UBUNTU-CVE-2024-47736

Advisory lineage Upstream: 1 Downstream: 12
Upstream
CVE-2024-47736
Published: 21 Oct 2024, 13:15
Last modified:03 Jun 2026, 13:38

Vulnerability Summary

Overall Risk (default)
low
22/100
CVSS Score
5.5 MEDIUM
3.1 (osv_ubuntu)
EPSS Score
No data
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

21 Oct 2024, 13:15
Published
Vulnerability first disclosed
03 Jun 2026, 13:38
Last Modified
Vulnerability information updated

Description

In the Linux kernel, the following vulnerability has been resolved: erofs: handle overlapped pclusters out of crafted images properly syzbot reported a task hang issue due to a deadlock case where it is waiting for the folio lock of a cached folio that will be used for cache I/Os. After looking into the crafted fuzzed image, I found it's formed with several overlapped big pclusters as below: Ext: logical offset | length : physical offset | length 0: 0.. 16384 | 16384 : 151552.. 167936 | 16384 1: 16384.. 32768 | 16384 : 155648.. 172032 | 16384 2: 32768.. 49152 | 16384 : 537223168.. 537239552 | 16384 ... Here, extent 0/1 are physically overlapped although it's entirely _impossible_ for normal filesystem images generated by mkfs. First, managed folios containing compressed data will be marked as up-to-date and then unlocked immediately (unlike in-place folios) when compressed I/Os are complete. If physical blocks are not submitted in the incremental order, there should be separate BIOs to avoid dependency issues. However, the current code mis-arranges z_erofs_fill_bio_vec() and BIO submission which causes unexpected BIO waits. Second, managed folios will be connected to their own pclusters for efficient inter-queries. However, this is somewhat hard to implement easily if overlapped big pclusters exist. Again, these only appear in fuzzed images so let's simply fall back to temporary short-lived pages for correctness. Additionally, it justifies that referenced managed folios cannot be truncated for now and reverts part of commit 2080ca1ed3e4 ("erofs: tidy up `struct z_erofs_bvec`") for simplicity although it shouldn't be any difference.

CVSS Metrics

  • v3.1•MEDIUM•Score: 5.5CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected Systems

  • ubuntu•linux

    all | < 6.8.0-60.63

  • ubuntu•linux-allwinner-5.19

    all

  • ubuntu•linux-aws

    all | < 6.8.0-1029.31

  • ubuntu•linux-aws-5.0

    all

  • ubuntu•linux-aws-5.11

    all

  • ubuntu•linux-aws-5.13

    all

  • ubuntu•linux-aws-5.15

    all

  • ubuntu•linux-aws-5.19

    all

  • ubuntu•linux-aws-5.3

    all

  • ubuntu•linux-aws-5.8

    all

  • ubuntu•linux-aws-6.2

    all

  • ubuntu•linux-aws-6.5

    all

  • ubuntu•linux-aws-6.8

    < 6.8.0-1029.31~22.04.1

  • ubuntu•linux-aws-fips

    all

  • ubuntu•linux-azure

    all | all | < 6.8.0-1029.34

  • ubuntu•linux-azure-5.11

    all

  • ubuntu•linux-azure-5.13

    all

  • ubuntu•linux-azure-5.15

    all

  • ubuntu•linux-azure-5.19

    all

  • ubuntu•linux-azure-5.3

    all

  • ubuntu•linux-azure-5.8

    all

  • ubuntu•linux-azure-6.11

    < 6.11.0-1012.12~24.04.1

  • ubuntu•linux-azure-6.2

    all

  • ubuntu•linux-azure-6.5

    all

  • ubuntu•linux-azure-6.8

    < 6.8.0-1029.34~22.04.1

  • ubuntu•linux-azure-edge

    all

  • ubuntu•linux-azure-fde

    all | all

  • ubuntu•linux-azure-fde-5.19

    all

  • ubuntu•linux-azure-fde-6.2

    all

  • ubuntu•linux-azure-fips

    all

  • ubuntu•linux-azure-nvidia

    < 6.8.0-1016.17

  • ubuntu•linux-bluefield

    all | all

  • ubuntu•linux-fips

    all | < 6.8.0-78.78+fips1

  • ubuntu•linux-gcp

    all | all | < 6.8.0-1030.32

  • ubuntu•linux-gcp-5.11

    all

  • ubuntu•linux-gcp-5.13

    all

  • ubuntu•linux-gcp-5.15

    all

  • ubuntu•linux-gcp-5.19

    all

  • ubuntu•linux-gcp-5.3

    all

  • ubuntu•linux-gcp-5.8

    all

  • ubuntu•linux-gcp-6.11

    < 6.11.0-1011.11~24.04.1

  • ubuntu•linux-gcp-6.2

    all

  • ubuntu•linux-gcp-6.5

    all

  • ubuntu•linux-gcp-6.8

    < 6.8.0-1030.32~22.04.1

  • ubuntu•linux-gcp-fips

    all

  • ubuntu•linux-gke

    all | all | < 6.8.0-1025.29

  • ubuntu•linux-gke-4.15

    all

  • ubuntu•linux-gke-5.15

    all

  • ubuntu•linux-gke-5.4

    all

  • ubuntu•linux-gkeop

    all | < 6.8.0-1012.14

Showing first 50 affected entries in server-rendered view.

References (20)