From 3702ce6ed71cd60451ab278088863456dcb0dd99 Mon Sep 17 00:00:00 2001 From: Dave Chinner Date: Mon, 12 Nov 2012 22:54:05 +1100 Subject: [PATCH] xfs: verify AGI blocks as they are read from disk Add an AGI block verify callback function and pass it into the buffer read functions. Remove the now redundant verification code that is currently in use. Signed-off-by: Dave Chinner Reviewed-by: Christoph Hellwig Signed-off-by: Ben Myers --- fs/xfs/xfs_ialloc.c | 56 ++++++++++++++++++++++++++++----------------- 1 file changed, 35 insertions(+), 21 deletions(-) diff --git a/fs/xfs/xfs_ialloc.c b/fs/xfs/xfs_ialloc.c index 12e3dead439d..5bd255e5f7b8 100644 --- a/fs/xfs/xfs_ialloc.c +++ b/fs/xfs/xfs_ialloc.c @@ -1472,6 +1472,40 @@ xfs_check_agi_unlinked( #define xfs_check_agi_unlinked(agi) #endif +static void +xfs_agi_read_verify( + struct xfs_buf *bp) +{ + struct xfs_mount *mp = bp->b_target->bt_mount; + struct xfs_agi *agi = XFS_BUF_TO_AGI(bp); + int agi_ok; + + /* + * Validate the magic number of the agi block. + */ + agi_ok = agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC) && + XFS_AGI_GOOD_VERSION(be32_to_cpu(agi->agi_versionnum)); + + /* + * during growfs operations, the perag is not fully initialised, + * so we can't use it for any useful checking. growfs ensures we can't + * use it by using uncached buffers that don't have the perag attached + * so we can detect and avoid this problem. + */ + if (bp->b_pag) + agi_ok = agi_ok && be32_to_cpu(agi->agi_seqno) == + bp->b_pag->pag_agno; + + if (unlikely(XFS_TEST_ERROR(!agi_ok, mp, XFS_ERRTAG_IALLOC_READ_AGI, + XFS_RANDOM_IALLOC_READ_AGI))) { + XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, agi); + xfs_buf_ioerror(bp, EFSCORRUPTED); + } + xfs_check_agi_unlinked(agi); + bp->b_iodone = NULL; + xfs_buf_ioend(bp, 0); +} + /* * Read in the allocation group header (inode allocation section) */ @@ -1482,38 +1516,18 @@ xfs_read_agi( xfs_agnumber_t agno, /* allocation group number */ struct xfs_buf **bpp) /* allocation group hdr buf */ { - struct xfs_agi *agi; /* allocation group header */ - int agi_ok; /* agi is consistent */ int error; ASSERT(agno != NULLAGNUMBER); error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp, XFS_AG_DADDR(mp, agno, XFS_AGI_DADDR(mp)), - XFS_FSS_TO_BB(mp, 1), 0, bpp, NULL); + XFS_FSS_TO_BB(mp, 1), 0, bpp, xfs_agi_read_verify); if (error) return error; ASSERT(!xfs_buf_geterror(*bpp)); - agi = XFS_BUF_TO_AGI(*bpp); - - /* - * Validate the magic number of the agi block. - */ - agi_ok = agi->agi_magicnum == cpu_to_be32(XFS_AGI_MAGIC) && - XFS_AGI_GOOD_VERSION(be32_to_cpu(agi->agi_versionnum)) && - be32_to_cpu(agi->agi_seqno) == agno; - if (unlikely(XFS_TEST_ERROR(!agi_ok, mp, XFS_ERRTAG_IALLOC_READ_AGI, - XFS_RANDOM_IALLOC_READ_AGI))) { - XFS_CORRUPTION_ERROR("xfs_read_agi", XFS_ERRLEVEL_LOW, - mp, agi); - xfs_trans_brelse(tp, *bpp); - return XFS_ERROR(EFSCORRUPTED); - } - xfs_buf_set_ref(*bpp, XFS_AGI_REF); - - xfs_check_agi_unlinked(agi); return 0; } -- 2.20.1