linux-kernel - [PATCH 5.4 062/141] NFSv4.2 fix handling of sr

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20210517140244.853295972@linuxfoundation.org>
Date:   Mon, 17 May 2021 16:01:54 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Olga Kornievskaia <kolga@...app.com>,
        Trond Myklebust <trond.myklebust@...merspace.com>,
        Sasha Levin <sashal@...nel.org>
Subject: [PATCH 5.4 062/141] NFSv4.2 fix handling of sr_eof in SEEKs reply

From: Olga Kornievskaia <kolga@...app.com>

[ Upstream commit 73f5c88f521a630ea1628beb9c2d48a2e777a419 ]

Currently the client ignores the value of the sr_eof of the SEEK
operation. According to the spec, if the server didn't find the
requested extent and reached the end of the file, the server
would return sr_eof=true. In case the request for DATA and no
data was found (ie in the middle of the hole), then the lseek
expects that ENXIO would be returned.

Fixes: 1c6dcbe5ceff8 ("NFS: Implement SEEK")
Signed-off-by: Olga Kornievskaia <kolga@...app.com>
Signed-off-by: Trond Myklebust <trond.myklebust@...merspace.com>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 fs/nfs/nfs42proc.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/fs/nfs/nfs42proc.c b/fs/nfs/nfs42proc.c
index 5c84e5b8c0d6..6b7c926824ae 100644
--- a/fs/nfs/nfs42proc.c
+++ b/fs/nfs/nfs42proc.c
@@ -500,7 +500,10 @@ static loff_t _nfs42_proc_llseek(struct file *filep,
 	if (status)
 		return status;
 
-	return vfs_setpos(filep, res.sr_offset, inode->i_sb->s_maxbytes);
+	if (whence == SEEK_DATA && res.sr_eof)
+		return -NFS4ERR_NXIO;
+	else
+		return vfs_setpos(filep, res.sr_offset, inode->i_sb->s_maxbytes);
 }
 
 loff_t nfs42_proc_llseek(struct file *filep, loff_t offset, int whence)
-- 
2.30.2