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From: Jorge Mora <jmora1300@gmail.com>
To: linux-nfs@vger.kernel.org
Cc: chuck.lever@oracle.com,
	jlayton@kernel.org
Subject: [PATCH] NFSD: fix LISTXATTRS returning more bytes than maxcount
Date: Thu, 25 Jan 2024 07:42:23 -0700
Message-ID: <20240125144223.12725-1-mora@netapp.com>
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The maxcount is the maximum number of bytes for the LISTXATTRS4resok
result. This includes the cookie and the count for the name array,
thus subtract 12 bytes from the maxcount: 8 (cookie) + 4 (array count)
when filling up the name array.

Fixes: 23e50fe3a5e6 ("nfsd: implement the xattr functions and en/decode logic")
Signed-off-by: Jorge Mora <mora@netapp.com>
---
 fs/nfsd/nfs4xdr.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index 92c7dde148a4..17e6404f4296 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -5168,7 +5168,8 @@ nfsd4_encode_listxattrs(struct nfsd4_compoundres *resp, __be32 nfserr,
 	sp = listxattrs->lsxa_buf;
 	nuser = 0;
 
-	xdrleft = listxattrs->lsxa_maxcount;
+	/* Bytes left is maxcount - 8 (cookie) - 4 (array count) */
+	xdrleft = listxattrs->lsxa_maxcount - 12;
 
 	while (left > 0 && xdrleft > 0) {
 		slen = strlen(sp);
-- 
2.43.0