Description
In the Linux kernel, the following vulnerability has been resolved: RDMA/rtrs-srv: Fix integer underflow in process_read and process_write usr_len is read from a network-supplied message field (le16_to_cpu) and used to compute data_len = off - usr_len without validating that usr_len <= off. A malicious RDMA client can send usr_len > off causing an integer underflow, resulting in data_len wrapping to a huge size_t value which is then passed to the rdma_ev callback as a memory length, leading to out-of-bounds memory access. Fix by reading and validating usr_len <= off before rtrs_srv_get_ops_ids() in both process_read() and process_write(), ensuring the early return path acquires no reference and has no resource leak.
References6
- git.kernel.org/stable/c/24ad03bfeda05fca04c56677e57fd3d6bc3e9978
- git.kernel.org/stable/c/2c52b2afded988233cd4ccc185cf5147bbc77a76
- git.kernel.org/stable/c/54bf38b27afc08a0eb6b732f9c14eb8a4bcb66b5
- git.kernel.org/stable/c/6b1e26e70d7ca9f0906af2283558a530eeb1f066
- git.kernel.org/stable/c/b042b4947752df0b3d16e683ac09fb4f7f0e33e0
- git.kernel.org/stable/c/c76e9123ab91a903396d26e6ab1b5caae5c6b149
Metrics
- CVSS 3.1
-
9.8
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 1% percentile: 43 · as of 9 November 2026
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