From 3fe58f30b4fc3f8a9084b035a02bc0c67bee8d00 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 3 Apr 2013 16:11:16 +1100 Subject: [PATCH] xfs: add CRC checks for quota blocks Use the reserved space in struct xfs_dqblk to store a UUID and a crc for the quota blocks. [dchinner@redhat.com] Add a LSN field and update for current verifier infrastructure. Signed-off-by: Christoph Hellwig Signed-off-by: Dave Chinner Reviewed-by: Ben Myers Signed-off-by: Ben Myers --- fs/xfs/xfs_dquot.c | 112 ++++++++++++++++++++++++++++++++++----- fs/xfs/xfs_log_recover.c | 10 ++++ fs/xfs/xfs_qm.c | 23 ++++++-- fs/xfs/xfs_qm.h | 2 + fs/xfs/xfs_quota.h | 11 +++- 5 files changed, 141 insertions(+), 17 deletions(-) diff --git a/fs/xfs/xfs_dquot.c b/fs/xfs/xfs_dquot.c index 45bb08f6ba17..a41f8bf1da37 100644 --- a/fs/xfs/xfs_dquot.c +++ b/fs/xfs/xfs_dquot.c @@ -36,6 +36,7 @@ #include "xfs_trans_space.h" #include "xfs_trans_priv.h" #include "xfs_qm.h" +#include "xfs_cksum.h" #include "xfs_trace.h" /* @@ -248,6 +249,8 @@ xfs_qm_init_dquot_blk( d->dd_diskdq.d_version = XFS_DQUOT_VERSION; d->dd_diskdq.d_id = cpu_to_be32(curid); d->dd_diskdq.d_flags = type; + if (xfs_sb_version_hascrc(&mp->m_sb)) + uuid_copy(&d->dd_uuid, &mp->m_sb.sb_uuid); } xfs_trans_dquot_buf(tp, bp, @@ -283,16 +286,77 @@ xfs_dquot_set_prealloc_limits(struct xfs_dquot *dqp) dqp->q_low_space[XFS_QLOWSP_5_PCNT] = space * 5; } -static void +STATIC void +xfs_dquot_buf_calc_crc( + struct xfs_mount *mp, + struct xfs_buf *bp) +{ + struct xfs_dqblk *d = (struct xfs_dqblk *)bp->b_addr; + int i; + + if (!xfs_sb_version_hascrc(&mp->m_sb)) + return; + + for (i = 0; i < mp->m_quotainfo->qi_dqperchunk; i++, d++) { + xfs_update_cksum((char *)d, sizeof(struct xfs_dqblk), + offsetof(struct xfs_dqblk, dd_crc)); + } +} + +STATIC bool +xfs_dquot_buf_verify_crc( + struct xfs_mount *mp, + struct xfs_buf *bp) +{ + struct xfs_dqblk *d = (struct xfs_dqblk *)bp->b_addr; + int ndquots; + int i; + + if (!xfs_sb_version_hascrc(&mp->m_sb)) + return true; + + /* + * if we are in log recovery, the quota subsystem has not been + * initialised so we have no quotainfo structure. In that case, we need + * to manually calculate the number of dquots in the buffer. + */ + if (mp->m_quotainfo) + ndquots = mp->m_quotainfo->qi_dqperchunk; + else + ndquots = xfs_qm_calc_dquots_per_chunk(mp, + XFS_BB_TO_FSB(mp, bp->b_length)); + + for (i = 0; i < ndquots; i++, d++) { + if (!xfs_verify_cksum((char *)d, sizeof(struct xfs_dqblk), + offsetof(struct xfs_dqblk, dd_crc))) + return false; + if (!uuid_equal(&d->dd_uuid, &mp->m_sb.sb_uuid)) + return false; + } + + return true; +} + +STATIC bool xfs_dquot_buf_verify( + struct xfs_mount *mp, struct xfs_buf *bp) { - struct xfs_mount *mp = bp->b_target->bt_mount; struct xfs_dqblk *d = (struct xfs_dqblk *)bp->b_addr; - struct xfs_disk_dquot *ddq; xfs_dqid_t id = 0; + int ndquots; int i; + /* + * if we are in log recovery, the quota subsystem has not been + * initialised so we have no quotainfo structure. In that case, we need + * to manually calculate the number of dquots in the buffer. + */ + if (mp->m_quotainfo) + ndquots = mp->m_quotainfo->qi_dqperchunk; + else + ndquots = xfs_qm_calc_dquots_per_chunk(mp, bp->b_length); + /* * On the first read of the buffer, verify that each dquot is valid. * We don't know what the id of the dquot is supposed to be, just that @@ -300,8 +364,9 @@ xfs_dquot_buf_verify( * first id is corrupt, then it will fail on the second dquot in the * buffer so corruptions could point to the wrong dquot in this case. */ - for (i = 0; i < mp->m_quotainfo->qi_dqperchunk; i++) { - int error; + for (i = 0; i < ndquots; i++) { + struct xfs_disk_dquot *ddq; + int error; ddq = &d[i].dd_diskdq; @@ -309,27 +374,37 @@ xfs_dquot_buf_verify( id = be32_to_cpu(ddq->d_id); error = xfs_qm_dqcheck(mp, ddq, id + i, 0, XFS_QMOPT_DOWARN, - "xfs_dquot_read_verify"); - if (error) { - XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, d); - xfs_buf_ioerror(bp, EFSCORRUPTED); - break; - } + "xfs_dquot_buf_verify"); + if (error) + return false; } + return true; } static void xfs_dquot_buf_read_verify( struct xfs_buf *bp) { - xfs_dquot_buf_verify(bp); + struct xfs_mount *mp = bp->b_target->bt_mount; + + if (!xfs_dquot_buf_verify_crc(mp, bp) || !xfs_dquot_buf_verify(mp, bp)) { + XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr); + xfs_buf_ioerror(bp, EFSCORRUPTED); + } } void xfs_dquot_buf_write_verify( struct xfs_buf *bp) { - xfs_dquot_buf_verify(bp); + struct xfs_mount *mp = bp->b_target->bt_mount; + + if (!xfs_dquot_buf_verify(mp, bp)) { + XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr); + xfs_buf_ioerror(bp, EFSCORRUPTED); + return; + } + xfs_dquot_buf_calc_crc(mp, bp); } const struct xfs_buf_ops xfs_dquot_buf_ops = { @@ -1072,6 +1147,17 @@ xfs_qm_dqflush( xfs_trans_ail_copy_lsn(mp->m_ail, &dqp->q_logitem.qli_flush_lsn, &dqp->q_logitem.qli_item.li_lsn); + /* + * copy the lsn into the on-disk dquot now while we have the in memory + * dquot here. This can't be done later in the write verifier as we + * can't get access to the log item at that point in time. + */ + if (xfs_sb_version_hascrc(&mp->m_sb)) { + struct xfs_dqblk *dqb = (struct xfs_dqblk *)ddqp; + + dqb->dd_lsn = cpu_to_be64(dqp->q_logitem.qli_item.li_lsn); + } + /* * Attach an iodone routine so that we can remove this dquot from the * AIL and release the flush lock once the dquot is synced to disk. diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c index 6778a7943db4..27b3ec214a67 100644 --- a/fs/xfs/xfs_log_recover.c +++ b/fs/xfs/xfs_log_recover.c @@ -1979,6 +1979,16 @@ xlog_recover_do_reg_buffer( } bp->b_ops = &xfs_agi_buf_ops; break; + case XFS_BLF_UDQUOT_BUF: + case XFS_BLF_PDQUOT_BUF: + case XFS_BLF_GDQUOT_BUF: + if (*(__be16 *)bp->b_addr != cpu_to_be16(XFS_DQUOT_MAGIC)) { + xfs_warn(mp, "Bad DQUOT block magic!"); + ASSERT(0); + break; + } + bp->b_ops = &xfs_dquot_buf_ops; + break; default: break; } diff --git a/fs/xfs/xfs_qm.c b/fs/xfs/xfs_qm.c index d0acb4e40a6f..f41702b43003 100644 --- a/fs/xfs/xfs_qm.c +++ b/fs/xfs/xfs_qm.c @@ -617,6 +617,20 @@ xfs_qm_dqdetach( } } +int +xfs_qm_calc_dquots_per_chunk( + struct xfs_mount *mp, + unsigned int nbblks) /* basic block units */ +{ + unsigned int ndquots; + + ASSERT(nbblks > 0); + ndquots = BBTOB(nbblks); + do_div(ndquots, sizeof(xfs_dqblk_t)); + + return ndquots; +} + /* * This initializes all the quota information that's kept in the * mount structure @@ -656,9 +670,8 @@ xfs_qm_init_quotainfo( /* Precalc some constants */ qinf->qi_dqchunklen = XFS_FSB_TO_BB(mp, XFS_DQUOT_CLUSTER_SIZE_FSB); - ASSERT(qinf->qi_dqchunklen); - qinf->qi_dqperchunk = BBTOB(qinf->qi_dqchunklen); - do_div(qinf->qi_dqperchunk, sizeof(xfs_dqblk_t)); + qinf->qi_dqperchunk = xfs_qm_calc_dquots_per_chunk(mp, + qinf->qi_dqchunklen); mp->m_qflags |= (mp->m_sb.sb_qflags & XFS_ALL_QUOTA_CHKD); @@ -897,6 +910,10 @@ xfs_qm_dqiter_bufs( if (error) break; + /* + * XXX(hch): need to figure out if it makes sense to validate + * the CRC here. + */ xfs_qm_reset_dqcounts(mp, bp, firstid, type); xfs_buf_delwri_queue(bp, buffer_list); xfs_buf_relse(bp); diff --git a/fs/xfs/xfs_qm.h b/fs/xfs/xfs_qm.h index 82c21084587b..5d16a6e6900f 100644 --- a/fs/xfs/xfs_qm.h +++ b/fs/xfs/xfs_qm.h @@ -75,6 +75,8 @@ typedef struct xfs_quotainfo { &((qi)->qi_gquota_tree)) +extern int xfs_qm_calc_dquots_per_chunk(struct xfs_mount *mp, + unsigned int nbblks); extern void xfs_trans_mod_dquot(xfs_trans_t *, xfs_dquot_t *, uint, long); extern int xfs_trans_reserve_quota_bydquots(xfs_trans_t *, xfs_mount_t *, xfs_dquot_t *, xfs_dquot_t *, long, long, uint); diff --git a/fs/xfs/xfs_quota.h b/fs/xfs/xfs_quota.h index b50ec5b95d5a..c61e31c7d997 100644 --- a/fs/xfs/xfs_quota.h +++ b/fs/xfs/xfs_quota.h @@ -77,7 +77,14 @@ typedef struct xfs_disk_dquot { */ typedef struct xfs_dqblk { xfs_disk_dquot_t dd_diskdq; /* portion that lives incore as well */ - char dd_fill[32]; /* filling for posterity */ + char dd_fill[4]; /* filling for posterity */ + + /* + * These two are only present on filesystems with the CRC bits set. + */ + __be32 dd_crc; /* checksum */ + __be64 dd_lsn; /* last modification in log */ + uuid_t dd_uuid; /* location information */ } xfs_dqblk_t; /* @@ -380,5 +387,7 @@ extern int xfs_qm_dqcheck(struct xfs_mount *, xfs_disk_dquot_t *, xfs_dqid_t, uint, uint, char *); extern int xfs_mount_reset_sbqflags(struct xfs_mount *); +extern const struct xfs_buf_ops xfs_dquot_buf_ops; + #endif /* __KERNEL__ */ #endif /* __XFS_QUOTA_H__ */ -- 2.20.1