CVE-2024-48881 bcache: revert replacing IS_ERR_OR_NULL with IS_ERR again
A NULL pointer dereference in the Linux kernel bcache module can cause a system crash during cache set flushing.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2024-48881?
CVE-2024-48881 is a medium-severity vulnerability in Linux kernel, published on 11 Jan 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
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.
Weakness: CWE-476
Which versions are affected by CVE-2024-48881?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2024-48881?
Apply the vendor's patch.
Is CVE-2024-48881 being exploited?
There is no known exploitation of CVE-2024-48881 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-56139, AZL-56157, BELL-CVE-2024-48881, DEBIAN-CVE-2024-48881, GHSA-2g99-pch7-3284, UBUNTU-CVE-2024-48881.