I took another look at this and reorganized things a bit. I re-worked the
f_owner/send_sigio hooks:
- Moved file_ops->alloc_security up to get_empty_filp()
- Added file_ops->free_security to put_filp()
- Removed fown_ops entirely (functionality moved to file_ops)
- Created a file_ops->set_fowner call
- Added calls to set_fowner in tty_io.c, dnotify.c, locks.c,
fcntl.c
Attached is a diff that should be relative to the previous one (I couldn't
access the bk repository). An exception is that a hook for ioctl was also
added.
chris.
On Tue, 12 Jun 2001, Chris Wright wrote:
> * Chris Vance (cvanceat_private) wrote:
> >
> > I have added hooks in the following locations:
>
> thanks again for the patch. i finally had the time last night to review
> the hooks. some comments below...
>
> > fcntl/fcntl64 (sys_fcntl/sys_fcntl64): Added hooks to authorize these
> > operations. Additionally, a security field was added to the
> > fown_struct so that the attributes of the owning process could
> > be maintained for later use in send_sigio_to_task.
> >
> > fcntl (send_sigio_to_task): Added hook to verify signal permissions.
>
> i'm not real familiar with this code path, so please correct my
> misunderstandings.
>
> the fown_ops->alloc_security in F_SETOWN is a perfect example of needing
> to separate allocation from setting the security blob. i think this
> should really be set (not alloc), as the space should have already been
> allocated, (perhaps in get_empty_filp). and i don't see any free (granted
> this may be a simple 32 bit security id superimposed on the void *, but
> we should get the chance to free in case it is actual allocated space).
> should the blob be set when a lease is established, or directory notification
> turned on? since both of these actions maninpulate the f_owner.pid, and
> these can generate io signals to be sent. i want to make sure that the
> send_sigiotask() check will always have a properly filled in f_owner.security
> blob.
>
> -chris
>
> _______________________________________________
> linux-security-module mailing list
> linux-security-moduleat_private
> http://mail.wirex.com/mailman/listinfo/linux-security-module
>
Index: drivers/char/tty_io.c
===================================================================
RCS file: /cvs/lsm/lsm/drivers/char/tty_io.c,v
retrieving revision 1.1
retrieving revision 1.2
diff -u -r1.1 -r1.2
--- drivers/char/tty_io.c 2001/05/09 20:10:10 1.1
+++ drivers/char/tty_io.c 2001/06/13 14:13:31 1.2
@@ -1462,6 +1462,10 @@
if (!waitqueue_active(&tty->read_wait))
tty->minimum_to_wake = 1;
if (filp->f_owner.pid == 0) {
+ retval = security_ops->file_ops->set_fowner(filp);
+ if (retval)
+ return retval;
+
filp->f_owner.pid = (-tty->pgrp) ? : current->pid;
filp->f_owner.uid = current->uid;
filp->f_owner.euid = current->euid;
Index: fs/dnotify.c
===================================================================
RCS file: /cvs/lsm/lsm/fs/dnotify.c,v
retrieving revision 1.1
retrieving revision 1.2
diff -u -r1.1 -r1.2
--- fs/dnotify.c 2001/05/09 20:09:21 1.1
+++ fs/dnotify.c 2001/06/13 14:13:31 1.2
@@ -45,6 +45,7 @@
struct dnotify_struct **prev;
struct inode *inode;
int turning_off = (arg & ~DN_MULTISHOT) == 0;
+ int error;
if (!turning_off && !dir_notify_enable)
return -EINVAL;
@@ -75,6 +76,13 @@
}
if (turning_off)
goto out;
+
+ error = security_ops->file_ops->set_fowner(filp);
+ if (error) {
+ write_unlock(&dn_lock);
+ return error;
+ }
+
filp->f_owner.pid = current->pid;
filp->f_owner.uid = current->uid;
filp->f_owner.euid = current->euid;
Index: fs/fcntl.c
===================================================================
RCS file: /cvs/lsm/lsm/fs/fcntl.c,v
retrieving revision 1.2
retrieving revision 1.3
diff -u -r1.2 -r1.3
--- fs/fcntl.c 2001/06/04 17:19:28 1.2
+++ fs/fcntl.c 2001/06/13 14:13:31 1.3
@@ -273,15 +273,20 @@
break;
case F_SETOWN:
lock_kernel();
+
+ err = security_ops->file_ops->set_fowner(filp);
+ if (err) {
+ unlock_kernel();
+ break;
+ }
+
filp->f_owner.pid = arg;
filp->f_owner.uid = current->uid;
filp->f_owner.euid = current->euid;
- err = 0;
+
if (S_ISSOCK (filp->f_dentry->d_inode->i_mode))
err = sock_fcntl (filp, F_SETOWN, arg);
- if (!err)
- err = security_ops->fown_ops->alloc_security(&filp->f_owner);
unlock_kernel();
break;
case F_GETSIG:
@@ -396,7 +401,7 @@
(fown->uid ^ p->suid) && (fown->uid ^ p->uid))
return;
- if (security_ops->fown_ops->send_sigiotask(p, fown, fd, reason))
+ if (security_ops->file_ops->send_sigiotask(p, fown, fd, reason))
return;
switch (fown->signum) {
Index: fs/file_table.c
===================================================================
RCS file: /cvs/lsm/lsm/fs/file_table.c,v
retrieving revision 1.2
retrieving revision 1.3
diff -u -r1.2 -r1.3
--- fs/file_table.c 2001/05/09 20:19:19 1.2
+++ fs/file_table.c 2001/06/13 14:13:31 1.3
@@ -41,6 +41,12 @@
list_del(&f->f_list);
files_stat.nr_free_files--;
new_one:
+ if (security_ops->file_ops->alloc_security(f)) {
+ list_add(&f->f_list, &free_list);
+ files_stat.nr_free_files++;
+ file_list_unlock();
+ return NULL;
+ }
memset(f, 0, sizeof(*f));
atomic_set(&f->f_count,1);
f->f_version = ++event;
@@ -143,6 +149,7 @@
void put_filp(struct file *file)
{
if(atomic_dec_and_test(&file->f_count)) {
+ security_ops->file_ops->free_security(file);
file_list_lock();
list_del(&file->f_list);
list_add(&file->f_list, &free_list);
Index: fs/ioctl.c
===================================================================
RCS file: /cvs/lsm/lsm/fs/ioctl.c,v
retrieving revision 1.1
retrieving revision 1.2
diff -u -r1.1 -r1.2
--- fs/ioctl.c 2001/05/09 20:09:21 1.1
+++ fs/ioctl.c 2001/06/13 13:49:09 1.2
@@ -7,6 +7,7 @@
#include <linux/mm.h>
#include <linux/smp_lock.h>
#include <linux/file.h>
+#include <linux/security.h>
#include <asm/uaccess.h>
#include <asm/ioctls.h>
@@ -56,6 +57,14 @@
if (!filp)
goto out;
error = 0;
+
+ /* Call the Linux Security Module to perform its checks. */
+ error = security_ops->file_ops->ioctl(filp, cmd, arg);
+ if (error) {
+ fput(filp);
+ goto out;
+ }
+
lock_kernel();
switch (cmd) {
case FIOCLEX:
Index: fs/locks.c
===================================================================
RCS file: /cvs/lsm/lsm/fs/locks.c,v
retrieving revision 1.1
retrieving revision 1.2
diff -u -r1.1 -r1.2
--- fs/locks.c 2001/05/09 20:09:21 1.1
+++ fs/locks.c 2001/06/13 14:13:31 1.2
@@ -1269,6 +1269,11 @@
fl->fl_next = *before;
*before = fl;
list_add(&fl->fl_link, &file_lock_list);
+
+ error = security_ops->file_ops->set_fowner(filp);
+ if (error)
+ goto out_unlock;
+
filp->f_owner.pid = current->pid;
filp->f_owner.uid = current->uid;
filp->f_owner.euid = current->euid;
Index: fs/open.c
===================================================================
RCS file: /cvs/lsm/lsm/fs/open.c,v
retrieving revision 1.4
retrieving revision 1.5
diff -u -r1.4 -r1.5
--- fs/open.c 2001/05/18 19:23:21 1.4
+++ fs/open.c 2001/06/13 14:13:31 1.5
@@ -667,10 +667,6 @@
}
f->f_flags &= ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC);
- error = -EACCES;
- if (security_ops->file_ops->alloc_security (f))
- goto cleanup_all;
-
return f;
cleanup_all:
Index: include/linux/security.h
===================================================================
RCS file: /cvs/lsm/lsm/include/linux/security.h,v
retrieving revision 1.10
retrieving revision 1.12
diff -u -r1.10 -r1.12
--- include/linux/security.h 2001/06/12 15:35:07 1.10
+++ include/linux/security.h 2001/06/13 14:13:31 1.12
@@ -81,7 +81,7 @@
int (* llseek) (struct file *);
int (* read) (struct file *);
int (* write) (struct file *);
- int (* ioctl) (struct file *); // need more than file*
+ int (* ioctl) (struct file *, unsigned int cmd, unsigned long arg);
int (* mmap) (struct file *, unsigned long, unsigned long);
int (* mprotect) (struct vm_area_struct *, unsigned long);
int (* lock) (struct file *);
@@ -89,11 +89,7 @@
int (* writev) (struct file *);
int (* fcntl) (struct file *, unsigned int, unsigned long);
int (* fcntl64) (struct file *, unsigned int, unsigned long);
-};
-
-struct fown_security_ops {
- int (* alloc_security) (struct fown_struct *);
- void (* free_security) (struct fown_struct *);
+ int (* set_fowner) (struct file *);
int (* send_sigiotask) (struct task_struct *, struct fown_struct *, int, int);
};
@@ -180,7 +176,6 @@
struct super_block_security_ops * sb_ops;
struct inode_security_ops * inode_ops;
struct file_security_ops * file_ops;
- struct fown_security_ops * fown_ops;
struct task_security_ops * task_ops;
struct socket_security_ops * socket_ops;
struct module_security_ops * module_ops;
Index: kernel/capability_plug.c
===================================================================
RCS file: /cvs/lsm/lsm/kernel/capability_plug.c,v
retrieving revision 1.9
retrieving revision 1.11
diff -u -r1.9 -r1.11
--- kernel/capability_plug.c 2001/06/12 15:35:07 1.9
+++ kernel/capability_plug.c 2001/06/13 14:13:31 1.11
@@ -372,7 +372,7 @@
{
return 0;
}
-static int cap_file_ioctl(struct file *file)
+static int cap_file_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
return 0;
}
@@ -409,18 +409,12 @@
return 0;
}
-/* fown security operations */
-static int cap_fown_alloc_security(struct fown_struct *fown)
+static int cap_file_set_fowner(struct file *file)
{
- return 0;
-}
-
-static void cap_fown_free_security(struct fown_struct *fown)
-{
return;
}
-static int cap_fown_send_sigiotask(struct task_struct *tsk,
+static int cap_file_send_sigiotask(struct task_struct *tsk,
struct fown_struct *fown, int fd,
int reason)
{
@@ -641,12 +635,8 @@
writev: cap_file_writev,
fcntl: cap_file_fcntl,
fcntl64: cap_file_fcntl64,
-};
-
-static struct fown_security_ops cap_fown_ops = {
- alloc_security: cap_fown_alloc_security,
- free_security: cap_fown_free_security,
- send_sigiotask: cap_fown_send_sigiotask,
+ set_fowner: cap_file_set_fowner,
+ send_sigiotask: cap_file_send_sigiotask,
};
static struct task_security_ops cap_task_ops = {
@@ -725,7 +715,6 @@
sb_ops: &cap_sb_ops,
inode_ops: &cap_inode_ops,
file_ops: &cap_file_ops,
- fown_ops: &cap_fown_ops,
task_ops: &cap_task_ops,
socket_ops: &cap_socket_ops,
module_ops: &cap_module_ops,
Index: kernel/security.c
===================================================================
RCS file: /cvs/lsm/lsm/kernel/security.c,v
retrieving revision 1.9
retrieving revision 1.12
diff -u -r1.9 -r1.12
--- kernel/security.c 2001/06/12 15:35:07 1.9
+++ kernel/security.c 2001/06/13 14:13:31 1.12
@@ -87,7 +87,7 @@
static int dummy_file_llseek (struct file *file) {return 0;}
static int dummy_file_read (struct file *file) {return 0;}
static int dummy_file_write (struct file *file) {return 0;}
-static int dummy_file_ioctl (struct file *file) {return 0;}
+static int dummy_file_ioctl (struct file *file, unsigned int command, unsigned long arg) {return 0;}
static int dummy_file_mmap (struct file *file, unsigned long prot, unsigned long flags) {return 0;}
static int dummy_file_mprotect (struct vm_area_struct *vma, unsigned long prot) {return 0;}
static int dummy_file_lock (struct file *file) {return 0;}
@@ -95,11 +95,9 @@
static int dummy_file_writev (struct file *file) {return 0;}
static int dummy_file_fcntl (struct file *file, unsigned int cmd, unsigned long arg) {return 0;}
static int dummy_file_fcntl64 (struct file *file, unsigned int cmd, unsigned long arg) {return 0;}
+static int dummy_file_set_fowner (struct file *file) {return 0;}
+static int dummy_file_send_sigiotask (struct task_struct *tsk, struct fown_struct *fown, int fd, int reason) {return 0;}
-static int dummy_fown_alloc_security (struct fown_struct *fown) {return 0;}
-static void dummy_fown_free_security (struct fown_struct *fown) {return;}
-static int dummy_fown_send_sigiotask (struct task_struct *tsk, struct fown_struct *fown, int fd, int reason) {return 0;}
-
static int dummy_task_create (void) {return 0;}
static int dummy_task_alloc_security (struct task_struct *p) {return 0;}
static void dummy_task_free_security (struct task_struct *p) {return;}
@@ -194,12 +192,8 @@
writev: dummy_file_writev,
fcntl: dummy_file_fcntl,
fcntl64: dummy_file_fcntl64,
-};
-
-static struct fown_security_ops dummy_fown_ops = {
- alloc_security: dummy_fown_alloc_security,
- free_security: dummy_fown_free_security,
- send_sigiotask: dummy_fown_send_sigiotask,
+ set_fowner: dummy_file_set_fowner,
+ send_sigiotask: dummy_file_send_sigiotask,
};
static struct task_security_ops dummy_task_ops = {
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This archive was generated by hypermail 2b30 : Wed Jun 13 2001 - 10:03:01 PDT