[patch 01/12] fuse: fix allowing operations

Miklos Szeredi
2007-10-02T15:52:48Z

[-- Attachment #1: fuse_allow_fixes.patch --]
[-- Type: text/plain, Size: 2389 bytes --]

From: Miklos Szeredi <mszeredi@suse.cz>

The following operation didn't check if sending the request was
allowed:

setattr
listxattr
statfs

Some other operations don't explicitly do the check, but VFS calls
->permission() which checks this.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
---

Index: linux/fs/fuse/dir.c
===================================================================
--- linux.orig/fs/fuse/dir.c 2007-09-25 21:19:00.000000000 +0200
+++ linux/fs/fuse/dir.c 2007-09-25 21:19:13.000000000 +0200
@@ -721,7 +721,7 @@ static int fuse_refresh_attributes(struc
* for which the owner of the mount has ptrace privilege. This
* excludes processes started by other users, suid or sgid processes.
*/
-static int fuse_allow_task(struct fuse_conn *fc, struct task_struct *task)
+int fuse_allow_task(struct fuse_conn *fc, struct task_struct *task)
{
if (fc->flags & FUSE_ALLOW_OTHER)
return 1;
@@ -1005,6 +1005,9 @@ static int fuse_setattr(struct dentry *e
struct fuse_attr_out outarg;
int err;

+ if (!fuse_allow_task(fc, current))
+ return -EACCES;
+
if (fc->flags & FUSE_DEFAULT_PERMISSIONS) {
err = inode_change_ok(inode, attr);
if (err)
@@ -1172,6 +1175,9 @@ static ssize_t fuse_listxattr(struct den
struct fuse_getxattr_out outarg;
ssize_t ret;

+ if (!fuse_allow_task(fc, current))
+ return -EACCES;
+
if (fc->no_listxattr)
return -EOPNOTSUPP;

Index: linux/fs/fuse/fuse_i.h
===================================================================
--- linux.orig/fs/fuse/fuse_i.h 2007-09-25 21:19:00.000000000 +0200
+++ linux/fs/fuse/fuse_i.h 2007-09-25 21:19:13.000000000 +0200
@@ -565,3 +565,8 @@ void fuse_ctl_remove_conn(struct fuse_co
* Is file type valid?
*/
int fuse_valid_type(int m);
+
+/**
+ * Is task allowed to perform filesystem operation?
+ */
+int fuse_allow_task(struct fuse_conn *fc, struct task_struct *task);
Index: linux/fs/fuse/inode.c
===================================================================
--- linux.orig/fs/fuse/inode.c 2007-09-25 21:19:00.000000000 +0200
+++ linux/fs/fuse/inode.c 2007-09-25 21:19:13.000000000 +0200
@@ -287,6 +287,11 @@ static int fuse_statfs(struct dentry *de
struct fuse_statfs_out outarg;
int err;

+ if (!fuse_allow_task(fc, current)) {
+ buf->f_type = FUSE_SUPER_MAGIC;
+ return 0;
+ }
+
req = fuse_get_req(fc);
if (IS_ERR(req))
return PTR_ERR(req);

--