{"id":"CVE-2026-98858","published":"2026-10-18T16:17:40.257","lastModified":"2026-10-19T10:19:49.880","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nio_uring: fix task_work add use-after-free with SQPOLL\n\nFor SQPOLL, the sqpoll thread runs task_work off its own list and\ndoesn't need to be told about it, so it can pop and complete a request\nas soon as mpscq_push() has published it. If that was the last request\nholding the ring alive, io_ring_exit_work() then frees the ctx, stops\nthe thread, and with it the tctx, while io_req_normal_work_add() is\nstill looking at both after the push:\n\n  BUG: KASAN: slab-use-after-free in io_req_normal_work_add+0x439/0x510\n  Read of size 4 at addr ff11000000ca0000 by task repro/55\n  (...)\n  BUG: KASAN: slab-use-after-free in queue_work_on+0x25/0x70\n  Write of size 8 at addr ff11000000c3bd00 by task repro/55\n\nHold an RCU read lock across the add, like io_req_local_work_add() already\ndoes, and have io_ring_exit_work() wait for a grace period for SQPOLL rings\nas well before freeing the ctx.","cvssScore":null,"cvssSeverity":null,"cvssVector":null,"cwes":[],"vendors":[],"products":[],"references":[{"url":"https://git.kernel.org/stable/c/395b25968fe854d4efaa19a8e9b7a5b6d1b3eea3","tags":[]},{"url":"https://git.kernel.org/stable/c/42b3332efacfd2140be4cd0dedad4fb96b8ae90e","tags":[]},{"url":"https://git.kernel.org/stable/c/891bd8335a0de3bb15c3b797ce3026bbb0dbef6c","tags":[]},{"url":"https://git.kernel.org/stable/c/a92193c91e8839fe5fc209616ea95465ae4b919d","tags":[]}],"exploitRefs":[],"hasPoc":false,"ai":null}