Attacker Value
Unknown
(0 users assessed)
Exploitability
Unknown
(0 users assessed)
User Interaction
Unknown
Privileges Required
Unknown
Attack Vector
Unknown
0

CVE-2024-50296

Disclosure Date: November 19, 2024 •
CVE-2024-50296
Add MITRE ATT&CK tactics and techniques that apply to this CVE.

Description

In the Linux kernel, the following vulnerability has been resolved:

net: hns3: fix kernel crash when uninstalling driver

When the driver is uninstalled and the VF is disabled concurrently, a
kernel crash occurs. The reason is that the two actions call function
pci_disable_sriov(). The num_VFs is checked to determine whether to
release the corresponding resources. During the second calling, num_VFs
is not 0 and the resource release function is called. However, the
corresponding resource has been released during the first invoking.
Therefore, the problem occurs:

[15277.839633][T50670] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000020
…
[15278.131557][T50670] Call trace:
[15278.134686][T50670] klist_put+0x28/0x12c
[15278.138682][T50670] klist_del+0x14/0x20
[15278.142592][T50670] device_del+0xbc/0x3c0
[15278.146676][T50670] pci_remove_bus_device+0x84/0x120
[15278.151714][T50670] pci_stop_and_remove_bus_device+0x6c/0x80
[15278.157447][T50670] pci_iov_remove_virtfn+0xb4/0x12c
[15278.162485][T50670] sriov_disable+0x50/0x11c
[15278.166829][T50670] pci_disable_sriov+0x24/0x30
[15278.171433][T50670] hnae3_unregister_ae_algo_prepare+0x60/0x90 [hnae3]
[15278.178039][T50670] hclge_exit+0x28/0xd0 [hclge]
[15278.182730][T50670] __se_sys_delete_module.isra.0+0x164/0x230
[15278.188550][T50670] __arm64_sys_delete_module+0x1c/0x30
[15278.193848][T50670] invoke_syscall+0x50/0x11c
[15278.198278][T50670] el0_svc_common.constprop.0+0x158/0x164
[15278.203837][T50670] do_el0_svc+0x34/0xcc
[15278.207834][T50670] el0_svc+0x20/0x30

For details, see the following figure.

 rmmod hclge              disable VFs

hclge_exit() sriov_numvfs_store()
… device_lock()
pci_disable_sriov() hns3_pci_sriov_configure()

                        pci_disable_sriov()
                          sriov_disable()
sriov_disable()             if !num_VFs :
  if !num_VFs :               return;
    return;                 sriov_del_vfs()
  sriov_del_vfs()             ...
    ...                       klist_put()
    klist_put()               ...
    ...                     num_VFs = 0;
  num_VFs = 0;        device_unlock();

In this patch, when driver is removing, we get the device_lock()
to protect num_VFs, just like sriov_numvfs_store().

Add Assessment

No one has assessed this topic. Be the first to add your voice to the community.

CVSS V3 Severity and Metrics
Base Score:
None
Impact Score:
Unknown
Exploitability Score:
Unknown
Vector:
Unknown
Attack Vector (AV):
Unknown
Attack Complexity (AC):
Unknown
Privileges Required (PR):
Unknown
User Interaction (UI):
Unknown
Scope (S):
Unknown
Confidentiality (C):
Unknown
Integrity (I):
Unknown
Availability (A):
Unknown

General Information

Offensive Application
Unknown
Utility Class
Unknown
Ports
Unknown
OS
Unknown
Vulnerable Versions
Linux a0df055775f3
Linux 7ae4e56de7db
Linux 590a4b2d4e0b
Linux e36482b222e0
Linux not down converted
Prerequisites
Unknown
Discovered By
Unknown
PoC Author
Unknown
Metasploit Module
Unknown
Reporter
Unknown

Vendors

  • Linux

Products

  • Linux
Technical Analysis