[PATCH AUTOSEL 5.15 03/11] NFSv4: Retry LOCK on OLD_STATEID during delegation return

From: Sasha Levin
Date: Thu Nov 10 2022 - 21:37:24 EST


From: Benjamin Coddington <bcodding@xxxxxxxxxx>

[ Upstream commit f5ea16137a3fa2858620dc9084466491c128535f ]

There's a small window where a LOCK sent during a delegation return can
race with another OPEN on client, but the open stateid has not yet been
updated. In this case, the client doesn't handle the OLD_STATEID error
from the server and will lose this lock, emitting:
"NFS: nfs4_handle_delegation_recall_error: unhandled error -10024".

Fix this by sending the task through the nfs4 error handling in
nfs4_lock_done() when we may have to reconcile our stateid with what the
server believes it to be. For this case, the result is a retry of the
LOCK operation with the updated stateid.

Reported-by: Gonzalo Siero Humet <gsierohu@xxxxxxxxxx>
Signed-off-by: Benjamin Coddington <bcodding@xxxxxxxxxx>
Signed-off-by: Anna Schumaker <Anna.Schumaker@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/nfs/nfs4proc.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index b42e332775fe..dc03924b6b71 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -7118,6 +7118,7 @@ static void nfs4_lock_done(struct rpc_task *task, void *calldata)
{
struct nfs4_lockdata *data = calldata;
struct nfs4_lock_state *lsp = data->lsp;
+ struct nfs_server *server = NFS_SERVER(d_inode(data->ctx->dentry));

dprintk("%s: begin!\n", __func__);

@@ -7127,8 +7128,7 @@ static void nfs4_lock_done(struct rpc_task *task, void *calldata)
data->rpc_status = task->tk_status;
switch (task->tk_status) {
case 0:
- renew_lease(NFS_SERVER(d_inode(data->ctx->dentry)),
- data->timestamp);
+ renew_lease(server, data->timestamp);
if (data->arg.new_lock && !data->cancelled) {
data->fl.fl_flags &= ~(FL_SLEEP | FL_ACCESS);
if (locks_lock_inode_wait(lsp->ls_state->inode, &data->fl) < 0)
@@ -7149,6 +7149,8 @@ static void nfs4_lock_done(struct rpc_task *task, void *calldata)
if (!nfs4_stateid_match(&data->arg.open_stateid,
&lsp->ls_state->open_stateid))
goto out_restart;
+ else if (nfs4_async_handle_error(task, server, lsp->ls_state, NULL) == -EAGAIN)
+ goto out_restart;
} else if (!nfs4_stateid_match(&data->arg.lock_stateid,
&lsp->ls_stateid))
goto out_restart;
--
2.35.1