ACPI/IORT: Fix memory leak in iort_rmr_alloc_sids()

If krealloc_array() fails in iort_rmr_alloc_sids(), the function returns
NULL but does not free the original 'sids' allocation. This results in a
memory leak since the caller overwrites the original pointer with the
NULL return value.

Fixes: 491cf4a6735a ("ACPI/IORT: Add support to retrieve IORT RMR reserved regions")
Cc: <stable@vger.kernel.org> # 6.0.x
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Reviewed-by: Hanjun Guo <guohanjun@huawei.com>
Link: https://lore.kernel.org/r/20250828112243.61460-1-linmq006@gmail.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
index 98759d6..65f0f56 100644
--- a/drivers/acpi/arm64/iort.c
+++ b/drivers/acpi/arm64/iort.c
@@ -937,8 +937,10 @@ static u32 *iort_rmr_alloc_sids(u32 *sids, u32 count, u32 id_start,
 
 	new_sids = krealloc_array(sids, count + new_count,
 				  sizeof(*new_sids), GFP_KERNEL);
-	if (!new_sids)
+	if (!new_sids) {
+		kfree(sids);
 		return NULL;
+	}
 
 	for (i = count; i < total_count; i++)
 		new_sids[i] = id_start++;