From: Jan Kara <[email protected]>
Forbid user from changing file flags on quota files. User has no bussiness
in playing with these flags when quota is on. Furthermore there is a
remote possibility of deadlock due to a lock inversion between quota file's
i_mutex and transaction's start (i_mutex for quota file is locked only when
trasaction is started in quota operations) in ext3 and ext4.
Signed-off-by: Jan Kara <[email protected]>
Cc: LIOU Payphone <[email protected]>
Cc: <[email protected]>
Acked-by: Dave Kleikamp <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
---
fs/ext2/ioctl.c | 5 +++++
fs/ext3/ioctl.c | 5 +++++
fs/ext4/ioctl.c | 5 +++++
fs/jfs/ioctl.c | 3 +++
fs/reiserfs/ioctl.c | 3 +++
5 files changed, 21 insertions(+)
diff -puN fs/ext2/ioctl.c~forbid-user-to-change-file-flags-on-quota-files fs/ext2/ioctl.c
--- a/fs/ext2/ioctl.c~forbid-user-to-change-file-flags-on-quota-files
+++ a/fs/ext2/ioctl.c
@@ -47,6 +47,11 @@ int ext2_ioctl (struct inode * inode, st
flags &= ~EXT2_DIRSYNC_FL;
mutex_lock(&inode->i_mutex);
+ /* Is it quota file? Do not allow user to mess with it */
+ if (IS_NOQUOTA(inode)) {
+ mutex_unlock(&inode->i_mutex);
+ return -EPERM;
+ }
oldflags = ei->i_flags;
/*
diff -puN fs/ext3/ioctl.c~forbid-user-to-change-file-flags-on-quota-files fs/ext3/ioctl.c
--- a/fs/ext3/ioctl.c~forbid-user-to-change-file-flags-on-quota-files
+++ a/fs/ext3/ioctl.c
@@ -51,6 +51,11 @@ int ext3_ioctl (struct inode * inode, st
flags &= ~EXT3_DIRSYNC_FL;
mutex_lock(&inode->i_mutex);
+ /* Is it quota file? Do not allow user to mess with it */
+ if (IS_NOQUOTA(inode)) {
+ mutex_unlock(&inode->i_mutex);
+ return -EPERM;
+ }
oldflags = ei->i_flags;
/* The JOURNAL_DATA flag is modifiable only by root */
diff -puN fs/ext4/ioctl.c~forbid-user-to-change-file-flags-on-quota-files fs/ext4/ioctl.c
--- a/fs/ext4/ioctl.c~forbid-user-to-change-file-flags-on-quota-files
+++ a/fs/ext4/ioctl.c
@@ -51,6 +51,11 @@ int ext4_ioctl (struct inode * inode, st
flags &= ~EXT4_DIRSYNC_FL;
mutex_lock(&inode->i_mutex);
+ /* Is it quota file? Do not allow user to mess with it */
+ if (IS_NOQUOTA(inode)) {
+ mutex_unlock(&inode->i_mutex);
+ return -EPERM;
+ }
oldflags = ei->i_flags;
/* The JOURNAL_DATA flag is modifiable only by root */
diff -puN fs/jfs/ioctl.c~forbid-user-to-change-file-flags-on-quota-files fs/jfs/ioctl.c
--- a/fs/jfs/ioctl.c~forbid-user-to-change-file-flags-on-quota-files
+++ a/fs/jfs/ioctl.c
@@ -79,6 +79,9 @@ int jfs_ioctl(struct inode * inode, stru
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;
jfs_get_inode_flags(jfs_inode);
oldflags = jfs_inode->mode2;
diff -puN fs/reiserfs/ioctl.c~forbid-user-to-change-file-flags-on-quota-files fs/reiserfs/ioctl.c
--- a/fs/reiserfs/ioctl.c~forbid-user-to-change-file-flags-on-quota-files
+++ a/fs/reiserfs/ioctl.c
@@ -57,6 +57,9 @@ int reiserfs_ioctl(struct inode *inode,
if (get_user(flags, (int __user *)arg))
return -EFAULT;
+ /* Is it quota file? Do not allow user to mess with it. */
+ if (IS_NOQUOTA(inode))
+ return -EPERM;
if (((flags ^ REISERFS_I(inode)->
i_attrs) & (REISERFS_IMMUTABLE_FL |
REISERFS_APPEND_FL))
_