Commit e47776a0 authored by Jan Kara's avatar Jan Kara Committed by Linus Torvalds
Browse files

Forbid user to change file flags on quota files 



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: default avatarJan Kara <jack@suse.cz>
Cc: LIOU Payphone <lioupayphone@gmail.com>
Cc: <linux-ext4@vger.kernel.org>
Acked-by: default avatarDave Kleikamp <shaggy@austin.ibm.com>
Cc: <reiserfs-dev@namesys.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 28822f22

fs/ext2/ioctl.c

+5 −0
Original line number Diff line number Diff line
@@ -47,6 +47,11 @@ int ext2_ioctl (struct inode * inode, struct file * filp, unsigned int cmd, 
			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;



		/*

fs/ext3/ioctl.c

+5 −0
Original line number Diff line number Diff line
@@ -51,6 +51,11 @@ int ext3_ioctl (struct inode * inode, struct file * filp, unsigned int cmd, 
			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 */

fs/ext4/ioctl.c

+5 −0
Original line number Diff line number Diff line
@@ -51,6 +51,11 @@ int ext4_ioctl (struct inode * inode, struct file * filp, unsigned int cmd, 
			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 */

fs/jfs/ioctl.c

+3 −0
Original line number Diff line number Diff line
@@ -79,6 +79,9 @@ int jfs_ioctl(struct inode * inode, struct file * filp, unsigned int cmd, 
		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;

fs/reiserfs/ioctl.c

+3 −0
Original line number Diff line number Diff line
@@ -57,6 +57,9 @@ int reiserfs_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, 
			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))

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