CVE-2025-39736

In the Linux kernel, the following vulnerability has been resolved: mm/kmemleak: avoid deadlock by moving pr_warn() outside kmemleak_lock When netpoll is enabled, calling pr_warn_once() while holding kmemleak_lock in mem_pool_alloc() can cause a deadlock due to lock inversion with the netconsole subsystem. This occurs because pr_warn_once() may trigger netpoll, which eventually leads to __alloc_skb() and back into kmemleak code, attempting to reacquire kmemleak_lock. This is the path for the deadlock. mem_pool_alloc() -> raw_spin_lock_irqsave(&kmemleak_lock, flags); -> pr_warn_once() -> netconsole subsystem -> netpoll -> __alloc_skb -> __create_object -> raw_spin_lock_irqsave(&kmemleak_lock, flags); Fix this by setting a flag and issuing the pr_warn_once() after kmemleak_lock is released.

• linux linux kernel (>= 5.4 < 5.4.297) • linux linux kernel (>= 5.5 < 5.10.241) • linux linux kernel (>= 5.11 < 5.15.190) • linux linux kernel (>= 5.16 < 6.1.149) • linux linux kernel (>= 6.2 < 6.6.103) • linux linux kernel (>= 6.7 < 6.12.43) • linux linux kernel (>= 6.13 < 6.15.11) • linux linux kernel (>= 6.16 < 6.16.2) • linux linux kernel 6.17 • debian debian linux 11.0