From patchwork Tue Apr 30 03:30:06 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Darrick J. Wong" X-Patchwork-Id: 13648066 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CEFFADDA6; Tue, 30 Apr 2024 03:30:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714447806; cv=none; b=L+N3Zb3YaQfCx473HkHfH64z6tiqebRDmVENZGjXZA6Ws95vblh/5d+eHkVGkY6HX9MmQwlC56/cZawOPT/JRU7gYjhUjgm33yDn1Mk6TJq8MI/T49QPYjHcAitzUDilC/oJfO7wxAkwb/jcF0xV8/DfpU6FZHlzQwhlwEoKTrY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714447806; c=relaxed/simple; bh=onh5fSUvb4T8Q52MEVObwn5ZKikQJKXx88H4RpZBu4o=; h=Date:Subject:From:To:Cc:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=Ox4vbL/iMf35SuV9uAXos/kL/+Q1RC1AWmeFDv3kT7/ERjJ5n2sfQ4l4gd9ja6Xv2+BDWPJ8m5H55pwY95sTMaEL8B8NhUySSBgTN5ANSKBKWitcDCglJS3nxfeWgEE/aADCrTcMelfgLGP28thlGvjl3ENDag3HiXtablQpm9s= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=UdVpHkU8; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="UdVpHkU8" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A4E10C116B1; Tue, 30 Apr 2024 03:30:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1714447806; bh=onh5fSUvb4T8Q52MEVObwn5ZKikQJKXx88H4RpZBu4o=; h=Date:Subject:From:To:Cc:In-Reply-To:References:From; b=UdVpHkU82ramTSfxXMcTGZuy6/GDspmKt4gfhWH7P0YIyikDqZ8382L7UssY/Uuku upQZep+xRJqfza3wHMloqdIcAqKxgKQxTi5BHCZDTP+QHNFIVl/7NmkmNmaDV5RC1/ OucmBDklvo2Z7nRpzJCcDW/f5+SyrIHFpT8PTL8m+I/liXWLn2gdKcyHP4UmlnAXgl 8B7tVcVFCfNipxFsY4HiKkndtEWkBVxNRKWa3Fmw3FFCPSRbVu1NTQ+JM21OinDHGP Gec1ZATv9OWB/S5X9AE/PIqIK9BQFWE3iDbWueaKG1/JXvbCNaFvozMlgEgmmVV0y/ PCgpnHConkwFQ== Date: Mon, 29 Apr 2024 20:30:06 -0700 Subject: [PATCH 23/26] xfs: teach online repair to evaluate fsverity xattrs From: "Darrick J. Wong" To: aalbersh@redhat.com, ebiggers@kernel.org, djwong@kernel.org Cc: linux-xfs@vger.kernel.org, alexl@redhat.com, walters@verbum.org, fsverity@lists.linux.dev, linux-fsdevel@vger.kernel.org Message-ID: <171444680757.957659.8130677930415663024.stgit@frogsfrogsfrogs> In-Reply-To: <171444680291.957659.15782417454902691461.stgit@frogsfrogsfrogs> References: <171444680291.957659.15782417454902691461.stgit@frogsfrogsfrogs> User-Agent: StGit/0.19 Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Darrick J. Wong Teach online repair to check for unused fsverity metadata and purge it on reconstruction. Signed-off-by: Darrick J. Wong Reviewed-by: Andrey Albershteyn --- fs/xfs/scrub/attr.c | 138 ++++++++++++++++++++++++++++++++++++++++++++ fs/xfs/scrub/attr.h | 6 ++ fs/xfs/scrub/attr_repair.c | 51 ++++++++++++++++ fs/xfs/scrub/trace.c | 1 fs/xfs/scrub/trace.h | 31 ++++++++++ 5 files changed, 226 insertions(+), 1 deletion(-) diff --git a/fs/xfs/scrub/attr.c b/fs/xfs/scrub/attr.c index b1448832ae6ba..f5fd7424bad1a 100644 --- a/fs/xfs/scrub/attr.c +++ b/fs/xfs/scrub/attr.c @@ -18,6 +18,7 @@ #include "xfs_attr_leaf.h" #include "xfs_attr_sf.h" #include "xfs_parent.h" +#include "xfs_verity.h" #include "scrub/scrub.h" #include "scrub/common.h" #include "scrub/dabtree.h" @@ -126,6 +127,47 @@ xchk_setup_xattr_buf( return 0; } +#ifdef CONFIG_FS_VERITY +/* + * Obtain merkle tree geometry information for a verity file so that we can + * perform sanity checks of the fsverity xattrs. + */ +STATIC int +xchk_xattr_setup_verity( + struct xfs_scrub *sc) +{ + struct xchk_xattr_buf *ab; + int error; + + /* + * Drop the ILOCK and the transaction because loading the fsverity + * metadata will call into the xattr code. S_VERITY is enabled with + * IOLOCK_EXCL held, so it should not change here. + */ + xchk_iunlock(sc, XFS_ILOCK_EXCL); + xchk_trans_cancel(sc); + + error = xchk_setup_xattr_buf(sc, 0); + if (error) + return error; + + ab = sc->buf; + error = xchk_inode_setup_verity(sc, &ab->merkle_blocksize, + &ab->merkle_tree_size); + if (error) + return error; + + error = xchk_trans_alloc(sc, 0); + if (error) + return error; + + xchk_ilock(sc, XFS_ILOCK_EXCL); + return 0; +} +#else +# define xchk_xattr_setup_verity(...) (0) +#endif /* CONFIG_FS_VERITY */ + /* Set us up to scrub an inode's extended attributes. */ int xchk_setup_xattr( @@ -150,9 +192,89 @@ xchk_setup_xattr( return error; } - return xchk_setup_inode_contents(sc, 0); + error = xchk_setup_inode_contents(sc, 0); + if (error) + return error; + + if (IS_VERITY(VFS_I(sc->ip))) { + error = xchk_xattr_setup_verity(sc); + if (error) + return error; + } + + return error; } +#ifdef CONFIG_FS_VERITY +/* Check the merkle tree xattrs. */ +STATIC void +xchk_xattr_verity( + struct xfs_scrub *sc, + xfs_dablk_t blkno, + const unsigned char *name, + unsigned int namelen, + unsigned int valuelen) +{ + struct xchk_xattr_buf *ab = sc->buf; + + /* Non-verity filesystems should never have verity xattrs. */ + if (!xfs_has_verity(sc->mp)) { + xchk_fblock_set_corrupt(sc, XFS_ATTR_FORK, blkno); + return; + } + + /* + * Any verity metadata on a non-verity file are leftovers from a + * previous attempt to enable verity. + */ + if (!IS_VERITY(VFS_I(sc->ip))) { + xchk_ino_set_preen(sc, sc->ip->i_ino); + return; + } + + /* Zero blocksize occurs if we couldn't load the merkle tree data. */ + if (ab->merkle_blocksize == 0) + return; + + switch (namelen) { + case sizeof(struct xfs_merkle_key): + /* Oversized blocks are not allowed */ + if (valuelen > ab->merkle_blocksize) { + xchk_fblock_set_corrupt(sc, XFS_ATTR_FORK, blkno); + return; + } + break; + case XFS_VERITY_DESCRIPTOR_NAME_LEN: + /* Has to match the descriptor xattr name */ + if (memcmp(name, XFS_VERITY_DESCRIPTOR_NAME, namelen)) + xchk_fblock_set_corrupt(sc, XFS_ATTR_FORK, blkno); + return; + default: + xchk_fblock_set_corrupt(sc, XFS_ATTR_FORK, blkno); + return; + } + + /* + * Merkle tree blocks beyond the end of the tree are leftovers from + * a previous failed attempt to enable verity. + */ + if (xfs_merkle_key_from_disk(name, namelen) >= ab->merkle_tree_size) + xchk_ino_set_preen(sc, sc->ip->i_ino); +} +#else +static void +xchk_xattr_verity( + struct xfs_scrub *sc, + xfs_dablk_t blkno, + const unsigned char *name, + unsigned int namelen, + unsigned int valuelen) +{ + /* Should never see verity xattrs when verity is not enabled. */ + xchk_fblock_set_corrupt(sc, XFS_ATTR_FORK, blkno); +} +#endif /* CONFIG_FS_VERITY */ + /* Extended Attributes */ /* @@ -216,6 +338,13 @@ xchk_xattr_actor( return -ECANCELED; } + /* Check verity xattr geometry */ + if (attr_flags & XFS_ATTR_VERITY) { + xchk_xattr_verity(sc, args.blkno, name, namelen, valuelen); + if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT) + return -ECANCELED; + } + /* * Try to allocate enough memory to extract the attr value. If that * doesn't work, return -EDEADLOCK as a signal to try again with a @@ -653,6 +782,13 @@ xchk_xattr( if (xchk_inode_verity_broken(sc->ip)) xchk_set_incomplete(sc); + /* + * If this is a verity file that won't activate, we cannot check the + * merkle tree geometry. + */ + if (xchk_inode_verity_broken(sc->ip)) + xchk_set_incomplete(sc); + /* Allocate memory for xattr checking. */ error = xchk_setup_xattr_buf(sc, 0); if (error == -ENOMEM) diff --git a/fs/xfs/scrub/attr.h b/fs/xfs/scrub/attr.h index 7db58af56646b..40b8c12384f55 100644 --- a/fs/xfs/scrub/attr.h +++ b/fs/xfs/scrub/attr.h @@ -22,6 +22,12 @@ struct xchk_xattr_buf { /* Memory buffer used to extract xattr values. */ void *value; size_t value_sz; + +#ifdef CONFIG_FS_VERITY + /* Geometry of the merkle tree attached to this verity file. */ + u64 merkle_tree_size; + unsigned int merkle_blocksize; +#endif }; bool xchk_xattr_set_map(struct xfs_scrub *sc, unsigned long *map, diff --git a/fs/xfs/scrub/attr_repair.c b/fs/xfs/scrub/attr_repair.c index c7eb94069cafc..ff38c563a090b 100644 --- a/fs/xfs/scrub/attr_repair.c +++ b/fs/xfs/scrub/attr_repair.c @@ -29,6 +29,7 @@ #include "xfs_exchrange.h" #include "xfs_acl.h" #include "xfs_parent.h" +#include "xfs_verity.h" #include "scrub/xfs_scrub.h" #include "scrub/scrub.h" #include "scrub/common.h" @@ -155,6 +156,44 @@ xrep_setup_xattr( return xrep_tempfile_create(sc, S_IFREG); } +#ifdef CONFIG_FS_VERITY +static int +xrep_xattr_want_salvage_verity( + struct xrep_xattr *rx, + const void *name, + int namelen, + int valuelen) +{ + struct xchk_xattr_buf *ab = rx->sc->buf; + + if (!xfs_has_verity(rx->sc->mp)) + return false; + if (!IS_VERITY(VFS_I(rx->sc->ip))) + return false; + + switch (namelen) { + case sizeof(struct xfs_merkle_key): + /* Oversized blocks are not allowed */ + if (valuelen > ab->merkle_blocksize) + return false; + break; + case XFS_VERITY_DESCRIPTOR_NAME_LEN: + /* Has to match the descriptor xattr name */ + return !memcmp(name, XFS_VERITY_DESCRIPTOR_NAME, namelen); + default: + return false; + } + + /* + * Merkle tree blocks beyond the end of the tree are leftovers from + * a previous failed attempt to enable verity. + */ + return xfs_merkle_key_from_disk(name, namelen) < ab->merkle_tree_size; +} +#else +# define xrep_xattr_want_salvage_verity(...) (false) +#endif /* CONFIG_FS_VERITY */ + /* * Decide if we want to salvage this attribute. We don't bother with * incomplete or oversized keys or values. The @value parameter can be null @@ -179,6 +218,9 @@ xrep_xattr_want_salvage( return false; if (attr_flags & XFS_ATTR_PARENT) return xfs_parent_valuecheck(rx->sc->mp, value, valuelen); + if (attr_flags & XFS_ATTR_VERITY) + return xrep_xattr_want_salvage_verity(rx, name, namelen, + valuelen); return true; } @@ -212,6 +254,11 @@ xrep_xattr_salvage_key( trace_xrep_xattr_salvage_pptr(rx->sc->ip, flags, name, key.namelen, value, valuelen); + } else if (flags & XFS_ATTR_VERITY) { + key.namelen = namelen; + + trace_xrep_xattr_salvage_verity(rx->sc->ip, flags, name, + key.namelen, value, valuelen); } else { while (i < namelen && name[i] != 0) i++; @@ -663,6 +710,10 @@ xrep_xattr_insert_rec( ab->name, key->namelen, ab->value, key->valuelen); args.op_flags |= XFS_DA_OP_LOGGED; + } else if (key->flags & XFS_ATTR_VERITY) { + trace_xrep_xattr_insert_verity(rx->sc->ip, key->flags, + ab->name, key->namelen, ab->value, + key->valuelen); } else { trace_xrep_xattr_insert_rec(rx->sc->tempip, key->flags, ab->name, key->namelen, key->valuelen); diff --git a/fs/xfs/scrub/trace.c b/fs/xfs/scrub/trace.c index 6d8acb2f63d8a..69c234f2a4b32 100644 --- a/fs/xfs/scrub/trace.c +++ b/fs/xfs/scrub/trace.c @@ -22,6 +22,7 @@ #include "xfs_parent.h" #include "xfs_imeta.h" #include "xfs_rtgroup.h" +#include "xfs_verity.h" #include "scrub/scrub.h" #include "scrub/xfile.h" #include "scrub/xfarray.h" diff --git a/fs/xfs/scrub/trace.h b/fs/xfs/scrub/trace.h index c43d02f9afade..c41598456dfcf 100644 --- a/fs/xfs/scrub/trace.h +++ b/fs/xfs/scrub/trace.h @@ -3072,6 +3072,37 @@ DEFINE_EVENT(xrep_pptr_salvage_class, name, \ DEFINE_XREP_PPTR_SALVAGE_EVENT(xrep_xattr_salvage_pptr); DEFINE_XREP_PPTR_SALVAGE_EVENT(xrep_xattr_insert_pptr); +DECLARE_EVENT_CLASS(xrep_verity_salvage_class, + TP_PROTO(struct xfs_inode *ip, unsigned int flags, const void *name, + unsigned int namelen, const void *value, unsigned int valuelen), + TP_ARGS(ip, flags, name, namelen, value, valuelen), + TP_STRUCT__entry( + __field(dev_t, dev) + __field(xfs_ino_t, ino) + __field(unsigned long long, merkle_off) + ), + TP_fast_assign( + __entry->dev = ip->i_mount->m_super->s_dev; + __entry->ino = ip->i_ino; + if (namelen == sizeof(struct xfs_merkle_key)) + __entry->merkle_off = xfs_merkle_key_from_disk(name, + namelen); + else + __entry->merkle_off = -1ULL; + ), + TP_printk("dev %d:%d ino 0x%llx merkle_off 0x%llx", + MAJOR(__entry->dev), MINOR(__entry->dev), + __entry->ino, + __entry->merkle_off) +) +#define DEFINE_XREP_VERITY_SALVAGE_EVENT(name) \ +DEFINE_EVENT(xrep_verity_salvage_class, name, \ + TP_PROTO(struct xfs_inode *ip, unsigned int flags, const void *name, \ + unsigned int namelen, const void *value, unsigned int valuelen), \ + TP_ARGS(ip, flags, name, namelen, value, valuelen)) +DEFINE_XREP_VERITY_SALVAGE_EVENT(xrep_xattr_salvage_verity); +DEFINE_XREP_VERITY_SALVAGE_EVENT(xrep_xattr_insert_verity); + TRACE_EVENT(xrep_xattr_class, TP_PROTO(struct xfs_inode *ip, struct xfs_inode *arg_ip), TP_ARGS(ip, arg_ip),