| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Date: Tue, 14 Mar 2017 09:07:09 +0200
From: Elena Reshetova <elena.reshetova@...el.com>
To: trond.myklebust@...marydata.com
Cc: linux-kernel@...r.kernel.org, linux-nfs@...r.kernel.org,
anna.schumaker@...app.com, peterz@...radead.org,
keescook@...omium.org, Elena Reshetova <elena.reshetova@...el.com>,
Hans Liljestrand <ishkamiel@...il.com>,
David Windsor <dwindsor@...il.com>
Subject: [PATCH 01/12] fs, nfsd: convert nfs4_stid.sc_count from atomic_t to refcount_t
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@...el.com>
Signed-off-by: Hans Liljestrand <ishkamiel@...il.com>
Signed-off-by: Kees Cook <keescook@...omium.org>
Signed-off-by: David Windsor <dwindsor@...il.com>
---
fs/nfsd/nfs4layouts.c | 4 ++--
fs/nfsd/nfs4state.c | 24 ++++++++++++------------
fs/nfsd/state.h | 3 ++-
3 files changed, 16 insertions(+), 15 deletions(-)
diff --git a/fs/nfsd/nfs4layouts.c b/fs/nfsd/nfs4layouts.c
index e122da6..fed0760 100644
--- a/fs/nfsd/nfs4layouts.c
+++ b/fs/nfsd/nfs4layouts.c
@@ -335,7 +335,7 @@ nfsd4_recall_file_layout(struct nfs4_layout_stateid *ls)
trace_layout_recall(&ls->ls_stid.sc_stateid);
- atomic_inc(&ls->ls_stid.sc_count);
+ refcount_inc(&ls->ls_stid.sc_count);
nfsd4_run_cb(&ls->ls_recall);
out_unlock:
@@ -440,7 +440,7 @@ nfsd4_insert_layout(struct nfsd4_layoutget *lgp, struct nfs4_layout_stateid *ls)
goto done;
}
- atomic_inc(&ls->ls_stid.sc_count);
+ refcount_inc(&ls->ls_stid.sc_count);
list_add_tail(&new->lo_perstate, &ls->ls_layouts);
new = NULL;
done:
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index e9ef50a..ea1ce57 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -656,7 +656,7 @@ struct nfs4_stid *nfs4_alloc_stid(struct nfs4_client *cl, struct kmem_cache *sla
stid->sc_stateid.si_opaque.so_id = new_id;
stid->sc_stateid.si_opaque.so_clid = cl->cl_clientid;
/* Will be incremented before return to client: */
- atomic_set(&stid->sc_count, 1);
+ refcount_set(&stid->sc_count, 1);
spin_lock_init(&stid->sc_lock);
/*
@@ -813,7 +813,7 @@ nfs4_put_stid(struct nfs4_stid *s)
might_lock(&clp->cl_lock);
- if (!atomic_dec_and_lock(&s->sc_count, &clp->cl_lock)) {
+ if (!refcount_dec_and_lock(&s->sc_count, &clp->cl_lock)) {
wake_up_all(&close_wq);
return;
}
@@ -913,7 +913,7 @@ hash_delegation_locked(struct nfs4_delegation *dp, struct nfs4_file *fp)
if (status)
return status;
++fp->fi_delegees;
- atomic_inc(&dp->dl_stid.sc_count);
+ refcount_inc(&dp->dl_stid.sc_count);
dp->dl_stid.sc_type = NFS4_DELEG_STID;
list_add(&dp->dl_perfile, &fp->fi_delegations);
list_add(&dp->dl_perclnt, &clp->cl_delegations);
@@ -1214,7 +1214,7 @@ static void put_ol_stateid_locked(struct nfs4_ol_stateid *stp,
WARN_ON_ONCE(!list_empty(&stp->st_locks));
- if (!atomic_dec_and_test(&s->sc_count)) {
+ if (!refcount_dec_and_test(&s->sc_count)) {
wake_up_all(&close_wq);
return;
}
@@ -2085,7 +2085,7 @@ find_stateid_by_type(struct nfs4_client *cl, stateid_t *t, char typemask)
s = find_stateid_locked(cl, t);
if (s != NULL) {
if (typemask & s->sc_type)
- atomic_inc(&s->sc_count);
+ refcount_inc(&s->sc_count);
else
s = NULL;
}
@@ -3515,7 +3515,7 @@ nfsd4_find_existing_open(struct nfs4_file *fp, struct nfsd4_open *open)
continue;
if (local->st_stateowner == &oo->oo_owner) {
ret = local;
- atomic_inc(&ret->st_stid.sc_count);
+ refcount_inc(&ret->st_stid.sc_count);
break;
}
}
@@ -3574,7 +3574,7 @@ init_open_stateid(struct nfs4_file *fp, struct nfsd4_open *open)
goto out_unlock;
open->op_stp = NULL;
- atomic_inc(&stp->st_stid.sc_count);
+ refcount_inc(&stp->st_stid.sc_count);
stp->st_stid.sc_type = NFS4_OPEN_STID;
INIT_LIST_HEAD(&stp->st_locks);
stp->st_stateowner = nfs4_get_stateowner(&oo->oo_owner);
@@ -3622,7 +3622,7 @@ move_to_close_lru(struct nfs4_ol_stateid *s, struct net *net)
* there should be no danger of the refcount going back up again at
* this point.
*/
- wait_event(close_wq, atomic_read(&s->st_stid.sc_count) == 2);
+ wait_event(close_wq, refcount_read(&s->st_stid.sc_count) == 2);
release_all_access(s);
if (s->st_stid.sc_file) {
@@ -3784,7 +3784,7 @@ static void nfsd_break_one_deleg(struct nfs4_delegation *dp)
* lock) we know the server hasn't removed the lease yet, we know
* it's safe to take a reference.
*/
- atomic_inc(&dp->dl_stid.sc_count);
+ refcount_inc(&dp->dl_stid.sc_count);
nfsd4_run_cb(&dp->dl_recall);
}
@@ -5069,7 +5069,7 @@ nfsd4_free_stateid(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
ret = nfserr_locks_held;
break;
case NFS4_LOCK_STID:
- atomic_inc(&s->sc_count);
+ refcount_inc(&s->sc_count);
spin_unlock(&cl->cl_lock);
ret = nfsd4_free_lock_stateid(stateid, s);
goto out;
@@ -5573,7 +5573,7 @@ init_lock_stateid(struct nfs4_ol_stateid *stp, struct nfs4_lockowner *lo,
lockdep_assert_held(&clp->cl_lock);
- atomic_inc(&stp->st_stid.sc_count);
+ refcount_inc(&stp->st_stid.sc_count);
stp->st_stid.sc_type = NFS4_LOCK_STID;
stp->st_stateowner = nfs4_get_stateowner(&lo->lo_owner);
get_nfs4_file(fp);
@@ -5599,7 +5599,7 @@ find_lock_stateid(struct nfs4_lockowner *lo, struct nfs4_file *fp)
list_for_each_entry(lst, &lo->lo_owner.so_stateids, st_perstateowner) {
if (lst->st_stid.sc_file == fp) {
- atomic_inc(&lst->st_stid.sc_count);
+ refcount_inc(&lst->st_stid.sc_count);
return lst;
}
}
diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h
index 005c911..f927aa4 100644
--- a/fs/nfsd/state.h
+++ b/fs/nfsd/state.h
@@ -36,6 +36,7 @@
#define _NFSD4_STATE_H
#include <linux/idr.h>
+#include <linux/refcount.h>
#include <linux/sunrpc/svc_xprt.h>
#include "nfsfh.h"
@@ -83,7 +84,7 @@ struct nfsd4_callback_ops {
* fields that are of general use to any stateid.
*/
struct nfs4_stid {
- atomic_t sc_count;
+ refcount_t sc_count;
#define NFS4_OPEN_STID 1
#define NFS4_LOCK_STID 2
#define NFS4_DELEG_STID 4
--
2.7.4
Powered by blists - more mailing lists