From 3613dbe3909dcc637fe6be00e4dc43b4aa0470ee Mon Sep 17 00:00:00 2001 From: Yang Yingliang Date: Tue, 8 Nov 2022 21:40:02 +0800 Subject: ata: libata-transport: fix error handling in ata_tport_add() In ata_tport_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: 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 Signed-off-by: Damien Le Moal --- 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: -- cgit v1.2.3-70-g09d2