Seems to look good from IMA side.
On Wed, Jul 26, 2017 at 4:22 PM, Mimi Zohar <zohar@xxxxxxxxxxxxxxxxxx> wrote:
> From: Christoph Hellwig <hch@xxxxxx>
>
> Add a new ->integrity_read file operation to read data for integrity
> hash collection. This is defined to be equivalent to ->read_iter,
> except that it will be called with the i_rwsem held exclusively.
>
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
> Cc: Matthew Garrett <matthew.garrett@xxxxxxxxxx>
> Cc: Jan Kara <jack@xxxxxxxx>
> Cc: "Theodore Ts'o" <tytso@xxxxxxx>
> Cc: Andreas Dilger <adilger.kernel@xxxxxxxxx>
> Cc: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
> Cc: Chao Yu <yuchao0@xxxxxxxxxx>
> Cc: Steven Whitehouse <swhiteho@xxxxxxxxxx>
> Cc: Bob Peterson <rpeterso@xxxxxxxxxx>
> Cc: David Woodhouse <dwmw2@xxxxxxxxxxxxx>
> Cc: Dave Kleikamp <shaggy@xxxxxxxxxx>
> Cc: Ryusuke Konishi <konishi.ryusuke@xxxxxxxxxxxxx>
> Cc: Mark Fasheh <mfasheh@xxxxxxxxxxx>
> Cc: Joel Becker <jlbec@xxxxxxxxxxxx>
> Cc: Richard Weinberger <richard@xxxxxx>
> Cc: "Darrick J. Wong" <darrick.wong@xxxxxxxxxx>
> Cc: Hugh Dickins <hughd@xxxxxxxxxx>
> Cc: Chris Mason <clm@xxxxxx>
> Signed-off-by: Mimi Zohar <zohar@xxxxxxxxxxxxxxxxxx>
>
> Changelog v4:
> - define ext2/4 specific ->integrity_read functions.
> - properly fail file open with O_DIRECT on filesystem not mounted
> with "-o dax".
>
> ---
> Changelog v3:
> - define simple_read_iter_from_buffer
> - replace the existing efivarfs ->read method with ->read_iter method.
> - squashed other fs definitions of ->integrity_read with this patch.
>
> Changelog v2:
> - change iovec to kvec
>
> Changelog v1:
> - update the patch description, removing the concept that the presence of
> ->integrity_read indicates that the file system can support IMA. (Mimi)
>
> fs/btrfs/file.c | 1 +
> fs/efivarfs/file.c | 12 +++++++-----
> fs/ext2/file.c | 17 +++++++++++++++++
> fs/ext4/file.c | 23 +++++++++++++++++++++++
> fs/f2fs/file.c | 1 +
> fs/gfs2/file.c | 2 ++
> fs/jffs2/file.c | 1 +
> fs/jfs/file.c | 1 +
> fs/libfs.c | 32 ++++++++++++++++++++++++++++++++
> fs/nilfs2/file.c | 1 +
> fs/ocfs2/file.c | 1 +
> fs/ramfs/file-mmu.c | 1 +
> fs/ramfs/file-nommu.c | 1 +
> fs/ubifs/file.c | 1 +
> fs/xfs/xfs_file.c | 21 +++++++++++++++++++++
> include/linux/fs.h | 3 +++
> mm/shmem.c | 1 +
> security/integrity/iint.c | 20 ++++++++++++++------
> 18 files changed, 129 insertions(+), 11 deletions(-)
>
> diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
> index 9e75d8a39aac..2542dc66c85c 100644
> --- a/fs/btrfs/file.c
> +++ b/fs/btrfs/file.c
> @@ -3125,6 +3125,7 @@ const struct file_operations btrfs_file_operations = {
> #endif
> .clone_file_range = btrfs_clone_file_range,
> .dedupe_file_range = btrfs_dedupe_file_range,
> + .integrity_read = generic_file_read_iter,
> };
>
> void btrfs_auto_defrag_exit(void)
> diff --git a/fs/efivarfs/file.c b/fs/efivarfs/file.c
> index 5f22e74bbade..17955a92a5b3 100644
> --- a/fs/efivarfs/file.c
> +++ b/fs/efivarfs/file.c
> @@ -64,9 +64,10 @@ static ssize_t efivarfs_file_write(struct file *file,
> return bytes;
> }
>
> -static ssize_t efivarfs_file_read(struct file *file, char __user *userbuf,
> - size_t count, loff_t *ppos)
> +static ssize_t efivarfs_file_read_iter(struct kiocb *iocb,
> + struct iov_iter *iter)
> {
> + struct file *file = iocb->ki_filp;
> struct efivar_entry *var = file->private_data;
> unsigned long datasize = 0;
> u32 attributes;
> @@ -96,8 +97,8 @@ static ssize_t efivarfs_file_read(struct file *file, char __user *userbuf,
> goto out_free;
>
> memcpy(data, &attributes, sizeof(attributes));
> - size = simple_read_from_buffer(userbuf, count, ppos,
> - data, datasize + sizeof(attributes));
> + size = simple_read_iter_from_buffer(iocb, iter, data,
> + datasize + sizeof(attributes));
> out_free:
> kfree(data);
>
> @@ -174,8 +175,9 @@ efivarfs_file_ioctl(struct file *file, unsigned int cmd, unsigned long p)
>
> const struct file_operations efivarfs_file_operations = {
> .open = simple_open,
> - .read = efivarfs_file_read,
> + .read_iter = efivarfs_file_read_iter,
> .write = efivarfs_file_write,
> .llseek = no_llseek,
> .unlocked_ioctl = efivarfs_file_ioctl,
> + .integrity_read = efivarfs_file_read_iter,
> };
> diff --git a/fs/ext2/file.c b/fs/ext2/file.c
> index d34d32bdc944..111069de1973 100644
> --- a/fs/ext2/file.c
> +++ b/fs/ext2/file.c
> @@ -192,6 +192,22 @@ static ssize_t ext2_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
> return generic_file_read_iter(iocb, to);
> }
>
> +static ssize_t ext2_file_integrity_read_iter(struct kiocb *iocb,
> + struct iov_iter *to)
> +{
> + struct inode *inode = file_inode(iocb->ki_filp);
> +
> + lockdep_assert_held(&inode->i_rwsem);
> +#ifdef CONFIG_FS_DAX
> + if (!iov_iter_count(to))
> + return 0; /* skip atime */
> +
> + if (IS_DAX(iocb->ki_filp->f_mapping->host))
> + return dax_iomap_rw(iocb, to, &ext2_iomap_ops);
> +#endif
> + return generic_file_read_iter(iocb, to);
> +}
> +
> static ssize_t ext2_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
> {
> #ifdef CONFIG_FS_DAX
> @@ -216,6 +232,7 @@ const struct file_operations ext2_file_operations = {
> .get_unmapped_area = thp_get_unmapped_area,
> .splice_read = generic_file_splice_read,
> .splice_write = iter_file_splice_write,
> + .integrity_read = ext2_file_integrity_read_iter,
> };
>
> const struct inode_operations ext2_file_inode_operations = {
> diff --git a/fs/ext4/file.c b/fs/ext4/file.c
> index 58294c9a7e1d..cb423fff935f 100644
> --- a/fs/ext4/file.c
> +++ b/fs/ext4/file.c
> @@ -74,6 +74,28 @@ static ssize_t ext4_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
> return generic_file_read_iter(iocb, to);
> }
>
> +static ssize_t ext4_file_integrity_read_iter(struct kiocb *iocb,
> + struct iov_iter *to)
> +{
> + struct inode *inode = file_inode(iocb->ki_filp);
> + int o_direct = iocb->ki_flags & IOCB_DIRECT;
> +
> + lockdep_assert_held(&inode->i_rwsem);
> + if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
> + return -EIO;
> +
> + if (!iov_iter_count(to))
> + return 0; /* skip atime */
> +
> +#ifdef CONFIG_FS_DAX
> + if (IS_DAX(inode))
> + return dax_iomap_rw(iocb, to, &ext4_iomap_ops);
> +#endif
> + if (o_direct)
> + return -EINVAL;
> + return generic_file_read_iter(iocb, to);
> +}
> +
> /*
> * Called when an inode is released. Note that this is different
> * from ext4_file_open: open gets called at every open, but release
> @@ -747,6 +769,7 @@ const struct file_operations ext4_file_operations = {
> .splice_read = generic_file_splice_read,
> .splice_write = iter_file_splice_write,
> .fallocate = ext4_fallocate,
> + .integrity_read = ext4_file_integrity_read_iter,
> };
>
> const struct inode_operations ext4_file_inode_operations = {
> diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
> index 2706130c261b..82ea81da0b2d 100644
> --- a/fs/f2fs/file.c
> +++ b/fs/f2fs/file.c
> @@ -2514,4 +2514,5 @@ const struct file_operations f2fs_file_operations = {
> #endif
> .splice_read = generic_file_splice_read,
> .splice_write = iter_file_splice_write,
> + .integrity_read = generic_file_read_iter,
> };
> diff --git a/fs/gfs2/file.c b/fs/gfs2/file.c
> index c2062a108d19..9b49d09ba180 100644
> --- a/fs/gfs2/file.c
> +++ b/fs/gfs2/file.c
> @@ -1124,6 +1124,7 @@ const struct file_operations gfs2_file_fops = {
> .splice_write = gfs2_file_splice_write,
> .setlease = simple_nosetlease,
> .fallocate = gfs2_fallocate,
> + .integrity_read = generic_file_read_iter,
> };
>
> const struct file_operations gfs2_dir_fops = {
> @@ -1152,6 +1153,7 @@ const struct file_operations gfs2_file_fops_nolock = {
> .splice_write = gfs2_file_splice_write,
> .setlease = generic_setlease,
> .fallocate = gfs2_fallocate,
> + .integrity_read = generic_file_read_iter,
> };
>
> const struct file_operations gfs2_dir_fops_nolock = {
> diff --git a/fs/jffs2/file.c b/fs/jffs2/file.c
> index c12476e309c6..5a63034cccf5 100644
> --- a/fs/jffs2/file.c
> +++ b/fs/jffs2/file.c
> @@ -57,6 +57,7 @@ const struct file_operations jffs2_file_operations =
> .mmap = generic_file_readonly_mmap,
> .fsync = jffs2_fsync,
> .splice_read = generic_file_splice_read,
> + .integrity_read = generic_file_read_iter,
> };
>
> /* jffs2_file_inode_operations */
> diff --git a/fs/jfs/file.c b/fs/jfs/file.c
> index 739492c7a3fd..423512a810e4 100644
> --- a/fs/jfs/file.c
> +++ b/fs/jfs/file.c
> @@ -162,4 +162,5 @@ const struct file_operations jfs_file_operations = {
> #ifdef CONFIG_COMPAT
> .compat_ioctl = jfs_compat_ioctl,
> #endif
> + .integrity_read = generic_file_read_iter,
> };
> diff --git a/fs/libfs.c b/fs/libfs.c
> index 3aabe553fc45..99333264a0a7 100644
> --- a/fs/libfs.c
> +++ b/fs/libfs.c
> @@ -16,6 +16,7 @@
> #include <linux/exportfs.h>
> #include <linux/writeback.h>
> #include <linux/buffer_head.h> /* sync_mapping_buffers */
> +#include <linux/uio.h>
>
> #include <linux/uaccess.h>
>
> @@ -676,6 +677,37 @@ ssize_t simple_write_to_buffer(void *to, size_t available, loff_t *ppos,
> EXPORT_SYMBOL(simple_write_to_buffer);
>
> /**
> + * simple_read_iter_from_buffer - copy data from the buffer to user space
> + * @iocb: struct containing the file, the current position and other info
> + * @to: the user space buffer to read to
> + * @from: the buffer to read from
> + * @available: the size of the buffer
> + *
> + * The simple_read_iter_from_buffer() function reads up to @available bytes
> + * from the current buffer into the user space buffer.
> + *
> + * On success, the current buffer offset is advanced by the number of bytes
> + * read, or a negative value is returned on error.
> + **/
> +ssize_t simple_read_iter_from_buffer(struct kiocb *iocb, struct iov_iter *to,
> + const void *from, size_t available)
> +{
> + loff_t pos = iocb->ki_pos;
> + size_t ret;
> +
> + if (pos < 0)
> + return -EINVAL;
> + if (pos >= available)
> + return 0;
> + ret = copy_to_iter(from + pos, available - pos, to);
> + if (!ret && iov_iter_count(to))
> + return -EFAULT;
> + iocb->ki_pos = pos + ret;
> + return ret;
> +}
> +EXPORT_SYMBOL(simple_read_iter_from_buffer);
> +
> +/**
> * memory_read_from_buffer - copy data from the buffer
> * @to: the kernel space buffer to read to
> * @count: the maximum number of bytes to read
> diff --git a/fs/nilfs2/file.c b/fs/nilfs2/file.c
> index c5fa3dee72fc..55e058ac487f 100644
> --- a/fs/nilfs2/file.c
> +++ b/fs/nilfs2/file.c
> @@ -150,6 +150,7 @@ const struct file_operations nilfs_file_operations = {
> /* .release = nilfs_release_file, */
> .fsync = nilfs_sync_file,
> .splice_read = generic_file_splice_read,
> + .integrity_read = generic_file_read_iter,
> };
>
> const struct inode_operations nilfs_file_inode_operations = {
> diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
> index bfeb647459d9..2832a7c92acd 100644
> --- a/fs/ocfs2/file.c
> +++ b/fs/ocfs2/file.c
> @@ -2536,6 +2536,7 @@ const struct file_operations ocfs2_fops = {
> .fallocate = ocfs2_fallocate,
> .clone_file_range = ocfs2_file_clone_range,
> .dedupe_file_range = ocfs2_file_dedupe_range,
> + .integrity_read = ocfs2_file_read_iter,
> };
>
> const struct file_operations ocfs2_dops = {
> diff --git a/fs/ramfs/file-mmu.c b/fs/ramfs/file-mmu.c
> index 12af0490322f..4f24d1b589b1 100644
> --- a/fs/ramfs/file-mmu.c
> +++ b/fs/ramfs/file-mmu.c
> @@ -47,6 +47,7 @@ const struct file_operations ramfs_file_operations = {
> .splice_write = iter_file_splice_write,
> .llseek = generic_file_llseek,
> .get_unmapped_area = ramfs_mmu_get_unmapped_area,
> + .integrity_read = generic_file_read_iter,
> };
>
> const struct inode_operations ramfs_file_inode_operations = {
> diff --git a/fs/ramfs/file-nommu.c b/fs/ramfs/file-nommu.c
> index 2ef7ce75c062..5ee704fa84e0 100644
> --- a/fs/ramfs/file-nommu.c
> +++ b/fs/ramfs/file-nommu.c
> @@ -50,6 +50,7 @@ const struct file_operations ramfs_file_operations = {
> .splice_read = generic_file_splice_read,
> .splice_write = iter_file_splice_write,
> .llseek = generic_file_llseek,
> + .integrity_read = generic_file_read_iter,
> };
>
> const struct inode_operations ramfs_file_inode_operations = {
> diff --git a/fs/ubifs/file.c b/fs/ubifs/file.c
> index 8cad0b19b404..5e52a315e18b 100644
> --- a/fs/ubifs/file.c
> +++ b/fs/ubifs/file.c
> @@ -1747,4 +1747,5 @@ const struct file_operations ubifs_file_operations = {
> #ifdef CONFIG_COMPAT
> .compat_ioctl = ubifs_compat_ioctl,
> #endif
> + .integrity_read = generic_file_read_iter,
> };
> diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
> index c4893e226fd8..0a6704b563d6 100644
> --- a/fs/xfs/xfs_file.c
> +++ b/fs/xfs/xfs_file.c
> @@ -292,6 +292,26 @@ xfs_file_read_iter(
> return ret;
> }
>
> +static ssize_t
> +xfs_integrity_read(
> + struct kiocb *iocb,
> + struct iov_iter *to)
> +{
> + struct inode *inode = file_inode(iocb->ki_filp);
> + struct xfs_mount *mp = XFS_I(inode)->i_mount;
> +
> + lockdep_assert_held(&inode->i_rwsem);
> +
> + XFS_STATS_INC(mp, xs_read_calls);
> +
> + if (XFS_FORCED_SHUTDOWN(mp))
> + return -EIO;
> +
> + if (IS_DAX(inode))
> + return dax_iomap_rw(iocb, to, &xfs_iomap_ops);
> + return generic_file_read_iter(iocb, to);
> +}
> +
> /*
> * Zero any on disk space between the current EOF and the new, larger EOF.
> *
> @@ -1175,6 +1195,7 @@ const struct file_operations xfs_file_operations = {
> .fallocate = xfs_file_fallocate,
> .clone_file_range = xfs_file_clone_range,
> .dedupe_file_range = xfs_file_dedupe_range,
> + .integrity_read = xfs_integrity_read,
> };
>
> const struct file_operations xfs_dir_file_operations = {
> diff --git a/include/linux/fs.h b/include/linux/fs.h
> index 6e1fd5d21248..8d0d10e1dd93 100644
> --- a/include/linux/fs.h
> +++ b/include/linux/fs.h
> @@ -1699,6 +1699,7 @@ struct file_operations {
> u64);
> ssize_t (*dedupe_file_range)(struct file *, u64, u64, struct file *,
> u64);
> + ssize_t (*integrity_read)(struct kiocb *, struct iov_iter *);
> } __randomize_layout;
>
> struct inode_operations {
> @@ -3097,6 +3098,8 @@ extern void simple_release_fs(struct vfsmount **mount, int *count);
>
> extern ssize_t simple_read_from_buffer(void __user *to, size_t count,
> loff_t *ppos, const void *from, size_t available);
> +extern ssize_t simple_read_iter_from_buffer(struct kiocb *iocb,
> + struct iov_iter *to, const void *from, size_t available);
> extern ssize_t simple_write_to_buffer(void *to, size_t available, loff_t *ppos,
> const void __user *from, size_t count);
>
> diff --git a/mm/shmem.c b/mm/shmem.c
> index b0aa6075d164..805d99011ca4 100644
> --- a/mm/shmem.c
> +++ b/mm/shmem.c
> @@ -3849,6 +3849,7 @@ static const struct file_operations shmem_file_operations = {
> .splice_read = generic_file_splice_read,
> .splice_write = iter_file_splice_write,
> .fallocate = shmem_fallocate,
> + .integrity_read = shmem_file_read_iter,
> #endif
> };
>
> diff --git a/security/integrity/iint.c b/security/integrity/iint.c
> index 6fc888ca468e..df04f35a1d40 100644
> --- a/security/integrity/iint.c
> +++ b/security/integrity/iint.c
> @@ -21,6 +21,7 @@
> #include <linux/rbtree.h>
> #include <linux/file.h>
> #include <linux/uaccess.h>
> +#include <linux/uio.h>
> #include "integrity.h"
>
> static struct rb_root integrity_iint_tree = RB_ROOT;
> @@ -184,18 +185,25 @@ security_initcall(integrity_iintcache_init);
> int integrity_kernel_read(struct file *file, loff_t offset,
> void *addr, unsigned long count)
> {
> - mm_segment_t old_fs;
> - char __user *buf = (char __user *)addr;
> + struct inode *inode = file_inode(file);
> + struct kvec iov = { .iov_base = addr, .iov_len = count };
> + struct kiocb kiocb;
> + struct iov_iter iter;
> ssize_t ret;
>
> + lockdep_assert_held(&inode->i_rwsem);
> +
> if (!(file->f_mode & FMODE_READ))
> return -EBADF;
> + if (!file->f_op->integrity_read)
> + return -EBADF;
>
> - old_fs = get_fs();
> - set_fs(get_ds());
> - ret = __vfs_read(file, buf, count, &offset);
> - set_fs(old_fs);
> + init_sync_kiocb(&kiocb, file);
> + kiocb.ki_pos = offset;
> + iov_iter_kvec(&iter, READ | ITER_KVEC, &iov, 1, count);
>
> + ret = file->f_op->integrity_read(&kiocb, &iter);
> + BUG_ON(ret == -EIOCBQUEUED);
> return ret;
> }
>
> --
> 2.7.4
>
> --
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--
Thanks,
Dmitry
