Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
s390/dasd: Do not complete a failed ESE read as successful
dasd_int_handler() completes an NRF read of an unallocated ESE track by calling ese_read() and unconditionally marking the request DASD_CQR_SUCCESS. dasd_eckd_ese_read() can return an error before it has zeroed the destination buffer: a failed sense-data parse or a current track outside the requested range both return early, leaving the destination pages untouched. The request is still completed successfully, so the block layer is handed stale / uninitialized memory instead of zeros.
Check the ese_read() return value and fail the request through the normal error path instead of forcing DASD_CQR_SUCCESS.
Details
- Affected product:
- Debian 10 ELS , Debian 11 ELS
- Affected packages:
- linux @ 5.10.259 (+1 more)