From 98021821a502db347bd9c7671beeee6e8ce07ea6 Mon Sep 17 00:00:00 2001 From: Dave Chinner Date: Mon, 12 Nov 2012 22:54:03 +1100 Subject: [PATCH] xfs: verify superblocks as they are read from disk Add a superblock verify callback function and pass it into the buffer read functions. Remove the now redundant verification code that is currently in use. Adding verification shows that secondary superblocks never have their "sb_inprogress" flag cleared by mkfs.xfs, so when validating the secondary superblocks during a grow operation we have to avoid checking this field. Even if we fix mkfs, we will still have to ignore this field for verification purposes unless a version of mkfs that does not have this bug was used. Signed-off-by: Dave Chinner Reviewed-by: Phil White Signed-off-by: Ben Myers --- fs/xfs/xfs_fsops.c | 4 +- fs/xfs/xfs_log_recover.c | 5 +- fs/xfs/xfs_mount.c | 98 +++++++++++++++++++++++++--------------- fs/xfs/xfs_mount.h | 3 +- 4 files changed, 69 insertions(+), 41 deletions(-) diff --git a/fs/xfs/xfs_fsops.c b/fs/xfs/xfs_fsops.c index f35f8d7731f0..cb65b067ed31 100644 --- a/fs/xfs/xfs_fsops.c +++ b/fs/xfs/xfs_fsops.c @@ -444,7 +444,8 @@ xfs_growfs_data_private( if (agno < oagcount) { error = xfs_trans_read_buf(mp, NULL, mp->m_ddev_targp, XFS_AGB_TO_DADDR(mp, agno, XFS_SB_BLOCK(mp)), - XFS_FSS_TO_BB(mp, 1), 0, &bp, NULL); + XFS_FSS_TO_BB(mp, 1), 0, &bp, + xfs_sb_read_verify); } else { bp = xfs_trans_get_buf(NULL, mp->m_ddev_targp, XFS_AGB_TO_DADDR(mp, agno, XFS_SB_BLOCK(mp)), @@ -462,6 +463,7 @@ xfs_growfs_data_private( break; } xfs_sb_to_disk(XFS_BUF_TO_SBP(bp), &mp->m_sb, XFS_SB_ALL_BITS); + /* * If we get an error writing out the alternate superblocks, * just issue a warning and continue. The real work is diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c index eb1e29ff0c7c..924a4bc3d49a 100644 --- a/fs/xfs/xfs_log_recover.c +++ b/fs/xfs/xfs_log_recover.c @@ -3692,13 +3692,14 @@ xlog_do_recover( /* * Now that we've finished replaying all buffer and inode - * updates, re-read in the superblock. + * updates, re-read in the superblock and reverify it. */ bp = xfs_getsb(log->l_mp, 0); XFS_BUF_UNDONE(bp); ASSERT(!(XFS_BUF_ISWRITE(bp))); XFS_BUF_READ(bp); XFS_BUF_UNASYNC(bp); + bp->b_iodone = xfs_sb_read_verify; xfsbdstrat(log->l_mp, bp); error = xfs_buf_iowait(bp); if (error) { @@ -3710,7 +3711,7 @@ xlog_do_recover( /* Convert superblock from on-disk format */ sbp = &log->l_mp->m_sb; - xfs_sb_from_disk(log->l_mp, XFS_BUF_TO_SBP(bp)); + xfs_sb_from_disk(sbp, XFS_BUF_TO_SBP(bp)); ASSERT(sbp->sb_magicnum == XFS_SB_MAGIC); ASSERT(xfs_sb_good_version(sbp)); xfs_buf_relse(bp); diff --git a/fs/xfs/xfs_mount.c b/fs/xfs/xfs_mount.c index df6d0b2aade1..bff18d73c610 100644 --- a/fs/xfs/xfs_mount.c +++ b/fs/xfs/xfs_mount.c @@ -304,9 +304,8 @@ STATIC int xfs_mount_validate_sb( xfs_mount_t *mp, xfs_sb_t *sbp, - int flags) + bool check_inprogress) { - int loud = !(flags & XFS_MFSI_QUIET); /* * If the log device and data device have the @@ -316,21 +315,18 @@ xfs_mount_validate_sb( * a volume filesystem in a non-volume manner. */ if (sbp->sb_magicnum != XFS_SB_MAGIC) { - if (loud) - xfs_warn(mp, "bad magic number"); + xfs_warn(mp, "bad magic number"); return XFS_ERROR(EWRONGFS); } if (!xfs_sb_good_version(sbp)) { - if (loud) - xfs_warn(mp, "bad version"); + xfs_warn(mp, "bad version"); return XFS_ERROR(EWRONGFS); } if (unlikely( sbp->sb_logstart == 0 && mp->m_logdev_targp == mp->m_ddev_targp)) { - if (loud) - xfs_warn(mp, + xfs_warn(mp, "filesystem is marked as having an external log; " "specify logdev on the mount command line."); return XFS_ERROR(EINVAL); @@ -338,8 +334,7 @@ xfs_mount_validate_sb( if (unlikely( sbp->sb_logstart != 0 && mp->m_logdev_targp != mp->m_ddev_targp)) { - if (loud) - xfs_warn(mp, + xfs_warn(mp, "filesystem is marked as having an internal log; " "do not specify logdev on the mount command line."); return XFS_ERROR(EINVAL); @@ -373,8 +368,7 @@ xfs_mount_validate_sb( sbp->sb_dblocks == 0 || sbp->sb_dblocks > XFS_MAX_DBLOCKS(sbp) || sbp->sb_dblocks < XFS_MIN_DBLOCKS(sbp))) { - if (loud) - XFS_CORRUPTION_ERROR("SB sanity check failed", + XFS_CORRUPTION_ERROR("SB sanity check failed", XFS_ERRLEVEL_LOW, mp, sbp); return XFS_ERROR(EFSCORRUPTED); } @@ -383,12 +377,10 @@ xfs_mount_validate_sb( * Until this is fixed only page-sized or smaller data blocks work. */ if (unlikely(sbp->sb_blocksize > PAGE_SIZE)) { - if (loud) { - xfs_warn(mp, + xfs_warn(mp, "File system with blocksize %d bytes. " "Only pagesize (%ld) or less will currently work.", sbp->sb_blocksize, PAGE_SIZE); - } return XFS_ERROR(ENOSYS); } @@ -402,23 +394,20 @@ xfs_mount_validate_sb( case 2048: break; default: - if (loud) - xfs_warn(mp, "inode size of %d bytes not supported", + xfs_warn(mp, "inode size of %d bytes not supported", sbp->sb_inodesize); return XFS_ERROR(ENOSYS); } if (xfs_sb_validate_fsb_count(sbp, sbp->sb_dblocks) || xfs_sb_validate_fsb_count(sbp, sbp->sb_rblocks)) { - if (loud) - xfs_warn(mp, + xfs_warn(mp, "file system too large to be mounted on this system."); return XFS_ERROR(EFBIG); } - if (unlikely(sbp->sb_inprogress)) { - if (loud) - xfs_warn(mp, "file system busy"); + if (check_inprogress && sbp->sb_inprogress) { + xfs_warn(mp, "Offline file system operation in progress!"); return XFS_ERROR(EFSCORRUPTED); } @@ -426,9 +415,7 @@ xfs_mount_validate_sb( * Version 1 directory format has never worked on Linux. */ if (unlikely(!xfs_sb_version_hasdirv2(sbp))) { - if (loud) - xfs_warn(mp, - "file system using version 1 directory format"); + xfs_warn(mp, "file system using version 1 directory format"); return XFS_ERROR(ENOSYS); } @@ -521,11 +508,9 @@ out_unwind: void xfs_sb_from_disk( - struct xfs_mount *mp, + struct xfs_sb *to, xfs_dsb_t *from) { - struct xfs_sb *to = &mp->m_sb; - to->sb_magicnum = be32_to_cpu(from->sb_magicnum); to->sb_blocksize = be32_to_cpu(from->sb_blocksize); to->sb_dblocks = be64_to_cpu(from->sb_dblocks); @@ -627,6 +612,50 @@ xfs_sb_to_disk( } } +void +xfs_sb_read_verify( + struct xfs_buf *bp) +{ + struct xfs_mount *mp = bp->b_target->bt_mount; + struct xfs_sb sb; + int error; + + xfs_sb_from_disk(&sb, XFS_BUF_TO_SBP(bp)); + + /* + * Only check the in progress field for the primary superblock as + * mkfs.xfs doesn't clear it from secondary superblocks. + */ + error = xfs_mount_validate_sb(mp, &sb, bp->b_bn == XFS_SB_DADDR); + if (error) + xfs_buf_ioerror(bp, error); + bp->b_iodone = NULL; + xfs_buf_ioend(bp, 0); +} + +/* + * We may be probed for a filesystem match, so we may not want to emit + * messages when the superblock buffer is not actually an XFS superblock. + * If we find an XFS superblock, the run a normal, noisy mount because we are + * really going to mount it and want to know about errors. + */ +void +xfs_sb_quiet_read_verify( + struct xfs_buf *bp) +{ + struct xfs_sb sb; + + xfs_sb_from_disk(&sb, XFS_BUF_TO_SBP(bp)); + + if (sb.sb_magicnum == XFS_SB_MAGIC) { + /* XFS filesystem, verify noisily! */ + xfs_sb_read_verify(bp); + return; + } + /* quietly fail */ + xfs_buf_ioerror(bp, EFSCORRUPTED); +} + /* * xfs_readsb * @@ -652,7 +681,9 @@ xfs_readsb(xfs_mount_t *mp, int flags) reread: bp = xfs_buf_read_uncached(mp->m_ddev_targp, XFS_SB_DADDR, - BTOBB(sector_size), 0, NULL); + BTOBB(sector_size), 0, + loud ? xfs_sb_read_verify + : xfs_sb_quiet_read_verify); if (!bp) { if (loud) xfs_warn(mp, "SB buffer read failed"); @@ -667,15 +698,8 @@ reread: /* * Initialize the mount structure from the superblock. - * But first do some basic consistency checking. */ - xfs_sb_from_disk(mp, XFS_BUF_TO_SBP(bp)); - error = xfs_mount_validate_sb(mp, &(mp->m_sb), flags); - if (error) { - if (loud) - xfs_warn(mp, "SB validate failed"); - goto release_buf; - } + xfs_sb_from_disk(&mp->m_sb, XFS_BUF_TO_SBP(bp)); /* * We must be able to do sector-sized and sector-aligned IO. diff --git a/fs/xfs/xfs_mount.h b/fs/xfs/xfs_mount.h index dc306a09f56f..de9089acc610 100644 --- a/fs/xfs/xfs_mount.h +++ b/fs/xfs/xfs_mount.h @@ -385,10 +385,11 @@ extern void xfs_set_low_space_thresholds(struct xfs_mount *); #endif /* __KERNEL__ */ +extern void xfs_sb_read_verify(struct xfs_buf *); extern void xfs_mod_sb(struct xfs_trans *, __int64_t); extern int xfs_initialize_perag(struct xfs_mount *, xfs_agnumber_t, xfs_agnumber_t *); -extern void xfs_sb_from_disk(struct xfs_mount *, struct xfs_dsb *); +extern void xfs_sb_from_disk(struct xfs_sb *, struct xfs_dsb *); extern void xfs_sb_to_disk(struct xfs_dsb *, struct xfs_sb *, __int64_t); #endif /* __XFS_MOUNT_H__ */ -- 2.20.1