NLM: Defend against file_lock changes after vfs_test_lock()

Instead of trusting that struct file_lock returns completely unchanged
after vfs_test_lock() when there's no conflicting lock, stash away our
nlm_lockowner reference so we can properly release it for all cases.

This defends against another file_lock implementation overwriting fl_owner
when the return type is F_UNLCK.

Reported-by: Roberto Bergantinos Corpas <rbergant@redhat.com>
Tested-by: Roberto Bergantinos Corpas <rbergant@redhat.com>
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
This commit is contained in:
Benjamin Coddington
2022-06-13 09:40:06 -04:00
committed by Chuck Lever
parent c770f31d8f
commit 184cefbe62
4 changed files with 9 additions and 11 deletions

View File

@@ -292,6 +292,7 @@ void nlmsvc_locks_init_private(struct file_lock *, struct nlm_host *, pid_t);
__be32 nlm_lookup_file(struct svc_rqst *, struct nlm_file **,
struct nlm_lock *);
void nlm_release_file(struct nlm_file *);
void nlmsvc_put_lockowner(struct nlm_lockowner *);
void nlmsvc_release_lockowner(struct nlm_lock *);
void nlmsvc_mark_resources(struct net *);
void nlmsvc_free_host_resources(struct nlm_host *);