| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Date: Sat, 24 May 2008 13:04:48 +0900
From: Tetsuo Handa <penguin-kernel@...ove.SAKURA.ne.jp>
To: miklos@...redi.hu, linux-fsdevel@...r.kernel.org
Cc: hch@...radead.org, viro@...IV.linux.org.uk,
trond.myklebust@....uio.no, linux-kernel@...r.kernel.org
Subject: Re: [git patch] vfs: permission API cleanup (v2)
Hello.
I tried to insert a new LSM hook for truncate operation, but I had to insert
security_path_truncate() hook into multiple locations since do_truncate() is
directly called from some locations.
http://svn.sourceforge.jp/cgi-bin/viewcvs.cgi/*checkout*/trunk/2.2.x/tomoyo-lsm/patches/lsm-add-hooks-for-pathname-based-control.patch?rev=1244&root=tomoyo
Is it possible to replace do_truncate() and file_truncate() with path_truncate()
so that security_path_truncate() is called from only path_truncate()?
Regards.
----------
Subject: Replace do_truncate() and file_truncate() with path_truncate().
This patch replaces do_truncate() and file_truncate() with path_truncate().
Signed-off-by: Tetsuo Handa <penguin-kernel@...ove.SAKURA.ne.jp>
---
fs/exec.c | 2 +-
fs/namei.c | 14 +++++++-------
fs/open.c | 21 ++++++++++++---------
include/linux/fs.h | 6 ++----
mm/tiny-shmem.c | 2 +-
5 files changed, 23 insertions(+), 22 deletions(-)
--- vfs.orig/fs/exec.c
+++ vfs/fs/exec.c
@@ -1763,7 +1763,7 @@ int do_coredump(long signr, int exit_cod
goto close_fail;
if (!file->f_op->write)
goto close_fail;
- if (!ispipe && file_truncate(file, 0, 0) != 0)
+ if (!ispipe && path_truncate(&file->f_path, 0, 0, file) != 0)
goto close_fail;
retval = binfmt->core_dump(signr, regs, file, core_limit);
--- vfs.orig/fs/namei.c
+++ vfs/fs/namei.c
@@ -1626,8 +1626,8 @@ EXPORT_SYMBOL(path_create);
int may_open(struct nameidata *nd, int acc_mode, int flag)
{
int op;
- struct dentry *dentry = nd->path.dentry;
- struct inode *inode = dentry->d_inode;
+ struct path *path = &nd->path;
+ struct inode *inode = path->dentry->d_inode;
int error;
if (!inode)
@@ -1647,14 +1647,14 @@ int may_open(struct nameidata *nd, int a
if (S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) {
flag &= ~O_TRUNC;
} else if (S_ISBLK(inode->i_mode) || S_ISCHR(inode->i_mode)) {
- if (nd->path.mnt->mnt_flags & MNT_NODEV)
+ if (path->mnt->mnt_flags & MNT_NODEV)
return -EACCES;
flag &= ~O_TRUNC;
}
op = (nd->flags & LOOKUP_OPEN) ? PERM_OP_OPEN : 0;
- error = path_permission(&nd->path, acc_mode | op);
+ error = path_permission(path, acc_mode | op);
if (error)
return error;
/*
@@ -1691,9 +1691,9 @@ int may_open(struct nameidata *nd, int a
if (!error) {
DQUOT_INIT(inode);
- error = do_truncate(dentry, 0,
- ATTR_MTIME|ATTR_CTIME|ATTR_OPEN,
- NULL);
+ error = path_truncate(path, 0,
+ ATTR_MTIME|ATTR_CTIME|ATTR_OPEN,
+ NULL);
}
put_write_access(inode);
if (error)
--- vfs.orig/fs/open.c
+++ vfs/fs/open.c
@@ -200,10 +200,10 @@ out:
* @dentry: the dentry to truncate
* @length: the new length
* @time_attrs: file times to be updated (e.g. ATTR_MTIME|ATTR_CTIME)
- * @filp: an open file or NULL (see file_truncate() as well)
+ * @filp: an open file or NULL
*/
-int do_truncate(struct dentry *dentry, loff_t length, unsigned int time_attrs,
- struct file *filp)
+static inline int do_truncate(struct dentry *dentry, loff_t length,
+ unsigned int time_attrs, struct file *filp)
{
int err;
struct iattr newattrs;
@@ -229,14 +229,16 @@ int do_truncate(struct dentry *dentry, l
}
/*
- * file_truncate - truncate (or extend) an open file
- * @filp: the open file
+ * path_truncate - truncate (or extend) a file
+ * @path: the path structure to truncate
* @length: the new length
* @time_attrs: file times to be updated (e.g. ATTR_MTIME|ATTR_CTIME)
+ * @filp: an open file or NULL
*/
-int file_truncate(struct file *filp, loff_t length, unsigned int time_attrs)
+int path_truncate(struct path *path, loff_t length, unsigned int time_attrs,
+ struct file *filp)
{
- return do_truncate(filp->f_path.dentry, length, time_attrs, filp);
+ return do_truncate(path->dentry, length, time_attrs, filp);
}
static long do_sys_truncate(const char __user * path, loff_t length)
@@ -290,7 +292,7 @@ static long do_sys_truncate(const char _
error = locks_verify_truncate(inode, NULL, length);
if (!error) {
DQUOT_INIT(inode);
- error = do_truncate(nd.path.dentry, length, 0, NULL);
+ error = path_truncate(&nd.path, length, 0, NULL);
}
put_write_and_out:
@@ -343,7 +345,8 @@ static long do_sys_ftruncate(unsigned in
error = locks_verify_truncate(inode, file, length);
if (!error)
- error = file_truncate(file, length, ATTR_MTIME|ATTR_CTIME);
+ error = path_truncate(&file->f_path, length,
+ ATTR_MTIME|ATTR_CTIME, file);
out_putf:
fput(file);
out:
--- vfs.orig/include/linux/fs.h
+++ vfs/include/linux/fs.h
@@ -1609,10 +1609,8 @@ static inline int break_lease(struct ino
/* fs/open.c */
-extern int do_truncate(struct dentry *, loff_t start, unsigned int time_attrs,
- struct file *filp);
-extern int file_truncate(struct file *filp, loff_t start,
- unsigned int time_attrs);
+extern int path_truncate(struct path *path, loff_t start,
+ unsigned int time_attrs, struct file *filp);
extern long do_sys_open(int dfd, const char __user *filename, int flags,
int mode);
extern struct file *filp_open(const char *, int, int);
--- vfs.orig/mm/tiny-shmem.c
+++ vfs/mm/tiny-shmem.c
@@ -80,7 +80,7 @@ struct file *shmem_file_setup(char *name
inode->i_nlink = 0; /* It is unlinked */
/* notify everyone as to the change of file size */
- error = file_truncate(file, size, 0);
+ error = path_truncate(&file->f_path, size, 0, file);
if (error < 0)
goto close_file;
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists