CVE-2026-97950

Summary

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.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux7063fbf2261194f72ee75afca67b3b38b554b5fa < 4f54beb2e7f6d399396466682fba3539bcdcb414affected
LinuxLinux7063fbf2261194f72ee75afca67b3b38b554b5fa < d47c5de1cd6bfbe1067fc310bf90e4e00205e839affected
LinuxLinux7063fbf2261194f72ee75afca67b3b38b554b5fa < a7c1290eef60711c10289c056ad32ed1f2b47b12affected
LinuxLinux2.6.16affected
LinuxLinux0 < 2.6.16unaffected
LinuxLinux6.18.53 <= 6.18.*unaffected
LinuxLinux7.2.7 <= 7.2.*unaffected
LinuxLinux7.3-rc3 <= *unaffected

Weaknesses

References