vt: prevent kernel-infoleak in con_font_get()

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: vt: prevent kernel-infoleak in con_font_get() font.data may not initialize all memory spaces depending on the implementation of vc->vc_sw->con_font_get. This may cause info-leak, so to prevent this, it is safest to modify it to initialize the allocated memory space to 0, and it generally does not affect the overall performance of the system.

References

• https://git.kernel.org/stable/c/efc67cee700b89ffbdb74a0603a083ec1290ae31
• https://git.kernel.org/stable/c/dc794e878e6d79f75205be456b1042a289c5759d
• https://git.kernel.org/stable/c/1e5a17dc77d8a8bbe67040b32e2ef755901aba44
• https://git.kernel.org/stable/c/b3959d5eca136e0588f9af3867b34032160cb826
• https://git.kernel.org/stable/c/23c4cb8a56978e5b1baa171d42e616e316c2039d
• https://git.kernel.org/stable/c/dc2d5f02636c7587bdd6d1f60fc59c55860b00a4
• https://git.kernel.org/stable/c/adb1f312f38f0d2c928ceaff089262798cc260b4
• https://git.kernel.org/stable/c/f956052e00de211b5c9ebaa1958366c23f82ee9e