Commit 2fdbc200 authored by NeilBrown's avatar NeilBrown Committed by Trond Myklebust
Browse files

NFS: avoid infinite loop in pnfs_update_layout. 



If pnfsd_update_layout() is called on a file for which recovery has
failed it will enter a tight infinite loop.

NFS_LAYOUT_INVALID_STID will be set, nfs4_select_rw_stateid() will
return -EIO, and nfs4_schedule_stateid_recovery() will do nothing, so
nfs4_client_recover_expired_lease() will not wait.  So the code will
loop indefinitely.

Break the loop by testing the validity of the open stateid at the top of
the loop.

Signed-off-by: default avatarNeilBrown <neilb@suse.de>
Signed-off-by: default avatarTrond Myklebust <trond.myklebust@hammerspace.com>
parent 0b81371d

fs/nfs/pnfs.c

+8 −0
Original line number Diff line number Diff line
@@ -1999,6 +1999,14 @@ pnfs_update_layout(struct inode *ino, 
	}



lookup_again:

	if (!nfs4_valid_open_stateid(ctx->state)) {

		trace_pnfs_update_layout(ino, pos, count,

					 iomode, lo, lseg,

					 PNFS_UPDATE_LAYOUT_INVALID_OPEN);

		lseg = ERR_PTR(-EIO);

		goto out;

	}



	lseg = ERR_PTR(nfs4_client_recover_expired_lease(clp));

	if (IS_ERR(lseg))

		goto out;