Files
linux/drivers/s390
Salah Triki f65c75b0b9 s390/cio: Fix device lifecycle handling in css_alloc_subchannel()
`css_alloc_subchannel()` calls `device_initialize()` before setting up
the DMA masks. If `dma_set_coherent_mask()` or `dma_set_mask()` fails,
the error path frees the subchannel structure directly, bypassing
the device model reference counting.

Once `device_initialize()` has been called, the embedded struct device
must be released via `put_device()`, allowing the release callback to
free the container structure.

Fix the error path by dropping the initial device reference with
`put_device()` instead of calling `kfree()` directly.

This ensures correct device lifetime handling and avoids potential
use-after-free or double-free issues.

Fixes: e5dcf0025d ("s390/css: move subchannel lock allocation")
Signed-off-by: Salah Triki <salah.triki@gmail.com>
Reviewed-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2026-02-05 13:02:48 +01:00
..
2025-11-24 11:45:21 +01:00