CVE-2026-80592 samples/damon/mtier: fail early if address range parameters are invalid
A local attacker with high privileges can trigger a kernel warning and potential instability by enabling the DAMON mtier sample module with invalid address parameters.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-80592?
CVE-2026-80592 is a denial of service vulnerability in Linux, published on 28 Aug 2026. 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:
samples/damon/mtier: fail early if address range parameters are invalid
The comment on top of `struct damon_region` clearly says that
For any use case, @ar should be non-zero positive size.
which is now verified in damon_verify_new_region() if the kernel is built with DAMON_DEBUG_SANITY.
The WARN_ONCE() can be triggered if the mtier sample module is enabled before node{0,1}_{start,end}_addr have been properly initialized, which is obviously not good.
------------[ cut here ]------------ start 0 >= end 0 WARNING: mm/damon/core.c:217 at damon_new_region+0xf4/0x118, CPU#59: bash/341468 Call trace: damon_new_region+0xf4/0x118 (P) damon_set_regions+0xfc/0x3c0 damon_sample_mtier_build_ctx+0xe8/0x3a8 damon_sample_mtier_start+0x1c/0x90 damon_sample_mtier_enable_store+0x98/0xb0 param_attr_store+0xb4/0x128 module_attr_store+0x2c/0x50 sysfs_kf_write+0x58/0x90 kernfs_fop_write_iter+0x16c/0x238 vfs_write+0x2c0/0x370 ksys_write+0x74/0x118 __arm64_sys_write+0x24/0x38 invoke_syscall+0xa8/0x118 el0_svc_common.constprop.0+0x48/0xf0 do_el0_svc+0x24/0x38 el0_svc+0x54/0x370 el0t_64_sync_handler+0xa0/0xe8 el0t_64_sync+0x1ac/0x1b0 ---[ end trace 0000000000000000 ]---
Note that the same issue can happen if detect_node_addresses is true, and node 0 or 1 is memoryless. Fix it together by checking the validity of parameters right before damon_new_region() and fail early if they're invalid.
Which versions are affected by CVE-2026-80592?
How do I fix CVE-2026-80592?
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-2026-80592 being exploited?
There is no known exploitation of CVE-2026-80592 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-80592, DEBIAN-CVE-2026-80592, GHSA-m63c-95f6-2rwg, UBUNTU-CVE-2026-80592.