Commit 7b0e492e authored by Darrick J. Wong's avatar Darrick J. Wong
Browse files

vfs: create a generic checking function for FS_IOC_FSSETXATTR 



Create a generic checking function for the incoming FS_IOC_FSSETXATTR
fsxattr values so that we can standardize some of the implementation
behaviors.

Signed-off-by: default avatarDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: default avatarJan Kara <jack@suse.cz>
parent 5aca2842

fs/btrfs/ioctl.c

+6 −11
Original line number Diff line number Diff line
@@ -375,9 +375,7 @@ static int btrfs_ioctl_fsgetxattr(struct file *file, void __user *arg) 
	struct btrfs_inode *binode = BTRFS_I(file_inode(file));

	struct fsxattr fa;



	memset(&fa, 0, sizeof(fa));

	fa.fsx_xflags = btrfs_inode_flags_to_xflags(binode->flags);



	simple_fill_fsxattr(&fa, btrfs_inode_flags_to_xflags(binode->flags));

	if (copy_to_user(arg, &fa, sizeof(fa)))

		return -EFAULT;
@@ -390,7 +388,7 @@ static int btrfs_ioctl_fssetxattr(struct file *file, void __user *arg) 
	struct btrfs_inode *binode = BTRFS_I(inode);

	struct btrfs_root *root = binode->root;

	struct btrfs_trans_handle *trans;

	struct fsxattr fa;

	struct fsxattr fa, old_fa;

	unsigned old_flags;

	unsigned old_i_flags;

	int ret = 0;
@@ -401,7 +399,6 @@ static int btrfs_ioctl_fssetxattr(struct file *file, void __user *arg) 
	if (btrfs_root_readonly(root))

		return -EROFS;



	memset(&fa, 0, sizeof(fa));

	if (copy_from_user(&fa, arg, sizeof(fa)))

		return -EFAULT;
@@ -421,13 +418,11 @@ static int btrfs_ioctl_fssetxattr(struct file *file, void __user *arg) 
	old_flags = binode->flags;

	old_i_flags = inode->i_flags;



	/* We need the capabilities to change append-only or immutable inode */

	if (((old_flags & (BTRFS_INODE_APPEND | BTRFS_INODE_IMMUTABLE)) ||

	     (fa.fsx_xflags & (FS_XFLAG_APPEND | FS_XFLAG_IMMUTABLE))) &&

	    !capable(CAP_LINUX_IMMUTABLE)) {

		ret = -EPERM;

	simple_fill_fsxattr(&old_fa,

			    btrfs_inode_flags_to_xflags(binode->flags));

	ret = vfs_ioc_fssetxattr_check(inode, &old_fa, &fa);

	if (ret)

		goto out_unlock;

	}



	if (fa.fsx_xflags & FS_XFLAG_SYNC)

		binode->flags |= BTRFS_INODE_SYNC;

fs/ext4/ioctl.c

+17 −8
Original line number Diff line number Diff line
@@ -721,6 +721,17 @@ static int ext4_ioctl_check_project(struct inode *inode, struct fsxattr *fa) 
	return 0;

}



static void ext4_fill_fsxattr(struct inode *inode, struct fsxattr *fa)

{

	struct ext4_inode_info *ei = EXT4_I(inode);



	simple_fill_fsxattr(fa, ext4_iflags_to_xflags(ei->i_flags &

						      EXT4_FL_USER_VISIBLE));



	if (ext4_has_feature_project(inode->i_sb))

		fa->fsx_projid = from_kprojid(&init_user_ns, ei->i_projid);

}



long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)

{

	struct inode *inode = file_inode(filp);
@@ -1089,13 +1100,7 @@ resizefs_out: 
	{

		struct fsxattr fa;



		memset(&fa, 0, sizeof(struct fsxattr));

		fa.fsx_xflags = ext4_iflags_to_xflags(ei->i_flags & EXT4_FL_USER_VISIBLE);



		if (ext4_has_feature_project(inode->i_sb)) {

			fa.fsx_projid = (__u32)from_kprojid(&init_user_ns,

				EXT4_I(inode)->i_projid);

		}

		ext4_fill_fsxattr(inode, &fa);



		if (copy_to_user((struct fsxattr __user *)arg,

				 &fa, sizeof(fa)))
@@ -1104,7 +1109,7 @@ resizefs_out: 
	}

	case EXT4_IOC_FSSETXATTR:

	{

		struct fsxattr fa;

		struct fsxattr fa, old_fa;

		int err;



		if (copy_from_user(&fa, (struct fsxattr __user *)arg,
@@ -1127,7 +1132,11 @@ resizefs_out: 
			return err;



		inode_lock(inode);

		ext4_fill_fsxattr(inode, &old_fa);

		err = ext4_ioctl_check_project(inode, &fa);

		if (err)

			goto out;

		err = vfs_ioc_fssetxattr_check(inode, &old_fa, &fa);

		if (err)

			goto out;

		flags = (ei->i_flags & ~EXT4_FL_XFLAG_VISIBLE) |

fs/inode.c

+23 −0
Original line number Diff line number Diff line
@@ -2194,3 +2194,26 @@ int vfs_ioc_setflags_prepare(struct inode *inode, unsigned int oldflags, 
	return 0;

}

EXPORT_SYMBOL(vfs_ioc_setflags_prepare);



/*

 * Generic function to check FS_IOC_FSSETXATTR values and reject any invalid

 * configurations.

 *

 * Note: the caller should be holding i_mutex, or else be sure that they have

 * exclusive access to the inode structure.

 */

int vfs_ioc_fssetxattr_check(struct inode *inode, const struct fsxattr *old_fa,

			     struct fsxattr *fa)

{

	/*

	 * Can't modify an immutable/append-only file unless we have

	 * appropriate permission.

	 */

	if ((old_fa->fsx_xflags ^ fa->fsx_xflags) &

			(FS_XFLAG_IMMUTABLE | FS_XFLAG_APPEND) &&

	    !capable(CAP_LINUX_IMMUTABLE))

		return -EPERM;



	return 0;

}

EXPORT_SYMBOL(vfs_ioc_fssetxattr_check);

fs/xfs/xfs_ioctl.c

+40 −29
Original line number Diff line number Diff line
@@ -879,37 +879,44 @@ xfs_di2lxflags( 
	return flags;

}



STATIC int

xfs_ioc_fsgetxattr(

	xfs_inode_t		*ip,

	int			attr,

	void			__user *arg)

static void

xfs_fill_fsxattr(

	struct xfs_inode	*ip,

	bool			attr,

	struct fsxattr		*fa)

{

	struct fsxattr		fa;



	memset(&fa, 0, sizeof(struct fsxattr));



	xfs_ilock(ip, XFS_ILOCK_SHARED);

	fa.fsx_xflags = xfs_ip2xflags(ip);

	fa.fsx_extsize = ip->i_d.di_extsize << ip->i_mount->m_sb.sb_blocklog;

	fa.fsx_cowextsize = ip->i_d.di_cowextsize <<

	simple_fill_fsxattr(fa, xfs_ip2xflags(ip));

	fa->fsx_extsize = ip->i_d.di_extsize << ip->i_mount->m_sb.sb_blocklog;

	fa->fsx_cowextsize = ip->i_d.di_cowextsize <<

			ip->i_mount->m_sb.sb_blocklog;

	fa.fsx_projid = xfs_get_projid(ip);

	fa->fsx_projid = xfs_get_projid(ip);



	if (attr) {

		if (ip->i_afp) {

			if (ip->i_afp->if_flags & XFS_IFEXTENTS)

				fa.fsx_nextents = xfs_iext_count(ip->i_afp);

				fa->fsx_nextents = xfs_iext_count(ip->i_afp);

			else

				fa.fsx_nextents = ip->i_d.di_anextents;

				fa->fsx_nextents = ip->i_d.di_anextents;

		} else

			fa.fsx_nextents = 0;

			fa->fsx_nextents = 0;

	} else {

		if (ip->i_df.if_flags & XFS_IFEXTENTS)

			fa.fsx_nextents = xfs_iext_count(&ip->i_df);

			fa->fsx_nextents = xfs_iext_count(&ip->i_df);

		else

			fa.fsx_nextents = ip->i_d.di_nextents;

			fa->fsx_nextents = ip->i_d.di_nextents;

	}

}



STATIC int

xfs_ioc_fsgetxattr(

	xfs_inode_t		*ip,

	int			attr,

	void			__user *arg)

{

	struct fsxattr		fa;



	xfs_ilock(ip, XFS_ILOCK_SHARED);

	xfs_fill_fsxattr(ip, attr, &fa);

	xfs_iunlock(ip, XFS_ILOCK_SHARED);



	if (copy_to_user(arg, &fa, sizeof(fa)))
@@ -1035,15 +1042,6 @@ xfs_ioctl_setattr_xflags( 
	if ((fa->fsx_xflags & FS_XFLAG_DAX) && xfs_is_reflink_inode(ip))

		return -EINVAL;



	/*

	 * Can't modify an immutable/append-only file unless

	 * we have appropriate permission.

	 */

	if (((ip->i_d.di_flags & (XFS_DIFLAG_IMMUTABLE | XFS_DIFLAG_APPEND)) ||

	     (fa->fsx_xflags & (FS_XFLAG_IMMUTABLE | FS_XFLAG_APPEND))) &&

	    !capable(CAP_LINUX_IMMUTABLE))

		return -EPERM;



	/* diflags2 only valid for v3 inodes. */

	di_flags2 = xfs_flags2diflags2(ip, fa->fsx_xflags);

	if (di_flags2 && ip->i_d.di_version < 3)
@@ -1323,6 +1321,7 @@ xfs_ioctl_setattr( 
	xfs_inode_t		*ip,

	struct fsxattr		*fa)

{

	struct fsxattr		old_fa;

	struct xfs_mount	*mp = ip->i_mount;

	struct xfs_trans	*tp;

	struct xfs_dquot	*udqp = NULL;
@@ -1370,7 +1369,6 @@ xfs_ioctl_setattr( 
		goto error_free_dquots;

	}





	if (XFS_IS_QUOTA_RUNNING(mp) && XFS_IS_PQUOTA_ON(mp) &&

	    xfs_get_projid(ip) != fa->fsx_projid) {

		code = xfs_qm_vop_chown_reserve(tp, ip, udqp, NULL, pdqp,
@@ -1379,6 +1377,11 @@ xfs_ioctl_setattr( 
			goto error_trans_cancel;

	}



	xfs_fill_fsxattr(ip, false, &old_fa);

	code = vfs_ioc_fssetxattr_check(VFS_I(ip), &old_fa, fa);

	if (code)

		goto error_trans_cancel;



	code = xfs_ioctl_setattr_check_extsize(ip, fa);

	if (code)

		goto error_trans_cancel;
@@ -1489,6 +1492,7 @@ xfs_ioc_setxflags( 
{

	struct xfs_trans	*tp;

	struct fsxattr		fa;

	struct fsxattr		old_fa;

	unsigned int		flags;

	int			join_flags = 0;

	int			error;
@@ -1524,6 +1528,13 @@ xfs_ioc_setxflags( 
		goto out_drop_write;

	}



	xfs_fill_fsxattr(ip, false, &old_fa);

	error = vfs_ioc_fssetxattr_check(VFS_I(ip), &old_fa, &fa);

	if (error) {

		xfs_trans_cancel(tp);

		goto out_drop_write;

	}



	error = xfs_ioctl_setattr_xflags(tp, ip, &fa);

	if (error) {

		xfs_trans_cancel(tp);

include/linux/fs.h

+9 −0
Original line number Diff line number Diff line
@@ -3549,4 +3549,13 @@ static inline struct sock *io_uring_get_socket(struct file *file) 
int vfs_ioc_setflags_prepare(struct inode *inode, unsigned int oldflags,

			     unsigned int flags);



int vfs_ioc_fssetxattr_check(struct inode *inode, const struct fsxattr *old_fa,

			     struct fsxattr *fa);



static inline void simple_fill_fsxattr(struct fsxattr *fa, __u32 xflags)

{

	memset(fa, 0, sizeof(*fa));

	fa->fsx_xflags = xflags;

}



#endif /* _LINUX_FS_H */

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