From: Sagi Grimberg <sagi@grimberg.me>
Date: Tue, 21 May 2024 12:58:40 +0000 (+0300)
Subject: nfs: propagate readlink errors in nfs_symlink_filler
X-Git-Tag: v6.10-rc4~27^2~6
X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=134d0b3f2440cdddd12fc3444c9c0f62331ce6fc;p=linux-block.git

nfs: propagate readlink errors in nfs_symlink_filler

There is an inherent race where a symlink file may have been overriden
(by a different client) between lookup and readlink, resulting in a
spurious EIO error returned to userspace. Fix this by propagating back
ESTALE errors such that the vfs will retry the lookup/get_link (similar
to nfs4_file_open) at least once.

Cc: Dan Aloni <dan.aloni@vastdata.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
---

diff --git a/fs/nfs/symlink.c b/fs/nfs/symlink.c
index 0e27a2e4e68b..13818129d268 100644
--- a/fs/nfs/symlink.c
+++ b/fs/nfs/symlink.c
@@ -41,7 +41,7 @@ static int nfs_symlink_filler(struct file *file, struct folio *folio)
 error:
 	folio_set_error(folio);
 	folio_unlock(folio);
-	return -EIO;
+	return error;
 }
 
 static const char *nfs_get_link(struct dentry *dentry,