| Message ID | 171175868775.1988170.1235485201931301190.stgit@frogsfrogsfrogs (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [01/29] xfs: use unsigned ints for non-negative quantities in xfs_attr_remote.c | expand |
On 2024-03-29 17:39:27, Darrick J. Wong wrote: > From: Andrey Albershteyn <aalbersh@redhat.com> > > Add integration with fs-verity. The XFS store fs-verity metadata in > the extended file attributes. The metadata consist of verity > descriptor and Merkle tree blocks. > > The descriptor is stored under "vdesc" extended attribute. The > Merkle tree blocks are stored under binary indexes which are offsets > into the Merkle tree. > > When fs-verity is enabled on an inode, the XFS_IVERITY_CONSTRUCTION > flag is set meaning that the Merkle tree is being build. The > initialization ends with storing of verity descriptor and setting > inode on-disk flag (XFS_DIFLAG2_VERITY). > > The verification on read is done in read path of iomap. > > Signed-off-by: Andrey Albershteyn <aalbersh@redhat.com> > Reviewed-by: Darrick J. Wong <djwong@kernel.org> > [djwong: replace caching implementation with an xarray, other cleanups] > Signed-off-by: Darrick J. Wong <djwong@kernel.org> > --- > fs/xfs/Makefile | 2 > fs/xfs/libxfs/xfs_attr.c | 41 +++ > fs/xfs/libxfs/xfs_attr.h | 1 > fs/xfs/libxfs/xfs_da_format.h | 14 + > fs/xfs/libxfs/xfs_ondisk.h | 3 > fs/xfs/libxfs/xfs_verity.c | 58 ++++ > fs/xfs/libxfs/xfs_verity.h | 13 + > fs/xfs/xfs_fsverity.c | 559 +++++++++++++++++++++++++++++++++++++++++ > fs/xfs/xfs_fsverity.h | 20 + > fs/xfs/xfs_icache.c | 4 > fs/xfs/xfs_inode.h | 5 > fs/xfs/xfs_super.c | 17 + > fs/xfs/xfs_trace.h | 32 ++ > 13 files changed, 769 insertions(+) > create mode 100644 fs/xfs/libxfs/xfs_verity.c > create mode 100644 fs/xfs/libxfs/xfs_verity.h > create mode 100644 fs/xfs/xfs_fsverity.c > create mode 100644 fs/xfs/xfs_fsverity.h > > > diff --git a/fs/xfs/Makefile b/fs/xfs/Makefile > index 702f2ddc918a1..a4b2f54914a87 100644 > --- a/fs/xfs/Makefile > +++ b/fs/xfs/Makefile > @@ -57,6 +57,7 @@ xfs-y += $(addprefix libxfs/, \ > xfs_trans_resv.o \ > xfs_trans_space.o \ > xfs_types.o \ > + xfs_verity.o \ > ) > # xfs_rtbitmap is shared with libxfs > xfs-$(CONFIG_XFS_RT) += $(addprefix libxfs/, \ > @@ -142,6 +143,7 @@ xfs-$(CONFIG_XFS_POSIX_ACL) += xfs_acl.o > xfs-$(CONFIG_SYSCTL) += xfs_sysctl.o > xfs-$(CONFIG_COMPAT) += xfs_ioctl32.o > xfs-$(CONFIG_EXPORTFS_BLOCK_OPS) += xfs_pnfs.o > +xfs-$(CONFIG_FS_VERITY) += xfs_fsverity.o > > # notify failure > ifeq ($(CONFIG_MEMORY_FAILURE),y) > diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c > index 931ec563a7460..c3f686411e378 100644 > --- a/fs/xfs/libxfs/xfs_attr.c > +++ b/fs/xfs/libxfs/xfs_attr.c > @@ -27,6 +27,7 @@ > #include "xfs_attr_item.h" > #include "xfs_xattr.h" > #include "xfs_parent.h" > +#include "xfs_verity.h" > > struct kmem_cache *xfs_attr_intent_cache; > > @@ -1262,6 +1263,43 @@ xfs_attr_removename( > goto out_unlock; > } > > +/* > + * Retrieve the value stored in the xattr structure under @args->name. > + * > + * The caller must have initialized @args and must not hold any ILOCKs. > + * > + * Returns -ENOATTR if the name did not already exist. > + */ > +int > +xfs_attr_getname( > + struct xfs_da_args *args) > +{ > + unsigned int lock_mode; > + int error; > + > + ASSERT(!args->trans); > + > + error = xfs_trans_alloc_empty(args->dp->i_mount, &args->trans); > + if (error) > + return error; > + > + lock_mode = xfs_ilock_attr_map_shared(args->dp); > + > + /* Make sure the attr fork iext tree is loaded */ > + if (xfs_inode_hasattr(args->dp)) { > + error = xfs_iread_extents(args->trans, args->dp, XFS_ATTR_FORK); > + if (error) > + goto out_unlock; > + } > + > + error = xfs_attr_get_ilocked(args); > +out_unlock: > + xfs_iunlock(args->dp, lock_mode); > + xfs_trans_cancel(args->trans); > + args->trans = NULL; > + return error; > +} > + > /*======================================================================== > * External routines when attribute list is inside the inode > *========================================================================*/ > @@ -1743,6 +1781,9 @@ xfs_attr_namecheck( > if (!xfs_attr_check_namespace(attr_flags)) > return false; > > + if (attr_flags & XFS_ATTR_VERITY) > + return xfs_verity_namecheck(attr_flags, name, length); > + > /* > * MAXNAMELEN includes the trailing null, but (name/length) leave it > * out, so use >= for the length check. > diff --git a/fs/xfs/libxfs/xfs_attr.h b/fs/xfs/libxfs/xfs_attr.h > index 958bb9e41ddb3..3e43d715bcdd2 100644 > --- a/fs/xfs/libxfs/xfs_attr.h > +++ b/fs/xfs/libxfs/xfs_attr.h > @@ -561,6 +561,7 @@ void xfs_init_attr_trans(struct xfs_da_args *args, struct xfs_trans_res *tres, > > int xfs_attr_setname(struct xfs_da_args *args, bool rsvd); > int xfs_attr_removename(struct xfs_da_args *args, bool rsvd); > +int xfs_attr_getname(struct xfs_da_args *args); > > /* > * Check to see if the attr should be upgraded from non-existent or shortform to > diff --git a/fs/xfs/libxfs/xfs_da_format.h b/fs/xfs/libxfs/xfs_da_format.h > index 8cbda181c2f48..679cf5b4ad4be 100644 > --- a/fs/xfs/libxfs/xfs_da_format.h > +++ b/fs/xfs/libxfs/xfs_da_format.h > @@ -922,4 +922,18 @@ struct xfs_parent_rec { > __be32 p_gen; > } __packed; > > +/* > + * fs-verity attribute name format > + * > + * Merkle tree blocks are stored under extended attributes of the inode. The > + * name of the attributes are byte offsets into merkle tree. > + */ > +struct xfs_merkle_key { > + __be64 mk_offset; > +}; > + > +/* ondisk xattr name used for the fsverity descriptor */ > +#define XFS_VERITY_DESCRIPTOR_NAME "vdesc" > +#define XFS_VERITY_DESCRIPTOR_NAME_LEN (sizeof(XFS_VERITY_DESCRIPTOR_NAME) - 1) > + > #endif /* __XFS_DA_FORMAT_H__ */ > diff --git a/fs/xfs/libxfs/xfs_ondisk.h b/fs/xfs/libxfs/xfs_ondisk.h > index d46352d60d645..e927bb778ffdc 100644 > --- a/fs/xfs/libxfs/xfs_ondisk.h > +++ b/fs/xfs/libxfs/xfs_ondisk.h > @@ -208,6 +208,9 @@ xfs_check_ondisk_structs(void) > XFS_CHECK_VALUE(XFS_DQ_BIGTIME_EXPIRY_MAX << XFS_DQ_BIGTIME_SHIFT, > 16299260424LL); > > + /* fs-verity xattrs */ > + XFS_CHECK_STRUCT_SIZE(struct xfs_merkle_key, 8); > + XFS_CHECK_VALUE(sizeof(XFS_VERITY_DESCRIPTOR_NAME), 6); > } > > #endif /* __XFS_ONDISK_H */ > diff --git a/fs/xfs/libxfs/xfs_verity.c b/fs/xfs/libxfs/xfs_verity.c > new file mode 100644 > index 0000000000000..bda38b3c19698 > --- /dev/null > +++ b/fs/xfs/libxfs/xfs_verity.c > @@ -0,0 +1,58 @@ > +/* SPDX-License-Identifier: GPL-2.0 */ > +/* > + * Copyright (C) 2023 Red Hat, Inc. > + */ > +#include "xfs.h" > +#include "xfs_shared.h" > +#include "xfs_format.h" > +#include "xfs_da_format.h" > +#include "xfs_da_btree.h" > +#include "xfs_trans_resv.h" > +#include "xfs_mount.h" > +#include "xfs_inode.h" > +#include "xfs_log_format.h" > +#include "xfs_attr.h" > +#include "xfs_verity.h" > + > +/* Set a merkle tree offset in preparation for setting merkle tree attrs. */ > +void > +xfs_merkle_key_to_disk( > + struct xfs_merkle_key *key, > + uint64_t offset) > +{ > + key->mk_offset = cpu_to_be64(offset); > +} > + > +/* Retrieve the merkle tree offset from the attr data. */ > +uint64_t > +xfs_merkle_key_from_disk( > + const void *attr_name, > + int namelen) > +{ > + const struct xfs_merkle_key *key = attr_name; > + > + ASSERT(namelen == sizeof(struct xfs_merkle_key)); > + > + return be64_to_cpu(key->mk_offset); > +} > + > +/* Return true if verity attr name is valid. */ > +bool > +xfs_verity_namecheck( > + unsigned int attr_flags, > + const void *name, > + int namelen) > +{ > + if (!(attr_flags & XFS_ATTR_VERITY)) > + return false; > + > + /* > + * Merkle tree pages are stored under u64 indexes; verity descriptor > + * blocks are held in a named attribute. > + */ > + if (namelen != sizeof(struct xfs_merkle_key) && > + namelen != XFS_VERITY_DESCRIPTOR_NAME_LEN) > + return false; > + > + return true; > +} > diff --git a/fs/xfs/libxfs/xfs_verity.h b/fs/xfs/libxfs/xfs_verity.h > new file mode 100644 > index 0000000000000..c01cc0678bc04 > --- /dev/null > +++ b/fs/xfs/libxfs/xfs_verity.h > @@ -0,0 +1,13 @@ > +/* SPDX-License-Identifier: GPL-2.0 */ > +/* > + * Copyright (C) 2022 Red Hat, Inc. > + */ > +#ifndef __XFS_VERITY_H__ > +#define __XFS_VERITY_H__ > + > +void xfs_merkle_key_to_disk(struct xfs_merkle_key *key, uint64_t offset); > +uint64_t xfs_merkle_key_from_disk(const void *attr_name, int namelen); > +bool xfs_verity_namecheck(unsigned int attr_flags, const void *name, > + int namelen); > + > +#endif /* __XFS_VERITY_H__ */ > diff --git a/fs/xfs/xfs_fsverity.c b/fs/xfs/xfs_fsverity.c > new file mode 100644 > index 0000000000000..a4a52575fb3d5 > --- /dev/null > +++ b/fs/xfs/xfs_fsverity.c > @@ -0,0 +1,559 @@ > +/* SPDX-License-Identifier: GPL-2.0 */ > +/* > + * Copyright (C) 2023 Red Hat, Inc. > + */ > +#include "xfs.h" > +#include "xfs_shared.h" > +#include "xfs_format.h" > +#include "xfs_da_format.h" > +#include "xfs_da_btree.h" > +#include "xfs_trans_resv.h" > +#include "xfs_mount.h" > +#include "xfs_inode.h" > +#include "xfs_log_format.h" > +#include "xfs_attr.h" > +#include "xfs_verity.h" > +#include "xfs_bmap_util.h" > +#include "xfs_log_format.h" > +#include "xfs_trans.h" > +#include "xfs_attr_leaf.h" > +#include "xfs_trace.h" > +#include "xfs_quota.h" > +#include "xfs_fsverity.h" > +#include <linux/fsverity.h> > + > +/* > + * Merkle Tree Block Cache > + * ======================= > + * > + * fsverity requires that the filesystem implement caching of ondisk merkle > + * tree blocks. XFS stores merkle tree blocks in the extended attribute data, > + * which makes it important to keep copies in memory for as long as possible. > + * This is performed by allocating the data blob structure defined below, > + * passing the data portion of the blob to xfs_attr_get, and later adding the > + * data blob to an xarray embedded in the xfs_inode structure. > + * > + * The xarray structure indexes merkle tree blocks by the offset given to us by > + * fsverity, which drastically reduces lookups. First, it eliminating the need > + * to walk the xattr structure to find the remote block containing the merkle > + * tree block. Second, access to each block in the xattr structure requires a > + * lookup in the incore extent btree. > + */ > +struct xfs_merkle_blob { > + /* refcount of this item; the cache holds its own ref */ > + refcount_t refcount; > + > + unsigned long flags; > + > + /* Pointer to the merkle tree block, which is power-of-2 sized */ > + void *data; > +}; > + > +#define XFS_MERKLE_BLOB_VERIFIED_BIT (0) /* fsverity validated this */ > + > +/* > + * Allocate a merkle tree blob object to prepare for reading a merkle tree > + * object from disk. > + */ > +static inline struct xfs_merkle_blob * > +xfs_merkle_blob_alloc( > + unsigned int blocksize) > +{ > + struct xfs_merkle_blob *mk; > + > + mk = kmalloc(sizeof(struct xfs_merkle_blob), GFP_KERNEL); > + if (!mk) > + return NULL; > + > + mk->data = kvzalloc(blocksize, GFP_KERNEL); > + if (!mk->data) { > + kfree(mk); > + return NULL; > + } > + > + /* Caller owns this refcount. */ > + refcount_set(&mk->refcount, 1); > + mk->flags = 0; > + return mk; > +} > + > +/* Free a merkle tree blob. */ > +static inline void > +xfs_merkle_blob_rele( > + struct xfs_merkle_blob *mk) > +{ > + if (refcount_dec_and_test(&mk->refcount)) { > + kvfree(mk->data); > + kfree(mk); > + } > +} > + > +/* Initialize the merkle tree block cache */ > +void > +xfs_fsverity_cache_init( > + struct xfs_inode *ip) > +{ > + xa_init(&ip->i_merkle_blocks); > +} > + > +/* > + * Drop all the merkle tree blocks out of the cache. Caller must ensure that > + * there are no active references to cache items. > + */ > +void > +xfs_fsverity_cache_drop( > + struct xfs_inode *ip) > +{ > + XA_STATE(xas, &ip->i_merkle_blocks, 0); > + struct xfs_merkle_blob *mk; > + unsigned long flags; > + > + xas_lock_irqsave(&xas, flags); > + xas_for_each(&xas, mk, ULONG_MAX) { > + ASSERT(refcount_read(&mk->refcount) == 1); > + > + trace_xfs_fsverity_cache_drop(ip, xas.xa_index, _RET_IP_); > + > + xas_store(&xas, NULL); > + xfs_merkle_blob_rele(mk); > + } > + xas_unlock_irqrestore(&xas, flags); > +} > + > +/* Destroy the merkle tree block cache */ > +void > +xfs_fsverity_cache_destroy( > + struct xfs_inode *ip) > +{ > + ASSERT(xa_empty(&ip->i_merkle_blocks)); > + > + /* > + * xa_destroy calls xas_lock from rcu freeing softirq context, so > + * we must use xa*_lock_irqsave. > + */ > + xa_destroy(&ip->i_merkle_blocks); > +} > + > +/* Return a cached merkle tree block, or NULL. */ > +static struct xfs_merkle_blob * > +xfs_fsverity_cache_load( > + struct xfs_inode *ip, > + unsigned long key) > +{ > + XA_STATE(xas, &ip->i_merkle_blocks, key); > + struct xfs_merkle_blob *mk; > + > + /* Look up the cached item and try to get an active ref. */ > + rcu_read_lock(); > + do { > + mk = xas_load(&xas); > + if (xa_is_zero(mk)) > + mk = NULL; > + } while (xas_retry(&xas, mk) || > + (mk && !refcount_inc_not_zero(&mk->refcount))); > + rcu_read_unlock(); > + > + if (!mk) > + return NULL; > + > + trace_xfs_fsverity_cache_load(ip, key, _RET_IP_); > + return mk; > +} > + > +/* > + * Try to store a merkle tree block in the cache with the given key. > + * > + * If the merkle tree block is not already in the cache, the given block @mk > + * will be added to the cache and returned. The caller retains its active > + * reference to @mk. > + * > + * If there was already a merkle block in the cache, it will be returned to > + * the caller with an active reference. @mk will be untouched. > + */ > +static struct xfs_merkle_blob * > +xfs_fsverity_cache_store( > + struct xfs_inode *ip, > + unsigned long key, > + struct xfs_merkle_blob *mk) > +{ > + struct xfs_merkle_blob *old; > + unsigned long flags; > + > + trace_xfs_fsverity_cache_store(ip, key, _RET_IP_); > + > + /* > + * Either replace a NULL entry with mk, or take an active ref to > + * whatever's currently there. > + */ > + xa_lock_irqsave(&ip->i_merkle_blocks, flags); > + do { > + old = __xa_cmpxchg(&ip->i_merkle_blocks, key, NULL, mk, > + GFP_KERNEL); > + } while (old && !refcount_inc_not_zero(&old->refcount)); > + xa_unlock_irqrestore(&ip->i_merkle_blocks, flags); > + > + if (old == NULL) { > + /* > + * There was no previous value. @mk is now live in the cache. > + * Bump the active refcount to transfer ownership to the cache > + * and return @mk to the caller. > + */ > + refcount_inc(&mk->refcount); > + return mk; > + } > + > + /* > + * We obtained an active reference to a previous value in the cache. > + * Return it to the caller. > + */ > + return old; > +} > + > +/* > + * Initialize an args structure to load or store the fsverity descriptor. > + * Caller must ensure @args is zeroed except for value and valuelen. > + */ > +static inline void > +xfs_fsverity_init_vdesc_args( > + struct xfs_inode *ip, > + struct xfs_da_args *args) > +{ > + args->geo = ip->i_mount->m_attr_geo; > + args->whichfork = XFS_ATTR_FORK, > + args->attr_filter = XFS_ATTR_VERITY; > + args->op_flags = XFS_DA_OP_OKNOENT; > + args->dp = ip; > + args->owner = ip->i_ino; > + args->name = XFS_VERITY_DESCRIPTOR_NAME; > + args->namelen = XFS_VERITY_DESCRIPTOR_NAME_LEN; > + xfs_attr_sethash(args); > +} > + > +/* > + * Initialize an args structure to load or store a merkle tree block. > + * Caller must ensure @args is zeroed except for value and valuelen. > + */ > +static inline void > +xfs_fsverity_init_merkle_args( > + struct xfs_inode *ip, > + struct xfs_merkle_key *key, > + uint64_t merkleoff, > + struct xfs_da_args *args) > +{ > + xfs_merkle_key_to_disk(key, merkleoff); > + args->geo = ip->i_mount->m_attr_geo; > + args->whichfork = XFS_ATTR_FORK, > + args->attr_filter = XFS_ATTR_VERITY; > + args->op_flags = XFS_DA_OP_OKNOENT; > + args->dp = ip; > + args->owner = ip->i_ino; > + args->name = (const uint8_t *)key; > + args->namelen = sizeof(struct xfs_merkle_key); > + xfs_attr_sethash(args); > +} > + > +/* Delete the verity descriptor. */ > +static int > +xfs_fsverity_delete_descriptor( > + struct xfs_inode *ip) > +{ > + struct xfs_da_args args = { }; > + > + xfs_fsverity_init_vdesc_args(ip, &args); > + return xfs_attr_removename(&args, false); > +} > + > +/* Delete a merkle tree block. */ > +static int > +xfs_fsverity_delete_merkle_block( > + struct xfs_inode *ip, > + u64 offset) > +{ > + struct xfs_merkle_key name; > + struct xfs_da_args args = { }; > + > + xfs_fsverity_init_merkle_args(ip, &name, offset, &args); > + return xfs_attr_removename(&args, false); > +} > + > +/* Retrieve the verity descriptor. */ > +static int > +xfs_fsverity_get_descriptor( > + struct inode *inode, > + void *buf, > + size_t buf_size) > +{ > + struct xfs_inode *ip = XFS_I(inode); > + struct xfs_da_args args = { > + .value = buf, > + .valuelen = buf_size, > + }; > + int error = 0; > + > + /* > + * The fact that (returned attribute size) == (provided buf_size) is > + * checked by xfs_attr_copy_value() (returns -ERANGE). No descriptor > + * is treated as a short read so that common fsverity code will > + * complain. > + */ > + xfs_fsverity_init_vdesc_args(ip, &args); > + error = xfs_attr_getname(&args); > + if (error == -ENOATTR) > + return 0; > + if (error) > + return error; > + > + return args.valuelen; > +} > + > +/* > + * Clear out old fsverity metadata before we start building a new one. This > + * could happen if, say, we crashed while building fsverity data. > + */ > +static int > +xfs_fsverity_delete_stale_metadata( > + struct xfs_inode *ip, > + u64 new_tree_size, > + unsigned int tree_blocksize) > +{ > + u64 offset; > + int error = 0; > + > + /* > + * Delete as many merkle tree blocks in increasing blkno order until we > + * don't find any more. That ought to be good enough for avoiding > + * dead bloat without excessive runtime. > + */ > + for (offset = new_tree_size; !error; offset += tree_blocksize) { > + if (fatal_signal_pending(current)) > + return -EINTR; > + error = xfs_fsverity_delete_merkle_block(ip, offset); > + if (error) > + break; > + } > + > + return error != -ENOATTR ? error : 0; > +} > + > +/* Prepare to enable fsverity by clearing old metadata. */ > +static int > +xfs_fsverity_begin_enable( > + struct file *filp, > + u64 merkle_tree_size, > + unsigned int tree_blocksize) > +{ > + struct inode *inode = file_inode(filp); > + struct xfs_inode *ip = XFS_I(inode); > + int error; > + > + xfs_assert_ilocked(ip, XFS_IOLOCK_EXCL); > + > + if (IS_DAX(inode)) > + return -EINVAL; > + > + if (xfs_iflags_test_and_set(ip, XFS_VERITY_CONSTRUCTION)) > + return -EBUSY; > + > + error = xfs_qm_dqattach(ip); > + if (error) > + return error; > + > + return xfs_fsverity_delete_stale_metadata(ip, merkle_tree_size, > + tree_blocksize); > +} > + > +/* Try to remove all the fsverity metadata after a failed enablement. */ > +static int > +xfs_fsverity_delete_metadata( > + struct xfs_inode *ip, > + u64 merkle_tree_size, > + unsigned int tree_blocksize) > +{ > + u64 offset; > + int error; > + > + if (!merkle_tree_size) > + return 0; > + > + for (offset = 0; offset < merkle_tree_size; offset += tree_blocksize) { > + if (fatal_signal_pending(current)) > + return -EINTR; > + error = xfs_fsverity_delete_merkle_block(ip, offset); > + if (error == -ENOATTR) > + error = 0; > + if (error) > + return error; > + } > + > + error = xfs_fsverity_delete_descriptor(ip); > + return error != -ENOATTR ? error : 0; > +} > + > +/* Complete (or fail) the process of enabling fsverity. */ > +static int > +xfs_fsverity_end_enable( > + struct file *filp, > + const void *desc, > + size_t desc_size, > + u64 merkle_tree_size, > + unsigned int tree_blocksize) > +{ > + struct xfs_da_args args = { > + .value = (void *)desc, > + .valuelen = desc_size, > + }; > + struct inode *inode = file_inode(filp); > + struct xfs_inode *ip = XFS_I(inode); > + struct xfs_mount *mp = ip->i_mount; > + struct xfs_trans *tp; > + int error = 0; > + > + xfs_assert_ilocked(ip, XFS_IOLOCK_EXCL); > + > + /* fs-verity failed, just cleanup */ > + if (desc == NULL) > + goto out; > + > + xfs_fsverity_init_vdesc_args(ip, &args); > + error = xfs_attr_setname(&args, false); > + if (error) > + goto out; > + > + /* Set fsverity inode flag */ > + error = xfs_trans_alloc_inode(ip, &M_RES(mp)->tr_ichange, > + 0, 0, false, &tp); > + if (error) > + goto out; > + > + /* > + * Ensure that we've persisted the verity information before we enable > + * it on the inode and tell the caller we have sealed the inode. > + */ > + ip->i_diflags2 |= XFS_DIFLAG2_VERITY; > + > + xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); > + xfs_trans_set_sync(tp); > + > + error = xfs_trans_commit(tp); > + xfs_iunlock(ip, XFS_ILOCK_EXCL); > + > + if (!error) > + inode->i_flags |= S_VERITY; > + > +out: > + if (error) { > + int error2; > + > + error2 = xfs_fsverity_delete_metadata(ip, > + merkle_tree_size, tree_blocksize); > + if (error2) > + xfs_alert(ip->i_mount, > + "ino 0x%llx failed to clean up new fsverity metadata, err %d", > + ip->i_ino, error2); > + } > + > + xfs_iflags_clear(ip, XFS_VERITY_CONSTRUCTION); > + return error; > +} > + > +/* Retrieve a merkle tree block. */ > +static int > +xfs_fsverity_read_merkle( > + const struct fsverity_readmerkle *req, > + struct fsverity_blockbuf *block) > +{ > + struct xfs_inode *ip = XFS_I(req->inode); > + struct xfs_merkle_key name; > + struct xfs_da_args args = { > + .valuelen = block->size, > + }; > + struct xfs_merkle_blob *mk, *new_mk; > + unsigned long key = block->offset >> req->log_blocksize; > + int error; > + > + ASSERT(block->offset >> req->log_blocksize <= ULONG_MAX); > + > + /* Is the block already cached? */ > + mk = xfs_fsverity_cache_load(ip, key); > + if (mk) > + goto out_hit; > + > + new_mk = xfs_merkle_blob_alloc(block->size); > + if (!new_mk) > + return -ENOMEM; > + args.value = new_mk->data; > + > + /* Read the block in from disk and try to store it in the cache. */ > + xfs_fsverity_init_merkle_args(ip, &name, block->offset, &args); > + error = xfs_attr_getname(&args); > + if (error) > + goto out_new_mk; > + > + if (!args.valuelen) { > + error = -ENODATA; > + goto out_new_mk; > + } > + > + mk = xfs_fsverity_cache_store(ip, key, new_mk); > + if (mk != new_mk) { > + /* > + * We raced with another thread to populate the cache and lost. > + * Free the new cache blob and continue with the existing one. > + */ > + xfs_merkle_blob_rele(new_mk); > + } > + > +out_hit: > + block->kaddr = (void *)mk->data; > + block->context = mk; > + block->verified = test_bit(XFS_MERKLE_BLOB_VERIFIED_BIT, &mk->flags); > + > + return 0; > + > +out_new_mk: > + xfs_merkle_blob_rele(new_mk); > + return error; > +} > + > +/* Write a merkle tree block. */ > +static int > +xfs_fsverity_write_merkle( > + const struct fsverity_writemerkle *req, > + const void *buf, > + u64 pos, > + unsigned int size) > +{ > + struct inode *inode = req->inode; > + struct xfs_inode *ip = XFS_I(inode); > + struct xfs_merkle_key name; > + struct xfs_da_args args = { > + .value = (void *)buf, > + .valuelen = size, > + }; > + > + xfs_fsverity_init_merkle_args(ip, &name, pos, &args); > + return xfs_attr_setname(&args, false); > +} > + > +/* Drop a cached merkle tree block.. */ > +static void > +xfs_fsverity_drop_merkle( > + struct fsverity_blockbuf *block) > +{ > + struct xfs_merkle_blob *mk = block->context; > + > + if (block->verified) > + set_bit(XFS_MERKLE_BLOB_VERIFIED_BIT, &mk->flags); > + xfs_merkle_blob_rele(mk); > + block->kaddr = NULL; > + block->context = NULL; > +} > + > +const struct fsverity_operations xfs_fsverity_ops = { > + .begin_enable_verity = xfs_fsverity_begin_enable, > + .end_enable_verity = xfs_fsverity_end_enable, > + .get_verity_descriptor = xfs_fsverity_get_descriptor, > + .read_merkle_tree_block = xfs_fsverity_read_merkle, > + .write_merkle_tree_block = xfs_fsverity_write_merkle, > + .drop_merkle_tree_block = xfs_fsverity_drop_merkle, > +}; > diff --git a/fs/xfs/xfs_fsverity.h b/fs/xfs/xfs_fsverity.h > new file mode 100644 > index 0000000000000..277a9f856f518 > --- /dev/null > +++ b/fs/xfs/xfs_fsverity.h > @@ -0,0 +1,20 @@ > +/* SPDX-License-Identifier: GPL-2.0 */ > +/* > + * Copyright (C) 2022 Red Hat, Inc. > + */ > +#ifndef __XFS_FSVERITY_H__ > +#define __XFS_FSVERITY_H__ > + > +#ifdef CONFIG_FS_VERITY > +void xfs_fsverity_cache_init(struct xfs_inode *ip); > +void xfs_fsverity_cache_drop(struct xfs_inode *ip); > +void xfs_fsverity_cache_destroy(struct xfs_inode *ip); > + > +extern const struct fsverity_operations xfs_fsverity_ops; > +#else > +# define xfs_fsverity_cache_init(ip) ((void)0) > +# define xfs_fsverity_cache_drop(ip) ((void)0) > +# define xfs_fsverity_cache_destroy(ip) ((void)0) > +#endif /* CONFIG_FS_VERITY */ > + > +#endif /* __XFS_FSVERITY_H__ */ > diff --git a/fs/xfs/xfs_icache.c b/fs/xfs/xfs_icache.c > index 01bbdbec6663f..0757062c318d0 100644 > --- a/fs/xfs/xfs_icache.c > +++ b/fs/xfs/xfs_icache.c > @@ -28,6 +28,7 @@ > #include "xfs_da_format.h" > #include "xfs_dir2.h" > #include "xfs_imeta.h" > +#include "xfs_fsverity.h" > > #include <linux/iversion.h> > > @@ -118,6 +119,7 @@ xfs_inode_alloc( > spin_lock_init(&ip->i_ioend_lock); > ip->i_next_unlinked = NULLAGINO; > ip->i_prev_unlinked = 0; > + xfs_fsverity_cache_init(ip); > > return ip; > } > @@ -129,6 +131,8 @@ xfs_inode_free_callback( > struct inode *inode = container_of(head, struct inode, i_rcu); > struct xfs_inode *ip = XFS_I(inode); > > + xfs_fsverity_cache_destroy(ip); > + > switch (VFS_I(ip)->i_mode & S_IFMT) { > case S_IFREG: > case S_IFDIR: > diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h > index 5a202706fc4a4..70c5700132b3e 100644 > --- a/fs/xfs/xfs_inode.h > +++ b/fs/xfs/xfs_inode.h > @@ -96,6 +96,9 @@ typedef struct xfs_inode { > spinlock_t i_ioend_lock; > struct work_struct i_ioend_work; > struct list_head i_ioend_list; > +#ifdef CONFIG_FS_VERITY > + struct xarray i_merkle_blocks; > +#endif So, is this fine like this or do you plan to change it to per-ag mapping? I suppose Christoph against adding it to inodes [1] [1]: https://lore.kernel.org/linux-xfs/ZfecSzBoVDW5328l@infradead.org/ > } xfs_inode_t; > > static inline bool xfs_inode_on_unlinked_list(const struct xfs_inode *ip) > @@ -391,6 +394,8 @@ static inline bool xfs_inode_needs_cow_around(struct xfs_inode *ip) > */ > #define XFS_IREMAPPING (1U << 15) > > +#define XFS_VERITY_CONSTRUCTION (1U << 16) /* merkle tree construction */ > + > /* All inode state flags related to inode reclaim. */ > #define XFS_ALL_IRECLAIM_FLAGS (XFS_IRECLAIMABLE | \ > XFS_IRECLAIM | \ > diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c > index 42a1e1f23d3b3..4e398884c46ae 100644 > --- a/fs/xfs/xfs_super.c > +++ b/fs/xfs/xfs_super.c > @@ -30,6 +30,7 @@ > #include "xfs_filestream.h" > #include "xfs_quota.h" > #include "xfs_sysfs.h" > +#include "xfs_fsverity.h" > #include "xfs_ondisk.h" > #include "xfs_rmap_item.h" > #include "xfs_refcount_item.h" > @@ -53,6 +54,7 @@ > #include <linux/fs_context.h> > #include <linux/fs_parser.h> > #include <linux/fsverity.h> > +#include <linux/iomap.h> > > static const struct super_operations xfs_super_operations; > > @@ -672,6 +674,8 @@ xfs_fs_destroy_inode( > ASSERT(!rwsem_is_locked(&inode->i_rwsem)); > XFS_STATS_INC(ip->i_mount, vn_rele); > XFS_STATS_INC(ip->i_mount, vn_remove); > + if (fsverity_active(inode)) > + xfs_fsverity_cache_drop(ip); > fsverity_cleanup_inode(inode); > xfs_inode_mark_reclaimable(ip); > } > @@ -1534,6 +1538,9 @@ xfs_fs_fill_super( > sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ; > #endif > sb->s_op = &xfs_super_operations; > +#ifdef CONFIG_FS_VERITY > + sb->s_vop = &xfs_fsverity_ops; > +#endif > > /* > * Delay mount work if the debug hook is set. This is debug > @@ -1775,10 +1782,20 @@ xfs_fs_fill_super( > xfs_warn(mp, > "EXPERIMENTAL parent pointer feature enabled. Use at your own risk!"); > > + if (xfs_has_verity(mp)) > + xfs_alert(mp, > + "EXPERIMENTAL fsverity feature in use. Use at your own risk!"); > + > error = xfs_mountfs(mp); > if (error) > goto out_filestream_unmount; > > +#ifdef CONFIG_FS_VERITY > + error = iomap_init_fsverity(mp->m_super); > + if (error) > + goto out_unmount; > +#endif > + > root = igrab(VFS_I(mp->m_rootip)); > if (!root) { > error = -ENOENT; > diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h > index e2992b0115ad2..86a8702c1e27c 100644 > --- a/fs/xfs/xfs_trace.h > +++ b/fs/xfs/xfs_trace.h > @@ -5908,6 +5908,38 @@ TRACE_EVENT(xfs_growfs_check_rtgeom, > ); > #endif /* CONFIG_XFS_RT */ > > +#ifdef CONFIG_FS_VERITY > +DECLARE_EVENT_CLASS(xfs_fsverity_cache_class, > + TP_PROTO(struct xfs_inode *ip, unsigned long key, unsigned long caller_ip), > + TP_ARGS(ip, key, caller_ip), > + TP_STRUCT__entry( > + __field(dev_t, dev) > + __field(xfs_ino_t, ino) > + __field(unsigned long, key) > + __field(void *, caller_ip) > + ), > + TP_fast_assign( > + __entry->dev = ip->i_mount->m_super->s_dev; > + __entry->ino = ip->i_ino; > + __entry->key = key; > + __entry->caller_ip = (void *)caller_ip; > + ), > + TP_printk("dev %d:%d ino 0x%llx key 0x%lx caller %pS", > + MAJOR(__entry->dev), MINOR(__entry->dev), > + __entry->ino, > + __entry->key, > + __entry->caller_ip) > +) > + > +#define DEFINE_XFS_FSVERITY_CACHE_EVENT(name) \ > +DEFINE_EVENT(xfs_fsverity_cache_class, name, \ > + TP_PROTO(struct xfs_inode *ip, unsigned long key, unsigned long caller_ip), \ > + TP_ARGS(ip, key, caller_ip)) > +DEFINE_XFS_FSVERITY_CACHE_EVENT(xfs_fsverity_cache_load); > +DEFINE_XFS_FSVERITY_CACHE_EVENT(xfs_fsverity_cache_store); > +DEFINE_XFS_FSVERITY_CACHE_EVENT(xfs_fsverity_cache_drop); > +#endif /* CONFIG_XFS_VERITY */ > + > #endif /* _TRACE_XFS_H */ > > #undef TRACE_INCLUDE_PATH >
On Tue, Apr 02, 2024 at 10:42:44AM +0200, Andrey Albershteyn wrote: > On 2024-03-29 17:39:27, Darrick J. Wong wrote: > > From: Andrey Albershteyn <aalbersh@redhat.com> > > > > Add integration with fs-verity. The XFS store fs-verity metadata in > > the extended file attributes. The metadata consist of verity > > descriptor and Merkle tree blocks. > > > > The descriptor is stored under "vdesc" extended attribute. The > > Merkle tree blocks are stored under binary indexes which are offsets > > into the Merkle tree. > > > > When fs-verity is enabled on an inode, the XFS_IVERITY_CONSTRUCTION > > flag is set meaning that the Merkle tree is being build. The > > initialization ends with storing of verity descriptor and setting > > inode on-disk flag (XFS_DIFLAG2_VERITY). > > > > The verification on read is done in read path of iomap. > > > > Signed-off-by: Andrey Albershteyn <aalbersh@redhat.com> > > Reviewed-by: Darrick J. Wong <djwong@kernel.org> > > [djwong: replace caching implementation with an xarray, other cleanups] > > Signed-off-by: Darrick J. Wong <djwong@kernel.org> > > --- > > fs/xfs/Makefile | 2 > > fs/xfs/libxfs/xfs_attr.c | 41 +++ > > fs/xfs/libxfs/xfs_attr.h | 1 > > fs/xfs/libxfs/xfs_da_format.h | 14 + > > fs/xfs/libxfs/xfs_ondisk.h | 3 > > fs/xfs/libxfs/xfs_verity.c | 58 ++++ > > fs/xfs/libxfs/xfs_verity.h | 13 + > > fs/xfs/xfs_fsverity.c | 559 +++++++++++++++++++++++++++++++++++++++++ > > fs/xfs/xfs_fsverity.h | 20 + > > fs/xfs/xfs_icache.c | 4 > > fs/xfs/xfs_inode.h | 5 > > fs/xfs/xfs_super.c | 17 + > > fs/xfs/xfs_trace.h | 32 ++ > > 13 files changed, 769 insertions(+) > > create mode 100644 fs/xfs/libxfs/xfs_verity.c > > create mode 100644 fs/xfs/libxfs/xfs_verity.h > > create mode 100644 fs/xfs/xfs_fsverity.c > > create mode 100644 fs/xfs/xfs_fsverity.h > > > > <snip> > > diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h > > index 5a202706fc4a4..70c5700132b3e 100644 > > --- a/fs/xfs/xfs_inode.h > > +++ b/fs/xfs/xfs_inode.h > > @@ -96,6 +96,9 @@ typedef struct xfs_inode { > > spinlock_t i_ioend_lock; > > struct work_struct i_ioend_work; > > struct list_head i_ioend_list; > > +#ifdef CONFIG_FS_VERITY > > + struct xarray i_merkle_blocks; > > +#endif > > So, is this fine like this or do you plan to change it to per-ag > mapping? I suppose Christoph against adding it to inodes [1] > > [1]: https://lore.kernel.org/linux-xfs/ZfecSzBoVDW5328l@infradead.org/ Still working on it. hch and I have been nitpicking the parent pointers patchset. I think a per-ag rhashtable would work in principle, but I don't know how well it will handle a 128-bit key. --D > > } xfs_inode_t; > > > > static inline bool xfs_inode_on_unlinked_list(const struct xfs_inode *ip) > > @@ -391,6 +394,8 @@ static inline bool xfs_inode_needs_cow_around(struct xfs_inode *ip) > > */ > > #define XFS_IREMAPPING (1U << 15) > > > > +#define XFS_VERITY_CONSTRUCTION (1U << 16) /* merkle tree construction */ > > + > > /* All inode state flags related to inode reclaim. */ > > #define XFS_ALL_IRECLAIM_FLAGS (XFS_IRECLAIMABLE | \ > > XFS_IRECLAIM | \ > > diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c > > index 42a1e1f23d3b3..4e398884c46ae 100644 > > --- a/fs/xfs/xfs_super.c > > +++ b/fs/xfs/xfs_super.c > > @@ -30,6 +30,7 @@ > > #include "xfs_filestream.h" > > #include "xfs_quota.h" > > #include "xfs_sysfs.h" > > +#include "xfs_fsverity.h" > > #include "xfs_ondisk.h" > > #include "xfs_rmap_item.h" > > #include "xfs_refcount_item.h" > > @@ -53,6 +54,7 @@ > > #include <linux/fs_context.h> > > #include <linux/fs_parser.h> > > #include <linux/fsverity.h> > > +#include <linux/iomap.h> > > > > static const struct super_operations xfs_super_operations; > > > > @@ -672,6 +674,8 @@ xfs_fs_destroy_inode( > > ASSERT(!rwsem_is_locked(&inode->i_rwsem)); > > XFS_STATS_INC(ip->i_mount, vn_rele); > > XFS_STATS_INC(ip->i_mount, vn_remove); > > + if (fsverity_active(inode)) > > + xfs_fsverity_cache_drop(ip); > > fsverity_cleanup_inode(inode); > > xfs_inode_mark_reclaimable(ip); > > } > > @@ -1534,6 +1538,9 @@ xfs_fs_fill_super( > > sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ; > > #endif > > sb->s_op = &xfs_super_operations; > > +#ifdef CONFIG_FS_VERITY > > + sb->s_vop = &xfs_fsverity_ops; > > +#endif > > > > /* > > * Delay mount work if the debug hook is set. This is debug > > @@ -1775,10 +1782,20 @@ xfs_fs_fill_super( > > xfs_warn(mp, > > "EXPERIMENTAL parent pointer feature enabled. Use at your own risk!"); > > > > + if (xfs_has_verity(mp)) > > + xfs_alert(mp, > > + "EXPERIMENTAL fsverity feature in use. Use at your own risk!"); > > + > > error = xfs_mountfs(mp); > > if (error) > > goto out_filestream_unmount; > > > > +#ifdef CONFIG_FS_VERITY > > + error = iomap_init_fsverity(mp->m_super); > > + if (error) > > + goto out_unmount; > > +#endif > > + > > root = igrab(VFS_I(mp->m_rootip)); > > if (!root) { > > error = -ENOENT; > > diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h > > index e2992b0115ad2..86a8702c1e27c 100644 > > --- a/fs/xfs/xfs_trace.h > > +++ b/fs/xfs/xfs_trace.h > > @@ -5908,6 +5908,38 @@ TRACE_EVENT(xfs_growfs_check_rtgeom, > > ); > > #endif /* CONFIG_XFS_RT */ > > > > +#ifdef CONFIG_FS_VERITY > > +DECLARE_EVENT_CLASS(xfs_fsverity_cache_class, > > + TP_PROTO(struct xfs_inode *ip, unsigned long key, unsigned long caller_ip), > > + TP_ARGS(ip, key, caller_ip), > > + TP_STRUCT__entry( > > + __field(dev_t, dev) > > + __field(xfs_ino_t, ino) > > + __field(unsigned long, key) > > + __field(void *, caller_ip) > > + ), > > + TP_fast_assign( > > + __entry->dev = ip->i_mount->m_super->s_dev; > > + __entry->ino = ip->i_ino; > > + __entry->key = key; > > + __entry->caller_ip = (void *)caller_ip; > > + ), > > + TP_printk("dev %d:%d ino 0x%llx key 0x%lx caller %pS", > > + MAJOR(__entry->dev), MINOR(__entry->dev), > > + __entry->ino, > > + __entry->key, > > + __entry->caller_ip) > > +) > > + > > +#define DEFINE_XFS_FSVERITY_CACHE_EVENT(name) \ > > +DEFINE_EVENT(xfs_fsverity_cache_class, name, \ > > + TP_PROTO(struct xfs_inode *ip, unsigned long key, unsigned long caller_ip), \ > > + TP_ARGS(ip, key, caller_ip)) > > +DEFINE_XFS_FSVERITY_CACHE_EVENT(xfs_fsverity_cache_load); > > +DEFINE_XFS_FSVERITY_CACHE_EVENT(xfs_fsverity_cache_store); > > +DEFINE_XFS_FSVERITY_CACHE_EVENT(xfs_fsverity_cache_drop); > > +#endif /* CONFIG_XFS_VERITY */ > > + > > #endif /* _TRACE_XFS_H */ > > > > #undef TRACE_INCLUDE_PATH > > > > -- > - Andrey > >
On Tue, Apr 02, 2024 at 09:34:53AM -0700, Darrick J. Wong wrote: > On Tue, Apr 02, 2024 at 10:42:44AM +0200, Andrey Albershteyn wrote: > > On 2024-03-29 17:39:27, Darrick J. Wong wrote: > > > From: Andrey Albershteyn <aalbersh@redhat.com> > > > > > > Add integration with fs-verity. The XFS store fs-verity metadata in > > > the extended file attributes. The metadata consist of verity > > > descriptor and Merkle tree blocks. > > > > > > The descriptor is stored under "vdesc" extended attribute. The > > > Merkle tree blocks are stored under binary indexes which are offsets > > > into the Merkle tree. > > > > > > When fs-verity is enabled on an inode, the XFS_IVERITY_CONSTRUCTION > > > flag is set meaning that the Merkle tree is being build. The > > > initialization ends with storing of verity descriptor and setting > > > inode on-disk flag (XFS_DIFLAG2_VERITY). > > > > > > The verification on read is done in read path of iomap. > > > > > > Signed-off-by: Andrey Albershteyn <aalbersh@redhat.com> > > > Reviewed-by: Darrick J. Wong <djwong@kernel.org> > > > [djwong: replace caching implementation with an xarray, other cleanups] > > > Signed-off-by: Darrick J. Wong <djwong@kernel.org> > > > --- > > > fs/xfs/Makefile | 2 > > > fs/xfs/libxfs/xfs_attr.c | 41 +++ > > > fs/xfs/libxfs/xfs_attr.h | 1 > > > fs/xfs/libxfs/xfs_da_format.h | 14 + > > > fs/xfs/libxfs/xfs_ondisk.h | 3 > > > fs/xfs/libxfs/xfs_verity.c | 58 ++++ > > > fs/xfs/libxfs/xfs_verity.h | 13 + > > > fs/xfs/xfs_fsverity.c | 559 +++++++++++++++++++++++++++++++++++++++++ > > > fs/xfs/xfs_fsverity.h | 20 + > > > fs/xfs/xfs_icache.c | 4 > > > fs/xfs/xfs_inode.h | 5 > > > fs/xfs/xfs_super.c | 17 + > > > fs/xfs/xfs_trace.h | 32 ++ > > > 13 files changed, 769 insertions(+) > > > create mode 100644 fs/xfs/libxfs/xfs_verity.c > > > create mode 100644 fs/xfs/libxfs/xfs_verity.h > > > create mode 100644 fs/xfs/xfs_fsverity.c > > > create mode 100644 fs/xfs/xfs_fsverity.h > > > > > > > > <snip> > > > > diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h > > > index 5a202706fc4a4..70c5700132b3e 100644 > > > --- a/fs/xfs/xfs_inode.h > > > +++ b/fs/xfs/xfs_inode.h > > > @@ -96,6 +96,9 @@ typedef struct xfs_inode { > > > spinlock_t i_ioend_lock; > > > struct work_struct i_ioend_work; > > > struct list_head i_ioend_list; > > > +#ifdef CONFIG_FS_VERITY > > > + struct xarray i_merkle_blocks; > > > +#endif > > > > So, is this fine like this or do you plan to change it to per-ag > > mapping? I suppose Christoph against adding it to inodes [1] > > > > [1]: https://lore.kernel.org/linux-xfs/ZfecSzBoVDW5328l@infradead.org/ > > Still working on it. hch and I have been nitpicking the parent pointers > patchset. I think a per-ag rhashtable would work in principle, but I > don't know how well it will handle a 128-bit key. Update: works fine, and now we don't need to add 16 bytes of overhead to every xfs_inode everywhere. --D > --D > > > > } xfs_inode_t; > > > > > > static inline bool xfs_inode_on_unlinked_list(const struct xfs_inode *ip) > > > @@ -391,6 +394,8 @@ static inline bool xfs_inode_needs_cow_around(struct xfs_inode *ip) > > > */ > > > #define XFS_IREMAPPING (1U << 15) > > > > > > +#define XFS_VERITY_CONSTRUCTION (1U << 16) /* merkle tree construction */ > > > + > > > /* All inode state flags related to inode reclaim. */ > > > #define XFS_ALL_IRECLAIM_FLAGS (XFS_IRECLAIMABLE | \ > > > XFS_IRECLAIM | \ > > > diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c > > > index 42a1e1f23d3b3..4e398884c46ae 100644 > > > --- a/fs/xfs/xfs_super.c > > > +++ b/fs/xfs/xfs_super.c > > > @@ -30,6 +30,7 @@ > > > #include "xfs_filestream.h" > > > #include "xfs_quota.h" > > > #include "xfs_sysfs.h" > > > +#include "xfs_fsverity.h" > > > #include "xfs_ondisk.h" > > > #include "xfs_rmap_item.h" > > > #include "xfs_refcount_item.h" > > > @@ -53,6 +54,7 @@ > > > #include <linux/fs_context.h> > > > #include <linux/fs_parser.h> > > > #include <linux/fsverity.h> > > > +#include <linux/iomap.h> > > > > > > static const struct super_operations xfs_super_operations; > > > > > > @@ -672,6 +674,8 @@ xfs_fs_destroy_inode( > > > ASSERT(!rwsem_is_locked(&inode->i_rwsem)); > > > XFS_STATS_INC(ip->i_mount, vn_rele); > > > XFS_STATS_INC(ip->i_mount, vn_remove); > > > + if (fsverity_active(inode)) > > > + xfs_fsverity_cache_drop(ip); > > > fsverity_cleanup_inode(inode); > > > xfs_inode_mark_reclaimable(ip); > > > } > > > @@ -1534,6 +1538,9 @@ xfs_fs_fill_super( > > > sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ; > > > #endif > > > sb->s_op = &xfs_super_operations; > > > +#ifdef CONFIG_FS_VERITY > > > + sb->s_vop = &xfs_fsverity_ops; > > > +#endif > > > > > > /* > > > * Delay mount work if the debug hook is set. This is debug > > > @@ -1775,10 +1782,20 @@ xfs_fs_fill_super( > > > xfs_warn(mp, > > > "EXPERIMENTAL parent pointer feature enabled. Use at your own risk!"); > > > > > > + if (xfs_has_verity(mp)) > > > + xfs_alert(mp, > > > + "EXPERIMENTAL fsverity feature in use. Use at your own risk!"); > > > + > > > error = xfs_mountfs(mp); > > > if (error) > > > goto out_filestream_unmount; > > > > > > +#ifdef CONFIG_FS_VERITY > > > + error = iomap_init_fsverity(mp->m_super); > > > + if (error) > > > + goto out_unmount; > > > +#endif > > > + > > > root = igrab(VFS_I(mp->m_rootip)); > > > if (!root) { > > > error = -ENOENT; > > > diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h > > > index e2992b0115ad2..86a8702c1e27c 100644 > > > --- a/fs/xfs/xfs_trace.h > > > +++ b/fs/xfs/xfs_trace.h > > > @@ -5908,6 +5908,38 @@ TRACE_EVENT(xfs_growfs_check_rtgeom, > > > ); > > > #endif /* CONFIG_XFS_RT */ > > > > > > +#ifdef CONFIG_FS_VERITY > > > +DECLARE_EVENT_CLASS(xfs_fsverity_cache_class, > > > + TP_PROTO(struct xfs_inode *ip, unsigned long key, unsigned long caller_ip), > > > + TP_ARGS(ip, key, caller_ip), > > > + TP_STRUCT__entry( > > > + __field(dev_t, dev) > > > + __field(xfs_ino_t, ino) > > > + __field(unsigned long, key) > > > + __field(void *, caller_ip) > > > + ), > > > + TP_fast_assign( > > > + __entry->dev = ip->i_mount->m_super->s_dev; > > > + __entry->ino = ip->i_ino; > > > + __entry->key = key; > > > + __entry->caller_ip = (void *)caller_ip; > > > + ), > > > + TP_printk("dev %d:%d ino 0x%llx key 0x%lx caller %pS", > > > + MAJOR(__entry->dev), MINOR(__entry->dev), > > > + __entry->ino, > > > + __entry->key, > > > + __entry->caller_ip) > > > +) > > > + > > > +#define DEFINE_XFS_FSVERITY_CACHE_EVENT(name) \ > > > +DEFINE_EVENT(xfs_fsverity_cache_class, name, \ > > > + TP_PROTO(struct xfs_inode *ip, unsigned long key, unsigned long caller_ip), \ > > > + TP_ARGS(ip, key, caller_ip)) > > > +DEFINE_XFS_FSVERITY_CACHE_EVENT(xfs_fsverity_cache_load); > > > +DEFINE_XFS_FSVERITY_CACHE_EVENT(xfs_fsverity_cache_store); > > > +DEFINE_XFS_FSVERITY_CACHE_EVENT(xfs_fsverity_cache_drop); > > > +#endif /* CONFIG_XFS_VERITY */ > > > + > > > #endif /* _TRACE_XFS_H */ > > > > > > #undef TRACE_INCLUDE_PATH > > > > > > > -- > > - Andrey > > > > >
diff --git a/fs/xfs/Makefile b/fs/xfs/Makefile index 702f2ddc918a1..a4b2f54914a87 100644 --- a/fs/xfs/Makefile +++ b/fs/xfs/Makefile @@ -57,6 +57,7 @@ xfs-y += $(addprefix libxfs/, \ xfs_trans_resv.o \ xfs_trans_space.o \ xfs_types.o \ + xfs_verity.o \ ) # xfs_rtbitmap is shared with libxfs xfs-$(CONFIG_XFS_RT) += $(addprefix libxfs/, \ @@ -142,6 +143,7 @@ xfs-$(CONFIG_XFS_POSIX_ACL) += xfs_acl.o xfs-$(CONFIG_SYSCTL) += xfs_sysctl.o xfs-$(CONFIG_COMPAT) += xfs_ioctl32.o xfs-$(CONFIG_EXPORTFS_BLOCK_OPS) += xfs_pnfs.o +xfs-$(CONFIG_FS_VERITY) += xfs_fsverity.o # notify failure ifeq ($(CONFIG_MEMORY_FAILURE),y) diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c index 931ec563a7460..c3f686411e378 100644 --- a/fs/xfs/libxfs/xfs_attr.c +++ b/fs/xfs/libxfs/xfs_attr.c @@ -27,6 +27,7 @@ #include "xfs_attr_item.h" #include "xfs_xattr.h" #include "xfs_parent.h" +#include "xfs_verity.h" struct kmem_cache *xfs_attr_intent_cache; @@ -1262,6 +1263,43 @@ xfs_attr_removename( goto out_unlock; } +/* + * Retrieve the value stored in the xattr structure under @args->name. + * + * The caller must have initialized @args and must not hold any ILOCKs. + * + * Returns -ENOATTR if the name did not already exist. + */ +int +xfs_attr_getname( + struct xfs_da_args *args) +{ + unsigned int lock_mode; + int error; + + ASSERT(!args->trans); + + error = xfs_trans_alloc_empty(args->dp->i_mount, &args->trans); + if (error) + return error; + + lock_mode = xfs_ilock_attr_map_shared(args->dp); + + /* Make sure the attr fork iext tree is loaded */ + if (xfs_inode_hasattr(args->dp)) { + error = xfs_iread_extents(args->trans, args->dp, XFS_ATTR_FORK); + if (error) + goto out_unlock; + } + + error = xfs_attr_get_ilocked(args); +out_unlock: + xfs_iunlock(args->dp, lock_mode); + xfs_trans_cancel(args->trans); + args->trans = NULL; + return error; +} + /*======================================================================== * External routines when attribute list is inside the inode *========================================================================*/ @@ -1743,6 +1781,9 @@ xfs_attr_namecheck( if (!xfs_attr_check_namespace(attr_flags)) return false; + if (attr_flags & XFS_ATTR_VERITY) + return xfs_verity_namecheck(attr_flags, name, length); + /* * MAXNAMELEN includes the trailing null, but (name/length) leave it * out, so use >= for the length check. diff --git a/fs/xfs/libxfs/xfs_attr.h b/fs/xfs/libxfs/xfs_attr.h index 958bb9e41ddb3..3e43d715bcdd2 100644 --- a/fs/xfs/libxfs/xfs_attr.h +++ b/fs/xfs/libxfs/xfs_attr.h @@ -561,6 +561,7 @@ void xfs_init_attr_trans(struct xfs_da_args *args, struct xfs_trans_res *tres, int xfs_attr_setname(struct xfs_da_args *args, bool rsvd); int xfs_attr_removename(struct xfs_da_args *args, bool rsvd); +int xfs_attr_getname(struct xfs_da_args *args); /* * Check to see if the attr should be upgraded from non-existent or shortform to diff --git a/fs/xfs/libxfs/xfs_da_format.h b/fs/xfs/libxfs/xfs_da_format.h index 8cbda181c2f48..679cf5b4ad4be 100644 --- a/fs/xfs/libxfs/xfs_da_format.h +++ b/fs/xfs/libxfs/xfs_da_format.h @@ -922,4 +922,18 @@ struct xfs_parent_rec { __be32 p_gen; } __packed; +/* + * fs-verity attribute name format + * + * Merkle tree blocks are stored under extended attributes of the inode. The + * name of the attributes are byte offsets into merkle tree. + */ +struct xfs_merkle_key { + __be64 mk_offset; +}; + +/* ondisk xattr name used for the fsverity descriptor */ +#define XFS_VERITY_DESCRIPTOR_NAME "vdesc" +#define XFS_VERITY_DESCRIPTOR_NAME_LEN (sizeof(XFS_VERITY_DESCRIPTOR_NAME) - 1) + #endif /* __XFS_DA_FORMAT_H__ */ diff --git a/fs/xfs/libxfs/xfs_ondisk.h b/fs/xfs/libxfs/xfs_ondisk.h index d46352d60d645..e927bb778ffdc 100644 --- a/fs/xfs/libxfs/xfs_ondisk.h +++ b/fs/xfs/libxfs/xfs_ondisk.h @@ -208,6 +208,9 @@ xfs_check_ondisk_structs(void) XFS_CHECK_VALUE(XFS_DQ_BIGTIME_EXPIRY_MAX << XFS_DQ_BIGTIME_SHIFT, 16299260424LL); + /* fs-verity xattrs */ + XFS_CHECK_STRUCT_SIZE(struct xfs_merkle_key, 8); + XFS_CHECK_VALUE(sizeof(XFS_VERITY_DESCRIPTOR_NAME), 6); } #endif /* __XFS_ONDISK_H */ diff --git a/fs/xfs/libxfs/xfs_verity.c b/fs/xfs/libxfs/xfs_verity.c new file mode 100644 index 0000000000000..bda38b3c19698 --- /dev/null +++ b/fs/xfs/libxfs/xfs_verity.c @@ -0,0 +1,58 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2023 Red Hat, Inc. + */ +#include "xfs.h" +#include "xfs_shared.h" +#include "xfs_format.h" +#include "xfs_da_format.h" +#include "xfs_da_btree.h" +#include "xfs_trans_resv.h" +#include "xfs_mount.h" +#include "xfs_inode.h" +#include "xfs_log_format.h" +#include "xfs_attr.h" +#include "xfs_verity.h" + +/* Set a merkle tree offset in preparation for setting merkle tree attrs. */ +void +xfs_merkle_key_to_disk( + struct xfs_merkle_key *key, + uint64_t offset) +{ + key->mk_offset = cpu_to_be64(offset); +} + +/* Retrieve the merkle tree offset from the attr data. */ +uint64_t +xfs_merkle_key_from_disk( + const void *attr_name, + int namelen) +{ + const struct xfs_merkle_key *key = attr_name; + + ASSERT(namelen == sizeof(struct xfs_merkle_key)); + + return be64_to_cpu(key->mk_offset); +} + +/* Return true if verity attr name is valid. */ +bool +xfs_verity_namecheck( + unsigned int attr_flags, + const void *name, + int namelen) +{ + if (!(attr_flags & XFS_ATTR_VERITY)) + return false; + + /* + * Merkle tree pages are stored under u64 indexes; verity descriptor + * blocks are held in a named attribute. + */ + if (namelen != sizeof(struct xfs_merkle_key) && + namelen != XFS_VERITY_DESCRIPTOR_NAME_LEN) + return false; + + return true; +} diff --git a/fs/xfs/libxfs/xfs_verity.h b/fs/xfs/libxfs/xfs_verity.h new file mode 100644 index 0000000000000..c01cc0678bc04 --- /dev/null +++ b/fs/xfs/libxfs/xfs_verity.h @@ -0,0 +1,13 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2022 Red Hat, Inc. + */ +#ifndef __XFS_VERITY_H__ +#define __XFS_VERITY_H__ + +void xfs_merkle_key_to_disk(struct xfs_merkle_key *key, uint64_t offset); +uint64_t xfs_merkle_key_from_disk(const void *attr_name, int namelen); +bool xfs_verity_namecheck(unsigned int attr_flags, const void *name, + int namelen); + +#endif /* __XFS_VERITY_H__ */ diff --git a/fs/xfs/xfs_fsverity.c b/fs/xfs/xfs_fsverity.c new file mode 100644 index 0000000000000..a4a52575fb3d5 --- /dev/null +++ b/fs/xfs/xfs_fsverity.c @@ -0,0 +1,559 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2023 Red Hat, Inc. + */ +#include "xfs.h" +#include "xfs_shared.h" +#include "xfs_format.h" +#include "xfs_da_format.h" +#include "xfs_da_btree.h" +#include "xfs_trans_resv.h" +#include "xfs_mount.h" +#include "xfs_inode.h" +#include "xfs_log_format.h" +#include "xfs_attr.h" +#include "xfs_verity.h" +#include "xfs_bmap_util.h" +#include "xfs_log_format.h" +#include "xfs_trans.h" +#include "xfs_attr_leaf.h" +#include "xfs_trace.h" +#include "xfs_quota.h" +#include "xfs_fsverity.h" +#include <linux/fsverity.h> + +/* + * Merkle Tree Block Cache + * ======================= + * + * fsverity requires that the filesystem implement caching of ondisk merkle + * tree blocks. XFS stores merkle tree blocks in the extended attribute data, + * which makes it important to keep copies in memory for as long as possible. + * This is performed by allocating the data blob structure defined below, + * passing the data portion of the blob to xfs_attr_get, and later adding the + * data blob to an xarray embedded in the xfs_inode structure. + * + * The xarray structure indexes merkle tree blocks by the offset given to us by + * fsverity, which drastically reduces lookups. First, it eliminating the need + * to walk the xattr structure to find the remote block containing the merkle + * tree block. Second, access to each block in the xattr structure requires a + * lookup in the incore extent btree. + */ +struct xfs_merkle_blob { + /* refcount of this item; the cache holds its own ref */ + refcount_t refcount; + + unsigned long flags; + + /* Pointer to the merkle tree block, which is power-of-2 sized */ + void *data; +}; + +#define XFS_MERKLE_BLOB_VERIFIED_BIT (0) /* fsverity validated this */ + +/* + * Allocate a merkle tree blob object to prepare for reading a merkle tree + * object from disk. + */ +static inline struct xfs_merkle_blob * +xfs_merkle_blob_alloc( + unsigned int blocksize) +{ + struct xfs_merkle_blob *mk; + + mk = kmalloc(sizeof(struct xfs_merkle_blob), GFP_KERNEL); + if (!mk) + return NULL; + + mk->data = kvzalloc(blocksize, GFP_KERNEL); + if (!mk->data) { + kfree(mk); + return NULL; + } + + /* Caller owns this refcount. */ + refcount_set(&mk->refcount, 1); + mk->flags = 0; + return mk; +} + +/* Free a merkle tree blob. */ +static inline void +xfs_merkle_blob_rele( + struct xfs_merkle_blob *mk) +{ + if (refcount_dec_and_test(&mk->refcount)) { + kvfree(mk->data); + kfree(mk); + } +} + +/* Initialize the merkle tree block cache */ +void +xfs_fsverity_cache_init( + struct xfs_inode *ip) +{ + xa_init(&ip->i_merkle_blocks); +} + +/* + * Drop all the merkle tree blocks out of the cache. Caller must ensure that + * there are no active references to cache items. + */ +void +xfs_fsverity_cache_drop( + struct xfs_inode *ip) +{ + XA_STATE(xas, &ip->i_merkle_blocks, 0); + struct xfs_merkle_blob *mk; + unsigned long flags; + + xas_lock_irqsave(&xas, flags); + xas_for_each(&xas, mk, ULONG_MAX) { + ASSERT(refcount_read(&mk->refcount) == 1); + + trace_xfs_fsverity_cache_drop(ip, xas.xa_index, _RET_IP_); + + xas_store(&xas, NULL); + xfs_merkle_blob_rele(mk); + } + xas_unlock_irqrestore(&xas, flags); +} + +/* Destroy the merkle tree block cache */ +void +xfs_fsverity_cache_destroy( + struct xfs_inode *ip) +{ + ASSERT(xa_empty(&ip->i_merkle_blocks)); + + /* + * xa_destroy calls xas_lock from rcu freeing softirq context, so + * we must use xa*_lock_irqsave. + */ + xa_destroy(&ip->i_merkle_blocks); +} + +/* Return a cached merkle tree block, or NULL. */ +static struct xfs_merkle_blob * +xfs_fsverity_cache_load( + struct xfs_inode *ip, + unsigned long key) +{ + XA_STATE(xas, &ip->i_merkle_blocks, key); + struct xfs_merkle_blob *mk; + + /* Look up the cached item and try to get an active ref. */ + rcu_read_lock(); + do { + mk = xas_load(&xas); + if (xa_is_zero(mk)) + mk = NULL; + } while (xas_retry(&xas, mk) || + (mk && !refcount_inc_not_zero(&mk->refcount))); + rcu_read_unlock(); + + if (!mk) + return NULL; + + trace_xfs_fsverity_cache_load(ip, key, _RET_IP_); + return mk; +} + +/* + * Try to store a merkle tree block in the cache with the given key. + * + * If the merkle tree block is not already in the cache, the given block @mk + * will be added to the cache and returned. The caller retains its active + * reference to @mk. + * + * If there was already a merkle block in the cache, it will be returned to + * the caller with an active reference. @mk will be untouched. + */ +static struct xfs_merkle_blob * +xfs_fsverity_cache_store( + struct xfs_inode *ip, + unsigned long key, + struct xfs_merkle_blob *mk) +{ + struct xfs_merkle_blob *old; + unsigned long flags; + + trace_xfs_fsverity_cache_store(ip, key, _RET_IP_); + + /* + * Either replace a NULL entry with mk, or take an active ref to + * whatever's currently there. + */ + xa_lock_irqsave(&ip->i_merkle_blocks, flags); + do { + old = __xa_cmpxchg(&ip->i_merkle_blocks, key, NULL, mk, + GFP_KERNEL); + } while (old && !refcount_inc_not_zero(&old->refcount)); + xa_unlock_irqrestore(&ip->i_merkle_blocks, flags); + + if (old == NULL) { + /* + * There was no previous value. @mk is now live in the cache. + * Bump the active refcount to transfer ownership to the cache + * and return @mk to the caller. + */ + refcount_inc(&mk->refcount); + return mk; + } + + /* + * We obtained an active reference to a previous value in the cache. + * Return it to the caller. + */ + return old; +} + +/* + * Initialize an args structure to load or store the fsverity descriptor. + * Caller must ensure @args is zeroed except for value and valuelen. + */ +static inline void +xfs_fsverity_init_vdesc_args( + struct xfs_inode *ip, + struct xfs_da_args *args) +{ + args->geo = ip->i_mount->m_attr_geo; + args->whichfork = XFS_ATTR_FORK, + args->attr_filter = XFS_ATTR_VERITY; + args->op_flags = XFS_DA_OP_OKNOENT; + args->dp = ip; + args->owner = ip->i_ino; + args->name = XFS_VERITY_DESCRIPTOR_NAME; + args->namelen = XFS_VERITY_DESCRIPTOR_NAME_LEN; + xfs_attr_sethash(args); +} + +/* + * Initialize an args structure to load or store a merkle tree block. + * Caller must ensure @args is zeroed except for value and valuelen. + */ +static inline void +xfs_fsverity_init_merkle_args( + struct xfs_inode *ip, + struct xfs_merkle_key *key, + uint64_t merkleoff, + struct xfs_da_args *args) +{ + xfs_merkle_key_to_disk(key, merkleoff); + args->geo = ip->i_mount->m_attr_geo; + args->whichfork = XFS_ATTR_FORK, + args->attr_filter = XFS_ATTR_VERITY; + args->op_flags = XFS_DA_OP_OKNOENT; + args->dp = ip; + args->owner = ip->i_ino; + args->name = (const uint8_t *)key; + args->namelen = sizeof(struct xfs_merkle_key); + xfs_attr_sethash(args); +} + +/* Delete the verity descriptor. */ +static int +xfs_fsverity_delete_descriptor( + struct xfs_inode *ip) +{ + struct xfs_da_args args = { }; + + xfs_fsverity_init_vdesc_args(ip, &args); + return xfs_attr_removename(&args, false); +} + +/* Delete a merkle tree block. */ +static int +xfs_fsverity_delete_merkle_block( + struct xfs_inode *ip, + u64 offset) +{ + struct xfs_merkle_key name; + struct xfs_da_args args = { }; + + xfs_fsverity_init_merkle_args(ip, &name, offset, &args); + return xfs_attr_removename(&args, false); +} + +/* Retrieve the verity descriptor. */ +static int +xfs_fsverity_get_descriptor( + struct inode *inode, + void *buf, + size_t buf_size) +{ + struct xfs_inode *ip = XFS_I(inode); + struct xfs_da_args args = { + .value = buf, + .valuelen = buf_size, + }; + int error = 0; + + /* + * The fact that (returned attribute size) == (provided buf_size) is + * checked by xfs_attr_copy_value() (returns -ERANGE). No descriptor + * is treated as a short read so that common fsverity code will + * complain. + */ + xfs_fsverity_init_vdesc_args(ip, &args); + error = xfs_attr_getname(&args); + if (error == -ENOATTR) + return 0; + if (error) + return error; + + return args.valuelen; +} + +/* + * Clear out old fsverity metadata before we start building a new one. This + * could happen if, say, we crashed while building fsverity data. + */ +static int +xfs_fsverity_delete_stale_metadata( + struct xfs_inode *ip, + u64 new_tree_size, + unsigned int tree_blocksize) +{ + u64 offset; + int error = 0; + + /* + * Delete as many merkle tree blocks in increasing blkno order until we + * don't find any more. That ought to be good enough for avoiding + * dead bloat without excessive runtime. + */ + for (offset = new_tree_size; !error; offset += tree_blocksize) { + if (fatal_signal_pending(current)) + return -EINTR; + error = xfs_fsverity_delete_merkle_block(ip, offset); + if (error) + break; + } + + return error != -ENOATTR ? error : 0; +} + +/* Prepare to enable fsverity by clearing old metadata. */ +static int +xfs_fsverity_begin_enable( + struct file *filp, + u64 merkle_tree_size, + unsigned int tree_blocksize) +{ + struct inode *inode = file_inode(filp); + struct xfs_inode *ip = XFS_I(inode); + int error; + + xfs_assert_ilocked(ip, XFS_IOLOCK_EXCL); + + if (IS_DAX(inode)) + return -EINVAL; + + if (xfs_iflags_test_and_set(ip, XFS_VERITY_CONSTRUCTION)) + return -EBUSY; + + error = xfs_qm_dqattach(ip); + if (error) + return error; + + return xfs_fsverity_delete_stale_metadata(ip, merkle_tree_size, + tree_blocksize); +} + +/* Try to remove all the fsverity metadata after a failed enablement. */ +static int +xfs_fsverity_delete_metadata( + struct xfs_inode *ip, + u64 merkle_tree_size, + unsigned int tree_blocksize) +{ + u64 offset; + int error; + + if (!merkle_tree_size) + return 0; + + for (offset = 0; offset < merkle_tree_size; offset += tree_blocksize) { + if (fatal_signal_pending(current)) + return -EINTR; + error = xfs_fsverity_delete_merkle_block(ip, offset); + if (error == -ENOATTR) + error = 0; + if (error) + return error; + } + + error = xfs_fsverity_delete_descriptor(ip); + return error != -ENOATTR ? error : 0; +} + +/* Complete (or fail) the process of enabling fsverity. */ +static int +xfs_fsverity_end_enable( + struct file *filp, + const void *desc, + size_t desc_size, + u64 merkle_tree_size, + unsigned int tree_blocksize) +{ + struct xfs_da_args args = { + .value = (void *)desc, + .valuelen = desc_size, + }; + struct inode *inode = file_inode(filp); + struct xfs_inode *ip = XFS_I(inode); + struct xfs_mount *mp = ip->i_mount; + struct xfs_trans *tp; + int error = 0; + + xfs_assert_ilocked(ip, XFS_IOLOCK_EXCL); + + /* fs-verity failed, just cleanup */ + if (desc == NULL) + goto out; + + xfs_fsverity_init_vdesc_args(ip, &args); + error = xfs_attr_setname(&args, false); + if (error) + goto out; + + /* Set fsverity inode flag */ + error = xfs_trans_alloc_inode(ip, &M_RES(mp)->tr_ichange, + 0, 0, false, &tp); + if (error) + goto out; + + /* + * Ensure that we've persisted the verity information before we enable + * it on the inode and tell the caller we have sealed the inode. + */ + ip->i_diflags2 |= XFS_DIFLAG2_VERITY; + + xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); + xfs_trans_set_sync(tp); + + error = xfs_trans_commit(tp); + xfs_iunlock(ip, XFS_ILOCK_EXCL); + + if (!error) + inode->i_flags |= S_VERITY; + +out: + if (error) { + int error2; + + error2 = xfs_fsverity_delete_metadata(ip, + merkle_tree_size, tree_blocksize); + if (error2) + xfs_alert(ip->i_mount, + "ino 0x%llx failed to clean up new fsverity metadata, err %d", + ip->i_ino, error2); + } + + xfs_iflags_clear(ip, XFS_VERITY_CONSTRUCTION); + return error; +} + +/* Retrieve a merkle tree block. */ +static int +xfs_fsverity_read_merkle( + const struct fsverity_readmerkle *req, + struct fsverity_blockbuf *block) +{ + struct xfs_inode *ip = XFS_I(req->inode); + struct xfs_merkle_key name; + struct xfs_da_args args = { + .valuelen = block->size, + }; + struct xfs_merkle_blob *mk, *new_mk; + unsigned long key = block->offset >> req->log_blocksize; + int error; + + ASSERT(block->offset >> req->log_blocksize <= ULONG_MAX); + + /* Is the block already cached? */ + mk = xfs_fsverity_cache_load(ip, key); + if (mk) + goto out_hit; + + new_mk = xfs_merkle_blob_alloc(block->size); + if (!new_mk) + return -ENOMEM; + args.value = new_mk->data; + + /* Read the block in from disk and try to store it in the cache. */ + xfs_fsverity_init_merkle_args(ip, &name, block->offset, &args); + error = xfs_attr_getname(&args); + if (error) + goto out_new_mk; + + if (!args.valuelen) { + error = -ENODATA; + goto out_new_mk; + } + + mk = xfs_fsverity_cache_store(ip, key, new_mk); + if (mk != new_mk) { + /* + * We raced with another thread to populate the cache and lost. + * Free the new cache blob and continue with the existing one. + */ + xfs_merkle_blob_rele(new_mk); + } + +out_hit: + block->kaddr = (void *)mk->data; + block->context = mk; + block->verified = test_bit(XFS_MERKLE_BLOB_VERIFIED_BIT, &mk->flags); + + return 0; + +out_new_mk: + xfs_merkle_blob_rele(new_mk); + return error; +} + +/* Write a merkle tree block. */ +static int +xfs_fsverity_write_merkle( + const struct fsverity_writemerkle *req, + const void *buf, + u64 pos, + unsigned int size) +{ + struct inode *inode = req->inode; + struct xfs_inode *ip = XFS_I(inode); + struct xfs_merkle_key name; + struct xfs_da_args args = { + .value = (void *)buf, + .valuelen = size, + }; + + xfs_fsverity_init_merkle_args(ip, &name, pos, &args); + return xfs_attr_setname(&args, false); +} + +/* Drop a cached merkle tree block.. */ +static void +xfs_fsverity_drop_merkle( + struct fsverity_blockbuf *block) +{ + struct xfs_merkle_blob *mk = block->context; + + if (block->verified) + set_bit(XFS_MERKLE_BLOB_VERIFIED_BIT, &mk->flags); + xfs_merkle_blob_rele(mk); + block->kaddr = NULL; + block->context = NULL; +} + +const struct fsverity_operations xfs_fsverity_ops = { + .begin_enable_verity = xfs_fsverity_begin_enable, + .end_enable_verity = xfs_fsverity_end_enable, + .get_verity_descriptor = xfs_fsverity_get_descriptor, + .read_merkle_tree_block = xfs_fsverity_read_merkle, + .write_merkle_tree_block = xfs_fsverity_write_merkle, + .drop_merkle_tree_block = xfs_fsverity_drop_merkle, +}; diff --git a/fs/xfs/xfs_fsverity.h b/fs/xfs/xfs_fsverity.h new file mode 100644 index 0000000000000..277a9f856f518 --- /dev/null +++ b/fs/xfs/xfs_fsverity.h @@ -0,0 +1,20 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2022 Red Hat, Inc. + */ +#ifndef __XFS_FSVERITY_H__ +#define __XFS_FSVERITY_H__ + +#ifdef CONFIG_FS_VERITY +void xfs_fsverity_cache_init(struct xfs_inode *ip); +void xfs_fsverity_cache_drop(struct xfs_inode *ip); +void xfs_fsverity_cache_destroy(struct xfs_inode *ip); + +extern const struct fsverity_operations xfs_fsverity_ops; +#else +# define xfs_fsverity_cache_init(ip) ((void)0) +# define xfs_fsverity_cache_drop(ip) ((void)0) +# define xfs_fsverity_cache_destroy(ip) ((void)0) +#endif /* CONFIG_FS_VERITY */ + +#endif /* __XFS_FSVERITY_H__ */ diff --git a/fs/xfs/xfs_icache.c b/fs/xfs/xfs_icache.c index 01bbdbec6663f..0757062c318d0 100644 --- a/fs/xfs/xfs_icache.c +++ b/fs/xfs/xfs_icache.c @@ -28,6 +28,7 @@ #include "xfs_da_format.h" #include "xfs_dir2.h" #include "xfs_imeta.h" +#include "xfs_fsverity.h" #include <linux/iversion.h> @@ -118,6 +119,7 @@ xfs_inode_alloc( spin_lock_init(&ip->i_ioend_lock); ip->i_next_unlinked = NULLAGINO; ip->i_prev_unlinked = 0; + xfs_fsverity_cache_init(ip); return ip; } @@ -129,6 +131,8 @@ xfs_inode_free_callback( struct inode *inode = container_of(head, struct inode, i_rcu); struct xfs_inode *ip = XFS_I(inode); + xfs_fsverity_cache_destroy(ip); + switch (VFS_I(ip)->i_mode & S_IFMT) { case S_IFREG: case S_IFDIR: diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h index 5a202706fc4a4..70c5700132b3e 100644 --- a/fs/xfs/xfs_inode.h +++ b/fs/xfs/xfs_inode.h @@ -96,6 +96,9 @@ typedef struct xfs_inode { spinlock_t i_ioend_lock; struct work_struct i_ioend_work; struct list_head i_ioend_list; +#ifdef CONFIG_FS_VERITY + struct xarray i_merkle_blocks; +#endif } xfs_inode_t; static inline bool xfs_inode_on_unlinked_list(const struct xfs_inode *ip) @@ -391,6 +394,8 @@ static inline bool xfs_inode_needs_cow_around(struct xfs_inode *ip) */ #define XFS_IREMAPPING (1U << 15) +#define XFS_VERITY_CONSTRUCTION (1U << 16) /* merkle tree construction */ + /* All inode state flags related to inode reclaim. */ #define XFS_ALL_IRECLAIM_FLAGS (XFS_IRECLAIMABLE | \ XFS_IRECLAIM | \ diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c index 42a1e1f23d3b3..4e398884c46ae 100644 --- a/fs/xfs/xfs_super.c +++ b/fs/xfs/xfs_super.c @@ -30,6 +30,7 @@ #include "xfs_filestream.h" #include "xfs_quota.h" #include "xfs_sysfs.h" +#include "xfs_fsverity.h" #include "xfs_ondisk.h" #include "xfs_rmap_item.h" #include "xfs_refcount_item.h" @@ -53,6 +54,7 @@ #include <linux/fs_context.h> #include <linux/fs_parser.h> #include <linux/fsverity.h> +#include <linux/iomap.h> static const struct super_operations xfs_super_operations; @@ -672,6 +674,8 @@ xfs_fs_destroy_inode( ASSERT(!rwsem_is_locked(&inode->i_rwsem)); XFS_STATS_INC(ip->i_mount, vn_rele); XFS_STATS_INC(ip->i_mount, vn_remove); + if (fsverity_active(inode)) + xfs_fsverity_cache_drop(ip); fsverity_cleanup_inode(inode); xfs_inode_mark_reclaimable(ip); } @@ -1534,6 +1538,9 @@ xfs_fs_fill_super( sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ; #endif sb->s_op = &xfs_super_operations; +#ifdef CONFIG_FS_VERITY + sb->s_vop = &xfs_fsverity_ops; +#endif /* * Delay mount work if the debug hook is set. This is debug @@ -1775,10 +1782,20 @@ xfs_fs_fill_super( xfs_warn(mp, "EXPERIMENTAL parent pointer feature enabled. Use at your own risk!"); + if (xfs_has_verity(mp)) + xfs_alert(mp, + "EXPERIMENTAL fsverity feature in use. Use at your own risk!"); + error = xfs_mountfs(mp); if (error) goto out_filestream_unmount; +#ifdef CONFIG_FS_VERITY + error = iomap_init_fsverity(mp->m_super); + if (error) + goto out_unmount; +#endif + root = igrab(VFS_I(mp->m_rootip)); if (!root) { error = -ENOENT; diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h index e2992b0115ad2..86a8702c1e27c 100644 --- a/fs/xfs/xfs_trace.h +++ b/fs/xfs/xfs_trace.h @@ -5908,6 +5908,38 @@ TRACE_EVENT(xfs_growfs_check_rtgeom, ); #endif /* CONFIG_XFS_RT */ +#ifdef CONFIG_FS_VERITY +DECLARE_EVENT_CLASS(xfs_fsverity_cache_class, + TP_PROTO(struct xfs_inode *ip, unsigned long key, unsigned long caller_ip), + TP_ARGS(ip, key, caller_ip), + TP_STRUCT__entry( + __field(dev_t, dev) + __field(xfs_ino_t, ino) + __field(unsigned long, key) + __field(void *, caller_ip) + ), + TP_fast_assign( + __entry->dev = ip->i_mount->m_super->s_dev; + __entry->ino = ip->i_ino; + __entry->key = key; + __entry->caller_ip = (void *)caller_ip; + ), + TP_printk("dev %d:%d ino 0x%llx key 0x%lx caller %pS", + MAJOR(__entry->dev), MINOR(__entry->dev), + __entry->ino, + __entry->key, + __entry->caller_ip) +) + +#define DEFINE_XFS_FSVERITY_CACHE_EVENT(name) \ +DEFINE_EVENT(xfs_fsverity_cache_class, name, \ + TP_PROTO(struct xfs_inode *ip, unsigned long key, unsigned long caller_ip), \ + TP_ARGS(ip, key, caller_ip)) +DEFINE_XFS_FSVERITY_CACHE_EVENT(xfs_fsverity_cache_load); +DEFINE_XFS_FSVERITY_CACHE_EVENT(xfs_fsverity_cache_store); +DEFINE_XFS_FSVERITY_CACHE_EVENT(xfs_fsverity_cache_drop); +#endif /* CONFIG_XFS_VERITY */ + #endif /* _TRACE_XFS_H */ #undef TRACE_INCLUDE_PATH