing nexus removal from freeing the session during command completion. Fixes: c52661d60f63 ("usb-gadget: Initial merge of target module for UASP + BOT") Cc: stable@vger.kernel.org Signed-off-by: Shuangpeng Bai <shuangpeng.kernel@gmail.com> Link: https://patch.msgid.link/20260807060733.3186624-1-shuangpeng.kernel@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-08-14usb: gadget: f_tcm: fix deadlock in usbg_make_tpg()Yun Zhou
usbg_make_tpg() held dep_lock while calling configfs_depend_item_unlocked(), which acquires the configfs root inode lock when operating across subsystems. This creates a circular lock dependency with configfs_rmdir(): dep_lock -> configfs root inode lock -> su_mutex -> dep_lock In usbg_make_tpg(), dep_lock only serialized the read of opts->ready, which is a monotonic flag that transitions from false to true exactly once (in tcm_set_name()) and never reverts. Remove dep_lock from usbg_make_tpg() entirely and use READ_ONCE/WRITE_ONCE to access opts->ready locklessly instead. Reported-by: syzbot+c9f9d646b08f3b6032fe@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=c9f9d646b08f3b6032fe Fixes: 4bb8548df632 ("usb: gadget: f_tcm: add configfs support") Cc: stable@vger.kernel.org Signed-off-by: Yun Zhou <yun.zhou@windriver.com> Link: https://patch.msgid.link/20260731081151.285599-1-yun.zhou@windriver.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-08-14usb: gadget: f_fs: Fix Use-After-Free in AIO error pathNeill Kapron
In ffs_epfile_write_iter() and ffs_epfile_read_iter(), when ffs_epfile_io() fails with an error other than -EIOCBQUEUED, the io_data structure (`p`) is freed. However, for AIO operations, the kiocb cancel function was already armed and kiocb->private was set to `p`. If a concurrent cancel operation (such as sys_io_cancel()) executes after ffs_epfile_io() fails but before the function frees `p`, a Use-After-Free can occur when the cancellation handler accesses the freed pointer. To securely fix this race condition, we must properly un-arm the cancellation. Invoking `kiocb->ki_complete()` does exactly this by acquiring `ctx->ctx_lock` and safely removing the kiocb from the active sequence. In doing so, it ensures that a parallel io_cancel can no longer discover the kiocb, effectively closing the race window. We then return -EIOCBQUEUED to notify the VFS layer that the kiocb has been consumed and it should avoid attempting to complete the request again or triggering subsequent completion handlers. Fixes: de2080d41b5d ("gadget/function/f_fs.c: close leaks") Cc: stable@vger.kernel.org Reported-by: Xingyu Jin <xingyuj@google.com> Assisted-by: Antigravity:gemini-3.1-pro Signed-off-by: Neill Kapron <nkapron@google.com> Link: https://patch.msgid.link/20260724235100.106011-1-nkapron@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-08-14usb: gadget: f_fs: Prevent deadlock during ep0 read loopNeill Kapron
Currently, ffs_ep0_read() holds ffs->mutex when it prepares to go to sleep waiting for an event. When no setup events are pending, it calls wait_event_interruptible_exclusive_locked_irq() with the mutex still held. The wait macro deliberately drops the waitqueue spinlock before sleeping but does not drop the mutex. If a userspace daemon is polling ep0 via read() and the gadget is asynchronously torn down via configfs (e.g., echo "" > UDC), a deadlock can occur: 1. The configfs teardown calls functionfs_unbind(), which queues a FUNCTIONFS_UNBIND event. 2. The daemon wakes up, consumes the event, and drops the mutex. 3. However, if the daemon loops and immediately issues another read() before exiting, it reacquires ffs->mutex and again goes into an interruptible sleep. 4. Meanwhile, functionfs_unbind() continues execution and attempts to acquire ffs->mutex to tear down ep0req. 5. The kernel deadlocks because the configfs thread is stuck in an uninterruptible sleep waiting for the mutex, while the userspace daemon is in an interruptible sleep holding the mutex forever because no more events will arrive. To fix this, we drop both the waitqueue spinlock and ffs->mutex before going to sleep, and use wait_event_interruptible_exclusive() instead. Upon waking up, we jump back to the `retry` label to safely reacquire the mutex and re-evaluate the state machine. By not sleeping with ffs->mutex held, we natively decouple gadget teardowns (which require the mutex) from userspace polling. Fixes: ddf8abd25994 ("USB: f_fs: the FunctionFS driver") Cc: stable@vger.kernel.org Assisted-by: Antigravity:gemini-3.1-pro Signed-off-by: Neill Kapron <nkapron@google.com> Link: https://patch.msgid.link/20260724204117.4036015-1-nkapron@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-08-14usb: gadget: midi2: remove default configfs groups on teardownJoshua Crofts
f_midi2_alloc_inst() creates default configfs child groups for the default endpoint and default block using configfs_add_default_group(), setting their internal refcount to 1. However, during function teardown in f_midi2_free_inst() or EP cleanup in f_midi2_ep_opts_release(), configfs_remove_default_groups() is never called, therefore never dropping the refcount and leaking struct f_midi2_ep_opts and f_midi2_block_opts. Add the missing configfs_remove_default_groups() in the afformentioned functions to free the structs properly. Fixes: 8b645922b223 ("usb: gadget: Add support for USB MIDI 2.0 function driver") Cc: stable@vger.kernel.org Reported-by: syzbot+eaa106d192c9daf37f95@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=eaa106d192c9daf37f95 Tested-by: syzbot+eaa106d192c9daf37f95@syzkaller.appspotmail.com Signed-off-by: Joshua Crofts <joshua.crofts1@gmail.com> Link: https://patch.msgid.link/20260730135811.1498-1-joshua.crofts1@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-08-14usb: gadget: uvc: Fix null pointer dereference in uvcg_video_init()Jeffin Philip
In uvcg_video_init(), if kthread_run_worker() fails, the error logged uses uvcg_err(), however, the pointer it uses: video->uvc is not assigned at this point, triggering a null pointer dereference. Fix this by directly using uvc->func which is assigned already. Reported-by: syzbot+8dcac923582c28505fd7@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=8dcac923582c28505fd7 Fixes: f0bbfbd16b3b ("usb: gadget: uvc: rework to enqueue in pump worker from encoded queue") Cc: stable@vger.kernel.org Signed-off-by: Jeffin Philip <jeffinphilip14@gmail.com> Reviewed-by: Xu Yang <xu.yang_2@nxp.com> Link: https://patch.msgid.link/20260804034338.7976-1-jeffinphilip14@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-08-14Merge 7.2-rc7 into usb-nextGreg Kroah-Hartman
We need the USB fixes in here as well to build on top of. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-08-03usb: gadget: f_ncm: Use unsigned int for ndp_indexSonali Pradhan
The variable ndp_index is declared as a signed integer, but it stores the return value of get_ncm(), which is unsigned. A malicious host can supply a large offset that overflows the signed ndp_index, making it negative. Because ndp_index is compared against unsigned bounds, this negative value bypasses sanity checks and leads to an out-of-bounds read when calculating the address of the NDP block (ntb_ptr + ndp_index). Fix this by changing ndp_index to unsigned int to ensure consistent unsigned comparisons throughout the function. Fixes: 370af734dfaf ("usb: gadget: NCM: RX function support multiple NDPs") Cc: stable <stable@kernel.org> Signed-off-by: Sonali Pradhan <sonalipradhan@google.com> Link: https://patch.msgid.link/20260720165654.2224591-1-sonalipradhan@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-07-27Merge 7.2-rc5 into usb-nextGreg Kroah-Hartman
We need the USB fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-07-23usb: gadget: f_mass_storage: Remove obsolete version logFabio Estevam
The mass-storage function prints the following message whenever a function instance is allocated: Mass Storage Function, version: 2009/09/11 The hard-coded date does not identify the running kernel or provide useful diagnostic information. Remove the message and the unused version definition. Signed-off-by: Fabio Estevam <festevam@gmail.com> Link: https://patch.msgid.link/20260721020957.81956-1-festevam@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-07-17usb: gadget: f_uac1_legacy: remove broken string configfs attributesXu Yang
The UAC1_STR_ATTRIBUTE macro defines configfs show/store handlers for the fn_play, fn_cap, and fn_cntl string options. The store function contains an inverted null check on the kstrndup() return value. This means every write attempt returns -ENOMEM on success and dereferences a NULL pointer on allocation failure. The attributes have been broken and unused for many years. Remove the UAC1_STR_ATTRIBUTE macro and the three attributes it generated. The internal defaults (FILE_PCM_PLAYBACK, FILE_PCM_CAPTURE, FILE_CONTROL) set in f_audio_alloc_inst() are unaffected. Fixes: 0854611a19ae ("usb: gadget: f_uac1: add configfs support") Link: https://lore.kernel.org/linux-usb/20260625113154.1954813-1-xu.yang_2@oss.nxp.com/ Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Assisted-by: Claude:claude-sonnet-4.6 Signed-off-by: Xu Yang <xu.yang_2@nxp.com> Reviewed-by: Frank Li <Frank.Li@nxp.com> Link: https://patch.msgid.link/20260713060845.3759673-1-xu.yang_2@oss.nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-07-17usb: gadget: f_fs: fix __le16 of wMaxPacketSizeBen Dooks
The wMaxPacketSize is __le16 type, fix the sparse warnings by changing the type. Fixes the following sparse warnings: drivers/usb/gadget/function/f_fs.c:3346:32: warning: incorrect type in assignment (different base types) drivers/usb/gadget/function/f_fs.c:3346:32: expected unsigned short [usertype] wMaxPacketSize drivers/usb/gadget/function/f_fs.c:3346:32: got restricted __le16 [usertype] wMaxPacketSize drivers/usb/gadget/function/f_fs.c:3371:36: warning: incorrect type in assignment (different base types) drivers/usb/gadget/function/f_fs.c:3371:36: expected restricted __le16 [usertype] wMaxPacketSize drivers/usb/gadget/function/f_fs.c:3371:36: got unsigned short [usertype] wMaxPacketSize Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk> Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@collabora.com> Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com> Link: https://patch.msgid.link/20260713122822.1331334-1-ben.dooks@codethink.co.uk Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-07-13usb: gadget: printer: fix infinite loop in printer_read()Melbin K Mathew
printer_read() uses the same variable for the requested copy size and the number of bytes actually copied to user space. copy_to_user() returns the number of bytes not copied, so when it fails to copy anything, the computed copied length becomes zero. In that case len, buf, current_rx_bytes and current_rx_buf are left unchanged. If RX data is available and the user buffer remains unwritable, the read loop can repeat indefinitely. Track the copied length separately and return -EFAULT, or the number of bytes already copied, if an iteration makes no progress. Fixes: b185f01a9ab7 ("usb: gadget: printer: factor out f_printer") Cc: stable <stable@kernel.org> Reviewed-by: Peter Chen <peter.chen@kernel.org> Signed-off-by: Melbin K Mathew <mlbnkm1@gmail.com> Link: https://patch.msgid.link/20260709205622.55700-1-mlbnkm1@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-07-13usb: gadget: f_midi: cancel pending IN work before freeing the midi objectFan Wu
The f_midi driver embeds a work item (midi->work) whose handler, f_midi_in_work(), dereferences the enclosing struct f_midi through container_of(). This work is armed from two sites: f_midi_complete(), on a normal IN-endpoint completion, and f_midi_in_trigger(), on an ALSA rawmidi output-stream start. Neither f_midi_disable() nor f_midi_unbind() cancels midi->work. f_midi_disable() only disables the endpoints and drains the in_req_fifo; it does not synchronize the work item, and the sound card is released asynchronously to the final free of the midi object. The midi object is reference-counted (midi->free_ref) and is freed in f_midi_free() only once both the usb_function reference and the rawmidi private_data reference have been dropped. In f_midi_unbind(), f_midi_disable() runs before the sound card is released, so while the USB endpoints are already disabled the rawmidi device is still usable by an open substream. A concurrent userspace write on such a substream can reach f_midi_in_trigger() and queue midi->work again after f_midi_disable() has returned. A work item armed this way may still be pending when the last reference drops and f_midi_free() proceeds to kfree(midi), letting f_midi_in_work() dereference the struct after it has been freed, a use-after-free. For this reason cancelling midi->work in f_midi_disable() would not be sufficient: the ALSA trigger path can rearm the work after disable() returns. Cancelling at the refcount-zero free site is the boundary after which neither arming source can survive, because by then both references that keep the midi object alive have been dropped: the USB endpoints are already disabled and the rawmidi device has been released. Fix this by calling cancel_work_sync(&midi->work) in the refcount-zero block of f_midi_free(), before the embedded work_struct is freed along with the rest of the structure. opts->lock is a sleeping mutex, so calling cancel_work_sync() under it is permitted, and the handler takes midi->transmit_lock rather than opts->lock, so no self-deadlock can occur while it waits for a running instance of the work to finish. This issue was found by an in-house static analysis tool. Fixes: 8653d71ce3763 ("usb/gadget: f_midi: Replace tasklet with work") Cc: stable <stable@kernel.org> Assisted-by: Codex:gpt-5.5 Signed-off-by: Fan Wu <fanwu01@zju.edu.cn> Link: https://patch.msgid.link/20260709150717.399083-1-fanwu01@zju.edu.cn Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-07-13usb: gadget: f_ncm: validate datagram bounds in ncm_unwrap_ntb()Sonali Pradhan
When unpacking host-supplied NTBs, ncm_unwrap_ntb() checks datagram length against frame_max but does not verify that the datagram fits within the declared block length. Additionally, when decoding multiple NTBs from a single socket buffer, subsequent block lengths are not checked against the actual remaining buffer data. With these checks missing, a malicious USB host can specify datagram offsets and lengths that point beyond the block, or supply secondary NTB headers declaring lengths larger than the buffer. skb_put_data() then copies adjacent kernel memory from skb_shared_info into the network skb. Fix this by verifying that sufficient buffer space remains for the NTB header before parsing, handling zero-length block declarations, ensuring that block lengths never exceed the remaining buffer space, and verifying that each datagram payload stays strictly within the block boundary. Fixes: 427694cfaafa ("usb: gadget: ncm: Handle decoding of multiple NTB's in unwrap call") Fixes: 2b74b0a04d3e ("USB: gadget: f_ncm: add bounds checks to ncm_unwrap_ntb()") Cc: stable <stable@kernel.org> Assisted-by: Jetski:Gemini-2.5-Pro Signed-off-by: Sonali Pradhan <sonalipradhan@google.com> Link: https://patch.msgid.link/20260703083725.1903850-1-sonalipradhan@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-07-13usb: gadget: uvc: clamp SEND_RESPONSE length to the response bufferMuhammad Bilal
uvc_send_response() builds the UVC control response from a user-supplied struct uvc_request_data: req->length = min_t(unsigned int, uvc->event_length, data->length); ... memcpy(req->buf, data->data, req->length); req->length is clamped to uvc->event_length, which is taken from the host control request wLength (up to UVC_MAX_REQUEST_SIZE, 64), and to data->length, which comes from the UVCIOC_SEND_RESPONSE ioctl and is only checked for being negative. The source buffer data->data is only 60 bytes, so a response with uvc->event_length and data->length both greater than 60 makes memcpy() read past the end of data->data. Clamp req->length to sizeof(data->data) as well. Fixes: a5eaaa1f33e7 ("usb: gadget: uvc: use capped length value") Cc: stable <stable@kernel.org> Signed-off-by: Muhammad Bilal <meatuni001@gmail.com> Link: https://patch.msgid.link/20260629195004.148405-1-meatuni001@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-07-13usb: gadget: f_tcm: synchronize delayed set_alt with teardownCen Zhang
The f_tcm set_alt() path defers endpoint setup to a work item and completes the delayed status response from process context. The delayed work uses f_tcm private state and may complete the setup request after disconnect or function teardown has already moved on. Cancel and drain the delayed set_alt work when the function is unbound or freed. For disable paths, which are reached under the composite device lock, use a small state machine and a non-sleeping cancellation path instead of cancel_work_sync(). If the work is already running, mark it cancelled and let the worker own the cleanup; otherwise tcm_disable() can cancel the queued work and clean up immediately. Also serialize the final delayed-status completion with the cancellation check while holding the composite device lock. This prevents a disconnect from clearing delayed_status while the worker is about to complete the control request. Validation reproduced this kernel report: BUG: KASAN: slab-use-after-free in tcm_delayed_set_alt+0x6c/0xef0 Call Trace: <TASK> dump_stack_lvl+0x66/0xa0 print_report+0xce/0x630 ? tcm_delayed_set_alt+0x6c/0xef0 ? srso_alias_return_thunk+0x5/0xfbef5 ? __virt_addr_valid+0x188/0x320 ? tcm_delayed_set_alt+0x6c/0xef0 kasan_report+0xe0/0x110 ? tcm_delayed_set_alt+0x6c/0xef0 tcm_delayed_set_alt+0x6c/0xef0 ? __pfx_tcm_delayed_set_alt+0x10/0x10 ? process_one_work+0x4cb/0xb90 ? rcu_is_watching+0x20/0x50 ? tcm_delayed_set_alt+0x9/0xef0 process_one_work+0x4d7/0xb90 ? __pfx_process_one_work+0x10/0x10 ? srso_alias_return_thunk+0x5/0xfbef5 ? __list_add_valid_or_report+0x37/0xf0 ? __pfx_tcm_delayed_set_alt+0x10/0x10 ? srso_alias_return_thunk+0x5/0xfbef5 worker_thread+0x2d8/0x570 ? __pfx_worker_thread+0x10/0x10 kthread+0x1ad/0x1f0 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x3c9/0x540 ? __pfx_ret_from_fork+0x10/0x10 ? srso_alias_return_thunk+0x5/0xfbef5 ? __switch_to+0x2e9/0x730 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 </TASK> Allocated by task 544: kasan_save_stack+0x33/0x60 kasan_save_track+0x14/0x30 __kasan_kmalloc+0x8f/0xa0 tcm_alloc+0x68/0x180 usb_get_function+0x36/0x60 config_usb_cfg_link+0x125/0x1b0 configfs_symlink+0x322/0x890 vfs_symlink+0xc2/0x270 filename_symlinkat+0x295/0x2f0 __x64_sys_symlinkat+0x62/0x90 do_syscall_64+0x115/0x6a0 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 661: kasan_save_stack+0x33/0x60 kasan_save_track+0x14/0x30 kasan_save_free_info+0x3b/0x60 __kasan_slab_free+0x43/0x70 kfree+0x2f9/0x530 config_usb_cfg_unlink+0x173/0x1e0 configfs_unlink+0x1fa/0x340 vfs_unlink+0x15c/0x510 filename_unlinkat+0x2ba/0x450 __x64_sys_unlinkat+0x63/0x90 do_syscall_64+0x115/0x6a0 entry_SYSCALL_64_after_hwframe+0x77/0x7f Fixes: c52661d60f63 ("usb-gadget: Initial merge of target module for UASP + BOT") Cc: stable <stable@kernel.org> Assisted-by: Codex:gpt-5.5 Signed-off-by: Cen Zhang <zzzccc427@gmail.com> Link: https://patch.msgid.link/20260627104153.3822495-1-zzzccc427@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-07-13Merge 7.2-rc3 into usb-nextGreg Kroah-Hartman
We need the USB fixes in here as well to build on top of. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-07-10USB: gadget: ffs: fix mm lifetime handlingGabriel Prostitis
io_data stores a pointer to the submitting task's mm_struct, but does not currently hold a reference to it while async requests are pending. This can result in a use-after-free if the task exits before completion handling finishes. Take a reference with mmgrab() when queuing the read request and release it with mmdrop() on request completion. Reported-by: Gabriel Prostitis <prostitisgabriel@gmail.com> Signed-off-by: Gabriel Prostitis <prostitisgabriel@gmail.com> Link: https://patch.msgid.link/20260601-mm-uaf-fix-v2-1-3c942a707bce@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-07-10usb: gadget: u_audio: clean up capture endpoint on feedback failureXu Rao
u_audio_start_capture() enables the capture OUT endpoint, queues capture requests and marks the stream active before setting up the optional feedback endpoint. If feedback endpoint configuration or enablement fails, the function returns an error while the capture endpoint remains enabled and its requests may remain queued. The current code even leaves TODO comments at these return paths. Unwind the already started capture endpoint on these failures. Also set fb_ep_enabled only after usb_ep_enable() succeeds, so the software state matches the endpoint state. Signed-off-by: Xu Rao <raoxu@uniontech.com> Link: https://patch.msgid.link/183621D513E0DE8B+20260611091229.4017443-1-raoxu@uniontech.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-07-10usb: gadget: f_fs: Introduce rw_proxy file descriptorsNeill Kapron
Currently, FunctionFS exposes each USB endpoint as a separate, unidirectional file descriptor (e.g., `ep1` for IN, `ep2` for OUT). While this mirrors the underlying hardware structure, it forces userspace daemons implementing bidirectional protocols to manage multiple file descriptors. When dealing with legacy protocols which require exposing a single, bi-directional fd to userspace, this becomes problematic. This patch introduces the `FUNCTIONFS_RW_PROXY_EPS` UAPI flag. When passed in the descriptor header during initialization, FunctionFS provisions a "rw_proxy" bidirectional file descriptor (e.g., `ep1_rw`) alongside every pair of IN/OUT endpoints. Implementation details: - RW proxy files act as a pure VFS alias, proxying operations directly to the base ffs_epfile instances. A `read()` proxies to the OUT endpoint's file, and a `write()` proxies to the IN file. - Because operations are proxied natively, they reuse the underlying base endpoint's lock (`epfile->mutex`) and tracking state. This serializes concurrent I/O, preventing buffer corruption or races even if userspace mixes transfers across both the rw_proxy and base files while allowing full-duplex synchronous operations to occur concurrently without serializing on a single lock. - Control operations (like IOCTLs) and intentional stalls (via reverse-direction I/O) must still be issued on the base endpoints, as the rw_proxy returns `-ENOTTY` for IOCTLs and cannot trigger stalls. Assisted-by: Antigravity:gemini-3.1-pro Signed-off-by: Neill Kapron <nkapron@google.com> Link: https://patch.msgid.link/20260619040609.4010746-5-nkapron@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-07-10usb: gadget: f_fs: Add zero-length packet ioctlNeill Kapron
When transferring data from a USB gadget to a host, a transfer is considered complete when the host receives a short packet (a packet smaller than wMaxPacketSize). If the total transfer length is an exact multiple of wMaxPacketSize, a Zero-Length Packet (ZLP) must be appended to signal the end of the transfer. FunctionFS currently provides no mechanism for userspace to instruct the kernel to set the `req->zero` flag on transfers. Userspace workarounds, such as manually submitting separate 0-byte requests, may not be available for legacy protocols which must maintain write behavior compatibility when moved to functionfs implementations. To resolve this, introduce a new ioctl, FUNCTIONFS_ENDPOINT_ENABLE_ZLP, which takes a pointer to a __u32 flag. When enabled, all subsequent transfers on that endpoint will have the `req->zero` flag set, allowing the underlying USB Device Controller (UDC) hardware to automatically append a ZLP only when mathematically required. For logical transfers chunked across multiple requests, userspace can dynamically toggle this flag, enabling it only prior to submitting the final chunk. The flag defaults to false to maintain backward compatibility. Once enabled, the state is persistent for the lifetime of the endpoint and will not be reset by opening or closing the endpoint file descriptors. Assisted-by: Gemini-CLI:gemini-3.1-pro-preview Signed-off-by: Neill Kapron <nkapron@google.com> Link: https://patch.msgid.link/20260619040609.4010746-4-nkapron@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-07-10usb: gadget: f_fs: Fix fence cleanup in ffs_dmabuf_transfer() error pathsNuno Sá
The error paths for endpoint-disabled (ESHUTDOWN) and request-allocation failure (ENOMEM) in ffs_dmabuf_transfer() jump to err_fence_put which calls dma_fence_put() on the fence. However, at that point the fence has only been kmalloc'd — dma_fence_init() has not been called yet, so the refcount and the fence ops are uninitialized. Calling dma_fence_put() on such an object leads to undefined behavior. Use kfree() instead, since the fence is just a plain allocation at this stage, and rename the label to err_fence_free to reflect the actual cleanup action. Fixes: 7b07a2a7ca02 ("usb: gadget: functionfs: Add DMABUF import interface") Signed-off-by: Nuno Sá <nuno.sa@analog.com> Reviewed-by: Paul Cercueil <paul@crapouillou.net> Link: https://patch.msgid.link/20260612-fix-f_fs-fence-cleanup-v1-1-79f489b0efe9@analog.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-07-10usb: gadget: uac: validate rate list length before storingQing Ming
UAC1 and UAC2 configfs rate-list attributes parse a comma-separated list of sampling rates and store each parsed value in fixed-size arrays. The arrays have UAC_MAX_RATES entries, but the store paths do not check that the input contains at most that many tokens before writing through opts->name##s[i++]. Writing more than ten rates therefore writes past the end of the p_srates[] or c_srates[] array in struct f_uac1_opts or struct f_uac2_opts. With CONFIG_UBSAN_BOUNDS enabled, writing an 11-entry rate list to the UAC1 p_srate attribute reports: UBSAN: array-index-out-of-bounds drivers/usb/gadget/function/f_uac1.c:1669:1 index 10 is out of range for type 'int [10]' __ubsan_handle_out_of_bounds.cold f_uac1_opts_p_srate_store configfs_write_iter vfs_write ksys_write do_syscall_64 The same reproducer against the UAC2 p_srate attribute reports: UBSAN: array-index-out-of-bounds drivers/usb/gadget/function/f_uac2.c:2087:1 index 10 is out of range for type 'int [10]' __ubsan_handle_out_of_bounds.cold f_uac2_opts_p_srate_store configfs_write_iter vfs_write ksys_write do_syscall_64 Reject additional tokens once UAC_MAX_RATES entries have been parsed. Also keep the original kstrdup() pointer for kfree(), because strsep() advances the parsing cursor. Freeing the advanced cursor leaks the original buffer on successful parses and can free an interior pointer on some error paths. Fixes: 695d39ffc2b5 ("usb: gadget: f_uac1: Support multiple sampling rates") Fixes: a7339e4f5788 ("usb: gadget: f_uac2: Support multiple sampling rates") Signed-off-by: Qing Ming <a0yami@mailbox.org> Link: https://patch.msgid.link/20260519143319.147494-1-a0yami@mailbox.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-07-08usb: gadget: function: rndis: add length check for headerGriffin Kroah-Hartman
Add a length check for the rndis header in rndis_rm_hdr, to ensure that MessageType, MessageLength, DataOffset, and DataLength fields are present before they are accessed. Assisted-by: gkh_clanker_2000 Cc: stable <stable@kernel.org> Signed-off-by: Griffin Kroah-Hartman <griffin@kroah.com> Link: https://patch.msgid.link/20260708-usb-gadget-rndis-v1-2-e77e026dcc6a@kroah.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-07-08usb: gadget: function: rndis: add length check to response queryGriffin Kroah-Hartman
Add variable representations for BufLength and BufOffset in rndis_query_response(), and perform a length check on them. This is identical to how rndis_set_response() handles these parameters. Assisted-by: gkh_clanker_2000 Cc: stable <stable@kernel.org> Signed-off-by: Griffin Kroah-Hartman <griffin@kroah.com> Link: https://patch.msgid.link/20260708-usb-gadget-rndis-v1-1-e77e026dcc6a@kroah.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-07-08usb: gadget: f_printer: take kref only for successful openXu Rao
printer_open() returns -EBUSY when the character device is already open, but it increments dev->kref regardless of the return value. VFS does not call ->release() for a failed open, so every rejected second open permanently leaks one reference. Move kref_get() into the successful-open branch. Fixes: e8d5f92b8d30 ("usb: gadget: function: printer: fix use-after-free in __lock_acquire") Cc: stable <stable@kernel.org> Signed-off-by: Xu Rao <raoxu@uniontech.com> Link: https://patch.msgid.link/80295742B820DA9B+20260626064617.4090626-1-raoxu@uniontech.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-06-25usb: gadget: f_fs: Tie read_buffer lifetime to ffs_epfileNeill Kapron
Currently, ffs_epfile_release unconditionally frees the endpoint's read_buffer when a file descriptor is closed. If userspace explicitly opens the endpoint multiple times and closes one, the read_buffer is destroyed. This can lead to silent data loss if other file descriptors are still actively reading from the endpoint. By tying the lifetime of the read_buffer to the ffs_epfile structure itself (which is destroyed when the functionfs instance is torn down in ffs_epfiles_destroy), we eliminate the brittle dependency on open/release calls while correctly matching the conceptual lifetime of unread data on the hardware endpoint. Fixes: 9353afbbfa7b ("usb: gadget: f_fs: buffer data from ‘oversized’ OUT requests") Cc: stable <stable@kernel.org> Assisted-by: Antigravity:gemini-3.1-pro Signed-off-by: Neill Kapron <nkapron@google.com> Link: https://patch.msgid.link/20260619040609.4010746-3-nkapron@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-06-25usb: gadget: f_fs: Initialize epfile->in early to fix endpoint direction checksNeill Kapron
When parsing endpoint descriptors, ffs_data_got_descs() generates the eps_addrmap which contains the endpoint direction. However, epfile->in was previously only populated in ffs_func_eps_enable() which executes upon USB host connection. As a result, early userspace ioctls like FUNCTIONFS_DMABUF_ATTACH that run before the host connects would see epfile->in as 0, leading to incorrect DMA directions. By moving the initialization to ffs_epfiles_create(), epfile->in is accurate before userspace opens the endpoint files. Fixes: 7b07a2a7ca02 ("usb: gadget: functionfs: Add DMABUF import interface") Cc: stable <stable@kernel.org> Assisted-by: Antigravity:gemini-3.1-pro Signed-off-by: Neill Kapron <nkapron@google.com> Link: https://patch.msgid.link/20260619040609.4010746-2-nkapron@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-06-25usb: gadget: f_fs: initialize reset_work at allocation timeTyler Baker
ffs_fs_kill_sb() unconditionally calls cancel_work_sync() on ffs->reset_work when a functionfs instance is unmounted: ffs_data_reset(ffs); cancel_work_sync(&ffs->reset_work); However ffs->reset_work is only ever initialized via INIT_WORK() in ffs_func_set_alt() and ffs_func_disable(), and only on the FFS_DEACTIVATED path. That state is reached solely by ffs_data_closed() when the instance is mounted with the "no_disconnect" option, so for the common case (no "no_disconnect", or mounted and unmounted without ever being deactivated) reset_work is never initialized. ffs_data_new() allocates the ffs_data with kzalloc_obj() and does not initialize reset_work, and ffs_data_reset()/ffs_data_clear() do not touch it either, so reset_work.func is left NULL. cancel_work_sync() on such a work then trips the WARN_ON(!work->func) guard in __flush_work(): WARNING: kernel/workqueue.c:4301 at __flush_work+0x330/0x360, CPU#3: umount Call trace: __flush_work cancel_work_sync ffs_fs_kill_sb [usb_f_fs] deactivate_locked_super deactivate_super cleanup_mnt __cleanup_mnt task_work_run exit_to_user_mode_loop el0_svc On older kernels cancel_work_sync() on a zero-initialized work struct was a silent no-op, which hid the missing initialization. Initialize reset_work once in ffs_data_new() so it is always valid for the lifetime of the ffs_data, and drop the now-redundant INIT_WORK() calls from the two deactivation paths. Fixes: 18d6b32fca38 ("usb: gadget: f_fs: add "no_disconnect" mode") Cc: stable <stable@kernel.org> Signed-off-by: Tyler Baker <tyler.baker@oss.qualcomm.com> Cc: Loic Poulain <loic.poulain@oss.qualcomm.com> Cc: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com> Cc: Srinivas Kandagatla <srinivas.kandagatla@oss.qualcomm.com> Tested-by: Loic Poulain <loic.poulain@oss.qualcomm.com> Reviewed-by: Peter Chen <peter.chen@kernel.org> Acked-by: Michał Nazarewicz <mina86@mina86.com> Link: https://patch.msgid.link/20260609193635.2284430-1-tyler.baker@oss.qualcomm.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-06-25usb: gadget: f_fs: Fix DMA fence leakPaul Cercueil
In ffs_dmabuf_transfer(), a ffs_dma_fence object is kmalloc'd, with the underlying dma_fence later initialized by dma_fence_init(), which sets its kref counter to 1. Then, dma_resv_add_fence() gets a second reference, and a pointer to the ffs_dma_fence is passed as the usb_request's "context" field. The dma-resv mechanism will manage the second reference, but the first reference is never properly released; the ffs_dmabuf_cleanup() function decreases the reference count, but only to balance with the reference grab in ffs_dmabuf_signal_done(). The code will then slowly leak memory as more ffs_dma_fence objects are created without being ever freed. Address this issue by transferring ownership of the fence to the DMA reservation object, by calling dma_fence_put() right after dma_resv_add_fence(). The ffs_dma_fence then gets properly discarded after being signalled. Fixes: 7b07a2a7ca02 ("usb: gadget: functionfs: Add DMABUF import interface") Cc: stable <stable@kernel.org> Signed-off-by: Paul Cercueil <paul@crapouillou.net> Tested-by: Nuno Sá <nuno.sa@analog.com> Reviewed-by: Nuno Sá <nuno.sa@analog.com> Link: https://patch.msgid.link/20260609152905.729328-1-paul@crapouillou.net Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-05-22usb: gadget: f_fs: serialize DMABUF cancel against request completionMichael Bommarito
ffs_epfile_dmabuf_io_complete() calls usb_ep_free_request() on the completed request but leaves priv->req, the back-pointer that ffs_dmabuf_transfer() set on submission, pointing at the freed memory. A later FUNCTIONFS_DMABUF_DETACH ioctl or ffs_epfile_release() on the close path still sees priv->req non-NULL under ffs->eps_lock: if (priv->ep && priv->req) usb_ep_dequeue(priv->ep, priv->req); so usb_ep_dequeue() is called on a freed usb_request. On dummy_hcd the dequeue path only walks a live queue and pointer-compares, so the freed pointer reads without faulting and KASAN requires an explicit check at the FunctionFS call site to surface the use-after-free. On SG-capable in-tree UDCs the dequeue path dereferences the supplied request immediately: * chipidea's ep_dequeue() does container_of(req, struct ci_hw_req, req) and reads hwreq->req.status before acquiring its own lock. * cdnsp's cdnsp_gadget_ep_dequeue() reads request->status first. The narrower option of clearing priv->req via cmpxchg() in the completion does not close the race: the completion runs without eps_lock, so a cancel path holding eps_lock can still observe priv->req non-NULL, race a concurrent completion that clears and frees, and pass the freed pointer to usb_ep_dequeue(). A slightly longer fix that moves the free into the cleanup work is needed. Same class of lifetime race as the recent usbip-vudc timer fix [1]. Take eps_lock in the sole place that mutates priv->req from the callback direction by moving usb_ep_free_request() out of the completion into ffs_dmabuf_cleanup(), the existing work handler scheduled by ffs_dmabuf_signal_done() on ffs->io_completion_wq. Clear priv->req there under eps_lock before freeing, and only clear if priv->req still names our request (a subsequent ffs_dmabuf_transfer() on the same attachment may have queued a new one). This keeps the existing dummy_hcd sync-dequeue invariant: the completion callback is still invoked by the UDC without eps_lock held (dummy_hcd drops its own lock before calling the callback), and the callback now takes no f_fs lock at all. Serialization against the cancel path happens in cleanup, which runs from the workqueue with no f_fs lock held on entry. The priv ref count protects the containing ffs_dmabuf_priv: ffs_dmabuf_transfer() takes a ref via ffs_dmabuf_get(), cleanup drops it via ffs_dmabuf_put(), so priv stays live for the cleanup even after the cancel path's list_del + ffs_dmabuf_put. The ffs_dmabuf_transfer() error path no longer frees usb_req inline: fence->req and fence->ep are set before usb_ep_queue(), so ffs_dmabuf_cleanup() (scheduled by the error-path ffs_dmabuf_signal_done()) owns the free regardless of whether the queue succeeded. Reproduced under KASAN on both detach and close paths against dummy_hcd with an observability hook (kasan_check_byte(priv->req) immediately before usb_ep_dequeue) at the two FunctionFS cancel sites to surface the stale-pointer access; the hook is not part of this patch. The KASAN allocator / free stacks in the captured splats identify the same request: alloc in dummy_alloc_request, free in dummy_timer, fault reached from ffs_epfile_release (close) and from the FUNCTIONFS_DMABUF_DETACH ioctl (detach). With the patch applied, both paths are silent under the same hook. The bug is reached from the FunctionFS device node, which in real deployments is owned by the privileged gadget daemon (adbd, UMS, composite gadget services, etc.); it is not reachable from unprivileged userspace or from a USB host on the cable. FunctionFS mounts default to GLOBAL_ROOT_UID, but the filesystem supports uid=, gid=, and fmode= delegation to a non-root gadget daemon, so on real deployments the attacker may be a less-privileged service rather than root. Fixes: 7b07a2a7ca02 ("usb: gadget: functionfs: Add DMABUF import interface") Link: https://lore.kernel.org/all/20260417163552.807548-1-michael.bommarito@gmail.com/ [1] Cc: stable <stable@kernel.org> Assisted-by: Claude:claude-opus-4-7 Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com> Link: https://patch.msgid.link/20260419161227.1587668-1-michael.bommarito@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-05-22usb: gadget: f_fs: copy only received bytes on short ep0 readMichael Bommarito
ffs_ep0_read() allocates its control-OUT data buffer with kmalloc() (not kzalloc) at the Length value from the Setup packet, then copies that full len to userspace regardless of how many bytes were actually received: data = kmalloc(len, GFP_KERNEL); ... ret = __ffs_ep0_queue_wait(ffs, data, len); if ((ret > 0) && (copy_to_user(buf, data, len))) ret = -EFAULT; __ffs_ep0_queue_wait() returns req->actual, which on a short control OUT transfer is strictly less than len. The copy_to_user() call still copies len bytes, so on a short OUT the last (len - ret) bytes of the kmalloc() buffer -- uninitialised slab residue -- are delivered to the FunctionFS daemon. Short ep0 OUT completions are specified USB control-transfer behavior and are produced by in-tree UDCs: * dwc2 continues on req->actual < req->length for ep0 DATA OUT (short-not-ok is the only ep0-OUT stall path). * aspeed_udc ends ep0 OUT on rx_len < ep->ep.maxpacket. * renesas_usbf logs "ep0 short packet" and completes the request. * dwc3 stalls on short IN but not on short OUT. A short ep0 OUT is therefore not evidence of a broken UDC; it is a normal condition f_fs has to cope with. The sibling gadgetfs implementation in drivers/usb/gadget/legacy/inode.c already does this correctly via min(len, dev->req->actual) before copy_to_user(). This patch brings f_fs.c to the same safe pattern rather than trimming at a defensive layer. The bug is reached from the FunctionFS device node, which in real deployments is owned by the privileged gadget daemon (adbd, UMS, composite gadget services, etc.); it is not reachable from unprivileged userspace. Linux host stacks normally reject short-wLength control OUTs before they reach the gadget, so reproducing this required a build that bypasses that host-side check. With the bypass in place, a 1-byte payload on a 64-byte Setup produces 63 bytes of non-canary slab residue in the daemon's read buffer. Fix by copying only ret (actually received) bytes to userspace. Fixes: ddf8abd25994 ("USB: f_fs: the FunctionFS driver") Cc: stable <stable@kernel.org> Assisted-by: Claude:claude-opus-4-7 Signed-off-by: Michael Bommarito <michael.bommarito@gmail.com> Link: https://patch.msgid.link/20260419160359.1577270-1-michael.bommarito@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>