CVE-2026-72006

Summary

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

net/mlx5: free mlx5_st_idx_data on final dealloc

Workloads that repeatedly allocate and release mkeys carrying TPH steering-tag hints (e.g. churning RDMA MRs) leak one struct mlx5_st_idx_data per cycle; kmemleak flags it as unreferenced and the kmalloc slab grows over time.

When the last reference to an ST table entry is dropped, mlx5_st_dealloc_index() removed the entry from idx_xa but the backing mlx5_st_idx_data allocation was never freed.

Free idx_data after the xa_erase() so the lifetime of the bookkeeping struct matches the lifetime of the ST entry it tracks.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux888a7776f4fb04c19bec70c737c61c2f383c6b1e < 262da8b6ea03d01ee7ed01ad309e4c89941f6b14affected
LinuxLinux888a7776f4fb04c19bec70c737c61c2f383c6b1e < 6eb4cf2fa8997f62c11e0006dc010a1fd89c5a75affected
LinuxLinux888a7776f4fb04c19bec70c737c61c2f383c6b1e < df6134b527a88b3e65ba6ae5073664af091d5fd2affected
LinuxLinux6.17affected
LinuxLinux0 < 6.17unaffected
LinuxLinux6.18.40 <= 6.18.*unaffected
LinuxLinux7.1.5 <= 7.1.*unaffected
LinuxLinux7.2-rc4 <= *unaffected

Weaknesses

References