From 72e78b514ce3beb53b5ecea8f56586ac70a3dd81 Mon Sep 17 00:00:00 2001 From: Dave Chinner Date: Fri, 7 Jun 2013 22:24:55 +1000 Subject: [PATCH] xfs: remote attribute read too short Reading a maximally size remote attribute fails when CRCs are enabled with this verification error: XFS (vdb): remote attribute header does not match required off/len/owner) There are two reasons for this, the first being that the length of the buffer being read is determined from the args->rmtblkcnt which doesn't take into account CRC headers. Hence the mapped length ends up being too short and so we need to calculate it directly from the value length. The second is that the byte count of valid data within a buffer is capped by the length of the data and so doesn't take into account that the buffer might be longer due to headers. Hence we need to calculate the data space in the buffer first before calculating the actual byte count of data. Signed-off-by: Dave Chinner Reviewed-by: Ben Myers Signed-off-by: Ben Myers --- libxfs/xfs_attr_remote.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/libxfs/xfs_attr_remote.c b/libxfs/xfs_attr_remote.c index 09a168b0b..b9b2b50e2 100644 --- a/libxfs/xfs_attr_remote.c +++ b/libxfs/xfs_attr_remote.c @@ -29,9 +29,11 @@ xfs_attr3_rmt_blocks( struct xfs_mount *mp, int attrlen) { - int buflen = XFS_ATTR3_RMT_BUF_SPACE(mp, - mp->m_sb.sb_blocksize); - return (attrlen + buflen - 1) / buflen; + if (xfs_sb_version_hascrc(&mp->m_sb)) { + int buflen = XFS_ATTR3_RMT_BUF_SPACE(mp, mp->m_sb.sb_blocksize); + return (attrlen + buflen - 1) / buflen; + } + return XFS_B_TO_FSB(mp, attrlen); } static bool @@ -183,8 +185,9 @@ xfs_attr_rmtval_get( while (valuelen > 0) { nmap = ATTR_RMTVALUE_MAPSIZE; + blkcnt = xfs_attr3_rmt_blocks(mp, valuelen); error = xfs_bmapi_read(args->dp, (xfs_fileoff_t)lblkno, - args->rmtblkcnt, map, &nmap, + blkcnt, map, &nmap, XFS_BMAPI_ATTRFORK); if (error) return error; @@ -204,8 +207,8 @@ xfs_attr_rmtval_get( if (error) return error; - byte_cnt = min_t(int, valuelen, BBTOB(bp->b_length)); - byte_cnt = XFS_ATTR3_RMT_BUF_SPACE(mp, byte_cnt); + byte_cnt = XFS_ATTR3_RMT_BUF_SPACE(mp, BBTOB(bp->b_length)); + byte_cnt = min_t(int, valuelen, byte_cnt); src = bp->b_addr; if (xfs_sb_version_hascrc(&mp->m_sb)) { -- 2.47.2