diff options
| author | Trond Myklebust <trond.myklebust@primarydata.com> | 2016-09-22 13:38:54 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-10-28 03:01:31 -0400 |
| commit | c7a128f02ef89b8f4da86098c707ff229172cf63 (patch) | |
| tree | 3f04e1fd4b456e9650166e007e8e0ea6891da982 /fs | |
| parent | 79e7e444ed6cc249208798d1effea31945719c10 (diff) | |
NFSv4: nfs4_copy_delegation_stateid() must fail if the delegation is invalid
commit aa05c87f23efe417adc7ff9b4193b7201ec0dd79 upstream.
We must not allow the use of delegations that have been revoked or are
being returned.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Fixes: 869f9dfa4d6d ("NFSv4: Fix races between nfs_remove_bad_delegation()...")
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Tested-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/nfs/delegation.c | 17 |
1 files changed, 13 insertions, 4 deletions
diff --git a/fs/nfs/delegation.c b/fs/nfs/delegation.c index f73207409b2d..7af5eeabc80e 100644 --- a/fs/nfs/delegation.c +++ b/fs/nfs/delegation.c @@ -41,6 +41,17 @@ void nfs_mark_delegation_referenced(struct nfs_delegation *delegation) set_bit(NFS_DELEGATION_REFERENCED, &delegation->flags); } +static bool +nfs4_is_valid_delegation(const struct nfs_delegation *delegation, + fmode_t flags) +{ + if (delegation != NULL && (delegation->type & flags) == flags && + !test_bit(NFS_DELEGATION_REVOKED, &delegation->flags) && + !test_bit(NFS_DELEGATION_RETURNING, &delegation->flags)) + return true; + return false; +} + static int nfs4_do_check_delegation(struct inode *inode, fmode_t flags, bool mark) { @@ -50,9 +61,7 @@ nfs4_do_check_delegation(struct inode *inode, fmode_t flags, bool mark) flags &= FMODE_READ|FMODE_WRITE; rcu_read_lock(); delegation = rcu_dereference(NFS_I(inode)->delegation); - if (delegation != NULL && (delegation->type & flags) == flags && - !test_bit(NFS_DELEGATION_REVOKED, &delegation->flags) && - !test_bit(NFS_DELEGATION_RETURNING, &delegation->flags)) { + if (nfs4_is_valid_delegation(delegation, flags)) { if (mark) nfs_mark_delegation_referenced(delegation); ret = 1; @@ -893,7 +902,7 @@ bool nfs4_copy_delegation_stateid(nfs4_stateid *dst, struct inode *inode, flags &= FMODE_READ|FMODE_WRITE; rcu_read_lock(); delegation = rcu_dereference(nfsi->delegation); - ret = (delegation != NULL && (delegation->type & flags) == flags); + ret = nfs4_is_valid_delegation(delegation, flags); if (ret) { nfs4_stateid_copy(dst, &delegation->stateid); nfs_mark_delegation_referenced(delegation); |