[PATCH 5.2 073/162] NFSv4.1: Fix open stateid recovery

Greg Kroah-Hartman
2019-08-27T08:10:19Z

[ Upstream commit 27a30cf64a5cbe2105e4ff9613246b32d584766a ]

The logic for checking in nfs41_check_open_stateid() whether the state
is supported by a delegation is inverted. In addition, it makes more
sense to perform that check before we check for expired locks.

Fixes: 8a64c4ef106d1 ("NFSv4.1: Even if the stateid is OK,...")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
fs/nfs/nfs4proc.c | 65 +++++++++++++++++++++++++++--------------------
1 file changed, 38 insertions(+), 27 deletions(-)

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 420f2350c2781..74e1732a4bd01 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -1654,6 +1654,14 @@ static void nfs_state_set_open_stateid(struct nfs4_state *state,
write_sequnlock(&state->seqlock);
}

+static void nfs_state_clear_open_state_flags(struct nfs4_state *state)
+{
+ clear_bit(NFS_O_RDWR_STATE, &state->flags);
+ clear_bit(NFS_O_WRONLY_STATE, &state->flags);
+ clear_bit(NFS_O_RDONLY_STATE, &state->flags);
+ clear_bit(NFS_OPEN_STATE, &state->flags);
+}
+
static void nfs_state_set_delegation(struct nfs4_state *state,
const nfs4_stateid *deleg_stateid,
fmode_t fmode)
@@ -2049,13 +2057,7 @@ static int nfs4_open_recover(struct nfs4_opendata *opendata, struct nfs4_state *
{
int ret;

- /* Don't trigger recovery in nfs_test_and_clear_all_open_stateid */
- clear_bit(NFS_O_RDWR_STATE, &state->flags);
- clear_bit(NFS_O_WRONLY_STATE, &state->flags);
- clear_bit(NFS_O_RDONLY_STATE, &state->flags);
/* memory barrier prior to reading state->n_* */
- clear_bit(NFS_DELEGATED_STATE, &state->flags);
- clear_bit(NFS_OPEN_STATE, &state->flags);
smp_rmb();
ret = nfs4_open_recover_helper(opendata, FMODE_READ|FMODE_WRITE);
if (ret != 0)
@@ -2131,6 +2133,8 @@ static int nfs4_open_reclaim(struct nfs4_state_owner *sp, struct nfs4_state *sta
ctx = nfs4_state_find_open_context(state);
if (IS_ERR(ctx))
return -EAGAIN;
+ clear_bit(NFS_DELEGATED_STATE, &state->flags);
+ nfs_state_clear_open_state_flags(state);
ret = nfs4_do_open_reclaim(ctx, state);
put_nfs_open_context(ctx);
return ret;
@@ -2672,6 +2676,7 @@ static int nfs40_open_expired(struct nfs4_state_owner *sp, struct nfs4_state *st
{
/* NFSv4.0 doesn't allow for delegation recovery on open expire */
nfs40_clear_delegation_stateid(state);
+ nfs_state_clear_open_state_flags(state);
return nfs4_open_expired(sp, state);
}

@@ -2714,13 +2719,13 @@ out_free:
return -NFS4ERR_EXPIRED;
}

-static void nfs41_check_delegation_stateid(struct nfs4_state *state)
+static int nfs41_check_delegation_stateid(struct nfs4_state *state)
{
struct nfs_server *server = NFS_SERVER(state->inode);
nfs4_stateid stateid;
struct nfs_delegation *delegation;
const struct cred *cred = NULL;
- int status;
+ int status, ret = NFS_OK;

/* Get the delegation credential for use by test/free_stateid */
rcu_read_lock();
@@ -2728,20 +2733,15 @@ static void nfs41_check_delegation_stateid(struct nfs4_state *state)
if (delegation == NULL) {
rcu_read_unlock();
nfs_state_clear_delegation(state);
- return;
+ return NFS_OK;
}

nfs4_stateid_copy(&stateid, &delegation->stateid);
- if (test_bit(NFS_DELEGATION_REVOKED, &delegation->flags)) {
- rcu_read_unlock();
- nfs_state_clear_delegation(state);
- return;
- }

if (!test_and_clear_bit(NFS_DELEGATION_TEST_EXPIRED,
&delegation->flags)) {
rcu_read_unlock();
- return;
+ return NFS_OK;
}

if (delegation->cred)
@@ -2751,8 +2751,24 @@ static void nfs41_check_delegation_stateid(struct nfs4_state *state)
trace_nfs4_test_delegation_stateid(state, NULL, status);
if (status == -NFS4ERR_EXPIRED || status == -NFS4ERR_BAD_STATEID)
nfs_finish_clear_delegation_stateid(state, &stateid);
+ else
+ ret = status;

put_cred(cred);
+ return ret;
+}
+
+static void nfs41_delegation_recover_stateid(struct nfs4_state *state)
+{
+ nfs4_stateid tmp;
+
+ if (test_bit(NFS_DELEGATED_STATE, &state->flags) &&
+ nfs4_copy_delegation_stateid(state->inode, state->state,
+ &tmp, NULL) &&
+ nfs4_stateid_match_other(&state->stateid, &tmp))
+ nfs_state_set_delegation(state, &tmp, state->state);
+ else
+ nfs_state_clear_delegation(state);
}

/**
@@ -2822,21 +2838,12 @@ static int nfs41_check_open_stateid(struct nfs4_state *state)
const struct cred *cred = state->owner->so_cred;
int status;

- if (test_bit(NFS_OPEN_STATE, &state->flags) == 0) {
- if (test_bit(NFS_DELEGATED_STATE, &state->flags) == 0) {
- if (nfs4_have_delegation(state->inode, state->state))
- return NFS_OK;
- return -NFS4ERR_OPENMODE;
- }
+ if (test_bit(NFS_OPEN_STATE, &state->flags) == 0)
return -NFS4ERR_BAD_STATEID;
- }
status = nfs41_test_and_free_expired_stateid(server, stateid, cred);
trace_nfs4_test_open_stateid(state, NULL, status);
if (status == -NFS4ERR_EXPIRED || status == -NFS4ERR_BAD_STATEID) {
- clear_bit(NFS_O_RDONLY_STATE, &state->flags);
- clear_bit(NFS_O_WRONLY_STATE, &state->flags);
- clear_bit(NFS_O_RDWR_STATE, &state->flags);
- clear_bit(NFS_OPEN_STATE, &state->flags);
+ nfs_state_clear_open_state_flags(state);
stateid->type = NFS4_INVALID_STATEID_TYPE;
return status;
}
@@ -2849,7 +2856,11 @@ static int nfs41_open_expired(struct nfs4_state_owner *sp, struct nfs4_state *st
{
int status;

- nfs41_check_delegation_stateid(state);
+ status = nfs41_check_delegation_stateid(state);
+ if (status != NFS_OK)
+ return status;
+ nfs41_delegation_recover_stateid(state);
+
status = nfs41_check_expired_locks(state);
if (status != NFS_OK)
return status;
--
2.20.1