CVE-2026-23220

In the Linux kernel, the following vulnerability has been resolved:

ksmbd: fix infinite loop caused by nextsmb2rcvhdroff reset in error paths

The problem occurs when a signed request fails smb2 signature verification check. In __processrequest(), if checksignreq() returns an error, setsmb2rspstatus(work, STATUSACCESSDENIED) is called. setsmb2rspstatus() set work->nextsmb2rcvhdroff as zero. By resetting nextsmb2rcvhdroff to zero, the pointer to the next command in the chain is lost. Consequently, ischainedsmb2message() continues to point to the same request header instead of advancing. If the header's NextCommand field is non-zero, the function returns true, causing __handleksmbdwork() to repeatedly process the same failed request in an infinite loop. This results in the kernel log being flooded with "bad smb2 signature" messages and high CPU usage.

This patch fixes the issue by changing the return value from SERVERHANDLERCONTINUE to SERVERHANDLERABORT. This ensures that the processing loop terminates immediately rather than attempting to continue from an invalidated offset.