In the Linux kernel, the following vulnerability has been resolved: dpll: fix xa_alloc_cyclic() error handling In case of returning 1 from xa_alloc_cyclic() (wrapping) ERR_PTR(1) will be returned, which will cause IS_ERR() to be false. Which can lead to dereference not allocated pointer (pin). Fix it by checking if err is lower than zero. This wasn't found in real usecase, only noticed. Credit to Pierre.