CVE-2022-49425 Information

Description

In the Linux kernel the following vulnerability has been resolved:

f2fs: fix dereference of stale list iterator after loop body

The list iterator variable will be a bogus pointer if no break was hit. Dereferencing it (cur->page in this case) could load an out-of-bounds/undefined value making it unsafe to use that in the comparision to determine if the specific element was found.

Since ‘cur->page’ can be out-ouf-bounds it cannot be guaranteed that by chance (or intention of an attacker) it matches the value of ‘page’ even though the correct element was not found.

This is fixed by using a separate list iterator variable for the loop and only setting the original variable if a suitable element was found. Then determing if the element was found is simply checking if the variable is set.

Reference

https://git.kernel.org/stable/c/2aaf51dd39afb6d01d13f1e6fe20b684733b37d5 https://git.kernel.org/stable/c/385edd3ce5b4b1e9d31f474a5e35a39779ec1110 https://git.kernel.org/stable/c/45b2b7d7108ae1e25a5036cab04ab9273e792332 https://git.kernel.org/stable/c/51d584704d18e60fa473823654f35611c777b291 https://git.kernel.org/stable/c/5e47a7add3dda7f236548c5ec3017776dc2a729f https://git.kernel.org/stable/c/b26e1c777890e4b938136deb8ec07a29f33862e4 https://git.kernel.org/stable/c/ed7efc472c00986dcd6903ab6ed165c7fa167674