CVE-2022-48924

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

thermal: int340x: fix memory leak in int3400_notify()

It is easy to hit the below memory leaks in my TigerLake platform:

unreferenced object 0xffff927c8b91dbc0 (size 32): comm kworker/0:2, pid 112, jiffies 4294893323 (age 83.604s) hex dump (first 32 bytes): 4e 41 4d 45 3d 49 4e 54 33 34 30 30 20 54 68 65 NAME=INT3400 The 72 6d 61 6c 00 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b a5 rmal.kkkkkkkkkk. backtrace: [] __kmalloc_track_caller+0x2fe/0x4a0 [] kvasprintf+0x65/0xd0 [] kasprintf+0x4e/0x70 [] int3400_notify+0x82/0x120 [int3400_thermal] [] acpi_ev_notify_dispatch+0x54/0x71 [] acpi_os_execute_deferred+0x17/0x30 [] process_one_work+0x21a/0x3f0 [] worker_thread+0x4a/0x3b0 [] kthread+0xfd/0x130 [] ret_from_fork+0x1f/0x30

Fix it by calling kfree() accordingly.

Weakness

The product does not sufficiently track and release allocated memory after it has been used, which slowly consumes remaining memory.

Affected Software

Potential Mitigations

• Choose a language or tool that provides automatic memory management, or makes manual memory management less error-prone.
• For example, glibc in Linux provides protection against free of invalid pointers.
• When using Xcode to target OS X or iOS, enable automatic reference counting (ARC) [REF-391].
• To help correctly and consistently manage memory when programming in C++, consider using a smart pointer class such as std::auto_ptr (defined by ISO/IEC ISO/IEC 14882:2003), std::shared_ptr and std::unique_ptr (specified by an upcoming revision of the C++ standard, informally referred to as C++ 1x), or equivalent solutions such as Boost.

References

• https://git.kernel.org/stable/c/2e798814e01827871938ff172d2b2ccf1e74b355
• https://git.kernel.org/stable/c/33c73a4d7e7b19313a6b417152f5365016926418
• https://git.kernel.org/stable/c/3abea10e6a8f0e7804ed4c124bea2d15aca977c8
• https://git.kernel.org/stable/c/ba9efbbf6745750d34c1e87c9539ce9db645ca0a
• https://git.kernel.org/stable/c/c3fa6d1937a8d0828131a04ae2cd2c30d0668693
• https://git.kernel.org/stable/c/e098933866f9e1dd3ef4eebbe2e3d504f970f599
• https://git.kernel.org/stable/c/f0ddc5184b0127038d05008e2a69f89d1e13f980