Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved: SUNRPC: make sure cache entry active before cache_show The functionc_show was called with protection from RCU. This only
ensures that cp will not be freed. Therefore, the reference count for
cp can drop to zero, which will trigger a refcount use-after-free
warning when cache_get is called. To resolve this issue, use
cache_get_rcu to ensure that cp remains active.
————[ cut here ]————
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 7 PID: 822 at lib/refcount.c:25
refcount_warn_saturate+0xb1/0x120
CPU: 7 UID: 0 PID: 822 Comm: cat Not tainted 6.12.0-rc3+ #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
1.16.1-2.fc37 04/01/2014
RIP: 0010:refcount_warn_saturate+0xb1/0x120
Call Trace:
<TASK>
c_show+0x2fc/0x380 [sunrpc]
seq_read_iter+0x589/0x770
seq_read+0x1e5/0x270
proc_reg_read+0xe1/0x140
vfs_read+0x125/0x530
ksys_read+0xc1/0x160
do_syscall_64+0x5f/0x170
entry_SYSCALL_64_after_hwframe+0x76/0x7e
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 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:
- kernel @ 5.10.0 (+17 more)
Fixes
KernelCare state
Live-patch status from KernelCare for each operating system.
| Operating system | Status | Covered kernels |
|---|---|---|
| AlmaLinux 9 | Released |
50 kernels
|
| AlmaLinux 9.2 ESU | Ready For Release | — |
| Amazon Linux 2023 | Planned | — |
| Amazon Linux 2 5.10 | Will Not Fix | — |
| Amazon Linux 2 5.4 | Will Not Fix | — |
| CentOS 7 ELS | Released |
19 kernels
|
| Debian 11 | Planned | — |
| Debian 11 cloud | Planned | — |
| Debian 12 | Planned | — |
| Oracle Linux 7 UEK 6 | Released |
112 kernels
|
| Oracle Linux 8 UEK 6 | Released |
116 kernels
|
| Oracle Linux 8 UEK 7 | Released |
53 kernels
|
| Oracle Linux 9 | Released |
56 kernels
|
| Oracle Linux 9 UEK 7 | Released |
53 kernels
|
| RHEL 9 | Released |
50 kernels
|
| Rocky Linux 9 | Released |
49 kernels
|
| Ubuntu 18.04 AWS Focal | Will Not Fix | — |
| Ubuntu 20.04 | Ready For Release | — |
| Ubuntu 22.04 | In Progress | — |
| Ubuntu 22.04 AWS | In Progress | — |
| Ubuntu 22.04 Azure | In Progress | — |
| Ubuntu 24.04 | Released |
20 kernels
|
| Ubuntu 24.04 AWS | Ready For Release | — |