From: Christoph Hellwig <hch@lst.de>
Currently it's up to the filesystem ->permission method to check whether
the filesystem is readonly or the file marked immutable. But this is
really a VFS decision, and the distintion becomes more important when
moving to per-mountpoint read only flags.
For most filesystems that have been using generic_permission this is not
change in behaviour. For those that we're missing the check (cifs without
CIFS_MOUNT_NO_PERM and coda [1]) this is a bugfix.
Both reiserfs and xfs have this check still in their ->permission routine
because they call it from other places aswell. I'll try switching them
over to generic_permission and will take care of this one.
[1] coda_ioctl_permission always returns 0, aka always grants access,
which looks more than fishy to me.
Signed-off-by: Andrew Morton <akpm@osdl.org>
---
25-akpm/fs/namei.c | 39 ++++++++++++++++++++-------------------
25-akpm/fs/nfs/dir.c | 18 ------------------
2 files changed, 20 insertions(+), 37 deletions(-)
diff -puN fs/namei.c~move-read-only-and-immutable-checks-into-permission fs/namei.c
--- 25/fs/namei.c~move-read-only-and-immutable-checks-into-permission Thu Jan 13 15:53:59 2005
+++ 25-akpm/fs/namei.c Thu Jan 13 15:53:59 2005
@@ -169,21 +169,6 @@ int generic_permission(struct inode *ino
{
umode_t mode = inode->i_mode;
- if (mask & MAY_WRITE) {
- /*
- * Nobody gets write access to a read-only fs.
- */
- if (IS_RDONLY(inode) &&
- (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode)))
- return -EROFS;
-
- /*
- * Nobody gets write access to an immutable file.
- */
- if (IS_IMMUTABLE(inode))
- return -EACCES;
- }
-
if (current->fsuid == inode->i_uid)
mode >>= 6;
else {
@@ -225,14 +210,30 @@ int generic_permission(struct inode *ino
return -EACCES;
}
-int permission(struct inode * inode,int mask, struct nameidata *nd)
+int permission(struct inode *inode, int mask, struct nameidata *nd)
{
- int retval;
- int submask;
+ int retval, submask;
+
+ if (mask & MAY_WRITE) {
+ umode_t mode = inode->i_mode;
+
+ /*
+ * Nobody gets write access to a read-only fs.
+ */
+ if (IS_RDONLY(inode) &&
+ (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode)))
+ return -EROFS;
+
+ /*
+ * Nobody gets write access to an immutable file.
+ */
+ if (IS_IMMUTABLE(inode))
+ return -EACCES;
+ }
+
/* Ordinary permission routines do not understand MAY_APPEND. */
submask = mask & ~MAY_APPEND;
-
if (inode->i_op && inode->i_op->permission)
retval = inode->i_op->permission(inode, submask, nd);
else
diff -puN fs/nfs/dir.c~move-read-only-and-immutable-checks-into-permission fs/nfs/dir.c
--- 25/fs/nfs/dir.c~move-read-only-and-immutable-checks-into-permission Thu Jan 13 15:53:59 2005
+++ 25-akpm/fs/nfs/dir.c Thu Jan 13 15:53:59 2005
@@ -1498,29 +1498,11 @@ out:
int nfs_permission(struct inode *inode, int mask, struct nameidata *nd)
{
struct rpc_cred *cred;
- int mode = inode->i_mode;
int res;
if (mask == 0)
return 0;
- if (mask & MAY_WRITE) {
- /*
- *
- * Nobody gets write access to a read-only fs.
- *
- */
- if (IS_RDONLY(inode) &&
- (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode)))
- return -EROFS;
- /*
- *
- * Nobody gets write access to an immutable file.
- *
- */
- if (IS_IMMUTABLE(inode))
- return -EACCES;
- }
/* Are we checking permissions on anything other than lookup/execute? */
if ((mask & MAY_EXEC) == 0) {
/* We only need to check permissions on file open() and access() */
_