dmaengine: idxd: Fix allowing write() from different address spaces

dmaengine: idxd: Fix allowing write() from different address spaces

[ Upstream commit 8dfa57aabff625bf445548257f7711ef294cd30e ]

Check if the process submitting the descriptor belongs to the same
address space as the one that opened the file, reject otherwise.

Fixes: 6827738dc684 ("dmaengine: idxd: add a write() method for applications to submit work")
Signed-off-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/20250421170337.3008875-1-dave.jiang@intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>