summaryrefslogtreecommitdiffstats
path: root/fs/nfs/delegation.c
diff options
context:
space:
mode:
authorTrond Myklebust <Trond.Myklebust@netapp.com>2009-06-17 22:23:00 +0200
committerTrond Myklebust <Trond.Myklebust@netapp.com>2009-06-17 22:23:00 +0200
commit3f09df70e3a33590ae5a97b8a15486d3711c7065 (patch)
tree18f5c9115aa79dd2cab5f87d7024bea5460ca0af /fs/nfs/delegation.c
parentNFSv4: Handle more errors when recovering open file and locking state (diff)
downloadlinux-3f09df70e3a33590ae5a97b8a15486d3711c7065.tar.xz
linux-3f09df70e3a33590ae5a97b8a15486d3711c7065.zip
NFS: Ensure we always hold the BKL when dereferencing inode->i_flock
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Diffstat (limited to 'fs/nfs/delegation.c')
-rw-r--r--fs/nfs/delegation.c16
1 files changed, 14 insertions, 2 deletions
diff --git a/fs/nfs/delegation.c b/fs/nfs/delegation.c
index d4f669f0683e..af05b918cb5b 100644
--- a/fs/nfs/delegation.c
+++ b/fs/nfs/delegation.c
@@ -70,15 +70,24 @@ static int nfs_delegation_claim_locks(struct nfs_open_context *ctx, struct nfs4_
struct file_lock *fl;
int status = 0;
+ if (inode->i_flock == NULL)
+ goto out;
+
+ /* Protect inode->i_flock using the BKL */
+ lock_kernel();
for (fl = inode->i_flock; fl != NULL; fl = fl->fl_next) {
if (!(fl->fl_flags & (FL_POSIX|FL_FLOCK)))
continue;
if (nfs_file_open_context(fl->fl_file) != ctx)
continue;
+ unlock_kernel();
status = nfs4_lock_delegation_recall(state, fl);
if (status < 0)
- break;
+ goto out;
+ lock_kernel();
}
+ unlock_kernel();
+out:
return status;
}
@@ -256,7 +265,10 @@ static int __nfs_inode_return_delegation(struct inode *inode, struct nfs_delegat
struct nfs_inode *nfsi = NFS_I(inode);
nfs_msync_inode(inode);
- /* Guard against new delegated open calls */
+ /*
+ * Guard against new delegated open/lock/unlock calls and against
+ * state recovery
+ */
down_write(&nfsi->rwsem);
nfs_delegation_claim_opens(inode, &delegation->stateid);
up_write(&nfsi->rwsem);