High severity · published Sep 11, 2026
CVE-2026-80985
net/smc: carry oversized SMC-Rv2 LLC messages in the queue entry
8.2
CVSS
0.5%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
Low
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 44% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LI
Linux · Linux
27ef6a9981fe74191849966a6d5e0400a4008ab8 before edf30d65e3ac52f886f7d87b1a7449742e79157d; 27ef6a9981fe74191849966a6d5e0400a4008ab8 before 0d6f80be8ac5886842640d6526abf3f9a215be75; 27ef6a9981fe74191849966a6d5e0400a4008ab8 before 8d3c1ab82c11d4fadebf817a825fd221b3e197ea; 6.14 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-80985
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-80985
git.kernel.org
https://git.kernel.org/stable/c/0d6f80be8ac5886842640d6526abf3f9a215be75
git.kernel.org
https://git.kernel.org/stable/c/8d3c1ab82c11d4fadebf817a825fd221b3e197ea
git.kernel.org
https://git.kernel.org/stable/c/edf30d65e3ac52f886f7d87b1a7449742e79157d
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