RDMA/mlx5: Fix undefined shift of user RQ WQE size

Summary

In the Linux kernel, the following vulnerability has been resolved: RDMA/mlx5: Fix undefined shift of user RQ WQE size set_rq_size() computes the RQ WQE size as "1 << rq_wqe_shift" based on the user-provided rq_wqe_shift, which is only checked to be greater than 32, so shifts of 32 are still accepted. A shift of 31 also overflows a signed integer, leading to undefined behavior. Use check_shl_overflow() to compute the RQ WQE size and reject any invalid values.

Timeline

1. Aug 15, 2026, 5:58 AM UTCCVE published
2. Oct 16, 2026, 6:52 PM UTCCISA SSVC assessment

   Exploitation: none · Automatable: no · Technical impact: total

3. Oct 16, 2026, 6:55 PM UTCRecord last updated

Affected versions

• Linux Linux

  From e126ba97dba9edeb6fafa3665b5f8497fc9cdf8c · fixed in 9fff54929cc00849d738faa99f06c32399aeb026; From e126ba97dba9edeb6fafa3665b5f8497fc9cdf8c · fixed in b746f949c2ac2b041102836095d6d4a2ef21fa75; From e126ba97dba9edeb6fafa3665b5f8497fc9cdf8c · fixed in c1dbf52d24a8cb1aa56780ba51b72e7d495f258c; From e126ba97dba9edeb6fafa3665b5f8497fc9cdf8c · fixed in 6fc874fdfb366bfb11c62e6af9a831c8be59ddda; From e126ba97dba9edeb6fafa3665b5f8497fc9cdf8c · fixed in 42f3d2c8c18b92ea33e506a38b64f1a8986c2823; From e126ba97dba9edeb6fafa3665b5f8497fc9cdf8c · fixed in 4b87a2497276a72fd63028e7419abf0fb7ed837b; From e126ba97dba9edeb6fafa3665b5f8497fc9cdf8c · fixed in b732db02a2b04cde393638df19de6251ce62a74e; From e126ba97dba9edeb6fafa3665b5f8497fc9cdf8c · fixed in d881d60223aac8fdc12b227d89c76e131e92a9cd

• Linux Linux

  3.11

• KernelLinux

  From 3.11.0 · fixed in 5.10.261; From 5.11.0 · fixed in 5.15.212; From 5.16.0 · fixed in 6.1.178; From 6.2.0 · fixed in 6.6.145; From 6.7.0 · fixed in 6.12.97; From 6.13.0 · fixed in 6.18.40; From 6.19.0 · fixed in 7.1.5

References 8