CVE-2022-48697

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

nvmet: fix a use-after-free

Fix the following use-after-free complaint triggered by blktests nvme/004:

BUG: KASAN: user-memory-access in blk_mq_complete_request_remote+0xac/0x350 Read of size 4 at addr 0000607bd1835943 by task kworker/13:1/460 Workqueue: nvmet-wq nvme_loop_execute_work [nvme_loop] Call Trace: show_stack+0x52/0x58 dump_stack_lvl+0x49/0x5e print_report.cold+0x36/0x1e2 kasan_report+0xb9/0xf0 __asan_load4+0x6b/0x80 blk_mq_complete_request_remote+0xac/0x350 nvme_loop_queue_response+0x1df/0x275 [nvme_loop] __nvmet_req_complete+0x132/0x4f0 [nvmet] nvmet_req_complete+0x15/0x40 [nvmet] nvmet_execute_io_connect+0x18a/0x1f0 [nvmet] nvme_loop_execute_work+0x20/0x30 [nvme_loop] process_one_work+0x56e/0xa70 worker_thread+0x2d1/0x640 kthread+0x183/0x1c0 ret_from_fork+0x1f/0x30

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/17f121ca3ec6be0fb32d77c7f65362934a38cc8e
• https://git.kernel.org/stable/c/4484ce97a78171668c402e0c45db7f760aea8060
• https://git.kernel.org/stable/c/6a02a61e81c231cc5c680c5dbf8665275147ac52
• https://git.kernel.org/stable/c/8d66989b5f7bb28bba2f8e1e2ffc8bfef4a10717
• https://git.kernel.org/stable/c/be01f1c988757b95f11f090a9f491365670a522b
• https://git.kernel.org/stable/c/ebf46da50beb78066674354ad650606a467e33fa
• https://git.kernel.org/stable/c/17f121ca3ec6be0fb32d77c7f65362934a38cc8e
• https://git.kernel.org/stable/c/4484ce97a78171668c402e0c45db7f760aea8060
• https://git.kernel.org/stable/c/6a02a61e81c231cc5c680c5dbf8665275147ac52
• https://git.kernel.org/stable/c/8d66989b5f7bb28bba2f8e1e2ffc8bfef4a10717
• https://git.kernel.org/stable/c/be01f1c988757b95f11f090a9f491365670a522b
• https://git.kernel.org/stable/c/ebf46da50beb78066674354ad650606a467e33fa