diff options
| author | Trond Myklebust <Trond.Myklebust@netapp.com> | 2009-06-18 00:23:00 +0400 |
|---|---|---|
| committer | Trond Myklebust <Trond.Myklebust@netapp.com> | 2009-06-18 00:23:00 +0400 |
| commit | 3f09df70e3a33590ae5a97b8a15486d3711c7065 (patch) | |
| tree | 18f5c9115aa79dd2cab5f87d7024bea5460ca0af /fs/nfs | |
| parent | 965b5d679146c9f69bc0325388bb9ed357863c4f (diff) | |
| download | linux-3f09df70e3a33590ae5a97b8a15486d3711c7065.tar.xz | |
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')
| -rw-r--r-- | fs/nfs/delegation.c | 16 | ||||
| -rw-r--r-- | fs/nfs/nfs4state.c | 9 |
2 files changed, 23 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); diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c index 6e094e95cf0f..0b2a19bfe5a0 100644 --- a/fs/nfs/nfs4state.c +++ b/fs/nfs/nfs4state.c @@ -847,12 +847,19 @@ static int nfs4_reclaim_locks(struct nfs4_state *state, const struct nfs4_state_ struct file_lock *fl; int status = 0; + if (inode->i_flock == NULL) + return 0; + + /* Guard against delegation returns and new lock/unlock calls */ down_write(&nfsi->rwsem); + /* 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)->state != state) continue; + unlock_kernel(); status = ops->recover_lock(state, fl); switch (status) { case 0: @@ -875,7 +882,9 @@ static int nfs4_reclaim_locks(struct nfs4_state *state, const struct nfs4_state_ /* kill_proc(fl->fl_pid, SIGLOST, 1); */ status = 0; } + lock_kernel(); } + unlock_kernel(); out: up_write(&nfsi->rwsem); return status; |