CVE-2022-50410

Summary

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

NFSD: Protect against send buffer overflow in NFSv2 READ

Since before the git era, NFSD has conserved the number of pages held by each nfsd thread by combining the RPC receive and send buffers into a single array of pages. This works because there are no cases where an operation needs a large RPC Call message and a large RPC Reply at the same time.

Once an RPC Call has been received, svc_process() updates svc_rqst::rq_res to describe the part of rq_pages that can be used for constructing the Reply. This means that the send buffer (rq_res) shrinks when the received RPC record containing the RPC Call is large.

A client can force this shrinkage on TCP by sending a correctly- formed RPC Call header contained in an RPC record that is excessively large. The full maximum payload size cannot be constructed in that case.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux4452435948424e5322c2a2fefbdc2cf3732cc45d < 2007867c5874134f2271eb276398208070049dd3affected
LinuxLinux4452435948424e5322c2a2fefbdc2cf3732cc45d < 2be9331ca6061bc6ea32247266f45b8b21030244affected
LinuxLinux4452435948424e5322c2a2fefbdc2cf3732cc45d < ea4c3eee0fd72fcedaa238556044825639cd3607affected
LinuxLinux4452435948424e5322c2a2fefbdc2cf3732cc45d < 1868332032eccbab8c1878a0d918193058c0a905affected
LinuxLinux4452435948424e5322c2a2fefbdc2cf3732cc45d < 401bc1f90874280a80b93f23be33a0e7e2d1f912affected
LinuxLinux2.6.19affected
LinuxLinux0 < 2.6.19unaffected
LinuxLinux5.10.220 <= 5.10.*unaffected
LinuxLinux5.15.75 <= 5.15.*unaffected
LinuxLinux5.19.17 <= 5.19.*unaffected
LinuxLinux6.0.3 <= 6.0.*unaffected
LinuxLinux6.1 <= *unaffected

Weaknesses

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: total

References