From 3d3e6f64e22c94115d47de670611bcd3ecda3796 Mon Sep 17 00:00:00 2001 From: Dave Chinner Date: Mon, 12 Nov 2012 22:54:08 +1100 Subject: xfs: verify btree blocks as they are read from disk Add an btree block verify callback function and pass it into the buffer read functions. Because each different btree block type requires different verification, add a function to the ops structure that is called from the generic code. Also, propagate the verification callback functions through the readahead functions, and into the external bmap and bulkstat inode readahead code that uses the generic btree buffer read functions. Signed-off-by: Dave Chinner Reviewed-by: Phil White Signed-off-by: Ben Myers --- fs/xfs/xfs_alloc_btree.c | 61 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 61 insertions(+) (limited to 'fs/xfs/xfs_alloc_btree.c') diff --git a/fs/xfs/xfs_alloc_btree.c b/fs/xfs/xfs_alloc_btree.c index f7876c6d6165..46961e52e9b8 100644 --- a/fs/xfs/xfs_alloc_btree.c +++ b/fs/xfs/xfs_alloc_btree.c @@ -272,6 +272,66 @@ xfs_allocbt_key_diff( return (__int64_t)be32_to_cpu(kp->ar_startblock) - rec->ar_startblock; } +void +xfs_allocbt_read_verify( + struct xfs_buf *bp) +{ + struct xfs_mount *mp = bp->b_target->bt_mount; + struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp); + struct xfs_perag *pag = bp->b_pag; + unsigned int level; + int sblock_ok; /* block passes checks */ + + /* + * magic number and level verification + * + * During growfs operations, we can't verify the exact level as the + * perag is not fully initialised and hence not attached to the buffer. + * In this case, check against the maximum tree depth. + */ + level = be16_to_cpu(block->bb_level); + switch (block->bb_magic) { + case cpu_to_be32(XFS_ABTB_MAGIC): + if (pag) + sblock_ok = level < pag->pagf_levels[XFS_BTNUM_BNOi]; + else + sblock_ok = level < mp->m_ag_maxlevels; + break; + case cpu_to_be32(XFS_ABTC_MAGIC): + if (pag) + sblock_ok = level < pag->pagf_levels[XFS_BTNUM_CNTi]; + else + sblock_ok = level < mp->m_ag_maxlevels; + break; + default: + sblock_ok = 0; + break; + } + + /* numrecs verification */ + sblock_ok = sblock_ok && + be16_to_cpu(block->bb_numrecs) <= mp->m_alloc_mxr[level != 0]; + + /* sibling pointer verification */ + sblock_ok = sblock_ok && + (block->bb_u.s.bb_leftsib == cpu_to_be32(NULLAGBLOCK) || + be32_to_cpu(block->bb_u.s.bb_leftsib) < mp->m_sb.sb_agblocks) && + block->bb_u.s.bb_leftsib && + (block->bb_u.s.bb_rightsib == cpu_to_be32(NULLAGBLOCK) || + be32_to_cpu(block->bb_u.s.bb_rightsib) < mp->m_sb.sb_agblocks) && + block->bb_u.s.bb_rightsib; + + if (!sblock_ok) { + trace_xfs_btree_corrupt(bp, _RET_IP_); + XFS_CORRUPTION_ERROR("xfs_allocbt_read_verify", + XFS_ERRLEVEL_LOW, mp, block); + xfs_buf_ioerror(bp, EFSCORRUPTED); + } + + bp->b_iodone = NULL; + xfs_buf_ioend(bp, 0); +} + #ifdef DEBUG STATIC int xfs_allocbt_keys_inorder( @@ -327,6 +387,7 @@ static const struct xfs_btree_ops xfs_allocbt_ops = { .init_rec_from_cur = xfs_allocbt_init_rec_from_cur, .init_ptr_from_cur = xfs_allocbt_init_ptr_from_cur, .key_diff = xfs_allocbt_key_diff, + .read_verify = xfs_allocbt_read_verify, #ifdef DEBUG .keys_inorder = xfs_allocbt_keys_inorder, .recs_inorder = xfs_allocbt_recs_inorder, -- cgit