kernel/linux.git/drivers/hid/hid-core.c, branch v6.12.81

HID: core: Harden s32ton() against conversion to 0 bits

2025-09-09T16:58:04+00:00

[ Upstream commit a6b87bfc2ab5bccb7ad953693c85d9062aef3fdd ] Testing by the syzbot fuzzer showed that the HID core gets a shift-out-of-bounds exception when it tries to convert a 32-bit quantity to a 0-bit quantity. Ideally this should never occur, but there are buggy devices and some might have a report field with size set to zero; we shouldn't reject the report or the device just because of that. Instead, harden the s32ton() routine so that it returns a reasonable result instead of crashing when it is called with the number of bits set to 0 -- the same as what snto32() does. Signed-off-by: Alan Stern Reported-by: syzbot+b63d677d63bcac06cf90@syzkaller.appspotmail.com Closes: https://lore.kernel.org/linux-usb/68753a08.050a0220.33d347.0008.GAE@google.com/ Tested-by: syzbot+b63d677d63bcac06cf90@syzkaller.appspotmail.com Fixes: dde5845a529f ("[PATCH] Generic HID layer - code split") Cc: stable@vger.kernel.org Link: https://patch.msgid.link/613a66cd-4309-4bce-a4f7-2905f9bce0c9@rowland.harvard.edu Signed-off-by: Benjamin Tissoires Signed-off-by: Sasha Levin

HID: stop exporting hid_snto32()

2025-09-09T16:58:04+00:00

[ Upstream commit c653ffc283404a6c1c0e65143a833180c7ff799b ] The only user of hid_snto32() is Logitech HID++ driver, which always calls hid_snto32() with valid size (constant, either 12 or 8) and therefore can simply use sign_extend32(). Make the switch and remove hid_snto32(). Move snto32() and s32ton() to avoid introducing forward declaration. Signed-off-by: Dmitry Torokhov Link: https://patch.msgid.link/20241003144656.3786064-2-dmitry.torokhov@gmail.com [bentiss: fix checkpatch warning] Signed-off-by: Benjamin Tissoires Stable-dep-of: a6b87bfc2ab5 ("HID: core: Harden s32ton() against conversion to 0 bits") Signed-off-by: Sasha Levin

HID: simplify snto32()

2025-09-09T16:58:04+00:00

[ Upstream commit ae9b956cb26c0fd5a365629f2d723ab2fb14df79 ] snto32() does exactly what sign_extend32() does, but handles potentially malformed data coming from the device. Keep the checks, but then call sign_extend32() to perform the actual conversion. Signed-off-by: Dmitry Torokhov Link: https://patch.msgid.link/20241003144656.3786064-1-dmitry.torokhov@gmail.com Signed-off-by: Benjamin Tissoires Stable-dep-of: a6b87bfc2ab5 ("HID: core: Harden s32ton() against conversion to 0 bits") Signed-off-by: Sasha Levin

HID: core: do not bypass hid_hw_raw_request

2025-07-24T06:56:22+00:00

commit c2ca42f190b6714d6c481dfd3d9b62ea091c946b upstream. hid_hw_raw_request() is actually useful to ensure the provided buffer and length are valid. Directly calling in the low level transport driver function bypassed those checks and allowed invalid paramto be used. Reported-by: Alan Stern Closes: https://lore.kernel.org/linux-input/c75433e0-9b47-4072-bbe8-b1d14ea97b13@rowland.harvard.edu/ Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20250710-report-size-null-v2-3-ccf922b7c4e5@kernel.org Signed-off-by: Benjamin Tissoires Signed-off-by: Greg Kroah-Hartman

HID: core: ensure __hid_request reserves the report ID as the first byte

2025-07-24T06:56:22+00:00

commit 0d0777ccaa2d46609d05b66ba0096802a2746193 upstream. The low level transport driver expects the first byte to be the report ID, even when the report ID is not use (in which case they just shift the buffer). However, __hid_request() whas not offsetting the buffer it used by one in this case, meaning that the raw_request() callback emitted by the transport driver would be stripped of the first byte. Note: this changes the API for uhid devices when a request is made through hid_hw_request. However, several considerations makes me think this is fine: - every request to a HID device made through hid_hw_request() would see that change, but every request made through hid_hw_raw_request() already has the new behaviour. So that means that the users are already facing situations where they might have or not the first byte being the null report ID when it is 0. We are making things more straightforward in the end. - uhid is mainly used for BLE devices - uhid is also used for testing, but I don't see that change a big issue - for BLE devices, we can check which kernel module is calling hid_hw_request() - and in those modules, we can check which are using a Bluetooth device - and then we can check if the command is used with a report ID or not. - surprise: none of the kernel module are using a report ID 0 - and finally, bluez, in its function set_report()[0], does the same shift if the report ID is 0 and the given buffer has a size > 0. [0] https://git.kernel.org/pub/scm/bluetooth/bluez.git/tree/profiles/input/hog-lib.c#n879 Reported-by: Alan Stern Closes: https://lore.kernel.org/linux-input/c75433e0-9b47-4072-bbe8-b1d14ea97b13@rowland.harvard.edu/ Reported-by: syzbot+8258d5439c49d4c35f43@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=8258d5439c49d4c35f43 Tested-by: syzbot+8258d5439c49d4c35f43@syzkaller.appspotmail.com Fixes: 4fa5a7f76cc7 ("HID: core: implement generic .request()") Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20250710-report-size-null-v2-2-ccf922b7c4e5@kernel.org Signed-off-by: Benjamin Tissoires Signed-off-by: Greg Kroah-Hartman

HID: core: ensure the allocated report buffer can contain the reserved report ID

2025-07-24T06:56:22+00:00

commit 4f15ee98304b96e164ff2340e1dfd6181c3f42aa upstream. When the report ID is not used, the low level transport drivers expect the first byte to be 0. However, currently the allocated buffer not account for that extra byte, meaning that instead of having 8 guaranteed bytes for implement to be working, we only have 7. Reported-by: Alan Stern Closes: https://lore.kernel.org/linux-input/c75433e0-9b47-4072-bbe8-b1d14ea97b13@rowland.harvard.edu/ Cc: stable@vger.kernel.org Suggested-by: Alan Stern Link: https://patch.msgid.link/20250710-report-size-null-v2-1-ccf922b7c4e5@kernel.org Signed-off-by: Benjamin Tissoires Signed-off-by: Greg Kroah-Hartman

HID: core: Fix assumption that Resolution Multipliers must be in Logical Collections

2025-02-08T08:56:55+00:00

commit 64f2657b579343cf923aa933f08074e6258eb07b upstream. A report in 2019 by the syzbot fuzzer was found to be connected to two errors in the HID core associated with Resolution Multipliers. One of the errors was fixed by commit ea427a222d8b ("HID: core: Fix deadloop in hid_apply_multiplier."), but the other has not been fixed. This error arises because hid_apply_multipler() assumes that every Resolution Multiplier control is contained in a Logical Collection, i.e., there's no way the routine can ever set multiplier_collection to NULL. This is in spite of the fact that the function starts with a big comment saying: * "The Resolution Multiplier control must be contained in the same * Logical Collection as the control(s) to which it is to be applied. ... * If no Logical Collection is * defined, the Resolution Multiplier is associated with all * controls in the report." * HID Usage Table, v1.12, Section 4.3.1, p30 * * Thus, search from the current collection upwards until we find a * logical collection... The comment and the code overlook the possibility that none of the collections found may be a Logical Collection. The fix is to set the multiplier_collection pointer to NULL if the collection found isn't a Logical Collection. Reported-by: syzbot+ec5f884c4a135aa0dbb9@syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/000000000000109c040597dc5843@google.com/ Signed-off-by: Alan Stern Cc: Peter Hutterer Fixes: 5a4abb36f312 ("HID: core: process the Resolution Multiplier") Cc: stable@vger.kernel.org Signed-off-by: Jiri Kosina Signed-off-by: Greg Kroah-Hartman

HID: add per device quirk to force bind to hid-generic

2024-12-14T19:03:39+00:00

[ Upstream commit 645c224ac5f6e0013931c342ea707b398d24d410 ] We already have the possibility to force not binding to hid-generic and rely on a dedicated driver, but we couldn't do the other way around. This is useful for BPF programs where we are fixing the report descriptor and the events, but want to avoid a specialized driver to come after BPF which would unwind everything that is done there. Reviewed-by: Peter Hutterer Link: https://patch.msgid.link/20241001-hid-bpf-hid-generic-v3-8-2ef1019468df@kernel.org Signed-off-by: Benjamin Tissoires Signed-off-by: Sasha Levin

Merge tag 'hid-for-linus-20241105' of git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid

2024-11-06T17:49:54+00:00

Pull HID fix from Jiri Kosina: - report buffer sanitization fix for HID core (Jiri Kosina) * tag 'hid-for-linus-20241105' of git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid: HID: core: zero-initialize the report buffer

HID: core: zero-initialize the report buffer

2024-10-29T14:44:42+00:00

Since the report buffer is used by all kinds of drivers in various ways, let's zero-initialize it during allocation to make sure that it can't be ever used to leak kernel memory via specially-crafted report. Fixes: 27ce405039bf ("HID: fix data access in implement()") Reported-by: Benoît Sevens Acked-by: Benjamin Tissoires Signed-off-by: Jiri Kosina