Description
In the Linux kernel, the following vulnerability has been resolved:
ext4: don't enable large folios on encrypted inodes
Commit 709f0f1f1bf5 ("ext4: add checks for large folio
incompatibilities when BS > PS") disables large folios at mount time
if the "encrypt" feature is set. However, enabling that feature on a
mounted filesystem circumvents that check, and writing encrypted data
results in a crash:
BUG: kernel NULL pointer dereference, address: 0000000000000028
Workqueue: ext4-rsv-conversion ext4_end_io_rsv_work
RIP: 0010:ext4_finish_bio+0xf7/0x3e0
Call Trace:
ext4_release_io_end+0x51/0x110
ext4_end_io_end+0x4c/0xe0
ext4_end_io_rsv_work+0xb3/0x100
Fix this by disabling large folios on encrypted inodes, as is
already done for inodes that use data journaling.
This affects all kernels between v6.19 and v7.2, but it is not needed
in v7.3, where the code was significantly refactored.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Linux | Linux | 6.19 | 7.2.10 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | linux | 7.2.10-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | linux +8 | No fix yet | — |
| Ubuntu 26.04 LTS | linux +14 | No fix yet | — |
| Ubuntu 24.04 LTS | linux-riscv +33 | No fix yet | — |
| Ubuntu 22.04 LTS | linux-riscv +32 | No fix yet | — |
| Ubuntu 20.04 LTS | linux-gke +28 | No fix yet | — |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 18.04 LTS | linux-gcp +14 | No fix yet | — |
| Ubuntu 16.04 LTS | linux-hwe-edge | No fix yet | — |
| Ubuntu Pro Realtime 24.04 LTS | linux-realtime-6.14 +1 | No fix yet | — |
Advisories 1
- WID-SEC-2026-4152 Linux Kernel: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 12, 2026