2022-01-27 11:51:14

by NeilBrown

[permalink] [raw]
Subject: [PATCH 1/4] nfsd: prepare for supporting admin-revocation of state

The NFSv4 protocol allows state to be revoked by the admin and has error
codes which allow this to be communicated to the client.

This patch
- introduces 3 new state-id types for revoked open, lock, and
delegation state. This requires the bitmask to be 'short',
not 'char'
- reports NFS4ERR_ADMIN_REVOKED when these are accessed
- introduces a per-client counter of these states and returns
SEQ4_STATUS_ADMIN_STATE_REVOKED when the counter is not zero
- introduces stub code to find all interesting states for a given
superblock so they can be revoked via the 'unlock_filesystem'
file in /proc/fs/nfsd/
No actual states are handled yet.

Signed-off-by: NeilBrown <[email protected]>
---
fs/nfsd/nfs4layouts.c | 2 +
fs/nfsd/nfs4state.c | 79 +++++++++++++++++++++++++++++++++++++++++++++++--
fs/nfsd/nfsctl.c | 1 +
fs/nfsd/nfsd.h | 1 +
fs/nfsd/state.h | 26 ++++++++++------
5 files changed, 95 insertions(+), 14 deletions(-)

diff --git a/fs/nfsd/nfs4layouts.c b/fs/nfsd/nfs4layouts.c
index 6d1b5bb051c5..211cbefa3d80 100644
--- a/fs/nfsd/nfs4layouts.c
+++ b/fs/nfsd/nfs4layouts.c
@@ -269,7 +269,7 @@ nfsd4_preprocess_layout_stateid(struct svc_rqst *rqstp,
{
struct nfs4_layout_stateid *ls;
struct nfs4_stid *stid;
- unsigned char typemask = NFS4_LAYOUT_STID;
+ unsigned short typemask = NFS4_LAYOUT_STID;
__be32 status;

if (create)
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 72900b89cf84..ad02b4ebe1b6 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -1575,6 +1575,55 @@ static void release_openowner(struct nfs4_openowner *oo)
nfs4_put_stateowner(&oo->oo_owner);
}

+static struct nfs4_stid *find_one_sb_stid(struct nfs4_client *clp,
+ struct super_block *sb,
+ unsigned short sc_types)
+{
+ unsigned long id = 0;
+ struct nfs4_stid *stid;
+
+ spin_lock(&clp->cl_lock);
+ do {
+ id += 1;
+ stid = idr_get_next_ul(&clp->cl_stateids, &id);
+ } while (stid &&
+ !((stid->sc_type & sc_types) &&
+ stid->sc_file->fi_inode->i_sb == sb));
+ if (stid)
+ refcount_inc(&stid->sc_count);
+ spin_unlock(&clp->cl_lock);
+ return stid;
+}
+
+void nfsd4_revoke_states(struct net *net, struct super_block *sb)
+{
+ struct nfsd_net *nn = net_generic(net, nfsd_net_id);
+ unsigned int idhashval;
+ unsigned short sc_types;
+
+ sc_types = 0;
+
+ spin_lock(&nn->client_lock);
+ for (idhashval = 0; idhashval < CLIENT_HASH_MASK; idhashval++) {
+ struct list_head *head = &nn->conf_id_hashtbl[idhashval];
+ struct nfs4_client *clp;
+ retry:
+ list_for_each_entry(clp, head, cl_idhash) {
+ struct nfs4_stid *stid = find_one_sb_stid(clp, sb,
+ sc_types);
+ if (stid) {
+ spin_unlock(&nn->client_lock);
+ switch (stid->sc_type) {
+ }
+ nfs4_put_stid(stid);
+ spin_lock(&nn->client_lock);
+ goto retry;
+ }
+ }
+ }
+ spin_unlock(&nn->client_lock);
+}
+
static inline int
hash_sessionid(struct nfs4_sessionid *sessionid)
{
@@ -2349,7 +2398,8 @@ find_stateid_locked(struct nfs4_client *cl, stateid_t *t)
}

static struct nfs4_stid *
-find_stateid_by_type(struct nfs4_client *cl, stateid_t *t, char typemask)
+find_stateid_by_type(struct nfs4_client *cl, stateid_t *t,
+ unsigned short typemask)
{
struct nfs4_stid *s;

@@ -2426,6 +2476,8 @@ static int client_info_show(struct seq_file *m, void *v)
}
seq_printf(m, "callback state: %s\n", cb_state2str(clp->cl_cb_state));
seq_printf(m, "callback address: %pISpc\n", &clp->cl_cb_conn.cb_addr);
+ seq_printf(m, "admin-revoked states: %d\n",
+ atomic_read(&clp->cl_admin_revoked));
drop_client(clp);

return 0;
@@ -3907,6 +3959,8 @@ nfsd4_sequence(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
}
if (!list_empty(&clp->cl_revoked))
seq->status_flags |= SEQ4_STATUS_RECALLABLE_STATE_REVOKED;
+ if (atomic_read(&clp->cl_admin_revoked))
+ seq->status_flags |= SEQ4_STATUS_ADMIN_STATE_REVOKED;
out_no_session:
if (conn)
free_conn(conn);
@@ -4361,6 +4415,11 @@ nfsd4_verify_open_stid(struct nfs4_stid *s)
break;
case NFS4_REVOKED_DELEG_STID:
ret = nfserr_deleg_revoked;
+ break;
+ case NFS4_ADMIN_REVOKED_STID:
+ case NFS4_ADMIN_REVOKED_DELEG_STID:
+ ret = nfserr_admin_revoked;
+ break;
}
return ret;
}
@@ -4893,6 +4952,11 @@ nfs4_check_deleg(struct nfs4_client *cl, struct nfsd4_open *open,
status = nfserr_deleg_revoked;
goto out;
}
+ if (deleg->dl_stid.sc_type == NFS4_ADMIN_REVOKED_DELEG_STID) {
+ nfs4_put_stid(&deleg->dl_stid);
+ status = nfserr_admin_revoked;
+ goto out;
+ }
flags = share_access_to_flags(open->op_share_access);
status = nfs4_check_delegmode(deleg, flags);
if (status) {
@@ -5840,6 +5904,11 @@ static __be32 nfsd4_validate_stateid(struct nfs4_client *cl, stateid_t *stateid)
case NFS4_REVOKED_DELEG_STID:
status = nfserr_deleg_revoked;
break;
+ case NFS4_ADMIN_REVOKED_STID:
+ case NFS4_ADMIN_REVOKED_LOCK_STID:
+ case NFS4_ADMIN_REVOKED_DELEG_STID:
+ status = nfserr_admin_revoked;
+ break;
case NFS4_OPEN_STID:
case NFS4_LOCK_STID:
status = nfsd4_check_openowner_confirmed(openlockstateid(s));
@@ -5858,7 +5927,7 @@ static __be32 nfsd4_validate_stateid(struct nfs4_client *cl, stateid_t *stateid)

__be32
nfsd4_lookup_stateid(struct nfsd4_compound_state *cstate,
- stateid_t *stateid, unsigned char typemask,
+ stateid_t *stateid, unsigned short typemask,
struct nfs4_stid **s, struct nfsd_net *nn)
{
__be32 status;
@@ -5893,6 +5962,10 @@ nfsd4_lookup_stateid(struct nfsd4_compound_state *cstate,
return nfserr_deleg_revoked;
return nfserr_bad_stateid;
}
+ if (((*s)->sc_type == NFS4_ADMIN_REVOKED_DELEG_STID) && !return_revoked) {
+ nfs4_put_stid(*s);
+ return nfserr_admin_revoked;
+ }
return nfs_ok;
}

@@ -6235,7 +6308,7 @@ static __be32 nfs4_seqid_op_checks(struct nfsd4_compound_state *cstate, stateid_
*/
static __be32
nfs4_preprocess_seqid_op(struct nfsd4_compound_state *cstate, u32 seqid,
- stateid_t *stateid, char typemask,
+ stateid_t *stateid, unsigned short typemask,
struct nfs4_ol_stateid **stpp,
struct nfsd_net *nn)
{
diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c
index b9f27fbcd768..2576867bdd71 100644
--- a/fs/nfsd/nfsctl.c
+++ b/fs/nfsd/nfsctl.c
@@ -323,6 +323,7 @@ static ssize_t write_unlock_fs(struct file *file, char *buf, size_t size)
* 3. Is that directory the root of an exported file system?
*/
error = nlmsvc_unlock_all_by_sb(path.dentry->d_sb);
+ nfsd4_revoke_states(netns(file), path.dentry->d_sb);

path_put(&path);
return error;
diff --git a/fs/nfsd/nfsd.h b/fs/nfsd/nfsd.h
index 3e5008b475ff..f9fdd4078956 100644
--- a/fs/nfsd/nfsd.h
+++ b/fs/nfsd/nfsd.h
@@ -249,6 +249,7 @@ void nfsd_lockd_shutdown(void);
#define nfserr_no_grace cpu_to_be32(NFSERR_NO_GRACE)
#define nfserr_reclaim_bad cpu_to_be32(NFSERR_RECLAIM_BAD)
#define nfserr_badname cpu_to_be32(NFSERR_BADNAME)
+#define nfserr_admin_revoked cpu_to_be32(NFS4ERR_ADMIN_REVOKED)
#define nfserr_cb_path_down cpu_to_be32(NFSERR_CB_PATH_DOWN)
#define nfserr_locked cpu_to_be32(NFSERR_LOCKED)
#define nfserr_wrongsec cpu_to_be32(NFSERR_WRONGSEC)
diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h
index 95457cfd37fc..8429bfc06216 100644
--- a/fs/nfsd/state.h
+++ b/fs/nfsd/state.h
@@ -88,17 +88,20 @@ struct nfsd4_callback_ops {
*/
struct nfs4_stid {
refcount_t sc_count;
-#define NFS4_OPEN_STID 1
-#define NFS4_LOCK_STID 2
-#define NFS4_DELEG_STID 4
+ struct list_head sc_cp_list;
+ unsigned short sc_type;
+#define NFS4_OPEN_STID BIT(0)
+#define NFS4_LOCK_STID BIT(1)
+#define NFS4_DELEG_STID BIT(2)
/* For an open stateid kept around *only* to process close replays: */
-#define NFS4_CLOSED_STID 8
+#define NFS4_CLOSED_STID BIT(3)
/* For a deleg stateid kept around only to process free_stateid's: */
-#define NFS4_REVOKED_DELEG_STID 16
-#define NFS4_CLOSED_DELEG_STID 32
-#define NFS4_LAYOUT_STID 64
- struct list_head sc_cp_list;
- unsigned char sc_type;
+#define NFS4_REVOKED_DELEG_STID BIT(4)
+#define NFS4_CLOSED_DELEG_STID BIT(5)
+#define NFS4_LAYOUT_STID BIT(6)
+#define NFS4_ADMIN_REVOKED_STID BIT(7)
+#define NFS4_ADMIN_REVOKED_LOCK_STID BIT(8)
+#define NFS4_ADMIN_REVOKED_DELEG_STID BIT(9)
stateid_t sc_stateid;
spinlock_t sc_lock;
struct nfs4_client *sc_client;
@@ -330,6 +333,7 @@ struct nfs4_client {
clientid_t cl_clientid; /* generated by server */
nfs4_verifier cl_confirm; /* generated by server */
u32 cl_minorversion;
+ atomic_t cl_admin_revoked; /* count of admin-revoked states */
/* NFSv4.1 client implementation id: */
struct xdr_netobj cl_nii_domain;
struct xdr_netobj cl_nii_name;
@@ -645,7 +649,7 @@ extern __be32 nfs4_preprocess_stateid_op(struct svc_rqst *rqstp,
stateid_t *stateid, int flags, struct nfsd_file **filp,
struct nfs4_stid **cstid);
__be32 nfsd4_lookup_stateid(struct nfsd4_compound_state *cstate,
- stateid_t *stateid, unsigned char typemask,
+ stateid_t *stateid, unsigned short typemask,
struct nfs4_stid **s, struct nfsd_net *nn);
struct nfs4_stid *nfs4_alloc_stid(struct nfs4_client *cl, struct kmem_cache *slab,
void (*sc_free)(struct nfs4_stid *));
@@ -691,6 +695,8 @@ static inline void get_nfs4_file(struct nfs4_file *fi)
}
struct nfsd_file *find_any_file(struct nfs4_file *f);

+void nfsd4_revoke_states(struct net *net, struct super_block *sb);
+
/* grace period management */
void nfsd4_end_grace(struct nfsd_net *nn);




2022-01-28 00:29:20

by kernel test robot

[permalink] [raw]
Subject: Re: [PATCH 1/4] nfsd: prepare for supporting admin-revocation of state

Hi NeilBrown,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on linus/master]
[also build test ERROR on v5.17-rc1 next-20220127]
[cannot apply to cel-2.6/for-next]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url: https://github.com/0day-ci/linux/commits/NeilBrown/nfsd-allow-NFSv4-state-to-be-revoked/20220127-130132
base: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 0280e3c58f92b2fe0e8fbbdf8d386449168de4a8
config: parisc-defconfig (https://download.01.org/0day-ci/archive/20220127/[email protected]/config)
compiler: hppa-linux-gcc (GCC) 11.2.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/0day-ci/linux/commit/36a49da0c1204b769399e692f540bf2a6332f89a
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review NeilBrown/nfsd-allow-NFSv4-state-to-be-revoked/20220127-130132
git checkout 36a49da0c1204b769399e692f540bf2a6332f89a
# save the config file to linux build tree
mkdir build_dir
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross O=build_dir ARCH=parisc SHELL=/bin/bash

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <[email protected]>

All errors (new ones prefixed by >>, old ones prefixed by <<):

>> ERROR: modpost: "nfsd4_revoke_states" [fs/nfsd/nfsd.ko] undefined!

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/[email protected]

2022-01-28 07:10:56

by kernel test robot

[permalink] [raw]
Subject: Re: [PATCH 1/4] nfsd: prepare for supporting admin-revocation of state

Hi NeilBrown,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on linus/master]
[also build test ERROR on v5.17-rc1 next-20220127]
[cannot apply to cel-2.6/for-next]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url: https://github.com/0day-ci/linux/commits/NeilBrown/nfsd-allow-NFSv4-state-to-be-revoked/20220127-130132
base: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 0280e3c58f92b2fe0e8fbbdf8d386449168de4a8
config: s390-randconfig-r004-20220126 (https://download.01.org/0day-ci/archive/20220127/[email protected]/config)
compiler: s390-linux-gcc (GCC) 11.2.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/0day-ci/linux/commit/36a49da0c1204b769399e692f540bf2a6332f89a
git remote add linux-review https://github.com/0day-ci/linux
git fetch --no-tags linux-review NeilBrown/nfsd-allow-NFSv4-state-to-be-revoked/20220127-130132
git checkout 36a49da0c1204b769399e692f540bf2a6332f89a
# save the config file to linux build tree
mkdir build_dir
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross O=build_dir ARCH=s390 SHELL=/bin/bash

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <[email protected]>

All errors (new ones prefixed by >>):

s390-linux-ld: fs/nfsd/nfsctl.o: in function `write_unlock_fs':
>> nfsctl.c:(.text+0x302): undefined reference to `nfsd4_revoke_states'

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/[email protected]