CVE-2021-47040: io_uring: fix overflows checks in provide buffers
In the Linux kernel, the following vulnerability has been resolved:
iouring: fix overflows checks in provide buffers
Colin reported before possible overflow and sign extension problems in ioprovidebuffersprep(). As Linus pointed out previous attempt did nothing useful, see d81269fecb8ce ("iouring: fix providebuffers sign extension").
Do that with help of check<op>overflow helpers. And fix struct ioprovidebuf::len type, as it doesn't make much sense to keep it signed.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
Linux kernel io_uring provide buffers overflow checksto a version that resolves this vulnerability.Patch d81269fecb8ce
Event History
Frequently Asked Questions
What is the severity of CVE-2021-47040?
CVE-2021-47040 has been classified as a vulnerability with a medium severity level.
How do I fix CVE-2021-47040?
To address CVE-2021-47040, it is recommended to update the Linux kernel to versions 5.10.38, 5.11.22, or 5.12.5 or later.
What software versions are affected by CVE-2021-47040?
CVE-2021-47040 impacts Linux kernel versions between 5.8 and 5.10.37, 5.11 and 5.11.21, and 5.12 and 5.12.4.
What kind of issues does CVE-2021-47040 address?
CVE-2021-47040 addresses overflow and sign extension problems in the io_provide_buffers_prep() function of the Linux kernel.
Who reported the issues related to CVE-2021-47040?
The vulnerability CVE-2021-47040 was reported by a user named Colin.