In ata_tport_add(), the return value of transport_add_device() is not
checked. As a result, another error after that function call leads to
a kernel crash (null-ptr-deref) because transport_remove_device() is
called to remove a device that was not added.
Unable to handle kernel NULL pointer dereference at virtual address 00000000000000d0
CPU: 12 PID: 13605 Comm: rmmod Kdump: loaded Tainted: G W 6.1.0-rc3+ #8
pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : device_del+0x48/0x39c
lr : device_del+0x44/0x39c
Call trace:
device_del+0x48/0x39c
attribute_container_class_device_del+0x28/0x40
transport_remove_classdev+0x60/0x7c
attribute_container_device_trigger+0x118/0x120
transport_remove_device+0x20/0x30
ata_tport_delete+0x34/0x60 [libata]
ata_port_detach+0x148/0x1b0 [libata]
ata_pci_remove_one+0x50/0x80 [libata]
ahci_remove_one+0x4c/0x8c [ahci]
Fix this by checking and handling return value of transport_add_device()
in ata_tport_add().
Fixes: d9027470b886 ("[libata] Add ATA transport class")
Signed-off-by: Yang Yingliang <yangyingliang@xxxxxxxxxx>
---
drivers/ata/libata-transport.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/ata/libata-transport.c b/drivers/ata/libata-transport.c
index 105da3ec5eaa..ef53bdfbcbb2 100644
--- a/drivers/ata/libata-transport.c
+++ b/drivers/ata/libata-transport.c
@@ -301,7 +301,9 @@ int ata_tport_add(struct device *parent,
pm_runtime_enable(dev);
pm_runtime_forbid(dev);
- transport_add_device(dev);
+ error = transport_add_device(dev);
+ if (error)
+ goto tport_transport_add_err;
transport_configure_device(dev);
error = ata_tlink_add(&ap->link);
@@ -312,6 +314,7 @@ int ata_tport_add(struct device *parent,
tport_link_err:
transport_remove_device(dev);
+ tport_transport_add_err:
device_del(dev);
tport_err:
--
2.25.1
