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Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

CVE-2021-47040

High
7.8/10

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.

  • LOW
  • LOCAL
  • HIGH
  • UNCHANGED
  • NONE
  • LOW
  • HIGH
  • HIGH

CWE-120 - Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

The program copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow.

References

Advisory Timeline

  • Published