CVE-2026-64259

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> fuse-uring: make a fuse_req on SQE commit only findable after memcpy<br /> <br /> Bad userspace might try to trick us and send commit SQEs request<br /> unique / commit-id of requests that are not even send to<br /> fuse-server (io_uring_cmd_done() not called) yet.<br /> <br /> fuse_uring_commit_fetch() ends the fuse request when the ring entry<br /> has a wrong state, but that could have caused a use-after-free<br /> with the memcpy operations in fuse_uring_send_in_task().<br /> In order to avoid such races the call of fuse_uring_add_to_pq()<br /> is moved after the copy operations and just before completing<br /> the io-uring request - malicious userspace cannot find the request<br /> anymore until all prepration work in fuse-client/kernel is completed.<br /> <br /> This also moves fuse_uring_add_to_pq() a bit up in the code to<br /> avoid a forward declaration. Also not with a preparation commit,<br /> to make it easier to back port to older kernels.