From: "Darrick J. Wong" If an inode has the incore verity iflag set, make sure that we can actually activate fsverity on that inode. If activation fails due to a fsverity metadata validation error, clear the flag. The usage model for fsverity requires that any program that cares about verity state is required to call statx/getflags to check that the flag is set after opening the file, so clearing the flag will not compromise that model. Signed-off-by: Darrick J. Wong Signed-off-by: Andrey Albershteyn --- fs/xfs/scrub/attr.c | 7 +++++ fs/xfs/scrub/common.c | 53 +++++++++++++++++++++++++++++++++++++ fs/xfs/scrub/common.h | 2 ++ fs/xfs/scrub/inode.c | 7 +++++ fs/xfs/scrub/inode_repair.c | 36 +++++++++++++++++++++++++ 5 files changed, 105 insertions(+) diff --git a/fs/xfs/scrub/attr.c b/fs/xfs/scrub/attr.c index 390ac2e11ee0..daf7962c2374 100644 --- a/fs/xfs/scrub/attr.c +++ b/fs/xfs/scrub/attr.c @@ -649,6 +649,13 @@ xchk_xattr( if (!xfs_inode_hasattr(sc->ip)) return -ENOENT; + /* + * 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/common.c b/fs/xfs/scrub/common.c index 20e63069088b..6cc6bea9c554 100644 --- a/fs/xfs/scrub/common.c +++ b/fs/xfs/scrub/common.c @@ -45,6 +45,8 @@ #include "scrub/health.h" #include "scrub/tempfile.h" +#include + /* Common code for the metadata scrubbers. */ /* @@ -1743,3 +1745,54 @@ xchk_inode_count_blocks( return xfs_bmap_count_blocks(sc->tp, sc->ip, whichfork, nextents, count); } + +/* + * If this inode has S_VERITY set on it, read the verity info. If the reading + * fails with anything other than ENOMEM, the file is corrupt, which we can + * detect later with fsverity_active. + * + * Callers must hold the IOLOCK and must not hold the ILOCK of sc->ip because + * activation reads inode data. + */ +int +xchk_inode_setup_verity( + struct xfs_scrub *sc) +{ + int error; + + if (!fsverity_active(VFS_I(sc->ip))) + return 0; + + error = fsverity_ensure_verity_info(VFS_I(sc->ip)); + switch (error) { + case 0: + /* fsverity is active */ + break; + case -ENODATA: + case -EMSGSIZE: + case -EINVAL: + case -EFSCORRUPTED: + case -EFBIG: + /* + * The nonzero errno codes above are the error codes that can + * be returned from fsverity on metadata validation errors. + */ + return 0; + default: + /* runtime errors */ + return error; + } + + return 0; +} + +/* + * Is this a verity file that failed to activate? Callers must have tried to + * activate fsverity via xchk_inode_setup_verity. + */ +bool +xchk_inode_verity_broken( + struct xfs_inode *ip) +{ + return fsverity_active(VFS_I(ip)) && !fsverity_get_info(VFS_I(ip)); +} diff --git a/fs/xfs/scrub/common.h b/fs/xfs/scrub/common.h index f2ecc68538f0..aa16d310bd6d 100644 --- a/fs/xfs/scrub/common.h +++ b/fs/xfs/scrub/common.h @@ -264,6 +264,8 @@ int xchk_inode_is_allocated(struct xfs_scrub *sc, xfs_agino_t agino, bool *inuse); int xchk_inode_count_blocks(struct xfs_scrub *sc, int whichfork, xfs_extnum_t *nextents, xfs_filblks_t *count); +int xchk_inode_setup_verity(struct xfs_scrub *sc); +bool xchk_inode_verity_broken(struct xfs_inode *ip); bool xchk_inode_is_dirtree_root(const struct xfs_inode *ip); bool xchk_inode_is_sb_rooted(const struct xfs_inode *ip); diff --git a/fs/xfs/scrub/inode.c b/fs/xfs/scrub/inode.c index 948d04dcba2a..8ce6917e22b4 100644 --- a/fs/xfs/scrub/inode.c +++ b/fs/xfs/scrub/inode.c @@ -36,6 +36,10 @@ xchk_prepare_iscrub( xchk_ilock(sc, XFS_IOLOCK_EXCL); + error = xchk_inode_setup_verity(sc); + if (error) + return error; + error = xchk_trans_alloc(sc, 0); if (error) return error; @@ -833,6 +837,9 @@ xchk_inode( if (S_ISREG(VFS_I(sc->ip)->i_mode)) xchk_inode_check_reflink_iflag(sc, sc->ip->i_ino); + if (xchk_inode_verity_broken(sc->ip)) + xchk_ino_set_corrupt(sc, sc->sm->sm_ino); + xchk_inode_check_unlinked(sc); xchk_inode_xref(sc, sc->ip->i_ino, &di); diff --git a/fs/xfs/scrub/inode_repair.c b/fs/xfs/scrub/inode_repair.c index 9738b9ce3f2d..3761e3922466 100644 --- a/fs/xfs/scrub/inode_repair.c +++ b/fs/xfs/scrub/inode_repair.c @@ -573,6 +573,8 @@ xrep_dinode_flags( dip->di_nrext64_pad = 0; else if (dip->di_version >= 3) dip->di_v3_pad = 0; + if (!xfs_has_verity(mp) || !S_ISREG(mode)) + flags2 &= ~XFS_DIFLAG2_VERITY; if (flags2 & XFS_DIFLAG2_METADATA) { xfs_failaddr_t fa; @@ -1613,6 +1615,10 @@ xrep_dinode_core( if (iget_error) return iget_error; + error = xchk_inode_setup_verity(sc); + if (error) + return error; + error = xchk_trans_alloc(sc, 0); if (error) return error; @@ -2032,6 +2038,27 @@ xrep_inode_unlinked( return 0; } +/* + * If this file is a fsverity file, xchk_prepare_iscrub or xrep_dinode_core + * should have activated it. If it's still not active, then there's something + * wrong with the verity descriptor and we should turn it off. + */ +STATIC int +xrep_inode_verity( + struct xfs_scrub *sc) +{ + struct inode *inode = VFS_I(sc->ip); + + if (xchk_inode_verity_broken(sc->ip)) { + sc->ip->i_diflags2 &= ~XFS_DIFLAG2_VERITY; + inode->i_flags &= ~S_VERITY; + + xfs_trans_log_inode(sc->tp, sc->ip, XFS_ILOG_CORE); + } + + return 0; +} + /* Repair an inode's fields. */ int xrep_inode( @@ -2081,6 +2108,15 @@ xrep_inode( return error; } + /* + * Disable fsverity if it cannot be activated. Activation failure + * prohibits the file from being opened, so there cannot be another + * program with an open fd to what it thinks is a verity file. + */ + error = xrep_inode_verity(sc); + if (error) + return error; + /* Reconnect incore unlinked list */ error = xrep_inode_unlinked(sc); if (error) -- 2.51.2