Re: [TOMOYO #5 02/18] Add wrapper functions for VFS helper functions.
Hello.
Christoph Hellwig wrote:
> > NACK to this. Passing function parameters through the task_struct is
> > definitely not an acceptable hack
> Exactly. Having a vfsmount other than the current processes root or
> current working directory in task_struct doesn't make any sense.
The process's root and cwd vfsmounts are used permanently, but
this last_vfsmount passed via task_struct behaves like temporary variable
pushed on stack memory.
In other words, last_vfsmount becomes NULL when it becomes invalid.
| static inline int vfs_create2(struct inode *dir, struct dentry *dentry,
| int mode, struct nameidata *nd)
| {
| int ret;
| struct vfsmount *mnt = nd ? nd->path.mnt : NULL;
| struct task_struct *task = current;
| struct vfsmount *prev_mnt = task->last_vfsmount;
| task->last_vfsmount = mntget(mnt);
| ret = vfs_create(dir, dentry, mode, nd);
| task->last_vfsmount = prev_mnt;
| mntput(mnt);
| return ret;
| }
I agree that keeping last_vfsmount after it lost it's reference count is bad,
but
I don't understand why keeping last_vfsmount while it has it's reference count
is bad too.
Regards.
-
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Re: [TOMOYO #5 02/18] Add wrapper functions for VFS helper functions.
On Fri, Nov 16, 2007 at 12:47:35PM -0500, Trond Myklebust wrote: > > On Sat, 2007-11-17 at 02:34 +0900, [EMAIL PROTECTED] > wrote: > > plain text document attachment > > (add-wrapper-functions-for-vfs-helper-functions.patch) > > This patch allows LSM hooks refer previously associated "struct vfsmount" > > parameter > > so that they can calculate pathname of given "struct dentry". > > NACK to this. Passing function parameters through the task_struct is > definitely not an acceptable hack Exactly. Having a vfsmount other than the current processes root or current working directory in task_struct doesn't make any sense. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [TOMOYO #5 02/18] Add wrapper functions for VFS helper functions.
On Fri, Nov 16, 2007 at 12:47:35PM -0500, Trond Myklebust wrote: On Sat, 2007-11-17 at 02:34 +0900, [EMAIL PROTECTED] wrote: plain text document attachment (add-wrapper-functions-for-vfs-helper-functions.patch) This patch allows LSM hooks refer previously associated struct vfsmount parameter so that they can calculate pathname of given struct dentry. NACK to this. Passing function parameters through the task_struct is definitely not an acceptable hack Exactly. Having a vfsmount other than the current processes root or current working directory in task_struct doesn't make any sense. - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [TOMOYO #5 02/18] Add wrapper functions for VFS helper functions.
Hello.
Christoph Hellwig wrote:
NACK to this. Passing function parameters through the task_struct is
definitely not an acceptable hack
Exactly. Having a vfsmount other than the current processes root or
current working directory in task_struct doesn't make any sense.
The process's root and cwd vfsmounts are used permanently, but
this last_vfsmount passed via task_struct behaves like temporary variable
pushed on stack memory.
In other words, last_vfsmount becomes NULL when it becomes invalid.
| static inline int vfs_create2(struct inode *dir, struct dentry *dentry,
| int mode, struct nameidata *nd)
| {
| int ret;
| struct vfsmount *mnt = nd ? nd-path.mnt : NULL;
| struct task_struct *task = current;
| struct vfsmount *prev_mnt = task-last_vfsmount;
| task-last_vfsmount = mntget(mnt);
| ret = vfs_create(dir, dentry, mode, nd);
| task-last_vfsmount = prev_mnt;
| mntput(mnt);
| return ret;
| }
I agree that keeping last_vfsmount after it lost it's reference count is bad,
but
I don't understand why keeping last_vfsmount while it has it's reference count
is bad too.
Regards.
-
To unsubscribe from this list: send the line unsubscribe linux-kernel in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Re: [TOMOYO #5 02/18] Add wrapper functions for VFS helper functions.
On Sat, 2007-11-17 at 02:34 +0900, [EMAIL PROTECTED] wrote: > plain text document attachment > (add-wrapper-functions-for-vfs-helper-functions.patch) > This patch allows LSM hooks refer previously associated "struct vfsmount" > parameter > so that they can calculate pathname of given "struct dentry". NACK to this. Passing function parameters through the task_struct is definitely not an acceptable hack (unless you're doing it through the stack). Trond - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
[TOMOYO #5 02/18] Add wrapper functions for VFS helper functions.
This patch allows LSM hooks refer previously associated "struct vfsmount"
parameter
so that they can calculate pathname of given "struct dentry".
Signed-off-by: Tetsuo Handa <[EMAIL PROTECTED]>
---
include/linux/fs.h | 138 +
1 file changed, 138 insertions(+)
--- linux-2.6-mm.orig/include/linux/fs.h2007-11-14 15:14:52.0
+0900
+++ linux-2.6-mm/include/linux/fs.h 2007-11-14 15:20:32.0 +0900
@@ -1086,6 +1086,116 @@ extern int vfs_rmdir(struct inode *, str
extern int vfs_unlink(struct inode *, struct dentry *);
extern int vfs_rename(struct inode *, struct dentry *, struct inode *, struct
dentry *);
+#include
+#include
+
+static inline int vfs_create2(struct inode *dir, struct dentry *dentry,
+ int mode, struct nameidata *nd)
+{
+ int ret;
+ struct vfsmount *mnt = nd ? nd->path.mnt : NULL;
+ struct task_struct *task = current;
+ struct vfsmount *prev_mnt = task->last_vfsmount;
+ task->last_vfsmount = mntget(mnt);
+ ret = vfs_create(dir, dentry, mode, nd);
+ task->last_vfsmount = prev_mnt;
+ mntput(mnt);
+ return ret;
+}
+
+static inline int vfs_mkdir2(struct inode *dir, struct dentry *dentry,
+struct vfsmount *mnt, int mode)
+{
+ int ret;
+ struct task_struct *task = current;
+ struct vfsmount *prev_mnt = task->last_vfsmount;
+ task->last_vfsmount = mntget(mnt);
+ ret = vfs_mkdir(dir, dentry, mode);
+ task->last_vfsmount = prev_mnt;
+ mntput(mnt);
+ return ret;
+}
+
+static inline int vfs_mknod2(struct inode *dir, struct dentry *dentry,
+struct vfsmount *mnt, int mode, dev_t dev)
+{
+ int ret;
+ struct task_struct *task = current;
+ struct vfsmount *prev_mnt = task->last_vfsmount;
+ task->last_vfsmount = mntget(mnt);
+ ret = vfs_mknod(dir, dentry, mode, dev);
+ task->last_vfsmount = prev_mnt;
+ mntput(mnt);
+ return ret;
+}
+
+static inline int vfs_symlink2(struct inode *dir, struct dentry *dentry,
+ struct vfsmount *mnt, const char *oldname,
+ int mode)
+{
+ int ret;
+ struct task_struct *task = current;
+ struct vfsmount *prev_mnt = task->last_vfsmount;
+ task->last_vfsmount = mntget(mnt);
+ ret = vfs_symlink(dir, dentry, oldname, mode);
+ task->last_vfsmount = prev_mnt;
+ mntput(mnt);
+ return ret;
+}
+
+static inline int vfs_link2(struct dentry *old_dentry, struct inode *dir,
+ struct dentry *new_dentry, struct vfsmount *mnt)
+{
+ int ret;
+ struct task_struct *task = current;
+ struct vfsmount *prev_mnt = task->last_vfsmount;
+ task->last_vfsmount = mntget(mnt);
+ ret = vfs_link(old_dentry, dir, new_dentry);
+ task->last_vfsmount = prev_mnt;
+ mntput(mnt);
+ return ret;
+}
+
+static inline int vfs_rmdir2(struct inode *dir, struct dentry *dentry,
+struct vfsmount *mnt)
+{
+ int ret;
+ struct task_struct *task = current;
+ struct vfsmount *prev_mnt = task->last_vfsmount;
+ task->last_vfsmount = mntget(mnt);
+ ret = vfs_rmdir(dir, dentry);
+ task->last_vfsmount = prev_mnt;
+ mntput(mnt);
+ return ret;
+}
+
+static inline int vfs_unlink2(struct inode *dir, struct dentry *dentry,
+struct vfsmount *mnt)
+{
+ int ret;
+ struct task_struct *task = current;
+ struct vfsmount *prev_mnt = task->last_vfsmount;
+ task->last_vfsmount = mntget(mnt);
+ ret = vfs_unlink(dir, dentry);
+ task->last_vfsmount = prev_mnt;
+ mntput(mnt);
+ return ret;
+}
+
+static inline int vfs_rename2(struct inode *old_dir, struct dentry *old_dentry,
+ struct inode *new_dir, struct dentry *new_dentry,
+ struct vfsmount *mnt)
+{
+ int ret;
+ struct task_struct *task = current;
+ struct vfsmount *prev_mnt = task->last_vfsmount;
+ task->last_vfsmount = mntget(mnt);
+ ret = vfs_rename(old_dir, old_dentry, new_dir, new_dentry);
+ task->last_vfsmount = prev_mnt;
+ mntput(mnt);
+ return ret;
+}
+
/*
* VFS dentry helper functions.
*/
@@ -1548,6 +1658,21 @@ static inline int break_lease(struct ino
extern int do_truncate(struct dentry *, loff_t start, unsigned int time_attrs,
struct file *filp);
+
+static inline int do_truncate2(struct dentry *dentry, struct vfsmount *mnt,
+ loff_t length, unsigned int time_attrs,
+ struct file *filp)
+{
+ int ret;
+ struct task_struct *task = current;
+ struct vfsmount *prev_mnt = task->last_vfsmount;
+ task->last_vfsmount = mntget(mnt);
+ ret =
[TOMOYO #5 02/18] Add wrapper functions for VFS helper functions.
This patch allows LSM hooks refer previously associated struct vfsmount
parameter
so that they can calculate pathname of given struct dentry.
Signed-off-by: Tetsuo Handa [EMAIL PROTECTED]
---
include/linux/fs.h | 138 +
1 file changed, 138 insertions(+)
--- linux-2.6-mm.orig/include/linux/fs.h2007-11-14 15:14:52.0
+0900
+++ linux-2.6-mm/include/linux/fs.h 2007-11-14 15:20:32.0 +0900
@@ -1086,6 +1086,116 @@ extern int vfs_rmdir(struct inode *, str
extern int vfs_unlink(struct inode *, struct dentry *);
extern int vfs_rename(struct inode *, struct dentry *, struct inode *, struct
dentry *);
+#include linux/mount.h
+#include linux/sched.h
+
+static inline int vfs_create2(struct inode *dir, struct dentry *dentry,
+ int mode, struct nameidata *nd)
+{
+ int ret;
+ struct vfsmount *mnt = nd ? nd-path.mnt : NULL;
+ struct task_struct *task = current;
+ struct vfsmount *prev_mnt = task-last_vfsmount;
+ task-last_vfsmount = mntget(mnt);
+ ret = vfs_create(dir, dentry, mode, nd);
+ task-last_vfsmount = prev_mnt;
+ mntput(mnt);
+ return ret;
+}
+
+static inline int vfs_mkdir2(struct inode *dir, struct dentry *dentry,
+struct vfsmount *mnt, int mode)
+{
+ int ret;
+ struct task_struct *task = current;
+ struct vfsmount *prev_mnt = task-last_vfsmount;
+ task-last_vfsmount = mntget(mnt);
+ ret = vfs_mkdir(dir, dentry, mode);
+ task-last_vfsmount = prev_mnt;
+ mntput(mnt);
+ return ret;
+}
+
+static inline int vfs_mknod2(struct inode *dir, struct dentry *dentry,
+struct vfsmount *mnt, int mode, dev_t dev)
+{
+ int ret;
+ struct task_struct *task = current;
+ struct vfsmount *prev_mnt = task-last_vfsmount;
+ task-last_vfsmount = mntget(mnt);
+ ret = vfs_mknod(dir, dentry, mode, dev);
+ task-last_vfsmount = prev_mnt;
+ mntput(mnt);
+ return ret;
+}
+
+static inline int vfs_symlink2(struct inode *dir, struct dentry *dentry,
+ struct vfsmount *mnt, const char *oldname,
+ int mode)
+{
+ int ret;
+ struct task_struct *task = current;
+ struct vfsmount *prev_mnt = task-last_vfsmount;
+ task-last_vfsmount = mntget(mnt);
+ ret = vfs_symlink(dir, dentry, oldname, mode);
+ task-last_vfsmount = prev_mnt;
+ mntput(mnt);
+ return ret;
+}
+
+static inline int vfs_link2(struct dentry *old_dentry, struct inode *dir,
+ struct dentry *new_dentry, struct vfsmount *mnt)
+{
+ int ret;
+ struct task_struct *task = current;
+ struct vfsmount *prev_mnt = task-last_vfsmount;
+ task-last_vfsmount = mntget(mnt);
+ ret = vfs_link(old_dentry, dir, new_dentry);
+ task-last_vfsmount = prev_mnt;
+ mntput(mnt);
+ return ret;
+}
+
+static inline int vfs_rmdir2(struct inode *dir, struct dentry *dentry,
+struct vfsmount *mnt)
+{
+ int ret;
+ struct task_struct *task = current;
+ struct vfsmount *prev_mnt = task-last_vfsmount;
+ task-last_vfsmount = mntget(mnt);
+ ret = vfs_rmdir(dir, dentry);
+ task-last_vfsmount = prev_mnt;
+ mntput(mnt);
+ return ret;
+}
+
+static inline int vfs_unlink2(struct inode *dir, struct dentry *dentry,
+struct vfsmount *mnt)
+{
+ int ret;
+ struct task_struct *task = current;
+ struct vfsmount *prev_mnt = task-last_vfsmount;
+ task-last_vfsmount = mntget(mnt);
+ ret = vfs_unlink(dir, dentry);
+ task-last_vfsmount = prev_mnt;
+ mntput(mnt);
+ return ret;
+}
+
+static inline int vfs_rename2(struct inode *old_dir, struct dentry *old_dentry,
+ struct inode *new_dir, struct dentry *new_dentry,
+ struct vfsmount *mnt)
+{
+ int ret;
+ struct task_struct *task = current;
+ struct vfsmount *prev_mnt = task-last_vfsmount;
+ task-last_vfsmount = mntget(mnt);
+ ret = vfs_rename(old_dir, old_dentry, new_dir, new_dentry);
+ task-last_vfsmount = prev_mnt;
+ mntput(mnt);
+ return ret;
+}
+
/*
* VFS dentry helper functions.
*/
@@ -1548,6 +1658,21 @@ static inline int break_lease(struct ino
extern int do_truncate(struct dentry *, loff_t start, unsigned int time_attrs,
struct file *filp);
+
+static inline int do_truncate2(struct dentry *dentry, struct vfsmount *mnt,
+ loff_t length, unsigned int time_attrs,
+ struct file *filp)
+{
+ int ret;
+ struct task_struct *task = current;
+ struct vfsmount *prev_mnt = task-last_vfsmount;
+ task-last_vfsmount = mntget(mnt);
+ ret =
Re: [TOMOYO #5 02/18] Add wrapper functions for VFS helper functions.
On Sat, 2007-11-17 at 02:34 +0900, [EMAIL PROTECTED] wrote: plain text document attachment (add-wrapper-functions-for-vfs-helper-functions.patch) This patch allows LSM hooks refer previously associated struct vfsmount parameter so that they can calculate pathname of given struct dentry. NACK to this. Passing function parameters through the task_struct is definitely not an acceptable hack (unless you're doing it through the stack). Trond - To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
