Linux Kernel RCU Misuse in mlx4 SRQ Event Handling
CVE-2026-46181 Published on May 28, 2026
RDMA/mlx4: Fix mis-use of RCU in mlx4_srq_event()
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.
Products Associated with CVE-2026-46181
Want to know whenever a new CVE is published for Linux Kernel? stack.watch will email you.
Affected Versions
Linux:- Version 30353bfc43a1602c020f31d95cf27182ffd23824 and below 1e2a44875b6afb4add1115f7f3351dcbeb6f273d is affected.
- Version 30353bfc43a1602c020f31d95cf27182ffd23824 and below 8b7833f3bce35cb0d01c1503781523c099c675f0 is affected.
- Version 30353bfc43a1602c020f31d95cf27182ffd23824 and below c9341307ea16b9395c2e4c9c94d8499d91fe31d0 is affected.
- Version 4.9 is affected.
- Before 4.9 is unaffected.
- Version 6.18.30, <= 6.18.* is unaffected.
- Version 7.0.7, <= 7.0.* is unaffected.
- Version 7.1-rc3, <= * is unaffected.