diff mbox series

[5.10,053/120] thunderbolt: Fix possible NULL pointer dereference in tb_acpi_add_link()

Message ID 20210208145820.540535458@linuxfoundation.org
State New
Headers show
Series None | expand

Commit Message

Greg KH Feb. 8, 2021, 3 p.m. UTC 
From: Mario Limonciello <mario.limonciello@dell.com>

commit 4d395c5e74398f664405819330e5a298da37f655 upstream.

When we walk up the device hierarchy in tb_acpi_add_link() make sure we
break the loop if the device has no parent. Otherwise we may crash the
kernel by dereferencing a NULL pointer.

Fixes: b2be2b05cf3b ("thunderbolt: Create device links from ACPI description")
Cc: stable@vger.kernel.org
Signed-off-by: Mario Limonciello <mario.limonciello@dell.com>
Acked-by: Yehezkel Bernat <YehezkelShB@gmail.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/thunderbolt/acpi.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff mbox series

Patch

--- a/drivers/thunderbolt/acpi.c
+++ b/drivers/thunderbolt/acpi.c
@@ -56,7 +56,7 @@  static acpi_status tb_acpi_add_link(acpi
 	 * managed with the xHCI and the SuperSpeed hub so we create the
 	 * link from xHCI instead.
 	 */
-	while (!dev_is_pci(dev))
+	while (dev && !dev_is_pci(dev))
 		dev = dev->parent;
 
 	if (!dev)