CVE-2022-49277 jffs2: fix memory leak in jffs2_do_mount_fs
A memory leak in the Linux kernel's JFFS2 filesystem allows attackers to cause a denial of service by exhausting system memory.
- 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-2022-49277?
CVE-2022-49277 is a medium-severity denial of service vulnerability in Linux kernel, published on 26 Feb 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:
jffs2: fix memory leak in jffs2_do_mount_fs
If jffs2_build_filesystem() in jffs2_do_mount_fs() returns an error, we can observe the following kmemleak report:
-------------------------------------------- unreferenced object 0xffff88811b25a640 (size 64): comm "mount", pid 691, jiffies 4294957728 (age 71.952s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffffffa493be24>] kmem_cache_alloc_trace+0x584/0x880 [<ffffffffa5423a06>] jffs2_sum_init+0x86/0x130 [<ffffffffa5400e58>] jffs2_do_mount_fs+0x798/0xac0 [<ffffffffa540acf3>] jffs2_do_fill_super+0x383/0xc30 [<ffffffffa540c00a>] jffs2_fill_super+0x2ea/0x4c0 [...] unreferenced object 0xffff88812c760000 (size 65536): comm "mount", pid 691, jiffies 4294957728 (age 71.952s) hex dump (first 32 bytes): bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb ................ bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb bb ................ backtrace: [<ffffffffa493a449>] __kmalloc+0x6b9/0x910 [<ffffffffa5423a57>] jffs2_sum_init+0xd7/0x130 [<ffffffffa5400e58>] jffs2_do_mount_fs+0x798/0xac0 [<ffffffffa540acf3>] jffs2_do_fill_super+0x383/0xc30 [<ffffffffa540c00a>] jffs2_fill_super+0x2ea/0x4c0 [...] --------------------------------------------
This is because the resources allocated in jffs2_sum_init() are not released. Call jffs2_sum_exit() to release these resources to solve the problem.
Weakness: CWE-401
Which versions are affected by CVE-2022-49277?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2022-49277?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2022-49277 being exploited?
There is no known exploitation of CVE-2022-49277 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as DEBIAN-CVE-2022-49277, GHSA-rfv9-hghg-chfq, UBUNTU-CVE-2022-49277.