CVE-2022-49709

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> cfi: Fix __cfi_slowpath_diag RCU usage with cpuidle<br /> <br /> RCU_NONIDLE usage during __cfi_slowpath_diag can result in an invalid<br /> RCU state in the cpuidle code path:<br /> <br /> WARNING: CPU: 1 PID: 0 at kernel/rcu/tree.c:613 rcu_eqs_enter+0xe4/0x138<br /> ...<br /> Call trace:<br /> rcu_eqs_enter+0xe4/0x138<br /> rcu_idle_enter+0xa8/0x100<br /> cpuidle_enter_state+0x154/0x3a8<br /> cpuidle_enter+0x3c/0x58<br /> do_idle.llvm.6590768638138871020+0x1f4/0x2ec<br /> cpu_startup_entry+0x28/0x2c<br /> secondary_start_kernel+0x1b8/0x220<br /> __secondary_switched+0x94/0x98<br /> <br /> Instead, call rcu_irq_enter/exit to wake up RCU only when needed and<br /> disable interrupts for the entire CFI shadow/module check when we do.