FROMLIST: misc: fastrpc: Fail Audio PD init when reserved memory is missing

Audio PD static process creation assumes that a reserved-memory
region is defined in DT and exposed via cctx->remote_heap.

If reserved-memory is missing or incomplete, the driver may pass
invalid address/size information to the DSP, leading to undefined
behavior or crashes.

Add explicit validation for remote_heap presence and size before
sending the memory to DSP, and fail early if the configuration is
invalid.

Link: https://lore.kernel.org/all/20260526111124.515-4-jianping.li@oss.qualcomm.com/
Fixes: 0871561 ("misc: fastrpc: Add support for audiopd")
Cc: stable@kernel.org
Signed-off-by: Jianping Li <jianping.li@oss.qualcomm.com>
Signed-off-by: Vinayak Katoch <vkatoch@qti.qualcomm.com>

Author: Jianping-Li

drivers/misc/fastrpc.c

@@ -1469,6 +1469,13 @@ static int fastrpc_init_create_static_process(struct fastrpc_user *fl,
 	} inbuf;
 	u32 sc;
 
+	if (!fl->cctx->remote_heap ||
+	    !fl->cctx->remote_heap->dma_addr ||
+	    !fl->cctx->remote_heap->size) {
+		err = -ENOMEM;
+		dev_dbg(fl->sctx->dev, "remote heap memory region is not added\n");
+		return err;
+	}
 	args = kzalloc_objs(*args, FASTRPC_CREATE_STATIC_PROCESS_NARGS);
 	if (!args)
 		return -ENOMEM;