[PATCH] ACPI: tables: handle failed initrd override mappings

[Slavin Liu]

The runtime AML table-loading path can invoke initrd override after
permanent mappings are enabled. Mapping bookkeeping can then fail.
Return AE_NO_MEMORY before reading the candidate header through NULL.

Detected by static analysis and reviewed with AI-assisted source auditing.

Fixes: b2a35003dfbc ("ACPI: Implement physical address table override")
Assisted-by: LLM
Signed-off-by: Slavin Liu <bolin.liu@xxxxxxxxxx>
---
 drivers/acpi/tables.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/acpi/tables.c b/drivers/acpi/tables.c
index eb93c060426f..749a128a889c 100644
--- a/drivers/acpi/tables.c
+++ b/drivers/acpi/tables.c
@@ -560,6 +560,8 @@ acpi_table_initrd_override(struct acpi_table_header *existing_table,
 	while (table_offset + ACPI_HEADER_SIZE <= all_tables_size) {
 		table = acpi_os_map_memory(acpi_tables_addr + table_offset,
 					   ACPI_HEADER_SIZE);
+		if (!table)
+			return AE_NO_MEMORY;
 		if (table_offset + table->length > all_tables_size) {
 			acpi_os_unmap_memory(table, ACPI_HEADER_SIZE);
 			WARN_ON(1);