linux-ext4 - [PATCH v2] vfs: only allow SETFLAGS to set DAX flag on files and dirs

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-next>] [day] [month] [year] [list]

Message-Id: <20210719023834.104053-1-jefflexu@linux.alibaba.com>
Date:   Mon, 19 Jul 2021 10:38:34 +0800
From:   Jeffle Xu <jefflexu@...ux.alibaba.com>
To:     viro@...iv.linux.org.uk
Cc:     linux-fsdevel@...r.kernel.org, linux-ext4@...r.kernel.org,
        djwong@...nel.org
Subject: [PATCH v2] vfs: only allow SETFLAGS to set DAX flag on files and dirs

This is similar to commit dbc77f31e58b ("vfs: only allow FSSETXATTR to
set DAX flag on files and dirs").

Though the underlying filesystems may have filtered invalid flags, e.g.,
ext4_mask_flags() called in ext4_fileattr_set(), also check it in VFS
layer.

Signed-off-by: Jeffle Xu <jefflexu@...ux.alibaba.com>
---
changes since v1:
- add separate parentheses surrounding flag tests
---
 fs/ioctl.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/ioctl.c b/fs/ioctl.c
index 1e2204fa9963..90cfaa4db03a 100644
--- a/fs/ioctl.c
+++ b/fs/ioctl.c
@@ -835,7 +835,7 @@ static int fileattr_set_prepare(struct inode *inode,
 	 * It is only valid to set the DAX flag on regular files and
 	 * directories on filesystems.
 	 */
-	if ((fa->fsx_xflags & FS_XFLAG_DAX) &&
+	if (((fa->fsx_xflags & FS_XFLAG_DAX) || (fa->flags & FS_DAX_FL)) &&
 	    !(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode)))
 		return -EINVAL;
 
-- 
2.27.0