From 913e96bc292e1bb248854686c79d6545ef3ee720 Mon Sep 17 00:00:00 2001 From: Dave Chinner Date: Tue, 21 May 2013 18:02:02 +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 --- fs/xfs/xfs_attr_remote.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/fs/xfs/xfs_attr_remote.c b/fs/xfs/xfs_attr_remote.c index aad95b08e76b..bcdc07c4e8f4 100644 --- a/fs/xfs/xfs_attr_remote.c +++ b/fs/xfs/xfs_attr_remote.c @@ -52,9 +52,11 @@ 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 @@ -206,8 +208,9 @@ 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; @@ -227,8 +230,8 @@ 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)) { -- GitLab