Medium · published April 10, 2024
In the Linux kernel, the following vulnerability has been resolved:
x86, relocs: Ignore relocations in .notes section
When building with CONFIG_XEN_PV=y, .text symbols are emitted into
the .notes section so that Xen can find the "startup_xen" entry point.
This information is used prior to booting the kernel, so relocations
are not useful. In fact, performing relocations against the .notes
section means that the KASLR base is exposed since /sys/kernel/notes
is world-readable.
To avoid leaking the KASLR base without breaking unprivileged tools that
are expecting to read /sys/kernel/notes, skip performing relocations in
the .notes section. The values readable in .notes are then identical to
those found in System.map.
| Product | Versions | Fixed in |
|---|---|---|
| linux/linux_kernel | ≥ 2.6.23, < 4.19.311 | 4.19.311 |
| linux/linux_kernel | ≥ 4.20, < 5.4.273 | 5.4.273 |
| linux/linux_kernel | ≥ 5.5, < 5.10.214 | 5.10.214 |
| linux/linux_kernel | ≥ 5.11, < 5.15.153 | 5.15.153 |
| linux/linux_kernel | ≥ 5.16, < 6.1.83 | 6.1.83 |
| linux/linux_kernel | ≥ 6.2, < 6.6.23 | 6.6.23 |
| linux/linux_kernel | ≥ 6.7, < 6.7.11 | 6.7.11 |
| linux/linux_kernel | ≥ 6.8, < 6.8.2 | 6.8.2 |
| linux/linux_kernel | ≥ 6.8.3, ≤ 6.8.12 | — |
| debian/debian_linux | all versions | — |