A time-of-check to time-of-use issue exists in io_uring subsystem's IORING_OP_CLOSE operation in the Linux kernel's versions 5.6 - 5.11 (inclusive), which allows a local user to elevate their privileges to root. Introduced in b5dba59e0cf7e2cc4d3b3b1ac5fe81ddf21959eb, patched in 9eac1904d3364254d622bf2c771c4f85cd435fc2, backported to stable in 788d0824269bef539fe31a785b1517882eafed93.
https://security.netapp.com/advisory/ntap-20230731-0006/
https://kernel.dance/9eac1904d3364254d622bf2c771c4f85cd435fc2
https://kernel.dance/788d0824269bef539fe31a785b1517882eafed93