CVE-2026-90435
Published: September 19, 2026Last modified: October 6, 2026
Description
In the Linux kernel, the following vulnerability has been resolved: RDMA/mlx5: Fix integer overflow of user QP buffer size set_user_buf_size() computes the QP buffer size by left-shifting the user-supplied rq.wqe_cnt and rq.wqe_shift values as signed integers. A sufficiently large rq.wqe_cnt causes signed integer overflow, which is undefined behavior, and yields a small or negative buf_size, causing ib_umem_get() to map a buffer smaller than the hardware will actually write into. Replace the shifts and addition with check_shl_overflow() and check_add_overflow(), rejecting invalid user inputs. Moreover, guard the identical shift computing qp->sq.offset in _create_user_qp() before set_user_buf_size() is reached.
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 7.8 |
| Attack Vector | LOCAL |
| Attack complexity | LOW |
| Privileges required | LOW |
| User interaction | NONE |
| Scope | UNCHANGED |
| Confidentiality | HIGH |
| Integrity impact | HIGH |
| Availability impact | HIGH |
| Vector | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
Status
| Product | Release | Package | Status |
|---|---|---|---|
| Alpaquita Linux | 23 LTS | linux-lts | Fixed (6.1.189-r0) |
| 25 LTS | linux-lts | Fixed (6.12.111-r0) | |
| Stream | linux-lts | Fixed (6.18.53-r0) |
References
- https://git.kernel.org/stable/c/42fb8aefffff5b458aaa66803364a16e0ea44129
- https://git.kernel.org/stable/c/5b6cfc6d7ff0959dd9766fdc24286a253b59ca77
- https://git.kernel.org/stable/c/c845e5e05140ea1bc64a5b1107942d93c876034d
- https://git.kernel.org/stable/c/ccce6b7ef1d7efc59ccba3421e1339c6e63a3d20
- https://git.kernel.org/stable/c/d7fa2ff72ad1861eac194a4e0075d504ba8c246e
- https://git.kernel.org/stable/c/d99622e40aaa910ade681dfd4dc0fa240a011331
- https://git.kernel.org/stable/c/dec47e4b0fe34afdf38caa72b4408ba95502e5de
- https://git.kernel.org/stable/c/f917707f0de0832b8ab582391b1f64e549995c6c