CVE-2023-52769

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

wifi: ath12k: fix htt mlo-offset event locking

The ath12k active pdevs are protected by RCU but the htt mlo-offset event handling code calling ath12k_mac_get_ar_by_pdev_id() was not marked as a read-side critical section.

Mark the code in question as an RCU read-side critical section to avoid any potential use-after-free issues.

Compile tested only.

Weakness

Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code.

Affected Software

Extended Description

The use of previously-freed memory can have any number of adverse consequences, ranging from the corruption of valid data to the execution of arbitrary code, depending on the instantiation and timing of the flaw. The simplest way data corruption may occur involves the system’s reuse of the freed memory. Use-after-free errors have two common and sometimes overlapping causes:

In this scenario, the memory in question is allocated to another pointer validly at some point after it has been freed. The original pointer to the freed memory is used again and points to somewhere within the new allocation. As the data is changed, it corrupts the validly used memory; this induces undefined behavior in the process. If the newly allocated data happens to hold a class, in C++ for example, various function pointers may be scattered within the heap data. If one of these function pointers is overwritten with an address to valid shellcode, execution of arbitrary code can be achieved.

Potential Mitigations

References

• https://git.kernel.org/stable/c/6afc57ea315e0f660b1f870a681737bb7b71faef
• https://git.kernel.org/stable/c/afd3425bd69610f318403084fe491e24a1357fb9
• https://git.kernel.org/stable/c/d908ca431e20b0e4bfc5d911d1744910ed779bdb