CVE-2026-46183

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

mm/damon/sysfs-schemes: protect path kfree() with damon_sysfs_lock

damon_sysfs_quot_goal->path can be read and written by users, via DAMON sysfs path file. It can also be indirectly read, for the parameters {on,off}line committing to DAMON. The reads for parameters committing are protected by damon_sysfs_lock to avoid the sysfs files being destroyed while any of the parameters are being read. But the user-driven direct reads and writes are not protected by any lock, while the write is deallocating the path-pointing buffer. As a result, the readers could read the already freed buffer (user-after-free). Note that the user-reads dont race when the same open file is used by the writer, due to kernfss open file locking. Nonetheless, doing the reads and writes with separate open files would be common. Fix it by protecting both the user-direct reads and writes with damon_sysfs_lock.

Weakness

The product calls free() twice on the same memory address.

Affected Software

Potential Mitigations

References

• https://git.kernel.org/stable/c/a34ca3e33da4b924c66bcca3729bf68ec5936910
• https://git.kernel.org/stable/c/cf3b71421ca00807328c6d9cd242f9de3b77a4bf