Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
mtd: Fix gluebi NULL pointer dereference caused by ftl notifier
If both ftl.ko and gluebi.ko are loaded, the notifier of ftl triggers NULL pointer dereference when trying to access ‘gluebi->desc’ in gluebi_read().
ubi_gluebi_init ubi_register_volume_notifier ubi_enumerate_volumes ubi_notify_all gluebi_notify nb->notifier_call() gluebi_create mtd_device_register mtd_device_parse_register add_mtd_device blktrans_notify_add not->add() ftl_add_mtd tr->add_mtd() scan_header mtd_read mtd_read_oob mtd_read_oob_std gluebi_read mtd->read() gluebi->desc - NULL
Detailed reproduction information available at the Link [1],
In the normal case, obtain gluebi->desc in the gluebi_get_device(), and access gluebi->desc in the gluebi_read(). However, gluebi_get_device() is not executed in advance in the ftl_add_mtd() process, which leads to NULL pointer dereference.
The solution for the gluebi module is to run jffs2 on the UBI volume without considering working with ftl or mtdblock [2]. Therefore, this problem can be avoided by preventing gluebi from creating the mtdblock device after creating mtd partition of the type MTD_UBIVOLUME.
Details
- Affected product:
- AlmaLinux 9.2 ESU , Amazon Linux 2 ELS , CentOS 6 ELS , CentOS 7 ELS , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , CloudLinux 6 ELS , CloudLinux 7 ELS , Debian 10 ELS , Oracle Linux 6 ELS , Oracle Linux 7 ELS , RHEL 7 ELS , TuxCare 9.6 ESU , Ubuntu 16.04 ELS , Ubuntu 18.04 ELS , Ubuntu 20.04 ELS
- Affected packages:
- linux @ 4.15.0 (+18 more)
Fixes
KernelCare state
Live-patch status from KernelCare for each operating system.
| Operating system | Status | Covered kernels |
|---|---|---|
| Debian 10 | Will Not Fix | — |
| Debian 10 cloud | Will Not Fix | — |
| Proxmox VE 6 | Released |
41 kernels
|
| Proxmox VE 7 5.15 | Released |
43 kernels
|
| Ubuntu 14.04 HWE ESM | Will Not Fix | — |
| Ubuntu 16.04 | Released |
13 kernels
|
| Ubuntu 16.04 AWS ESM | Will Not Fix | — |
| Ubuntu 16.04 AWS HWE ESM | Will Not Fix | — |
| Ubuntu 16.04 Azure ESM | Will Not Fix | — |
| Ubuntu 16.04 ESM | Will Not Fix | — |
| Ubuntu 16.04 GCP ESM | Will Not Fix | — |
| Ubuntu 16.04 HWE ESM | Will Not Fix | — |
| Ubuntu 18.04 | Released |
9 kernels
|
| Ubuntu 18.04 AWS | Will Not Fix | — |
| Ubuntu 18.04 AWS Focal | Released |
56 kernels
|
| Ubuntu 18.04 Azure Focal | Released |
58 kernels
|
| Ubuntu 18.04 HWE Focal | Released |
69 kernels
|
| Ubuntu 18.04 HWE GCP | Released |
15 kernels
|
| Ubuntu 20.04 | Released |
104 kernels
|
| Ubuntu 20.04 AWS | Released |
87 kernels
|
| Ubuntu 20.04 Azure | Released |
78 kernels
|
| Ubuntu 20.04 GCP | Released |
10 kernels
|
| Ubuntu 20.04 HWE AWS | Released |
35 kernels
|
| Ubuntu 20.04 HWE Azure | Released |
19 kernels
|
| Ubuntu 22.04 | Released |
48 kernels
|
| Ubuntu 22.04 AWS | Released |
42 kernels
|
| Ubuntu 22.04 Azure | Released |
39 kernels
|