Overview
About vulnerability
In the Linux kernel, the following vulnerability has been resolved:
nfc: llcp: read llcp_sock->local under the socket lock in getsockopt
nfc_llcp_getsockopt() read llcp_sock->local before lock_sock(sk) and then dereferenced the cached pointer inside the locked region. llcp_sock_bind() assigns and clears llcp_sock->local under the same socket lock, dropping the last reference on its error path. A getsockopt() racing an in-flight bind() can observe the pointer, block on lock_sock(), and then dereference a freed nfc_llcp_local once bind() has unwound.
Move the llcp_sock->local read and the NULL check inside the lock_sock(sk) region so bind() cannot mutate or free the pointer between the load and the use.
Details
- Affected product:
- AlmaLinux 9.2 ESU , Amazon Linux 2 ELS , CentOS 7 ELS , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , CloudLinux 7 ELS , Debian 10 ELS , Debian 11 ELS , Oracle Linux 7 ELS , RHEL 7 ELS , TuxCare 9.6 ESU , TuxCare 9.8 ESU , Ubuntu 16.04 ELS , Ubuntu 18.04 ELS , Ubuntu 20.04 ELS
- Affected packages:
- linux @ 5.4.0 (+17 more)
Fixes
KernelCare state
Live-patch status from KernelCare for each operating system.
| Operating system | Status | Covered kernels |
|---|---|---|
| Debian 12 | Planned | — |
| Debian 13 | Released |
17 kernels
|