CVE-2021-47566 Information

Description

In the Linux kernel the following vulnerability has been resolved:

proc/vmcore: fix clearing user buffer by properly using clear_user()

To clear a user buffer we cannot simply use memset we have to use clear_user(). With a virtio-mem device that registers a vmcore_cb and has some logically unplugged memory inside an added Linux memory block I can easily trigger a BUG by copying the vmcore via ## Reference https://git.kernel.org/stable/c/a9e164bd160be8cbee1df70acb379129e3cd2e7c https://git.kernel.org/stable/c/33a7d698f30fa0b99d50569e9909d3baa65d8f6a https://git.kernel.org/stable/c/99d348b82bcb36171f24411d3f1a15706a2a937a https://git.kernel.org/stable/c/9ef384ed300d1bcfb23d0ab0b487d544444d4b52 https://git.kernel.org/stable/c/fd7974c547abfb03072a4ee706d3a6f182266f89 https://git.kernel.org/stable/c/a8a917058faf4abaec9fb614bb6d5f8fe3529ec6 https://git.kernel.org/stable/c/7b3a34f08d11e7f05cd00b8e09adaa15192f0ad1 https://git.kernel.org/stable/c/c1e63117711977cc4295b2ce73de29dd17066c82