[AppArmor 33/47] VFS: new fsetattr() file operation

From: John
Date: Thu Dec 20 2007 - 09:27:37 EST

From: Miklos Szeredi <mszeredi@xxxxxxx>

Add a new file operation: f_op->fsetattr(), that is invoked by
ftruncate, fchmod, fchown and utimensat. Fall back to i_op->setattr()
if it is not defined.

For the reasons why we need this, see patch adding fgetattr().

ftruncate() already passed the open file to the filesystem via the
ia_file member of struct iattr. However it is cleaner to have a
separate file operation for this, so remove ia_file and convert
existing users: fuse, AFS, and reiserfs4. Use ATTR_FILE to allow
LSMs to distinguish file descriptor based operations.

Signed-off-by: Miklos Szeredi <mszeredi@xxxxxxx>
Signed-off-by: John Johansen <jjohansen@xxxxxxx>

---
fs/afs/dir.c | 1 +
fs/afs/file.c | 1 +
fs/afs/inode.c | 19 +++++++++++++++----
fs/afs/internal.h | 1 +
fs/attr.c | 18 ++++++++++++++----
fs/fuse/dir.c | 20 +++++++++-----------
fs/fuse/file.c | 7 +++++++
fs/fuse/fuse_i.h | 4 ++++
fs/open.c | 25 +++++++++++++------------
fs/reiser4/plugin/file/cryptcompress.c | 12 +++++++++++-
fs/reiser4/plugin/file/file.c | 27 ++++++++++++++++++++-------
fs/reiser4/plugin/file/file.h | 3 +++
fs/reiser4/plugin/file/file_conversion.c | 7 +++++++
fs/reiser4/plugin/object.c | 5 ++++-
fs/reiser4/plugin/plugin.h | 1 +
fs/utimes.c | 2 +-
include/linux/fs.h | 9 ++-------
17 files changed, 114 insertions(+), 48 deletions(-)

--- a/fs/afs/dir.c
+++ b/fs/afs/dir.c
@@ -45,6 +45,7 @@ const struct file_operations afs_dir_fil
.release = afs_release,
.readdir = afs_readdir,
.lock = afs_lock,
+ .fsetattr = afs_fsetattr,
};

const struct inode_operations afs_dir_inode_operations = {
--- a/fs/afs/file.c
+++ b/fs/afs/file.c
@@ -36,6 +36,7 @@ const struct file_operations afs_file_op
.fsync = afs_fsync,
.lock = afs_lock,
.flock = afs_flock,
+ .fsetattr = afs_fsetattr,
};

const struct inode_operations afs_file_inode_operations = {
--- a/fs/afs/inode.c
+++ b/fs/afs/inode.c
@@ -358,7 +358,8 @@ void afs_clear_inode(struct inode *inode
/*
* set the attributes of an inode
*/
-int afs_setattr(struct dentry *dentry, struct iattr *attr)
+static int afs_do_setattr(struct dentry *dentry, struct iattr *attr,
+ struct file *file)
{
struct afs_vnode *vnode = AFS_FS_I(dentry->d_inode);
struct key *key;
@@ -380,8 +381,8 @@ int afs_setattr(struct dentry *dentry, s
afs_writeback_all(vnode);
}

- if (attr->ia_valid & ATTR_FILE) {
- key = attr->ia_file->private_data;
+ if (file) {
+ key = file->private_data;
} else {
key = afs_request_key(vnode->volume->cell);
if (IS_ERR(key)) {
@@ -391,10 +392,20 @@ int afs_setattr(struct dentry *dentry, s
}

ret = afs_vnode_setattr(vnode, key, attr);
- if (!(attr->ia_valid & ATTR_FILE))
+ if (!file)
key_put(key);

error:
_leave(" = %d", ret);
return ret;
}
+
+int afs_setattr(struct dentry *dentry, struct iattr *attr)
+{
+ return afs_do_setattr(dentry, attr, NULL);
+}
+
+int afs_fsetattr(struct file *file, struct iattr *attr)
+{
+ return afs_do_setattr(file->f_path.dentry, attr, file);
+}
--- a/fs/afs/internal.h
+++ b/fs/afs/internal.h
@@ -550,6 +550,7 @@ extern void afs_zap_data(struct afs_vnod
extern int afs_validate(struct afs_vnode *, struct key *);
extern int afs_getattr(struct vfsmount *, struct dentry *, struct kstat *);
extern int afs_setattr(struct dentry *, struct iattr *);
+extern int afs_fsetattr(struct file *, struct iattr *);
extern void afs_clear_inode(struct inode *);

/*
--- a/fs/attr.c
+++ b/fs/attr.c
@@ -100,8 +100,8 @@ int inode_setattr(struct inode * inode,
}
EXPORT_SYMBOL(inode_setattr);

-int notify_change(struct dentry *dentry, struct vfsmount *mnt,
- struct iattr *attr)
+int fnotify_change(struct dentry *dentry, struct vfsmount *mnt,
+ struct iattr *attr, struct file *file)
{
struct inode *inode = dentry->d_inode;
mode_t mode = inode->i_mode;
@@ -160,8 +160,12 @@ int notify_change(struct dentry *dentry,

if (inode->i_op && inode->i_op->setattr) {
error = security_inode_setattr(dentry, mnt, attr);
- if (!error)
- error = inode->i_op->setattr(dentry, attr);
+ if (!error) {
+ if (file && file->f_op && file->f_op->fsetattr)
+ error = file->f_op->fsetattr(file, attr);
+ else
+ error = inode->i_op->setattr(dentry, attr);
+ }
} else {
error = inode_change_ok(inode, attr);
if (!error)
@@ -184,4 +188,10 @@ int notify_change(struct dentry *dentry,
return error;
}

+int notify_change(struct dentry *dentry, struct vfsmount *mnt,
+ struct iattr *attr)
+{
+ return fnotify_change(dentry, mnt, attr, NULL);
+}
+
EXPORT_SYMBOL(notify_change);
--- a/fs/fuse/dir.c
+++ b/fs/fuse/dir.c
@@ -1063,21 +1063,22 @@ static int fuse_dir_fsync(struct file *f
return file ? fuse_fsync_common(file, de, datasync, 1) : 0;
}

-static bool update_mtime(unsigned ivalid)
+static bool update_mtime(unsigned ivalid, bool have_file)
{
/* Always update if mtime is explicitly set */
if (ivalid & ATTR_MTIME_SET)
return true;

/* If it's an open(O_TRUNC) or an ftruncate(), don't update */
- if ((ivalid & ATTR_SIZE) && (ivalid & (ATTR_OPEN | ATTR_FILE)))
+ if ((ivalid & ATTR_SIZE) && ((ivalid & ATTR_OPEN) || have_file))
return false;

/* In all other cases update */
return true;
}

-static void iattr_to_fattr(struct iattr *iattr, struct fuse_setattr_in *arg)
+static void iattr_to_fattr(struct iattr *iattr, struct fuse_setattr_in *arg,
+ bool have_file)
{
unsigned ivalid = iattr->ia_valid;

@@ -1096,7 +1097,7 @@ static void iattr_to_fattr(struct iattr
if (!(ivalid & ATTR_ATIME_SET))
arg->valid |= FATTR_ATIME_NOW;
}
- if ((ivalid & ATTR_MTIME) && update_mtime(ivalid)) {
+ if ((ivalid & ATTR_MTIME) && update_mtime(ivalid, have_file)) {
arg->valid |= FATTR_MTIME;
arg->mtime = iattr->ia_mtime.tv_sec;
arg->mtimensec = iattr->ia_mtime.tv_nsec;
@@ -1113,8 +1114,8 @@ static void iattr_to_fattr(struct iattr
* vmtruncate() doesn't allow for this case, so do the rlimit checking
* and the actual truncation by hand.
*/
-static int fuse_do_setattr(struct dentry *entry, struct iattr *attr,
- struct file *file)
+int fuse_do_setattr(struct dentry *entry, struct iattr *attr,
+ struct file *file)
{
struct inode *inode = entry->d_inode;
struct fuse_conn *fc = get_fuse_conn(inode);
@@ -1152,7 +1153,7 @@ static int fuse_do_setattr(struct dentry

memset(&inarg, 0, sizeof(inarg));
memset(&outarg, 0, sizeof(outarg));
- iattr_to_fattr(attr, &inarg);
+ iattr_to_fattr(attr, &inarg, file != NULL);
if (file) {
struct fuse_file *ff = file->private_data;
inarg.valid |= FATTR_FH;
@@ -1194,10 +1195,7 @@ static int fuse_do_setattr(struct dentry

static int fuse_setattr(struct dentry *entry, struct iattr *attr)
{
- if (attr->ia_valid & ATTR_FILE)
- return fuse_do_setattr(entry, attr, attr->ia_file);
- else
- return fuse_do_setattr(entry, attr, NULL);
+ return fuse_do_setattr(entry, attr, NULL);
}

static int fuse_getattr(struct vfsmount *mnt, struct dentry *entry,
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -918,6 +918,11 @@ static sector_t fuse_bmap(struct address
return err ? 0 : outarg.block;
}

+static int fuse_fsetattr(struct file *file, struct iattr *attr)
+{
+ return fuse_do_setattr(file->f_path.dentry, attr, file);
+}
+
static const struct file_operations fuse_file_operations = {
.llseek = generic_file_llseek,
.read = do_sync_read,
@@ -932,6 +937,7 @@ static const struct file_operations fuse
.lock = fuse_file_lock,
.flock = fuse_file_flock,
.fgetattr = fuse_file_fgetattr,
+ .fsetattr = fuse_fsetattr,
.splice_read = generic_file_splice_read,
};

@@ -946,6 +952,7 @@ static const struct file_operations fuse
.lock = fuse_file_lock,
.flock = fuse_file_flock,
.fgetattr = fuse_file_fgetattr,
+ .fsetattr = fuse_fsetattr,
/* no mmap and splice_read */
};

--- a/fs/fuse/fuse_i.h
+++ b/fs/fuse/fuse_i.h
@@ -505,6 +505,10 @@ void fuse_change_attributes(struct inode
*/
int fuse_dev_init(void);

+
+int fuse_do_setattr(struct dentry *entry, struct iattr *attr,
+ struct file *file);
+
/**
* Cleanup the client device
*/
--- a/fs/open.c
+++ b/fs/open.c
@@ -206,16 +206,15 @@ int do_truncate(struct dentry *dentry, s

newattrs.ia_size = length;
newattrs.ia_valid = ATTR_SIZE | time_attrs;
- if (filp) {
- newattrs.ia_file = filp;
+
+ if (filp)
newattrs.ia_valid |= ATTR_FILE;
- }

/* Remove suid/sgid on truncate too */
newattrs.ia_valid |= should_remove_suid(dentry);

mutex_lock(&dentry->d_inode->i_mutex);
- err = notify_change(dentry, mnt, &newattrs);
+ err = fnotify_change(dentry, mnt, &newattrs, filp);
mutex_unlock(&dentry->d_inode->i_mutex);
return err;
}
@@ -590,8 +589,8 @@ asmlinkage long sys_fchmod(unsigned int
if (mode == (mode_t) -1)
mode = inode->i_mode;
newattrs.ia_mode = (mode & S_IALLUGO) | (inode->i_mode & ~S_IALLUGO);
- newattrs.ia_valid = ATTR_MODE | ATTR_CTIME;
- err = notify_change(dentry, file->f_path.mnt, &newattrs);
+ newattrs.ia_valid = ATTR_MODE | ATTR_CTIME | ATTR_FILE;
+ err = fnotify_change(dentry, file->f_path.mnt, &newattrs, file);
mutex_unlock(&inode->i_mutex);

out_drop_write:
@@ -645,7 +644,7 @@ asmlinkage long sys_chmod(const char __u
}

static int chown_common(struct dentry * dentry, struct vfsmount *mnt,
- uid_t user, gid_t group)
+ uid_t user, gid_t group, struct file *file)
{
struct inode * inode;
int error;
@@ -671,8 +670,10 @@ static int chown_common(struct dentry *
if (!S_ISDIR(inode->i_mode))
newattrs.ia_valid |=
ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_KILL_PRIV;
+ if (file)
+ newattrs.ia_valid |= ATTR_FILE;
mutex_lock(&inode->i_mutex);
- error = notify_change(dentry, mnt, &newattrs);
+ error = fnotify_change(dentry, mnt, &newattrs, file);
mutex_unlock(&inode->i_mutex);
out:
return error;
@@ -689,7 +690,7 @@ asmlinkage long sys_chown(const char __u
error = mnt_want_write(nd.path.mnt);
if (error)
goto out_release;
- error = chown_common(nd.path.dentry, nd.path.mnt, user, group);
+ error = chown_common(nd.path.dentry, nd.path.mnt, user, group, NULL);
mnt_drop_write(nd.path.mnt);
out_release:
path_put(&nd.path);
@@ -714,7 +715,7 @@ asmlinkage long sys_fchownat(int dfd, co
error = mnt_want_write(nd.path.mnt);
if (error)
goto out_release;
- error = chown_common(nd.path.dentry, nd.path.mnt, user, group);
+ error = chown_common(nd.path.dentry, nd.path.mnt, user, group, NULL);
mnt_drop_write(nd.path.mnt);
out_release:
path_put(&nd.path);
@@ -733,7 +734,7 @@ asmlinkage long sys_lchown(const char __
error = mnt_want_write(nd.path.mnt);
if (error)
goto out_release;
- error = chown_common(nd.path.dentry, nd.path.mnt, user, group);
+ error = chown_common(nd.path.dentry, nd.path.mnt, user, group, NULL);
mnt_drop_write(nd.path.mnt);
out_release:
path_put(&nd.path);
@@ -757,7 +758,7 @@ asmlinkage long sys_fchown(unsigned int
goto out_fput;
dentry = file->f_path.dentry;
audit_inode(NULL, dentry);
- error = chown_common(dentry, file->f_path.mnt, user, group);
+ error = chown_common(dentry, file->f_path.mnt, user, group, file);
mnt_drop_write(file->f_vfsmnt);
out_fput:
fput(file);
--- a/fs/reiser4/plugin/file/cryptcompress.c
+++ b/fs/reiser4/plugin/file/cryptcompress.c
@@ -3688,7 +3688,7 @@ int delete_object_cryptcompress(struct i
* plugin->setattr
* This implements actual truncate (see comments in reiser4/page_cache.c)
*/
-int setattr_cryptcompress(struct dentry *dentry, struct iattr *attr)
+static int do_setattr_cryptcompress(struct dentry *dentry, struct iattr *attr)
{
int result;
struct inode *inode;
@@ -3731,6 +3731,16 @@ int setattr_cryptcompress(struct dentry
return result;
}

+int setattr_cryptcompress(struct dentry *dentry, struct iattr *attr)
+{
+ return do_setattr_cryptcompress(dentry, attr);
+}
+
+int fsetattr_cryptcompress(struct file *file, struct iattr *attr)
+{
+ return do_setattr_cryptcompress(file->f_path.dentry, attr);
+}
+
/* plugin->release */
int release_cryptcompress(struct inode *inode, struct file *file)
{
--- a/fs/reiser4/plugin/file/file.c
+++ b/fs/reiser4/plugin/file/file.c
@@ -561,19 +561,20 @@ static int should_have_notail(const stru
* truncate_file_body - change length of file
* @inode: inode of file
* @new_size: new file length
+ * @file: open file being truncated through foperation
*
* Adjusts items file @inode is built of to match @new_size. It may either cut
* items or add them to represent a hole at the end of file. The caller has to
* obtain exclusive access to the file.
*/
-static int truncate_file_body(struct inode *inode, struct iattr *attr)
+static int truncate_file_body(struct inode *inode, struct iattr *attr,
+ struct file *file)
{
int result;
loff_t new_size = attr->ia_size;

if (inode->i_size < new_size) {
/* expanding truncate */
- struct file * file = attr->ia_file;
struct unix_file_info *uf_info = unix_file_inode_data(inode);

assert("edward-1532", attr->ia_valid & ATTR_FILE);
@@ -2581,7 +2582,8 @@ owns_item_unix_file(const struct inode *
return 1;
}

-static int setattr_truncate(struct inode *inode, struct iattr *attr)
+static int setattr_truncate(struct inode *inode, struct iattr *attr,
+ struct file *file)
{
int result;
int s_result;
@@ -2597,7 +2599,7 @@ static int setattr_truncate(struct inode
if (result == 0)
result = safe_link_add(inode, SAFE_TRUNCATE);
if (result == 0)
- result = truncate_file_body(inode, attr);
+ result = truncate_file_body(inode, attr, file);
if (result)
warning("vs-1588", "truncate_file failed: oid %lli, "
"old size %lld, new size %lld, retval %d",
@@ -2619,8 +2621,9 @@ static int setattr_truncate(struct inode
/* plugin->u.file.setattr method */
/* This calls inode_setattr and if truncate is in effect it also takes
exclusive inode access to avoid races */
-int setattr_unix_file(struct dentry *dentry, /* Object to change attributes */
- struct iattr *attr /* change description */ )
+static int do_setattr_unix_file(struct dentry *dentry, /* Object to change attributes */
+ struct iattr *attr, /* change description */
+ struct file *file)
{
int result;

@@ -2636,7 +2639,7 @@ int setattr_unix_file(struct dentry *den

uf_info = unix_file_inode_data(dentry->d_inode);
get_exclusive_access_careful(uf_info, dentry->d_inode);
- result = setattr_truncate(dentry->d_inode, attr);
+ result = setattr_truncate(dentry->d_inode, attr, file);
drop_exclusive_access(uf_info);
context_set_commit_async(ctx);
reiser4_exit_context(ctx);
@@ -2646,6 +2649,16 @@ int setattr_unix_file(struct dentry *den
return result;
}

+int setattr_unix_file(struct dentry *dentry, struct iattr *attr)
+{
+ return do_setattr_unix_file(dentry, attr, NULL);
+}
+
+int fsetattr_unix_file(struct file *file, struct iattr *attr)
+{
+ return do_setattr_unix_file(file->f_path.dentry, attr, file);
+}
+
/* plugin->u.file.init_inode_data */
void
init_inode_data_unix_file(struct inode *inode,
--- a/fs/reiser4/plugin/file/file.h
+++ b/fs/reiser4/plugin/file/file.h
@@ -39,6 +39,7 @@ int reiser4_mmap_careful(struct file *,
int reiser4_open_careful(struct inode *inode, struct file *file);
int reiser4_release_careful(struct inode *, struct file *);
int reiser4_sync_file_common(struct file *, struct dentry *, int datasync);
+int reiser4_fsetattr_careful(struct file *file, struct iattr *attr);

/* address space operations */
int reiser4_readpage(struct file *, struct page *);
@@ -70,6 +71,7 @@ int ioctl_unix_file(struct inode *, stru
int mmap_unix_file(struct file *, struct vm_area_struct *);
int open_unix_file(struct inode *, struct file *);
int release_unix_file(struct inode *, struct file *);
+int fsetattr_unix_file(struct file *, struct iattr *);

/* private address space operations */
int readpage_unix_file(struct file *, struct page *);
@@ -107,6 +109,7 @@ int ioctl_cryptcompress(struct inode *,
int mmap_cryptcompress(struct file *, struct vm_area_struct *);
int open_cryptcompress(struct inode *, struct file *);
int release_cryptcompress(struct inode *, struct file *);
+int fsetattr_cryptcompress(struct file *file, struct iattr *attr);

/* private address space operations */
int readpage_cryptcompress(struct file *, struct page *);
--- a/fs/reiser4/plugin/file/file_conversion.c
+++ b/fs/reiser4/plugin/file/file_conversion.c
@@ -602,6 +602,13 @@ int reiser4_setattr_careful(struct dentr
setattr_conversion_hook(inode, attr));
}

+int reiser4_fsetattr_careful(struct file *file, struct iattr *attr)
+{
+ struct inode * inode = file->f_path.dentry->d_inode;
+ return PROT_ACTIVE(int, fsetattr, (file, attr),
+ setattr_conversion_hook(inode, attr));
+}
+
/* Wrappers with passive protection for:
*
* ->open();
--- a/fs/reiser4/plugin/object.c
+++ b/fs/reiser4/plugin/object.c
@@ -105,7 +105,8 @@ static struct file_operations regular_fi
.release = reiser4_release_careful,
.fsync = reiser4_sync_file_common,
.splice_read = generic_file_splice_read,
- .splice_write = generic_file_splice_write
+ .splice_write = generic_file_splice_write,
+ .fsetattr = reiser4_fsetattr_careful
};
static struct address_space_operations regular_file_a_ops = {
.writepage = reiser4_writepage,
@@ -211,6 +212,7 @@ file_plugin file_plugins[LAST_FILE_PLUGI
.writepages = writepages_unix_file,
.prepare_write = prepare_write_unix_file,
.commit_write = commit_write_unix_file,
+ .fsetattr = fsetattr_unix_file,
/*
* private a_ops
*/
@@ -405,6 +407,7 @@ file_plugin file_plugins[LAST_FILE_PLUGI
.writepages = writepages_cryptcompress,
.prepare_write = prepare_write_cryptcompress,
.commit_write = commit_write_cryptcompress,
+ .fsetattr = fsetattr_cryptcompress,

.bmap = bmap_cryptcompress,

--- a/fs/reiser4/plugin/plugin.h
+++ b/fs/reiser4/plugin/plugin.h
@@ -237,6 +237,7 @@ typedef struct file_plugin {
unsigned int cmd, unsigned long arg);
int (*mmap) (struct file *, struct vm_area_struct *);
int (*release) (struct inode *, struct file *);
+ int (*fsetattr)(struct file *, struct iattr *);
/*
* private a_ops
*/
--- a/fs/utimes.c
+++ b/fs/utimes.c
@@ -135,7 +135,7 @@ long do_utimes(int dfd, char __user *fil
}
}
mutex_lock(&inode->i_mutex);
- error = notify_change(path.dentry, path.mnt, &newattrs);
+ error = fnotify_change(path.dentry, path.mnt, &newattrs, f);
mutex_unlock(&inode->i_mutex);
mnt_drop_write_and_out:
mnt_drop_write(path.mnt);
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -351,13 +351,6 @@ struct iattr {
struct timespec ia_atime;
struct timespec ia_mtime;
struct timespec ia_ctime;
-
- /*
- * Not an attribute, but an auxilary info for filesystems wanting to
- * implement an ftruncate() like method. NOTE: filesystem should
- * check for (ia_valid & ATTR_FILE), and not for (ia_file != NULL).
- */
- struct file *ia_file;
};

/*
@@ -1191,6 +1184,7 @@ struct file_operations {
ssize_t (*splice_read)(struct file *, loff_t *, struct pipe_inode_info *, size_t, unsigned int);
int (*setlease)(struct file *, long, struct file_lock **);
int (*fgetattr)(struct file *, struct kstat *);
+ int (*fsetattr)(struct file *, struct iattr *);
};

struct inode_operations {
@@ -1697,6 +1691,7 @@ extern int do_remount_sb(struct super_bl
extern sector_t bmap(struct inode *, sector_t);
#endif
extern int notify_change(struct dentry *, struct vfsmount *, struct iattr *);
+extern int fnotify_change(struct dentry *, struct vfsmount *, struct iattr *, struct file *);
extern int permission(struct inode *, int, struct nameidata *);
extern int generic_permission(struct inode *, int,
int (*check_acl)(struct inode *, int));

--

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