From:   Jiasheng Jiang <jiasheng@iscas.ac.cn>
To:     robert.moore@intel.com, rafael.j.wysocki@intel.com, lenb@kernel.org
Cc:     linux-acpi@vger.kernel.org, devel@acpica.org,
        linux-kernel@vger.kernel.org, Jiasheng Jiang <jiasheng@iscas.ac.cn>
Subject: [PATCH] ACPI/ACPICA: Check for NULL pointer after calling alloc
Date:   Fri, 14 Jan 2022 18:15:46 +0800
Message-Id: <20220114101546.1368163-1-jiasheng@iscas.ac.cn>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

As the possible failure of the allocation, object_info could be NULL
pointer.
Therefore, it should be better to check it in order to avoid the
dereference of the NULL pointer.
If fails, we should return 'AE_NON_MEMORY' and the caller
acpi_db_command_dispatch() will deal with the return status of
acpi_db_display_objects().
Also, the comment of the acpi_db_display_objects() is wrong.
So we need to correct it too.

Fixes: 995751025572 ("ACPICA: Linuxize: Export debugger files to Linux")
Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
---
 drivers/acpi/acpica/dbnames.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/acpi/acpica/dbnames.c b/drivers/acpi/acpica/dbnames.c
index 3615e1a6efd8..d8e5852fadb1 100644
--- a/drivers/acpi/acpica/dbnames.c
+++ b/drivers/acpi/acpica/dbnames.c
@@ -632,7 +632,7 @@ acpi_db_walk_for_specific_objects(acpi_handle obj_handle,
  * PARAMETERS:  obj_type_arg        - Type of object to display
  *              display_count_arg   - Max depth to display
  *
- * RETURN:      None
+ * RETURN:      Status
  *
  * DESCRIPTION: Display objects in the namespace of the requested type
  *
@@ -651,6 +651,8 @@ acpi_status acpi_db_display_objects(char *obj_type_arg, char *display_count_arg)
 	if (!obj_type_arg) {
 		object_info =
 		    ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_object_info));
+		if (!object_info)
+			return (AE_NO_MEMORY);
 
 		/* Walk the namespace from the root */
 
-- 
2.25.1