CVE-2026-63965iio: pressure: bmp280: fix stack leak in bmp580 trigger handler

Official description

In the Linux kernel, the following vulnerability has been resolved: iio: pressure: bmp280: fix stack leak in bmp580 trigger handler bmp580_trigger_handler() declares its scan buffer on the stack without an initializer and then memcpy()s 3 bytes of 24-bit sensor data into each 4-byte __le32 field. The high byte of comp_temp and comp_press is left uninitialized, and the channel storagebits is 32, so two bytes of stack are pushed to userspace per scan. This is a regression from when the buffer lived in the private data, the move to a stack-local struct dropped the implicit zeroing. bme280_trigger_handler() was fixed up to handle this bug, but this driver was not fixed because there was no padding hole, but rather a short-fill issue. Fix this all by just zero-initializing the structure on the stack.

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/a58400f58f82f3d8de9c067aa7cda690228c1ecc
• https://git.kernel.org/stable/c/58dfb6fe9dc80270cf7cc014837af4cbf928e3aa
• https://git.kernel.org/stable/c/387c86b582e0782ab332e7bfcd4e6e3f93922961