From 8c7b389e532e964f07057dac8a56c43465544759 Mon Sep 17 00:00:00 2001 From: Peter Staubach Date: Sat, 20 May 2006 14:59:56 -0700 Subject: [PATCH] NFS server subtree_check returns dubious value Address a problem found when a Linux NFS server uses the "subtree_check" export option. The "subtree_check" NFS export option was designed to prohibit a client from using a file handle for which it should not have permission. The algorithm used is to ensure that the entire path to the file being referenced is accessible to the user attempting to use the file handle. If some part of the path is not accessible, then the operation is aborted and the appropriate version of ESTALE is returned to the NFS client. The error, ESTALE, is unfortunate in that it causes NFS clients to make certain assumptions about the continued existence of the file. They assume that the file no longer exists and refuse to attempt to access it again. In this case, the file really does exist, but access was denied by the server for a particular user. A better error to return would be an EACCES sort of error. This would inform the client that the particular operation that it was attempting was not allowed, without the nasty side effects of the ESTALE error. Signed-off-by: Peter Staubach Acked-By: NeilBrown Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/exportfs/expfs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs/exportfs') diff --git a/fs/exportfs/expfs.c b/fs/exportfs/expfs.c index b06b54f1bbbb..4c39009350f3 100644 --- a/fs/exportfs/expfs.c +++ b/fs/exportfs/expfs.c @@ -102,7 +102,7 @@ find_exported_dentry(struct super_block *sb, void *obj, void *parent, if (acceptable(context, result)) return result; if (S_ISDIR(result->d_inode->i_mode)) { - /* there is no other dentry, so fail */ + err = -EACCES; goto err_result; } -- cgit v1.2.3