Описание
In the Linux kernel, the following vulnerability has been resolved:
NFSD: Prevent client use-after-free during export state revocation
nfsd4_revoke_export_states() has the same use-after-free as nfsd4_revoke_states(): it drops nn->client_lock across revoke_one_stid() and the following read of clp->cl_minorversion, but the stateid reference it holds does not pin the client. A teardown racing the dropped lock can free the client while revoke_one_stid() still dereferences it.
exportfs -u drives this path through NFSD_CMD_UNLOCK_EXPORT, so an administrator removing an export can race a client expiry.
Skip a client that is already expiring and otherwise pin it with cl_rpc_users under client_lock before dropping the lock, matching nfsd4_revoke_states().
EPSS
9.8 Critical
CVSS3
Дефекты
Связанные уязвимости
(In the Linux kernel, the following vulnerability has been resolved: N ...)
In the Linux kernel, the following vulnerability has been resolved: N ...
In the Linux kernel, the following vulnerability has been resolved: NFSD: Prevent client use-after-free during export state revocation nfsd4_revoke_export_states() has the same use-after-free as nfsd4_revoke_states(): it drops nn->client_lock across revoke_one_stid() and the following read of clp->cl_minorversion, but the stateid reference it holds does not pin the client. A teardown racing the dropped lock can free the client while revoke_one_stid() still dereferences it. exportfs -u drives this path through NFSD_CMD_UNLOCK_EXPORT, so an administrator removing an export can race a client expiry. Skip a client that is already expiring and otherwise pin it with cl_rpc_users under client_lock before dropping the lock, matching nfsd4_revoke_states().
EPSS
9.8 Critical
CVSS3