CVEvulnerability
CVE-2026-97950
- Status
- Received
- Published
- 2026-09-25
- Last modified
- 2026-10-21
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Description
In the Linux kernel, the following vulnerability has been resolved:
configfs: pin the symlink target's dirent instead of chasing ->ci_dentry
create_link() reads the target's configfs_dirent from
item->ci_dentry->d_fsdata, relying on the item reference taken by
get_target(). That reference pins the item, not its dentry: the dentry is
pinned by DCACHE_PERSISTENT, which configfs_remove_dir() releases via
simple_rmdir() while the item is still alive. A symlink racing with rmdir
of its target can therefore find ->ci_dentry freed and its dirent
released, triggering WARN_ON(!atomic_read(&sd->s_count)) in configfs_get().
Take the dirent in get_target() as well, under ->d_lock and atomically
with the item reference, and pass it down to create_link(). A hashed
dentry has not been killed yet, so its ->d_fsdata reference keeps the
dirent alive there.
References
- https://git.kernel.org/stable/c/4f54beb2e7f6d399396466682fba3539bcdcb414 git.kernel.org
- https://git.kernel.org/stable/c/846ff40fd57a47e59a41f4e331ec3b34efaddc23 git.kernel.org
- https://git.kernel.org/stable/c/a44744454eafbc158e8c8e3ef8d207076410b195 git.kernel.org
- https://git.kernel.org/stable/c/a7c1290eef60711c10289c056ad32ed1f2b47b12 git.kernel.org
- https://git.kernel.org/stable/c/d47c5de1cd6bfbe1067fc310bf90e4e00205e839 git.kernel.org