CVE-2021-47153: i2c: i801: Don't generate an interrupt on bus reset
In the Linux kernel, the following vulnerability has been resolved:
i2c: i801: Don't generate an interrupt on bus reset
Now that the i2c-i801 driver supports interrupts, setting the KILL bit in a attempt to recover from a timed out transaction triggers an interrupt. Unfortunately, the interrupt handler (i801isr) is not prepared for this situation and will try to process the interrupt as if it was signaling the end of a successful transaction. In the case of a block transaction, this can result in an out-of-range memory access.
This condition was reproduced several times by syzbot: https://syzkaller.appspot.com/bug?extid=ed71512d469895b5b34e https://syzkaller.appspot.com/bug?extid=8c8dedc0ba9e03f6c79e https://syzkaller.appspot.com/bug?extid=c8ff0b6d6c73d81b610e https://syzkaller.appspot.com/bug?extid=33f6c360821c399d69eb https://syzkaller.appspot.com/bug?extid=be15dc0b1933f04b043a https://syzkaller.appspot.com/bug?extid=b4d3fd1dfd53e90afd79
So disable interrupts while trying to reset the bus. Interrupts will be enabled again for the following transaction.
Other sources
In the Linux kernel, the following vulnerability has been resolved:
i2c: i801: Don't generate an interrupt on bus reset
The Linux kernel CVE team has assigned CVE-2021-47153 to this issue.
Upstream advisory: https://lore.kernel.org/linux-cve-announce/2024032501-CVE-2021-47153-8c75@gregkh/T
— Red Hat
Linux Kernel could allow a local authenticated attacker to obtain sensitive information, caused by an out-of-bounds read flaw in the interrupt handler (i801isr). By sending a specially crafted request, an attacker could exploit this vulnerability to obtain sensitive information or cause a denial of service condition.
— IBM
Affected Software
Remediation
Event History
Frequently Asked Questions
What is the severity of CVE-2021-47153?
CVE-2021-47153 has a moderate severity due to the risk of interrupt generation on bus reset, potentially leading to system instability.
How do I fix CVE-2021-47153?
To fix CVE-2021-47153, upgrade the Linux kernel to one of the patched versions, such as 4.4.271, 4.9.271, 4.14.235, 4.19.193, 5.4.124, 5.10.42, 5.12.9, or 5.13.
Which versions of the Linux kernel are affected by CVE-2021-47153?
Affected versions include all Linux kernel versions prior to 4.4.271, 4.9.271, 4.14.235, 4.19.193, 5.4.124, 5.10.42, 5.12.9, and 5.13.
Is CVE-2021-47153 specific to certain Linux distributions?
Yes, CVE-2021-47153 primarily affects Red Hat-based distributions due to the vulnerability in the i2c-i801 driver.
What could happen if CVE-2021-47153 is exploited?
Exploitation of CVE-2021-47153 could result in unpredictable system behavior and potential crashes due to improper interrupt handling.