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
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.