CVEvulnerability
CVE-2026-63934
- Status
- Undergoing Analysis
- Published
- 2026-07-19
- Last modified
- 2026-07-27
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Description
In the Linux kernel, the following vulnerability has been resolved:
iio: gyro: itg3200: fix i2c read into the wrong stack location
itg3200_read_all_channels() takes `__be16 *buf' as a parameter and
fills the i2c_msg destination as `(char *)&buf'. Since `buf' is the
parameter (a pointer), `&buf' is the address of the local pointer
slot on the stack of itg3200_read_all_channels(), not the address
of the caller's scan buffer. The (char *) cast hides the type
mismatch.
i2c_transfer() therefore writes ITG3200_SCAN_ELEMENTS * sizeof(s16)
= 8 bytes into the parameter's stack slot, which is discarded when
the function returns. The caller's scan buffer in
itg3200_trigger_handler() is never written to, so
iio_push_to_buffers_with_timestamp() pushes uninitialised stack
contents to userspace via /dev/iio:deviceX every scan -- both a
functional bug (no actual gyroscope or temperature data is
delivered through the triggered buffer) and an information leak.
The non-buffered read_raw() path is unaffected: it goes through
itg3200_read_reg_s16() which uses `&out' on a local s16 value,
where that is correct.
Drop the spurious `&' so the i2c read writes into the caller's
buffer.
References
- https://git.kernel.org/stable/c/15a0b3f33ffb6c78b3de6f69b026ceb09b973dd1 git.kernel.org
- https://git.kernel.org/stable/c/31bbd4b87dd6701fa10e03ba7f6268e49e178d16 git.kernel.org
- https://git.kernel.org/stable/c/63203bd072b613c18c237b906b1c9d2dc4527337 git.kernel.org
- https://git.kernel.org/stable/c/6bdc3023d62ed5c7d591f0eb27a5adb37fb892ae git.kernel.org
- https://git.kernel.org/stable/c/8654b5e2617819ff4f7c78071dfd0275e971a9b6 git.kernel.org
- https://git.kernel.org/stable/c/90e809376b0f0d1ddec2eec954aecdd2a5b40b0e git.kernel.org
- https://git.kernel.org/stable/c/b64dd5f3b38911054cbcc570df617e3e8e75e562 git.kernel.org
- https://git.kernel.org/stable/c/cfc3283859cfdeacadf80d5e6880bdf871ffeaa6 git.kernel.org