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From: Yang Yingliang <yangyingliang@huawei.com>
Date: Wed, 9 Nov 2022 11:24:03 +0800
Subject: scsi: mpt3sas: Fix possible resource leaks in
 mpt3sas_transport_port_add()
Git-commit: 78316e9dfc24906dd474630928ed1d3c562b568e
Patch-mainline: v6.2-rc1
References: git-fixes

In mpt3sas_transport_port_add(), if sas_rphy_add() returns error,
sas_rphy_free() needs be called to free the resource allocated in
sas_end_device_alloc(). Otherwise a kernel crash will happen:

Unable to handle kernel NULL pointer dereference at virtual address 0000000000000108
CPU: 45 PID: 37020 Comm: bash Kdump: loaded Tainted: G        W          6.1.0-rc1+ #189
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_rphy_remove+0x50/0x78 [scsi_transport_sas]
 sas_port_delete+0x30/0x148 [scsi_transport_sas]
 do_sas_phy_delete+0x78/0x80 [scsi_transport_sas]
 device_for_each_child+0x68/0xb0
 sas_remove_children+0x30/0x50 [scsi_transport_sas]
 sas_rphy_remove+0x38/0x78 [scsi_transport_sas]
 sas_port_delete+0x30/0x148 [scsi_transport_sas]
 do_sas_phy_delete+0x78/0x80 [scsi_transport_sas]
 device_for_each_child+0x68/0xb0
 sas_remove_children+0x30/0x50 [scsi_transport_sas]
 sas_remove_host+0x20/0x38 [scsi_transport_sas]
 scsih_remove+0xd8/0x420 [mpt3sas]

Because transport_add_device() is not called when sas_rphy_add() fails, the
device is not added. When sas_rphy_remove() is subsequently called to
remove the device in the remove() path, a NULL pointer dereference happens.

Fixes: f92363d12359 ("[SCSI] mpt3sas: add new driver supporting 12GB SAS")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20221109032403.1636422-1-yangyingliang@huawei.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Lee Duncan <lduncan@suse.com>
---
 drivers/scsi/mpt3sas/mpt3sas_transport.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/scsi/mpt3sas/mpt3sas_transport.c b/drivers/scsi/mpt3sas/mpt3sas_transport.c
index 0681daee6c14..e5ecd6ada6cd 100644
--- a/drivers/scsi/mpt3sas/mpt3sas_transport.c
+++ b/drivers/scsi/mpt3sas/mpt3sas_transport.c
@@ -829,6 +829,8 @@ mpt3sas_transport_port_add(struct MPT3SAS_ADAPTER *ioc, u16 handle,
 	if ((sas_rphy_add(rphy))) {
 		ioc_err(ioc, "failure at %s:%d/%s()!\n",
 			__FILE__, __LINE__, __func__);
+		sas_rphy_free(rphy);
+		rphy = NULL;
 	}
 
 	if (mpt3sas_port->remote_identify.device_type == SAS_END_DEVICE) {