linux-kernel - [PATCH 4.19 002/195] ovl: fix lseek overflow on 32bit

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: <20200210122305.999066195@linuxfoundation.org>
Date:   Mon, 10 Feb 2020 04:31:00 -0800
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Boris Gjenero <boris.gjenero@...il.com>,
        Miklos Szeredi <mszeredi@...hat.com>,
        Sasha Levin <sashal@...nel.org>
Subject: [PATCH 4.19 002/195] ovl: fix lseek overflow on 32bit

From: Miklos Szeredi <mszeredi@...hat.com>

[ Upstream commit a4ac9d45c0cd14a2adc872186431c79804b77dbf ]

ovl_lseek() is using ssize_t to return the value from vfs_llseek().  On a
32-bit kernel ssize_t is a 32-bit signed int, which overflows above 2 GB.

Assign the return value of vfs_llseek() to loff_t to fix this.

Reported-by: Boris Gjenero <boris.gjenero@...il.com>
Fixes: 9e46b840c705 ("ovl: support stacked SEEK_HOLE/SEEK_DATA")
Cc: <stable@...r.kernel.org> # v4.19
Signed-off-by: Miklos Szeredi <mszeredi@...hat.com>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 fs/overlayfs/file.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c
index 0bd276e4ccbee..fa5ac5de807c5 100644
--- a/fs/overlayfs/file.c
+++ b/fs/overlayfs/file.c
@@ -149,7 +149,7 @@ static loff_t ovl_llseek(struct file *file, loff_t offset, int whence)
 	struct inode *inode = file_inode(file);
 	struct fd real;
 	const struct cred *old_cred;
-	ssize_t ret;
+	loff_t ret;
 
 	/*
 	 * The two special cases below do not need to involve real fs,
-- 
2.20.1