diff --git a/stand/libsa/zfs/zfsimpl.c b/stand/libsa/zfs/zfsimpl.c index ceaeeb2e77f3..2240eb765c41 100644 --- a/stand/libsa/zfs/zfsimpl.c +++ b/stand/libsa/zfs/zfsimpl.c @@ -2349,6 +2349,19 @@ dnode_read(const spa_t *spa, const dnode_phys_t *dnode, off_t offset, return (EIO); } + /* + * Handle odd block sizes, mirrors dmu_read_impl(). Data can't exist + * past the first block, so we'll clip the read to the portion of the + * buffer within bsize and zero out the remainder. + */ + if (dnode->dn_maxblkid == 0) { + size_t newbuflen; + + newbuflen = offset > bsize ? 0 : MIN(buflen, bsize - offset); + bzero((char *)buf + newbuflen, buflen - newbuflen); + buflen = newbuflen; + } + /* * Note: bsize may not be a power of two here so we need to do an * actual divide rather than a bitshift.