CVE-2021-47340 jfs: fix GPF in diFree
A null pointer dereference in the Linux kernel JFS filesystem allows local attackers to cause a system crash via a general protection fault.
- 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-2021-47340?
CVE-2021-47340 is a medium-severity vulnerability in Linux kernel, published on 21 May 2024. 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:
jfs: fix GPF in diFree
Avoid passing inode with JFS_SBI(inode->i_sb)->ipimap == NULL to diFree()[1]. GFP will appear:
struct inode *ipimap = JFS_SBI(ip->i_sb)->ipimap; struct inomap *imap = JFS_IP(ipimap)->i_imap;
JFS_IP() will return invalid pointer when ipimap == NULL
Call Trace: diFree+0x13d/0x2dc0 fs/jfs/jfs_imap.c:853 [1] jfs_evict_inode+0x2c9/0x370 fs/jfs/inode.c:154 evict+0x2ed/0x750 fs/inode.c:578 iput_final fs/inode.c:1654 [inline] iput.part.0+0x3fe/0x820 fs/inode.c:1680 iput+0x58/0x70 fs/inode.c:1670
Weakness: CWE-476
Which versions are affected by CVE-2021-47340?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2021-47340?
Apply the vendor's patch.
Is CVE-2021-47340 being exploited?
There is no known exploitation of CVE-2021-47340 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as DEBIAN-CVE-2021-47340, GHSA-ghv4-3pw7-86rj, UBUNTU-CVE-2021-47340.