From 83bfff23e9ed19f37c4ef0bba84e75bd88e5cf21 Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Sat, 11 Jul 2015 06:43:03 -0400 Subject: [PATCH] nfs4: have do_vfs_lock take an inode pointer Now that we have file locking helpers that can deal with an inode instead of a filp, we can change the NFSv4 locking code to use that instead. This should fix the case where we have a filp that is closed while flock or OFD locks are set on it, and the task is signaled so that it doesn't wait for the LOCKU reply to come in before the filp is freed. At that point we can end up with a use-after-free with the current code, which relies on dereferencing the fl_file in the lock request. Signed-off-by: Jeff Layton Reviewed-by: "J. Bruce Fields" Tested-by: "J. Bruce Fields" --- fs/nfs/nfs4proc.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index 60be01f69b84..8bee93469617 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -5439,15 +5439,15 @@ static int nfs4_proc_getlk(struct nfs4_state *state, int cmd, struct file_lock * return err; } -static int do_vfs_lock(struct file *file, struct file_lock *fl) +static int do_vfs_lock(struct inode *inode, struct file_lock *fl) { int res = 0; switch (fl->fl_flags & (FL_POSIX|FL_FLOCK)) { case FL_POSIX: - res = posix_lock_file_wait(file, fl); + res = posix_lock_inode_wait(inode, fl); break; case FL_FLOCK: - res = flock_lock_file_wait(file, fl); + res = flock_lock_inode_wait(inode, fl); break; default: BUG(); @@ -5507,7 +5507,7 @@ static void nfs4_locku_done(struct rpc_task *task, void *data) switch (task->tk_status) { case 0: renew_lease(calldata->server, calldata->timestamp); - do_vfs_lock(calldata->fl.fl_file, &calldata->fl); + do_vfs_lock(calldata->lsp->ls_state->inode, &calldata->fl); if (nfs4_update_lock_stateid(calldata->lsp, &calldata->res.stateid)) break; @@ -5615,7 +5615,7 @@ static int nfs4_proc_unlck(struct nfs4_state *state, int cmd, struct file_lock * mutex_lock(&sp->so_delegreturn_mutex); /* Exclude nfs4_reclaim_open_stateid() - note nesting! */ down_read(&nfsi->rwsem); - if (do_vfs_lock(request->fl_file, request) == -ENOENT) { + if (do_vfs_lock(inode, request) == -ENOENT) { up_read(&nfsi->rwsem); mutex_unlock(&sp->so_delegreturn_mutex); goto out; @@ -5756,7 +5756,7 @@ static void nfs4_lock_done(struct rpc_task *task, void *calldata) data->timestamp); if (data->arg.new_lock) { data->fl.fl_flags &= ~(FL_SLEEP | FL_ACCESS); - if (do_vfs_lock(data->fl.fl_file, &data->fl) < 0) { + if (do_vfs_lock(lsp->ls_state->inode, &data->fl) < 0) { rpc_restart_call_prepare(task); break; } @@ -5998,7 +5998,7 @@ static int _nfs4_proc_setlk(struct nfs4_state *state, int cmd, struct file_lock if (status != 0) goto out; request->fl_flags |= FL_ACCESS; - status = do_vfs_lock(request->fl_file, request); + status = do_vfs_lock(state->inode, request); if (status < 0) goto out; down_read(&nfsi->rwsem); @@ -6006,7 +6006,7 @@ static int _nfs4_proc_setlk(struct nfs4_state *state, int cmd, struct file_lock /* Yes: cache locks! */ /* ...but avoid races with delegation recall... */ request->fl_flags = fl_flags & ~FL_SLEEP; - status = do_vfs_lock(request->fl_file, request); + status = do_vfs_lock(state->inode, request); up_read(&nfsi->rwsem); goto out; } -- 2.20.1