From 5d7bebf2dfb0dc97aac1fbace0910e557ecdb16f Mon Sep 17 00:00:00 2001 From: Yang Yingliang Date: Mon, 7 Nov 2022 20:48:28 +0800 Subject: [PATCH] scsi: scsi_transport_sas: Fix error handling in sas_phy_add() If transport_add_device() fails in sas_phy_add(), the kernel will crash trying to delete the device in transport_remove_device() called from sas_remove_host(). Unable to handle kernel NULL pointer dereference at virtual address 0000000000000108 CPU: 61 PID: 42829 Comm: rmmod Kdump: loaded Tainted: G W 6.1.0-rc1+ #173 pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : device_del+0x54/0x3d0 lr : device_del+0x37c/0x3d0 Call trace: device_del+0x54/0x3d0 attribute_container_class_device_del+0x28/0x38 transport_remove_classdev+0x6c/0x80 attribute_container_device_trigger+0x108/0x110 transport_remove_device+0x28/0x38 sas_phy_delete+0x30/0x60 [scsi_transport_sas] do_sas_phy_delete+0x6c/0x80 [scsi_transport_sas] device_for_each_child+0x68/0xb0 sas_remove_children+0x40/0x50 [scsi_transport_sas] sas_remove_host+0x20/0x38 [scsi_transport_sas] hisi_sas_remove+0x40/0x68 [hisi_sas_main] hisi_sas_v2_remove+0x20/0x30 [hisi_sas_v2_hw] platform_remove+0x2c/0x60 Fix this by checking and handling return value of transport_add_device() in sas_phy_add(). Fixes: c7ebbbce366c ("[SCSI] SAS transport class") Suggested-by: John Garry Signed-off-by: Yang Yingliang Link: https://lore.kernel.org/r/20221107124828.115557-1-yangyingliang@huawei.com Reviewed-by: John Garry Reviewed-by: Jason Yan Signed-off-by: Martin K. Petersen --- drivers/scsi/scsi_transport_sas.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/drivers/scsi/scsi_transport_sas.c b/drivers/scsi/scsi_transport_sas.c index 2f88c61..74b99f2 100644 --- a/drivers/scsi/scsi_transport_sas.c +++ b/drivers/scsi/scsi_transport_sas.c @@ -722,12 +722,17 @@ int sas_phy_add(struct sas_phy *phy) int error; error = device_add(&phy->dev); - if (!error) { - transport_add_device(&phy->dev); - transport_configure_device(&phy->dev); + if (error) + return error; + + error = transport_add_device(&phy->dev); + if (error) { + device_del(&phy->dev); + return error; } + transport_configure_device(&phy->dev); - return error; + return 0; } EXPORT_SYMBOL(sas_phy_add); -- 2.7.4