From 6dcb1b1322f3277dc213309d9f4bf6d6c265115a Mon Sep 17 00:00:00 2001
From: Chuck Lever <chuck.lever@oracle.com>
Date: Thu, 17 Oct 2024 11:03:56 -0400
Subject: [PATCH] NFSD: Cap the number of bytes copied by
 nfs4_reset_recoverydir()

[ Upstream commit f64ea4af43161bb86ffc77e6aeb5bcf5c3229df0 ]

It's only current caller already length-checks the string, but let's
be safe.

Fixes: 0964a3d3f1aa ("[PATCH] knfsd: nfsd4 reboot dirname fix")
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/nfsd/nfs4recover.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/nfsd/nfs4recover.c b/fs/nfsd/nfs4recover.c
index 4395577825a7fa..892fecce18b802 100644
--- a/fs/nfsd/nfs4recover.c
+++ b/fs/nfsd/nfs4recover.c
@@ -658,7 +658,8 @@ nfs4_reset_recoverydir(char *recdir)
 		return status;
 	status = -ENOTDIR;
 	if (d_is_dir(path.dentry)) {
-		strcpy(user_recovery_dirname, recdir);
+		strscpy(user_recovery_dirname, recdir,
+			sizeof(user_recovery_dirname));
 		status = 0;
 	}
 	path_put(&path);