Skip to content

Commit

Permalink
nfsd: get rid of cl_recdir field
Browse files Browse the repository at this point in the history 
Remove the cl_recdir field from the nfs4_client struct. Instead, just
compute it on the fly when and if it's needed, which is now only when
the legacy client tracking code is in effect.

The error handling in the legacy client tracker is also changed to
handle the case where md5 is unavailable. In that case, we'll warn
the admin with a KERN_ERR message and disable the client tracking.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
  • Loading branch information
Jeff Layton authored and J. Bruce Fields committed Nov 12, 2012
1 parent ac55fdc commit 2216d44
Show file tree
Hide file tree
Showing 3 changed files with 77 additions and 36 deletions.
93 changes: 74 additions & 19 deletions fs/nfsd/nfs4recover.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -103,45 +103,76 @@ md5_to_hex(char *out, char *md5)
*out = '\0';
}

__be32
nfs4_make_rec_clidname(char *dname, struct xdr_netobj *clname)
static int
nfs4_make_rec_clidname(char *dname, const struct xdr_netobj *clname)
{
struct xdr_netobj cksum;
struct hash_desc desc;
struct scatterlist sg;
__be32 status = nfserr_jukebox;
int status;

dprintk("NFSD: nfs4_make_rec_clidname for %.*s\n",
clname->len, clname->data);
desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP;
desc.tfm = crypto_alloc_hash("md5", 0, CRYPTO_ALG_ASYNC);
if (IS_ERR(desc.tfm))
if (IS_ERR(desc.tfm)) {
status = PTR_ERR(desc.tfm);
goto out_no_tfm;
}

cksum.len = crypto_hash_digestsize(desc.tfm);
cksum.data = kmalloc(cksum.len, GFP_KERNEL);
if (cksum.data == NULL)
if (cksum.data == NULL) {
status = -ENOMEM;
goto out;
}

sg_init_one(&sg, clname->data, clname->len);

if (crypto_hash_digest(&desc, &sg, sg.length, cksum.data))
status = crypto_hash_digest(&desc, &sg, sg.length, cksum.data);
if (status)
goto out;

md5_to_hex(dname, cksum.data);

status = nfs_ok;
status = 0;
out:
kfree(cksum.data);
crypto_free_hash(desc.tfm);
out_no_tfm:
return status;
}

/*
* If we had an error generating the recdir name for the legacy tracker
* then warn the admin. If the error doesn't appear to be transient,
* then disable recovery tracking.
*/
static void
legacy_recdir_name_error(int error)
{
printk(KERN_ERR "NFSD: unable to generate recoverydir "
"name (%d).\n", error);

/*
* if the algorithm just doesn't exist, then disable the recovery
* tracker altogether. The crypto libs will generally return this if
* FIPS is enabled as well.
*/
if (error == -ENOENT) {
printk(KERN_ERR "NFSD: disabling legacy clientid tracking. "
"Reboot recovery will not function correctly!\n");

/* the argument is ignored by the legacy exit function */
nfsd4_client_tracking_exit(NULL);
}
}

static void
nfsd4_create_clid_dir(struct nfs4_client *clp)
{
const struct cred *original_cred;
char *dname = clp->cl_recdir;
char dname[HEXDIR_LEN];
struct dentry *dir, *dentry;
struct nfs4_client_reclaim *crp;
int status;
Expand All @@ -152,6 +183,11 @@ nfsd4_create_clid_dir(struct nfs4_client *clp)
return;
if (!rec_file)
return;

status = nfs4_make_rec_clidname(dname, &clp->cl_name);
if (status)
return legacy_recdir_name_error(status);

status = nfs4_save_creds(&original_cred);
if (status < 0)
return;
Expand Down Expand Up @@ -186,7 +222,7 @@ nfsd4_create_clid_dir(struct nfs4_client *clp)
mutex_unlock(&dir->d_inode->i_mutex);
if (status == 0) {
if (in_grace) {
crp = nfs4_client_to_reclaim(clp->cl_recdir);
crp = nfs4_client_to_reclaim(dname);
if (crp)
crp->cr_clp = clp;
}
Expand Down Expand Up @@ -298,11 +334,16 @@ nfsd4_remove_clid_dir(struct nfs4_client *clp)
{
const struct cred *original_cred;
struct nfs4_client_reclaim *crp;
char dname[HEXDIR_LEN];
int status;

if (!rec_file || !test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
return;

status = nfs4_make_rec_clidname(dname, &clp->cl_name);
if (status)
return legacy_recdir_name_error(status);

status = mnt_want_write_file(rec_file);
if (status)
goto out;
Expand All @@ -312,13 +353,13 @@ nfsd4_remove_clid_dir(struct nfs4_client *clp)
if (status < 0)
goto out_drop_write;

status = nfsd4_unlink_clid_dir(clp->cl_recdir, HEXDIR_LEN-1);
status = nfsd4_unlink_clid_dir(dname, HEXDIR_LEN-1);
nfs4_reset_creds(original_cred);
if (status == 0) {
vfs_fsync(rec_file, 0);
if (in_grace) {
/* remove reclaim record */
crp = nfsd4_find_reclaim_client(clp->cl_recdir);
crp = nfsd4_find_reclaim_client(dname);
if (crp)
nfs4_remove_reclaim_record(crp);
}
Expand All @@ -328,7 +369,7 @@ nfsd4_remove_clid_dir(struct nfs4_client *clp)
out:
if (status)
printk("NFSD: Failed to remove expired client state directory"
" %.*s\n", HEXDIR_LEN, clp->cl_recdir);
" %.*s\n", HEXDIR_LEN, dname);
}

static int
Expand Down Expand Up @@ -500,14 +541,22 @@ nfs4_recoverydir(void)
static int
nfsd4_check_legacy_client(struct nfs4_client *clp)
{
int status;
char dname[HEXDIR_LEN];
struct nfs4_client_reclaim *crp;

/* did we already find that this client is stable? */
if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags))
return 0;

status = nfs4_make_rec_clidname(dname, &clp->cl_name);
if (status) {
legacy_recdir_name_error(status);
return status;
}

/* look for it in the reclaim hashtable otherwise */
crp = nfsd4_find_reclaim_client(clp->cl_recdir);
crp = nfsd4_find_reclaim_client(dname);
if (crp) {
set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags);
crp->cr_clp = clp;
Expand Down Expand Up @@ -993,7 +1042,7 @@ nfsd4_cltrack_legacy_topdir(void)
}

static char *
nfsd4_cltrack_legacy_recdir(const char *recdir)
nfsd4_cltrack_legacy_recdir(const struct xdr_netobj *name)
{
int copied;
size_t len;
Expand All @@ -1010,10 +1059,16 @@ nfsd4_cltrack_legacy_recdir(const char *recdir)
if (!result)
return result;

copied = snprintf(result, len, LEGACY_RECDIR_ENV_PREFIX "%s/%s",
nfs4_recoverydir(), recdir);
if (copied >= len) {
/* just return nothing if output was truncated */
copied = snprintf(result, len, LEGACY_RECDIR_ENV_PREFIX "%s/",
nfs4_recoverydir());
if (copied > (len - HEXDIR_LEN)) {
/* just return nothing if output will be truncated */
kfree(result);
return NULL;
}

copied = nfs4_make_rec_clidname(result + copied, name);
if (copied) {
kfree(result);
return NULL;
}
Expand Down Expand Up @@ -1126,7 +1181,7 @@ nfsd4_umh_cltrack_check(struct nfs4_client *clp)
dprintk("%s: can't allocate memory for upcall!\n", __func__);
return -ENOMEM;
}
legacy = nfsd4_cltrack_legacy_recdir(clp->cl_recdir);
legacy = nfsd4_cltrack_legacy_recdir(&clp->cl_name);
ret = nfsd4_umh_cltrack_upcall("check", hexid, legacy);
kfree(legacy);
kfree(hexid);
Expand Down
18 changes: 3 additions & 15 deletions fs/nfsd/nfs4state.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1299,7 +1299,7 @@ static struct nfs4_stid *find_stateid_by_type(struct nfs4_client *cl, stateid_t
return NULL;
}

static struct nfs4_client *create_client(struct xdr_netobj name, char *recdir,
static struct nfs4_client *create_client(struct xdr_netobj name,
struct svc_rqst *rqstp, nfs4_verifier *verf)
{
struct nfs4_client *clp;
Expand All @@ -1319,7 +1319,6 @@ static struct nfs4_client *create_client(struct xdr_netobj name, char *recdir,
return NULL;
}
idr_init(&clp->cl_stateids);
memcpy(clp->cl_recdir, recdir, HEXDIR_LEN);
atomic_set(&clp->cl_refcount, 0);
clp->cl_cb_state = NFSD4_CB_UNKNOWN;
INIT_LIST_HEAD(&clp->cl_idhash);
Expand Down Expand Up @@ -1616,7 +1615,6 @@ nfsd4_exchange_id(struct svc_rqst *rqstp,
{
struct nfs4_client *unconf, *conf, *new;
__be32 status;
char dname[HEXDIR_LEN];
char addr_str[INET6_ADDRSTRLEN];
nfs4_verifier verf = exid->verifier;
struct sockaddr *sa = svc_addr(rqstp);
Expand All @@ -1643,11 +1641,6 @@ nfsd4_exchange_id(struct svc_rqst *rqstp,
return nfserr_serverfault; /* no excuse :-/ */
}

status = nfs4_make_rec_clidname(dname, &exid->clname);

if (status)
return status;

/* Cases below refer to rfc 5661 section 18.35.4: */
nfs4_lock_state();
conf = find_confirmed_client_by_name(&exid->clname);
Expand Down Expand Up @@ -1701,7 +1694,7 @@ nfsd4_exchange_id(struct svc_rqst *rqstp,

/* case 1 (normal case) */
out_new:
new = create_client(exid->clname, dname, rqstp, &verf);
new = create_client(exid->clname, rqstp, &verf);
if (new == NULL) {
status = nfserr_jukebox;
goto out;
Expand Down Expand Up @@ -2236,12 +2229,7 @@ nfsd4_setclientid(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
nfs4_verifier clverifier = setclid->se_verf;
struct nfs4_client *conf, *unconf, *new;
__be32 status;
char dname[HEXDIR_LEN];

status = nfs4_make_rec_clidname(dname, &clname);
if (status)
return status;

/* Cases below refer to rfc 3530 section 14.2.33: */
nfs4_lock_state();
conf = find_confirmed_client_by_name(&clname);
Expand All @@ -2263,7 +2251,7 @@ nfsd4_setclientid(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
if (unconf)
expire_client(unconf);
status = nfserr_jukebox;
new = create_client(clname, dname, rqstp, &clverifier);
new = create_client(clname, rqstp, &clverifier);
if (new == NULL)
goto out;
if (conf && same_verf(&conf->cl_verifier, &clverifier))
Expand Down
2 changes: 0 additions & 2 deletions fs/nfsd/state.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -238,7 +238,6 @@ struct nfs4_client {
struct list_head cl_delegations;
struct list_head cl_lru; /* tail queue */
struct xdr_netobj cl_name; /* id generated by client */
char cl_recdir[HEXDIR_LEN]; /* recovery dir */
nfs4_verifier cl_verifier; /* generated by client */
time_t cl_time; /* time of last lease renewal */
struct sockaddr_storage cl_addr; /* client ipaddress */
Expand Down Expand Up @@ -482,7 +481,6 @@ extern int nfsd4_create_callback_queue(void);
extern void nfsd4_destroy_callback_queue(void);
extern void nfsd4_shutdown_callback(struct nfs4_client *);
extern void nfs4_put_delegation(struct nfs4_delegation *dp);
extern __be32 nfs4_make_rec_clidname(char *clidname, struct xdr_netobj *clname);
extern struct nfs4_client_reclaim *nfs4_client_to_reclaim(const char *name);
extern bool nfs4_has_reclaimed_state(const char *name);
extern void release_session_client(struct nfsd4_session *);
Expand Down

0 comments on commit 2216d44

Please sign in to comment.