From: Darrick J. Wong <darrick.wong@xxxxxxxxxx> There's a really bad bug in xfs_reflink_allocate_cow -- if bmapi_write can return a zero error code but no mappings. This happens if there's an extent size hint (which causes allocation requests to be rounded to extsz granularity internally), but there wasn't a big enough chunk of free space to start filling at the extsz granularity and fill even one block of the range that we actually requested. In any case, if we got no mappings we can't possibly do anything useful with the contents of imap, so we must bail out with ENOSPC here. Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx> --- fs/xfs/xfs_reflink.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c index c4f0aff..2702469 100644 --- a/fs/xfs/xfs_reflink.c +++ b/fs/xfs/xfs_reflink.c @@ -464,6 +464,13 @@ xfs_reflink_allocate_cow( error = xfs_trans_commit(tp); if (error) return error; + + /* + * Allocation succeeded but the requested range was not even partially + * satisfied? Bail out! + */ + if (nimaps == 0) + return -ENOSPC; convert: return xfs_reflink_convert_cow_extent(ip, imap, offset_fsb, count_fsb, &dfops); -- To unsubscribe from this list: send the line "unsubscribe linux-xfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
