dmaengine: validate dev and name in dma_request_chan()

dma_request_chan() assumes both @dev and @name are valid, but neither is
checked before use.

dev is dereferenced immediately via dev_fwnode(), which accesses
dev->of_node or dev->fwnode without checking for NULL. Likewise, if name is
NULL and the OF/ACPI lookup does not succeed, the legacy filter-map path
eventually passes it to strcmp(), resulting in a NULL pointer dereference.

These are caller bugs rather than normal lookup failures, so add a
WARN_ON() at function entry to catch invalid arguments early during
development instead of crashing later.

No functional change for valid callers.

Signed-off-by: bui duc phuc <phucduc.bui@gmail.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Link: https://patch.msgid.link/20260716052758.23465-1-phucduc.bui@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
This commit is contained in:
bui duc phuc 2026-07-16 12:27:58 +07:00 • committed by Vinod Koul
commit dc8a5238e1