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| author | Trond Myklebust <Trond.Myklebust@netapp.com> | 2012-03-19 21:17:18 +0100 |
|---|---|---|
| committer | Trond Myklebust <Trond.Myklebust@netapp.com> | 2012-03-20 18:08:25 +0100 |
| commit | 5ae67c4fee869c9b3c87b727a9ea511b6326b834 (patch) | |
| tree | 68fe22b71462c6e13eff3a6d637b79371c77441e | |
| parent | NFS: ncommit count is being double decremented (diff) | |
| download | linux-5ae67c4fee869c9b3c87b727a9ea511b6326b834.tar.xz linux-5ae67c4fee869c9b3c87b727a9ea511b6326b834.zip | |
NFSv4: It is not safe to dereference lsp->ls_state in release_lockowner
It is quite possible for the release_lockowner RPC call to race with the
close RPC call, in which case, we cannot dereference lsp->ls_state in
order to find the nfs_server.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
| -rw-r--r-- | fs/nfs/nfs4_fs.h | 2 | ||||
| -rw-r--r-- | fs/nfs/nfs4proc.c | 4 | ||||
| -rw-r--r-- | fs/nfs/nfs4state.c | 8 |
3 files changed, 7 insertions, 7 deletions
diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h index b47bdb9c1612..97ecc863dd76 100644 --- a/fs/nfs/nfs4_fs.h +++ b/fs/nfs/nfs4_fs.h @@ -340,7 +340,7 @@ extern void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid); extern void nfs_release_seqid(struct nfs_seqid *seqid); extern void nfs_free_seqid(struct nfs_seqid *seqid); -extern void nfs4_free_lock_state(struct nfs4_lock_state *lsp); +extern void nfs4_free_lock_state(struct nfs_server *server, struct nfs4_lock_state *lsp); extern const nfs4_stateid zero_stateid; diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index 5e0961acfef4..d41d97fb4cb9 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -4760,13 +4760,14 @@ out: struct nfs_release_lockowner_data { struct nfs4_lock_state *lsp; + struct nfs_server *server; struct nfs_release_lockowner_args args; }; static void nfs4_release_lockowner_release(void *calldata) { struct nfs_release_lockowner_data *data = calldata; - nfs4_free_lock_state(data->lsp); + nfs4_free_lock_state(data->server, data->lsp); kfree(calldata); } @@ -4788,6 +4789,7 @@ int nfs4_release_lockowner(struct nfs4_lock_state *lsp) if (!data) return -ENOMEM; data->lsp = lsp; + data->server = server; data->args.lock_owner.clientid = server->nfs_client->cl_clientid; data->args.lock_owner.id = lsp->ls_seqid.owner_id; data->args.lock_owner.s_dev = server->s_dev; diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c index 12b068f2ec91..0f43414eb25a 100644 --- a/fs/nfs/nfs4state.c +++ b/fs/nfs/nfs4state.c @@ -791,10 +791,8 @@ out_free: return NULL; } -void nfs4_free_lock_state(struct nfs4_lock_state *lsp) +void nfs4_free_lock_state(struct nfs_server *server, struct nfs4_lock_state *lsp) { - struct nfs_server *server = lsp->ls_state->owner->so_server; - ida_simple_remove(&server->lockowner_id, lsp->ls_seqid.owner_id); nfs4_destroy_seqid_counter(&lsp->ls_seqid); kfree(lsp); @@ -828,7 +826,7 @@ static struct nfs4_lock_state *nfs4_get_lock_state(struct nfs4_state *state, fl_ } spin_unlock(&state->state_lock); if (new != NULL) - nfs4_free_lock_state(new); + nfs4_free_lock_state(state->owner->so_server, new); return lsp; } @@ -853,7 +851,7 @@ void nfs4_put_lock_state(struct nfs4_lock_state *lsp) if (nfs4_release_lockowner(lsp) == 0) return; } - nfs4_free_lock_state(lsp); + nfs4_free_lock_state(lsp->ls_state->owner->so_server, lsp); } static void nfs4_fl_copy_lock(struct file_lock *dst, struct file_lock *src) |