CVE Catalog

CVE-2026-80985

HighCVSS 8.2
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.52%

43th percentile - higher than 43% of all known CVEs

Summary

In the Linux kernel, the net/smc module's smc_llc_rmt_delete_rkey() and smc_llc_save_add_link_rkeys() read the part of a v2 message that does not fit into the 44-byte smc_llc_msg union, bounding themselves by the buffer size rather than what arrived. On a link with a shared v2 receive buffer, a 44-byte DELETE_RKEY_V2 declaring 255 rkeys reaches rkey[9..254] in leftover data and passes them to smc_rtoken_delete(), potentially deleting a registered rtoken. The fix copies the tail into the queue entry and declares inline rkeys as a union member.

Risk Assessment

It is possible to delete or install invalid rtoken keys on an SMC-Rv2 link, potentially leading to data corruption, communication errors, or compromise of connection integrity.

Recommendation

Update the Linux kernel to a version containing the fix. Monitor SMC-Rv2 connections for communication errors and unexpected disconnections.

Other vulnerabilities in Linux kernel

See all
Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: net/smc: carry oversized SMC-Rv2 LLC messages in the queue entry smc_llc_rmt_delete_rkey() and smc_llc_save_add_link_rkeys() read the part of a v2 message that does not fit into the 44-byte union smc_llc_msg, and both bound themselves by the size of the buffer it landed in, not by what arrived. On a link with a shared v2 receive buffer a 44-byte DELETE_RKEY_V2 declaring 255 rkeys reaches rkey[9..254] in whatever an earlier message left in lgr->wr_rx_buf_v2, and passes each of them to smc_rtoken_delete(). One of those 255 matched a registered rtoken and deleted it. An ADD_LINK on such a link installs up to 255 rtokens from the same bytes. Copy the tail into the queue entry, so its length is the length of the message that arrived, and declare the rkeys that fit inline as a member of the union instead of reaching them through a cast. The same DELETE_RKEY_V2 now processes the 9 rkeys it carries. The copy is limited to the longest tail the two functions can read, so the peer does not pick the size of the entry. The bound the previous patch placed on links without a shared v2 receive buffer is no longer needed.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS