CVE-2026-46181

In the Linux kernel, the following vulnerability has been resolved:

RDMA/mlx4: Fix mis-use of RCU in mlx4_srq_event()

Sashiko points out the radix_tree itself is RCU safe, but nothing ever

frees the mlx4_srq struct with RCU, and it isn't even accessed within the

RCU critical section. It also will crash if an event is delivered before

the srq object is finished initializing.

Use the spinlock since it isn't easy to make RCU work, use

refcount_inc_not_zero() to protect against partially initialized objects,

and order the refcount_set() to be after the srq is fully initialized.