NFSv4: Ensure correct locking when accessing the 'lock_states' list
There are currently 2 places in the state recovery code, where we do not
take sufficient precautions before accessing the state->lock_states. In
both cases, we should be holding the state->state_lock.
Reported-by: Pascal Bouchareine <pascal@gandi.net>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c
index da8d73e..6a7107a 100644
--- a/fs/nfs/nfs4state.c
+++ b/fs/nfs/nfs4state.c
@@ -1156,11 +1156,13 @@
if (status >= 0) {
status = nfs4_reclaim_locks(state, ops);
if (status >= 0) {
+ spin_lock(&state->state_lock);
list_for_each_entry(lock, &state->lock_states, ls_locks) {
if (!(lock->ls_flags & NFS_LOCK_INITIALIZED))
printk("%s: Lock reclaim failed!\n",
__func__);
}
+ spin_unlock(&state->state_lock);
nfs4_put_open_state(state);
goto restart;
}
@@ -1224,10 +1226,12 @@
clear_bit(NFS_O_RDONLY_STATE, &state->flags);
clear_bit(NFS_O_WRONLY_STATE, &state->flags);
clear_bit(NFS_O_RDWR_STATE, &state->flags);
+ spin_lock(&state->state_lock);
list_for_each_entry(lock, &state->lock_states, ls_locks) {
lock->ls_seqid.flags = 0;
lock->ls_flags &= ~NFS_LOCK_INITIALIZED;
}
+ spin_unlock(&state->state_lock);
}
static void nfs4_reset_seqids(struct nfs_server *server,