In the Linux kernel, the following vulnerability has been resolved:
ext4: always panic when errors=panic is specified
Before commit 014c9caa29d3 (ext4: make ext4_abort() use __ext4_error()), the following series of commands would trigger a panic:
After commit 014c9caa29d3, remounting a file system using the test mount option abort will no longer trigger a panic. This commit will restore the behaviour immediately before commit 014c9caa29d3. (However, note that the Linux kernels behavior has not been consistent; some previous kernel versions, including 5.4 and 4.19 similarly did not panic after using the mount option abort.)
This also makes a change to long-standing behaviour; namely, the following series commands will now cause a panic, when previously it did not:
However, this makes ext4s behaviour much more consistent, so this is a good thing.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Linux_kernel | Linux | 5.11.0 (including) | 5.11.20 (excluding) |
| Linux_kernel | Linux | 5.12.0 (including) | 5.12.3 (excluding) |