In the Linux kernel, the following vulnerability has been resolved:

bcache: revert replacing IS_ERR_OR_NULL with IS_ERR again

Commit 028ddcac477b ("bcache: Remove unnecessary NULL point check in
node allocations") leads a NULL pointer deference in cache_set_flush().

1721         if (!IS_ERR_OR_NULL(c->root))
1722                 list_add(&c->root->list, &c->btree_cache);

>From the above code in cache_set_flush(), if previous registration code
fails before allocating c->root, it is possible c->root is NULL as what
it is initialized. __bch_btree_node_alloc() never returns NULL but
c->root is possible to be NULL at above line 1721.

This patch replaces IS_ERR() by IS_ERR_OR_NULL() to fix this.

https://git.kernel.org/stable/c/336e30f32ae7c043fde0f6fa21586ff30bea9fe2

https://git.kernel.org/stable/c/4379c5828492a4c2a651c8f826a01453bd2b80b0

https://git.kernel.org/stable/c/5202391970ffbf81975251b3526b890ba027b715

https://git.kernel.org/stable/c/5e0e913624bcd24f3de414475018d3023f060ee1

https://git.kernel.org/stable/c/b2e382ae12a63560fca35050498e19e760adf8c0

https://git.kernel.org/stable/c/cc05aa2c0117e20fa25a3c0d915f98b8f2e78667

https://git.kernel.org/stable/c/fb5fee35bdd18316a84b5f30881a24e1415e1464