From: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx> commit 8b04013737341442ed914b336cde866b902664ae upstream. If the mirror count changes in the new layout we pick up inside ff_layout_pg_init_write(), then we can end up adding the request to the wrong mirror and corrupting the mirror->pg_list. Fixes: d600ad1f2bdb ("NFS41: pop some layoutget errors to application") Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx> Signed-off-by: Anna Schumaker <Anna.Schumaker@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/nfs/flexfilelayout/flexfilelayout.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/fs/nfs/flexfilelayout/flexfilelayout.c b/fs/nfs/flexfilelayout/flexfilelayout.c index 4539008502ce6..83149cbae0931 100644 --- a/fs/nfs/flexfilelayout/flexfilelayout.c +++ b/fs/nfs/flexfilelayout/flexfilelayout.c @@ -939,9 +939,8 @@ ff_layout_pg_init_write(struct nfs_pageio_descriptor *pgio, goto out_mds; /* Use a direct mapping of ds_idx to pgio mirror_idx */ - if (WARN_ON_ONCE(pgio->pg_mirror_count != - FF_LAYOUT_MIRROR_COUNT(pgio->pg_lseg))) - goto out_mds; + if (pgio->pg_mirror_count != FF_LAYOUT_MIRROR_COUNT(pgio->pg_lseg)) + goto out_eagain; for (i = 0; i < pgio->pg_mirror_count; i++) { ds = nfs4_ff_layout_prepare_ds(pgio->pg_lseg, i, true); @@ -960,11 +959,15 @@ ff_layout_pg_init_write(struct nfs_pageio_descriptor *pgio, } return; - +out_eagain: + pnfs_generic_pg_cleanup(pgio); + pgio->pg_error = -EAGAIN; + return; out_mds: pnfs_put_lseg(pgio->pg_lseg); pgio->pg_lseg = NULL; nfs_pageio_reset_write_mds(pgio); + pgio->pg_error = -EAGAIN; } static unsigned int -- 2.25.1