[PATCH] fuse: clean up request size limit checking

Change the way a too large request is handled.  Until now in this case the
device read returned -EINVAL and the operation returned -EIO.

Make it more flexibible by not returning -EINVAL from the read, but restarting
it instead.

Also remove the fixed limit on setxattr data and let the filesystem provide as
large a read buffer as it needs to handle the extended attribute data.

The symbolic link length is already checked by VFS to be less than PATH_MAX,
so the extra check against FUSE_SYMLINK_MAX is not needed.

The check in fuse_create_open() against FUSE_NAME_MAX is not needed, since the
dentry has already been looked up, and hence the name already checked.

Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 6 insertions, 3 deletions

diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h
index 2d4835e54c908..17fd368559cdd 100644
--- a/fs/fuse/fuse_i.h
+++ b/fs/fuse/fuse_i.h
@@ -21,6 +21,12 @@
 /** If more requests are outstanding, then the operation will block */
 #define FUSE_MAX_OUTSTANDING 10
 
+/** Maximum size of data in a write request */
+#define FUSE_MAX_WRITE 4096
+
+/** It could be as large as PATH_MAX, but would that have any uses? */
+#define FUSE_NAME_MAX 1024
+
 /** If the FUSE_DEFAULT_PERMISSIONS flag is given, the filesystem
     module will check permissions based on the file mode.  Otherwise no
     permission checking is done in the kernel */
@@ -108,9 +114,6 @@ struct fuse_out {
 	struct fuse_arg args[3];
 };
 
-struct fuse_req;
-struct fuse_conn;
-
 /**
  * A request to the client
  */