From: Yang Yingliang yangyingliang@huawei.com
[ Upstream commit 1ff36351309e3eadcff297480baf4785e726de9b ]
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: device_del+0x48/0x3a0 attribute_container_class_device_del+0x28/0x40 transport_remove_classdev+0x60/0x7c attribute_container_device_trigger+0x118/0x120 transport_remove_device+0x20/0x30 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 Signed-off-by: Damien Le Moal damien.lemoal@opensource.wdc.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/ata/libata-transport.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)
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; + } + transport_configure_device(dev); return 0; }