{"id":"CVE-2026-80575","state":"PUBLISHED","title":"Input: cs40l50-vibra - validate custom data from user space","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nInput: cs40l50-vibra - validate custom data from user space\n\ncs40l50_add() copies the custom data of an FF_PERIODIC/FF_CUSTOM effect\nstraight from the ff_effect the user passed to EVIOCSFF, without\nrequiring it to hold anything:\n\n    work_data.custom_data = memdup_array_user(periodic->custom_data,\n                                              periodic->custom_len,\n                                              sizeof(s16));\n    work_data.custom_len = periodic->custom_len;\n\nThe driver then reads two words out of that buffer: custom_data[0] as the\nwaveform bank in cs40l50_effect_bank_set(), and custom_data[1] as the\nindex within the bank in cs40l50_effect_index_set().  Neither read is\ncovered by a length check, and custom_len is fully user controlled:\n\n  - custom_len == 0 makes memdup_array_user() call memdup_user() with a\n    length of zero, which returns ZERO_SIZE_PTR rather than an error, so\n    custom_data[0] dereferences it.\n\n  - custom_len == 1 allocates two bytes.  A bank of ROM or RAM keeps\n    effect->type out of the OWT case, and custom_data[1] is then read one\n    word past the allocation.\n\nThe bank value itself is also mishandled.  It is masked with\nCS40L50_CUSTOM_DATA_MASK (0xffff) but stored in an s16, so a\ncustom_data[0] of 0x8000 or above wraps to a negative value that passes\nthe \"bank_type >= CS40L50_WVFRM_BANK_NUM\" test.\ncs40l50_effect_index_set() indexes vib->dsp.banks[] with it before the\nswitch statement's default case gets a chance to reject it:\n\n    base_index = vib->dsp.banks[effect->type].base_index;\n    max_index = vib->dsp.banks[effect->type].max_index;\n\nRequire the two words the driver reads to be present, and hold the masked\nbank in a u32 so the existing upper-bound test covers the whole range.\nThe da7280 haptic driver already range checks custom_len this way.","publishedAt":"2026-08-26T14:37:34.942Z","updatedAt":"2026-08-27T05:01:57.416Z","severity":{"score":7.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"c38fe1bb5d21c2ce0857965ee06174ee587d6b42","status":"affected","lessThan":"3855b6a11f8a7aceb8181cc08c99afef58517006","versionType":"git"},{"version":"c38fe1bb5d21c2ce0857965ee06174ee587d6b42","status":"affected","lessThan":"52a818c586ae2c36b7324bfaefb547f5e866a8ae","versionType":"git"},{"version":"c38fe1bb5d21c2ce0857965ee06174ee587d6b42","status":"affected","lessThan":"d38554602a0b04e85fad28ce72c7500cf50d419b","versionType":"git"},{"version":"c38fe1bb5d21c2ce0857965ee06174ee587d6b42","status":"affected","lessThan":"7d5c576cb1c86047b1fcb1aa9532e17fc5e46c1d","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/input/misc/cs40l50-vibra.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.11","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.11","versionType":"semver"},{"version":"6.12.105","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.46","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.10","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/input/misc/cs40l50-vibra.c"]}],"references":["https://git.kernel.org/stable/c/3855b6a11f8a7aceb8181cc08c99afef58517006","https://git.kernel.org/stable/c/52a818c586ae2c36b7324bfaefb547f5e866a8ae","https://git.kernel.org/stable/c/d38554602a0b04e85fad28ce72c7500cf50d419b","https://git.kernel.org/stable/c/7d5c576cb1c86047b1fcb1aa9532e17fc5e46c1d"],"weaknesses":[],"ingestedAt":"2026-10-29T20:13:07.220Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/80xxx/CVE-2026-80575.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-80575","state":"PUBLISHED","datePublished":"2026-08-26T14:37:34.942Z","dateUpdated":"2026-08-27T05:01:57.416Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-08-26T14:34:25.768Z"},"containers":{"cna":{"title":"Input: cs40l50-vibra - validate custom data from user space","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nInput: cs40l50-vibra - validate custom data from user space\n\ncs40l50_add() copies the custom data of an FF_PERIODIC/FF_CUSTOM effect\nstraight from the ff_effect the user passed to EVIOCSFF, without\nrequiring it to hold anything:\n\n    work_data.custom_data = memdup_array_user(periodic->custom_data,\n                                              periodic->custom_len,\n                                              sizeof(s16));\n    work_data.custom_len = periodic->custom_len;\n\nThe driver then reads two words out of that buffer: custom_data[0] as the\nwaveform bank in cs40l50_effect_bank_set(), and custom_data[1] as the\nindex within the bank in cs40l50_effect_index_set().  Neither read is\ncovered by a length check, and custom_len is fully user controlled:\n\n  - custom_len == 0 makes memdup_array_user() call memdup_user() with a\n    length of zero, which returns ZERO_SIZE_PTR rather than an error, so\n    custom_data[0] dereferences it.\n\n  - custom_len == 1 allocates two bytes.  A bank of ROM or RAM keeps\n    effect->type out of the OWT case, and custom_data[1] is then read one\n    word past the allocation.\n\nThe bank value itself is also mishandled.  It is masked with\nCS40L50_CUSTOM_DATA_MASK (0xffff) but stored in an s16, so a\ncustom_data[0] of 0x8000 or above wraps to a negative value that passes\nthe \"bank_type >= CS40L50_WVFRM_BANK_NUM\" test.\ncs40l50_effect_index_set() indexes vib->dsp.banks[] with it before the\nswitch statement's default case gets a chance to reject it:\n\n    base_index = vib->dsp.banks[effect->type].base_index;\n    max_index = vib->dsp.banks[effect->type].max_index;\n\nRequire the two words the driver reads to be present, and hold the masked\nbank in a u32 so the existing upper-bound test covers the whole range.\nThe da7280 haptic driver already range checks custom_len this way."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"c38fe1bb5d21c2ce0857965ee06174ee587d6b42","status":"affected","lessThan":"3855b6a11f8a7aceb8181cc08c99afef58517006","versionType":"git"},{"version":"c38fe1bb5d21c2ce0857965ee06174ee587d6b42","status":"affected","lessThan":"52a818c586ae2c36b7324bfaefb547f5e866a8ae","versionType":"git"},{"version":"c38fe1bb5d21c2ce0857965ee06174ee587d6b42","status":"affected","lessThan":"d38554602a0b04e85fad28ce72c7500cf50d419b","versionType":"git"},{"version":"c38fe1bb5d21c2ce0857965ee06174ee587d6b42","status":"affected","lessThan":"7d5c576cb1c86047b1fcb1aa9532e17fc5e46c1d","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/input/misc/cs40l50-vibra.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.11","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.11","versionType":"semver"},{"version":"6.12.105","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.46","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.10","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/input/misc/cs40l50-vibra.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/3855b6a11f8a7aceb8181cc08c99afef58517006"},{"url":"https://git.kernel.org/stable/c/52a818c586ae2c36b7324bfaefb547f5e866a8ae"},{"url":"https://git.kernel.org/stable/c/d38554602a0b04e85fad28ce72c7500cf50d419b"},{"url":"https://git.kernel.org/stable/c/7d5c576cb1c86047b1fcb1aa9532e17fc5e46c1d"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - Exploitation requires a local EVIOCSFF ioctl on the cs40l50_vibra evdev node (/dev/input/event*), traversing evdev_do_ioctl(), input_ff_upload(), and cs40l50_add(); there is no network, adjacent-radio, or physical-insertion path to this driver.\nAC:L - The attacker fully controls ff_effect fields (custom_len, custom_data[0]/[1], waveform type) passed through EVIOCSFF, so custom_len==0, custom_len==1, or bank values >=0x8000 deterministically trigger the missing checks without races or uncontrollable layout.\nPR:L - No capability check exists on the EVIOCSFF path beyond opening the input device; on Android phones, Chromebooks, kiosks, and desktops, logged-in users or session uaccess ACLs commonly grant local access to haptic/input event nodes without init-namespace root.\nUI:N - Once the attacker can open the cs40l50_vibra event device, they issue EVIOCSFF themselves with crafted FF_PERIODIC/FF_CUSTOM parameters; no separate victim mount, plug-in, or interactive action is required.\nS:U - Impact is confined to kernel memory handling and haptic-driver state within the local host kernel; it does not cross VM, container, IOMMU, or other security-scope boundaries.\nC:H - custom_len==1 forces a kmalloc heap out-of-bounds read of custom_data[1], and s16 bank sign-wrap indexes dsp.banks[] out of bounds before validation, leaking adjacent kernel memory; custom_len==0 dereferences ZERO_SIZE_PTR on read.\nI:H - Unchecked custom_len and sign-wrapped bank values cause out-of-bounds kernel memory accesses in the force-feedback upload path; per CNA guidance such heap/array boundary violations in ioctl handlers are scored High because they can corrupt subsequent kernel arithmetic and device register programming.\nA:H - custom_len==0 makes memdup_array_user return ZERO_SIZE_PTR and cs40l50_effect_bank_set dereferences it, and the heap/array out-of-bounds reads can trigger kernel oops/panic or KASAN faults on affected CS40L50 haptic devices."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-27T05:01:57.416Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.11","versionEndExcluding":"6.12.105"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.11","versionEndExcluding":"6.18.46"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.11","versionEndExcluding":"7.1.10"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.11","versionEndExcluding":"7.2"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}