linux-ext4 - [PATCH 4/5] overlayfs: Check for range bounds before calling i

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: <39b4bf94f6723831a9798237bb1b4ae14da04d98.1587555962.git.riteshh@linux.ibm.com>
Date:   Thu, 23 Apr 2020 16:17:56 +0530
From:   Ritesh Harjani <riteshh@...ux.ibm.com>
To:     linux-ext4@...r.kernel.org
Cc:     jack@...e.cz, tytso@....edu, adilger@...ger.ca,
        darrick.wong@...cle.com, hch@...radead.org,
        Alexander Viro <viro@...iv.linux.org.uk>,
        Dan Carpenter <dan.carpenter@...cle.com>,
        "Aneesh Kumar K . V" <aneesh.kumar@...ux.ibm.com>,
        Ritesh Harjani <riteshh@...ux.ibm.com>,
        Murphy Zhou <jencce.kernel@...il.com>,
        Miklos Szeredi <miklos@...redi.hu>,
        Amir Goldstein <amir73il@...il.com>,
        linux-fsdevel@...r.kernel.org, linux-unionfs@...r.kernel.org
Subject: [PATCH 4/5] overlayfs: Check for range bounds before calling i_op->fiemap()

Underlying fs may not be able to handle the length in fiemap
beyond sb->s_maxbytes. So similar to how VFS ioctl does it,
add fiemap_check_ranges() check in ovl_fiemap() as well
before calling underlying fs i_op->fiemap() call.

Signed-off-by: Ritesh Harjani <riteshh@...ux.ibm.com>
---
 fs/overlayfs/inode.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c
index 79e8994e3bc1..9bcd2e96faad 100644
--- a/fs/overlayfs/inode.c
+++ b/fs/overlayfs/inode.c
@@ -455,16 +455,21 @@ static int ovl_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
 	int err;
 	struct inode *realinode = ovl_inode_real(inode);
 	const struct cred *old_cred;
+	u64 length;
 
 	if (!realinode->i_op->fiemap)
 		return -EOPNOTSUPP;
 
+	err = fiemap_check_ranges(realinode->i_sb, start, len, &length);
+	if (err)
+		return err;
+
 	old_cred = ovl_override_creds(inode->i_sb);
 
 	if (fieinfo->fi_flags & FIEMAP_FLAG_SYNC)
 		filemap_write_and_wait(realinode->i_mapping);
 
-	err = realinode->i_op->fiemap(realinode, fieinfo, start, len);
+	err = realinode->i_op->fiemap(realinode, fieinfo, start, length);
 	revert_creds(old_cred);
 
 	return err;
-- 
2.21.0