Overlayfs in the Linux kernel and shiftfs, a non-upstream patch to the Linux kernel included in the Ubuntu 5.0 and 5.3 kernel series, both replace vma->vm_file in their mmap handlers. On error the original value is not restored, and the reference is put for the file to which vm_file points. On upstream kernels this is not an issue, as no callers dereference vm_file following after call_mmap() returns an error. However, the aufs patchs change mmap_region() to replace the fput() using a local variable with vma_fput(), which will fput() vm_file, leading to a refcount underflow.
Metrics
Affected Vendors & Products
Advisories
| Source | ID | Title |
|---|---|---|
EUVD |
EUVD-2019-6717 | Overlayfs in the Linux kernel and shiftfs, a non-upstream patch to the Linux kernel included in the Ubuntu 5.0 and 5.3 kernel series, both replace vma->vm_file in their mmap handlers. On error the original value is not restored, and the reference is put for the file to which vm_file points. On upstream kernels this is not an issue, as no callers dereference vm_file following after call_mmap() returns an error. However, the aufs patchs change mmap_region() to replace the fput() using a local variable with vma_fput(), which will fput() vm_file, leading to a refcount underflow. |
Ubuntu USN |
USN-4208-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-4209-1 | Linux kernel vulnerabilities |
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
Thu, 20 Mar 2025 05:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Redhat
Redhat enterprise Linux |
|
| CPEs | cpe:/o:redhat:enterprise_linux:8 | |
| Vendors & Products |
Redhat
Redhat enterprise Linux |
Status: PUBLISHED
Assigner: canonical
Published:
Updated: 2024-09-16T19:52:18.313Z
Reserved: 2019-08-29T00:00:00
Link: CVE-2019-15794
No data.
Status : Modified
Published: 2020-04-24T00:15:11.933
Modified: 2024-11-21T04:29:28.880
Link: CVE-2019-15794
OpenCVE Enrichment
No data.
EUVD
Ubuntu USN