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Violators will be prosecuted for from ; Wed, 2 Aug 2017 01:38:39 +1000 Subject: Re: [PATCH v4 2/5] ima: use fs method to read integrity data From: Mimi Zohar To: Jan Kara Cc: Christoph Hellwig , Al Viro , James Morris , linux-fsdevel@vger.kernel.org, linux-ima-devel@lists.sourceforge.net, linux-security-module@vger.kernel.org, Matthew Garrett , Jan Kara , "Theodore Ts'o" , Andreas Dilger , Jaegeuk Kim , Chao Yu , Steven Whitehouse , Bob Peterson , David Woodhouse , Dave Kleikamp , Ryusuke Konishi , Mark Fasheh , Joel Becker , Richard Weinberger , "Darrick J. Wong" , Hugh Dickins , Chris Mason Date: Tue, 01 Aug 2017 11:38:24 -0400 In-Reply-To: <20170801104253.GF4215@quack2.suse.cz> References: <1501075375-29469-1-git-send-email-zohar@linux.vnet.ibm.com> <1501075375-29469-3-git-send-email-zohar@linux.vnet.ibm.com> <20170731070151.GA18621@quack2.suse.cz> <1501528133.9230.123.camel@linux.vnet.ibm.com> <20170801104253.GF4215@quack2.suse.cz> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Message-Id: <1501601904.9230.147.camel@linux.vnet.ibm.com> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On Tue, 2017-08-01 at 12:42 +0200, Jan Kara wrote: > On Mon 31-07-17 15:08:53, Mimi Zohar wrote: > > On Mon, 2017-07-31 at 09:01 +0200, Jan Kara wrote: > > > On Wed 26-07-17 09:22:52, Mimi Zohar wrote: > > > > From: Christoph Hellwig > > > > > > > > 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. > > > > > > The patch looks mostly good to me. > > > > Thanks!  Can I include your Ack-by? > > After gfs2 & ocfs2 matters are settled... > > > > > > Just one question: How did you select > > > filesystems that implement .integrity_read method? > > > > Initially I started out looking at the fs/.../Kconfig, but after > > spending a while looking at the number of filesystems, I gave up and > > asked Christoph (offline) where to begin.  I also compared the > > measurement list from before and after the change and noticed some > > missing file measurements (eg. ramfs, shmem, efivarfs). > > OK, makes sense. > > > > And I still maintain > > > that it would be IMHO safer to not pretend we support IMA on gfs2 and ocfs2 > > > unless you either make sure they are mounted in local-only mode or figure > > > out how to deal with proper cluster locking. > > > > Agreed.  With patch 1/7 "ima: always measure and audit files in > > policy", at least a file measurement containing a 0x00's hash value > > will be included in the IMA measurement list. > > Well, but for OCFS2 and GFS2 you have defined .integrity_read methods to > generic_file_read_iter() and they will return data so IMA will think > everything is fine. Just they may crash while doing so or return bogus data > due to insufficient locking generic_file_read_iter() provides. So my > suggestion is to just not provide .integrity_read for these two filesystems > until you (or someone else) can figure out how to do that safely. Sorry my explanation above wasn't clear.  Yes, I'll remove the integrity_read method definitions for gfs2 and ocfs2.  As a result of removing the integrity_read operation, the measurement list will contain 0x00 hash values, instead of the real file hash. Mimi  > > > > > Signed-off-by: Christoph Hellwig > > > > Cc: Matthew Garrett > > > > Cc: Jan Kara > > > > Cc: "Theodore Ts'o" > > > > Cc: Andreas Dilger > > > > Cc: Jaegeuk Kim > > > > Cc: Chao Yu > > > > Cc: Steven Whitehouse > > > > Cc: Bob Peterson > > > > Cc: David Woodhouse > > > > Cc: Dave Kleikamp > > > > Cc: Ryusuke Konishi > > > > Cc: Mark Fasheh > > > > Cc: Joel Becker > > > > Cc: Richard Weinberger > > > > Cc: "Darrick J. Wong" > > > > Cc: Hugh Dickins > > > > Cc: Chris Mason > > > > Signed-off-by: Mimi Zohar > > > > > > > > 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 > > > > #include > > > > #include /* sync_mapping_buffers */ > > > > +#include > > > > > > > > #include > > > > > > > > @@ -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 > > > > #include > > > > #include > > > > +#include > > > > #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 > > > > > > > > > > From mboxrd@z Thu Jan 1 00:00:00 1970 From: zohar@linux.vnet.ibm.com (Mimi Zohar) Date: Tue, 01 Aug 2017 11:38:24 -0400 Subject: [PATCH v4 2/5] ima: use fs method to read integrity data In-Reply-To: <20170801104253.GF4215@quack2.suse.cz> References: <1501075375-29469-1-git-send-email-zohar@linux.vnet.ibm.com> <1501075375-29469-3-git-send-email-zohar@linux.vnet.ibm.com> <20170731070151.GA18621@quack2.suse.cz> <1501528133.9230.123.camel@linux.vnet.ibm.com> <20170801104253.GF4215@quack2.suse.cz> Message-ID: <1501601904.9230.147.camel@linux.vnet.ibm.com> To: linux-security-module@vger.kernel.org List-Id: linux-security-module.vger.kernel.org On Tue, 2017-08-01 at 12:42 +0200, Jan Kara wrote: > On Mon 31-07-17 15:08:53, Mimi Zohar wrote: > > On Mon, 2017-07-31 at 09:01 +0200, Jan Kara wrote: > > > On Wed 26-07-17 09:22:52, Mimi Zohar wrote: > > > > From: Christoph Hellwig > > > > > > > > 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. > > > > > > The patch looks mostly good to me. > > > > Thanks! ?Can I include your Ack-by? > > After gfs2 & ocfs2 matters are settled... > > > > > > Just one question: How did you select > > > filesystems that implement .integrity_read method? > > > > Initially I started out looking at the fs/.../Kconfig, but after > > spending a while looking at the number of filesystems, I gave up and > > asked Christoph (offline) where to begin.??I also compared the > > measurement list from before and after the change and noticed some > > missing file measurements (eg. ramfs, shmem, efivarfs). > > OK, makes sense. > > > > And I still maintain > > > that it would be IMHO safer to not pretend we support IMA on gfs2 and ocfs2 > > > unless you either make sure they are mounted in local-only mode or figure > > > out how to deal with proper cluster locking. > > > > Agreed. ?With patch 1/7 "ima: always measure and audit files in > > policy", at least a file measurement containing a 0x00's hash value > > will be included in the IMA measurement list. > > Well, but for OCFS2 and GFS2 you have defined .integrity_read methods to > generic_file_read_iter() and they will return data so IMA will think > everything is fine. Just they may crash while doing so or return bogus data > due to insufficient locking generic_file_read_iter() provides. So my > suggestion is to just not provide .integrity_read for these two filesystems > until you (or someone else) can figure out how to do that safely. Sorry my explanation above wasn't clear. ?Yes, I'll remove the integrity_read method definitions for gfs2 and ocfs2. ?As a result of removing the integrity_read operation, the measurement list will contain 0x00 hash values, instead of the real file hash. Mimi? > > > > > Signed-off-by: Christoph Hellwig > > > > Cc: Matthew Garrett > > > > Cc: Jan Kara > > > > Cc: "Theodore Ts'o" > > > > Cc: Andreas Dilger > > > > Cc: Jaegeuk Kim > > > > Cc: Chao Yu > > > > Cc: Steven Whitehouse > > > > Cc: Bob Peterson > > > > Cc: David Woodhouse > > > > Cc: Dave Kleikamp > > > > Cc: Ryusuke Konishi > > > > Cc: Mark Fasheh > > > > Cc: Joel Becker > > > > Cc: Richard Weinberger > > > > Cc: "Darrick J. Wong" > > > > Cc: Hugh Dickins > > > > Cc: Chris Mason > > > > Signed-off-by: Mimi Zohar > > > > > > > > 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 > > > > #include > > > > #include /* sync_mapping_buffers */ > > > > +#include > > > > > > > > #include > > > > > > > > @@ -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 > > > > #include > > > > #include > > > > +#include > > > > #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 > > > > > > > > > > -- To unsubscribe from this list: send the line "unsubscribe linux-security-module" in the body of a message to majordomo at vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html