CVE-2026-64501

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

iio: adc: ad_sigma_delta: fix CS held asserted and state leaks

In ad_sigma_delta_single_conversion(), set_mode(AD_SD_MODE_IDLE) and

disable_one() were called from the out: block while keep_cs_asserted

was still true. This caused any SPI transfer issued by those callbacks

to carry cs_change=1, leaving CS permanently asserted after the

conversion. Fix by moving both calls into the out_unlock: block, after

keep_cs_asserted is cleared, matching the pattern already used in

ad_sd_calibrate().

In the error path of ad_sd_buffer_postenable(), if an operation fails

after set_mode(AD_SD_MODE_CONTINUOUS) has already succeeded (e.g.

spi_offload_trigger_enable()), the device is left in continuous

conversion mode with CS physically asserted. Additionally,

bus_locked remaining true after spi_bus_unlock() causes subsequent

SPI operations to call spi_sync_locked() without the bus lock actually

held, allowing concurrent SPI access.

Fix the error path by clearing keep_cs_asserted first, then calling

set_mode(AD_SD_MODE_IDLE) to revert the device mode and deassert CS,

then clearing bus_locked before releasing the bus.

For devices that implement neither set_mode nor disable_one (such as

MAX11205, which has no physical CS pin), no SPI transfer is issued

during cleanup and the cs_change flag has no effect on any physical

line.