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CVE-2026-64083

hwmon: (pmbus/adm1266) reject short block-read responses in the GPIO accessors PUBLISHED

Description (CNA)

In the Linux kernel, the following vulnerability has been resolved: hwmon: (pmbus/adm1266) reject short block-read responses in the GPIO accessors adm1266_gpio_get() and adm1266_gpio_get_multiple() both compose the pin-status word as pins_status = read_buf[0] + (read_buf[1] << 8); right after i2c_smbus_read_block_data(), guarding only against an error return. A well-behaved device returns 2 bytes for GPIO_STATUS/PDIO_STATUS, but the helper happily reports a 0- or 1-byte response too. If the device returns 0 bytes, both read_buf slots are uninitialized stack memory; if it returns 1 byte, read_buf[1] is. The composed value then flows through set_bit() into the caller's *bits in adm1266_gpio_get_multiple(), or into the return value of adm1266_gpio_get(), and ends up in userspace via gpiolib (sysfs and the char-dev ioctls). That leaks a few bits of kernel stack per request on any device whose firmware glitch, bus error, or hostile slave produces a short block-read response. Add the missing length check to both call sites and surface a short response as -EIO.

Affected (CNA)

Vendor / productVersions
Linux / Linuxaffected d98dfad35c38c037b37c4adc99df01da571031a5 before fd9196aad9e5a3845cea17de3405ebc700382142; affected d98dfad35c38c037b37c4adc99df01da571031a5 before ee4799becf7d2af3778007e22c2e55c4009a49c7; affected d98dfad35c38c037b37c4adc99df01da571031a5 before c603b6c6840ac0c6285f5eefea0de6242710af21; affected d98dfad35c38c037b37c4adc99df01da571031a5 before a2d1c819348b36fccbbfcf37c5fa7a50a9b4528f; affected d98dfad35c38c037b37c4adc99df01da571031a5 before ae25cf2ea9ebd06d7ad416647dbdc7b5d0172946; affected d98dfad35c38c037b37c4adc99df01da571031a5 before eb3cd9bb590460c6127145cb245be925d23f5232; affected d98dfad35c38c037b37c4adc99df01da571031a5 before 64fa9328948ddcc0f7f3c23ea1756c126d9dffac; affected d98dfad35c38c037b37c4adc99df01da571031a5 before a7232f68c43ca62f545049b7f5fbfc75137b843b
Linux / Linuxaffected 5.10; unaffected 0 before 5.10; unaffected 5.10.258 through 5.10.*; unaffected 5.15.209 through 5.15.*; unaffected 6.1.175 through 6.1.*; unaffected 6.6.142 through 6.6.*; unaffected 6.12.92 through 6.12.*; unaffected 6.18.34 through 6.18.*; unaffected 7.0.11 through 7.0.*; unaffected 7.1 through *

CWE

No CWE identifiers supplied.

References