CVE-2021-47040

Summary

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

io_uring: fix overflows checks in provide buffers

Colin reported before possible overflow and sign extension problems in io_provide_buffers_prep(). As Linus pointed out previous attempt did nothing useful, see d81269fecb8ce ("io_uring: fix provide_buffers sign extension").

Do that with help of check_<op>_overflow helpers. And fix struct io_provide_buf::len type, as it doesn't make much sense to keep it signed.

Affected Software

VendorProductVersion RangeStatus
LinuxLinuxefe68c1ca8f49e8c06afd74b699411bfbb8ba1ff < cbbc13b115b8f18e0a714d89f87fbdc499acfe2daffected
LinuxLinuxefe68c1ca8f49e8c06afd74b699411bfbb8ba1ff < 51bf90901952aaac564bbdb36b2b503050c53dd9affected
LinuxLinuxefe68c1ca8f49e8c06afd74b699411bfbb8ba1ff < 84b8c266c4bfe9ed5128e13253c388deb74b1b03affected
LinuxLinuxefe68c1ca8f49e8c06afd74b699411bfbb8ba1ff < 38134ada0ceea3e848fe993263c0ff6207fd46e7affected
LinuxLinux5.8affected
LinuxLinux0 < 5.8unaffected
LinuxLinux5.10.37 <= 5.10.*unaffected
LinuxLinux5.11.21 <= 5.11.*unaffected
LinuxLinux5.12.4 <= 5.12.*unaffected
LinuxLinux5.13 <= *unaffected

Weaknesses

ADP Enrichment

CVE Program Container

Additional References

CISA ADP Vulnrichment

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

References