From: Miklos Szeredi <[email protected]>
fuse_permission() didn't refresh inode attributes before using them,
even if the validity has already expired.
Thanks to Junjiro Okajima for spotting this.
Also remove some old code to unconditionally refresh the attributes on
the root inode.
Signed-off-by: Miklos Szeredi <[email protected]>
---
Index: linux/fs/fuse/dir.c
===================================================================
--- linux.orig/fs/fuse/dir.c 2007-08-03 18:36:01.000000000 +0200
+++ linux/fs/fuse/dir.c 2007-08-03 18:36:15.000000000 +0200
@@ -663,7 +663,7 @@ static int fuse_link(struct dentry *entr
return err;
}
-int fuse_do_getattr(struct inode *inode)
+static int fuse_do_getattr(struct inode *inode)
{
int err;
struct fuse_attr_out arg;
@@ -723,30 +723,6 @@ static int fuse_allow_task(struct fuse_c
return 0;
}
-/*
- * Check whether the inode attributes are still valid
- *
- * If the attribute validity timeout has expired, then fetch the fresh
- * attributes with a 'getattr' request
- *
- * I'm not sure why cached attributes are never returned for the root
- * inode, this is probably being too cautious.
- */
-static int fuse_revalidate(struct dentry *entry)
-{
- struct inode *inode = entry->d_inode;
- struct fuse_inode *fi = get_fuse_inode(inode);
- struct fuse_conn *fc = get_fuse_conn(inode);
-
- if (!fuse_allow_task(fc, current))
- return -EACCES;
- if (get_node_id(inode) != FUSE_ROOT_ID &&
- fi->i_time >= get_jiffies_64())
- return 0;
-
- return fuse_do_getattr(inode);
-}
-
static int fuse_access(struct inode *inode, int mask)
{
struct fuse_conn *fc = get_fuse_conn(inode);
@@ -794,16 +770,33 @@ static int fuse_access(struct inode *ino
static int fuse_permission(struct inode *inode, int mask, struct nameidata *nd)
{
struct fuse_conn *fc = get_fuse_conn(inode);
+ struct fuse_inode *fi = get_fuse_inode(inode);
+ bool refreshed = false;
+ int err = 0;
if (!fuse_allow_task(fc, current))
return -EACCES;
- else if (fc->flags & FUSE_DEFAULT_PERMISSIONS) {
+
+ /*
+ * If attributes are needed, but are stale, refresh them
+ * before proceeding
+ */
+ if (((fc->flags & FUSE_DEFAULT_PERMISSIONS) || (mask & MAY_EXEC)) &&
+ fi->i_time < get_jiffies_64()) {
+ err = fuse_do_getattr(inode);
+ if (err)
+ return err;
+
+ refreshed = true;
+ }
+
+ if (fc->flags & FUSE_DEFAULT_PERMISSIONS) {
int err = generic_permission(inode, mask, NULL);
/* If permission is denied, try to refresh file
attributes. This is also needed, because the root
node will at first have no permissions */
- if (err == -EACCES) {
+ if (err == -EACCES && !refreshed) {
err = fuse_do_getattr(inode);
if (!err)
err = generic_permission(inode, mask, NULL);
@@ -814,7 +807,6 @@ static int fuse_permission(struct inode
noticed immediately, only after the attribute
timeout has expired */
- return err;
} else {
int mode = inode->i_mode;
if ((mask & MAY_EXEC) && !S_ISDIR(mode) && !(mode & S_IXUGO))
@@ -822,8 +814,8 @@ static int fuse_permission(struct inode
if (nd && (nd->flags & (LOOKUP_ACCESS | LOOKUP_CHDIR)))
return fuse_access(inode, mask);
- return 0;
}
+ return err;
}
static int parse_dirfile(char *buf, size_t nbytes, struct file *file,
@@ -1052,7 +1044,16 @@ static int fuse_getattr(struct vfsmount
struct kstat *stat)
{
struct inode *inode = entry->d_inode;
- int err = fuse_revalidate(entry);
+ struct fuse_inode *fi = get_fuse_inode(inode);
+ struct fuse_conn *fc = get_fuse_conn(inode);
+ int err = 0;
+
+ if (!fuse_allow_task(fc, current))
+ return -EACCES;
+
+ if (fi->i_time < get_jiffies_64())
+ err = fuse_do_getattr(inode);
+
if (!err)
generic_fillattr(inode, stat);
Index: linux/fs/fuse/file.c
===================================================================
--- linux.orig/fs/fuse/file.c 2007-08-03 18:36:13.000000000 +0200
+++ linux/fs/fuse/file.c 2007-08-03 18:36:15.000000000 +0200
@@ -106,14 +106,6 @@ int fuse_open_common(struct inode *inode
if (err)
return err;
- /* If opening the root node, no lookup has been performed on
- it, so the attributes must be refreshed */
- if (get_node_id(inode) == FUSE_ROOT_ID) {
- err = fuse_do_getattr(inode);
- if (err)
- return err;
- }
-
ff = fuse_file_alloc();
if (!ff)
return -ENOMEM;
Index: linux/fs/fuse/fuse_i.h
===================================================================
--- linux.orig/fs/fuse/fuse_i.h 2007-08-03 18:36:05.000000000 +0200
+++ linux/fs/fuse/fuse_i.h 2007-08-03 18:36:15.000000000 +0200
@@ -533,11 +533,6 @@ void request_send_background(struct fuse
void fuse_abort_conn(struct fuse_conn *fc);
/**
- * Get the attributes of a file
- */
-int fuse_do_getattr(struct inode *inode);
-
-/**
* Invalidate inode attributes
*/
void fuse_invalidate_attr(struct inode *inode);
--
-
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