CVE-2026-74749

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> rseq: Prevent hard lockup on granted time slice extension<br /> <br /> __exit_to_user_mode_loop() invokes rseq_grant_timeslice_extension() with<br /> interrupts enabled. If the extension is granted it invokes<br /> hrtimer_rearm_deferred_tif() to ensure that a pending deferred hrtimer<br /> rearm is handled before exiting to user space.<br /> <br /> Though this invokes __hrtimer_rearm_deferred() which expects to be invoked<br /> with interrupts disabled as it takes hrtimer_cpu_base::lock with<br /> raw_spin_lock(). That&amp;#39;s a livelock waiting to happen and caught by lockdep:<br /> <br /> WARNING: ./include/linux/hrtimer_rearm.h:17 at irqentry_exit, CPU#1: slice_test<br /> WARNING: inconsistent lock state<br /> inconsistent {IN-HARDIRQ-W} -&gt; {HARDIRQ-ON-W} usage.<br /> <br /> Prevent this by disabling interrupts around the invocation of<br /> hrtimer_rearm_deferred_tif() in rseq_grant_timeslice_extension().<br /> <br /> [ tglx: Massaged change log ]