CVE-2021-47483

Name of the Vulnerable Software and Affected Versions: Linux kernel (affected versions not specified)

Description: The issue is related to a possible double-free in the regcache rbtree exit() function. When 'present' realloc fails in regcache rbtree insert to block(), the 'blk' assigned to 'rbnode->block' will be freed, causing 'rbnode->block' to point to freed memory. In the error handling path of regcache rbtree init(), 'rbnode->block' will be freed again in regcache rbtree exit(), resulting in a double-free error reported by KASAN. The error occurs in the following call trace: slab free freelist hook, kfree, regcache rbtree exit, regcache rbtree init, regcache init, regmap init, devm regmap init, madera spi probe, spi probe, and really probe. To fix this, the assignment of rbnode->block is moved to immediately after the reallocation has succeeded, ensuring the data structure remains valid even if the second reallocation fails.

Recommendations: At the moment, there is no information about a newer version that contains a fix for this vulnerability.