diff mbox series

[v3,4/4] ata: libata-transport: fix error handling in ata_tdev_add()

Message ID 20221108134004.1079981-5-yangyingliang@huawei.com
State New
Headers show
Series ata: libata-transport: fix some error handlings | expand

Commit Message

Yang Yingliang Nov. 8, 2022, 1:40 p.m. UTC
In ata_tdev_add(), the return value of transport_add_device() is
not checked. As a result, it causes null-ptr-deref while removing
the module, because transport_remove_device() is called to remove
the device that was not added.

Unable to handle kernel NULL pointer dereference at virtual address 00000000000000d0
CPU: 13 PID: 13603 Comm: rmmod Kdump: loaded Tainted: G        W          6.1.0-rc3+ #36
pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : device_del+0x48/0x3a0
lr : device_del+0x44/0x3a0
Call trace:
 ata_tdev_delete+0x24/0x50 [libata]
 ata_tlink_delete+0x40/0xa0 [libata]
 ata_tport_delete+0x2c/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_tdev_add(). In the error path, device_del() is called to delete
the device which was added earlier in this function, and ata_tdev_free()
is called to free ata_dev.

Fixes: d9027470b886 ("[libata] Add ATA transport class")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
 drivers/ata/libata-transport.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)
diff mbox series


diff --git a/drivers/ata/libata-transport.c b/drivers/ata/libata-transport.c
index aac9336e8153..e4fb9d1b9b39 100644
--- a/drivers/ata/libata-transport.c
+++ b/drivers/ata/libata-transport.c
@@ -713,7 +713,13 @@  static int ata_tdev_add(struct ata_device *ata_dev)
 		return error;
-	transport_add_device(dev);
+	error = transport_add_device(dev);
+	if (error) {
+		device_del(dev);
+		ata_tdev_free(ata_dev);
+		return error;
+	}
 	return 0;