In the Linux kernel, the following vulnerability has been resolved:

Input: cs40l50-vibra - validate custom data from user space

cs40l50_add() copies the custom data of an FF_PERIODIC/FF_CUSTOM effect
straight from the ff_effect the user passed to EVIOCSFF, without
requiring it to hold anything:

work_data.custom_data = memdup_array_user(periodic->custom_data,
periodic->custom_len,
sizeof(s16));
work_data.custom_len = periodic->custom_len;

The driver then reads two words out of that buffer: custom_data[0] as the
waveform bank in cs40l50_effect_bank_set(), and custom_data[1] as the
index within the bank in cs40l50_effect_index_set(). Neither read is
covered by a length check, and custom_len is fully user controlled:

- custom_len == 0 makes memdup_array_user() call memdup_user() with a
length of zero, which returns ZERO_SIZE_PTR rather than an error, so
custom_data[0] dereferences it.

- custom_len == 1 allocates two bytes. A bank of ROM or RAM keeps
effect->type out of the OWT case, and custom_data[1] is then read one
word past the allocation.

The bank value itself is also mishandled. It is masked with
CS40L50_CUSTOM_DATA_MASK (0xffff) but stored in an s16, so a
custom_data[0] of 0x8000 or above wraps to a negative value that passes
the "bank_type >= CS40L50_WVFRM_BANK_NUM" test.
cs40l50_effect_index_set() indexes vib->dsp.banks[] with it before the
switch statement's default case gets a chance to reject it:

base_index = vib->dsp.banks[effect->type].base_index;
max_index = vib->dsp.banks[effect->type].max_index;

Require the two words the driver reads to be present, and hold the masked
bank in a u32 so the existing upper-bound test covers the whole range.
The da7280 haptic driver already range checks custom_len this way.

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History

Wed, 26 Aug 2026 16:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-125
CWE-476

Wed, 26 Aug 2026 14:45:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: Input: cs40l50-vibra - validate custom data from user space cs40l50_add() copies the custom data of an FF_PERIODIC/FF_CUSTOM effect straight from the ff_effect the user passed to EVIOCSFF, without requiring it to hold anything: work_data.custom_data = memdup_array_user(periodic->custom_data, periodic->custom_len, sizeof(s16)); work_data.custom_len = periodic->custom_len; The driver then reads two words out of that buffer: custom_data[0] as the waveform bank in cs40l50_effect_bank_set(), and custom_data[1] as the index within the bank in cs40l50_effect_index_set(). Neither read is covered by a length check, and custom_len is fully user controlled: - custom_len == 0 makes memdup_array_user() call memdup_user() with a length of zero, which returns ZERO_SIZE_PTR rather than an error, so custom_data[0] dereferences it. - custom_len == 1 allocates two bytes. A bank of ROM or RAM keeps effect->type out of the OWT case, and custom_data[1] is then read one word past the allocation. The bank value itself is also mishandled. It is masked with CS40L50_CUSTOM_DATA_MASK (0xffff) but stored in an s16, so a custom_data[0] of 0x8000 or above wraps to a negative value that passes the "bank_type >= CS40L50_WVFRM_BANK_NUM" test. cs40l50_effect_index_set() indexes vib->dsp.banks[] with it before the switch statement's default case gets a chance to reject it: base_index = vib->dsp.banks[effect->type].base_index; max_index = vib->dsp.banks[effect->type].max_index; Require the two words the driver reads to be present, and hold the masked bank in a u32 so the existing upper-bound test covers the whole range. The da7280 haptic driver already range checks custom_len this way.
Title Input: cs40l50-vibra - validate custom data from user space
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
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cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2026-08-26T14:37:34.942Z

Reserved: 2026-08-26T14:34:25.768Z

Link: CVE-2026-80575

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-08-26T15:17:13.530

Modified: 2026-08-26T15:17:13.530

Link: CVE-2026-80575

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-08-26T18:30:02Z

Weaknesses