A-Team_Digital_Solutions/android_kernel_motorola_sm6375
Watch
2
0
Fork
You've already forked android_kernel_motorola_sm6375
 0
mirror of https://github.com/BobTheBlinker/android_kernel_motorola_sm6375.git synced 2026-10-29 11:11:45 -04:00
Code Issues Projects Releases Packages Wiki Activity

[PATCH] r/o bind mounts: elevate write count for ioctls()

Browse source 
Some ioctl()s can cause writes to the filesystem.  Take these, and make them
use mnt_want/drop_write() instead.

[AV: updated]

Acked-by: Al Viro <[email protected]>
Signed-off-by: Christoph Hellwig <[email protected]>
Signed-off-by: Dave Hansen <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Al Viro <[email protected]>
This commit is contained in:
Dave Hansen 2008-02-15 14:37:46 -08:00 • committed by Al Viro
commit 42a74f206b
9 changed files with 265 additions and 155 deletions
Download patch file Download diff file Expand all files Collapse all files

33
fs/jfs/ioctl.c
View file

@ -8,6 +8,7 @@
#include <linux/fs.h>
#include <linux/ctype.h>
#include <linux/capability.h>
#include <linux/mount.h>
#include <linux/time.h>
#include <linux/sched.h>
#include <asm/current.h>
@ -65,23 +66,30 @@ long jfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
return put_user(flags, (int __user *) arg);
case JFS_IOC_SETFLAGS: {
unsigned int oldflags;
int err;
if (IS_RDONLY(inode))
return -EROFS;
err = mnt_want_write(filp->f_path.mnt);
if (err)
return err;
if (!is_owner_or_cap(inode))
return -EACCES;
if (get_user(flags, (int __user *) arg))
return -EFAULT;
if (!is_owner_or_cap(inode)) {
err = -EACCES;
goto setflags_out;
}
if (get_user(flags, (int __user *) arg)) {
err = -EFAULT;
goto setflags_out;
}
flags = jfs_map_ext2(flags, 1);
if (!S_ISDIR(inode->i_mode))
flags &= ~JFS_DIRSYNC_FL;
/* Is it quota file? Do not allow user to mess with it */
if (IS_NOQUOTA(inode))
return -EPERM;
if (IS_NOQUOTA(inode)) {
err = -EPERM;
goto setflags_out;
}
/* Lock against other parallel changes of flags */
mutex_lock(&inode->i_mutex);
@ -98,7 +106,8 @@ long jfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
(JFS_APPEND_FL | JFS_IMMUTABLE_FL))) {
if (!capable(CAP_LINUX_IMMUTABLE)) {
mutex_unlock(&inode->i_mutex);
return -EPERM;
err = -EPERM;
goto setflags_out;
}
}
@ -110,7 +119,9 @@ long jfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
mutex_unlock(&inode->i_mutex);
inode->i_ctime = CURRENT_TIME_SEC;
mark_inode_dirty(inode);
return 0;
setflags_out:
mnt_drop_write(filp->f_path.mnt);
return err;
}
default:
return -ENOTTY;