From dbc77f31e58b2902a5e7643761c04bf69f57a32a Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Mon, 1 Jul 2019 08:25:36 -0700 Subject: [PATCH] vfs: only allow FSSETXATTR to set DAX flag on files and dirs The DAX flag only applies to files and directories, so don't let it get set for other types of files. Signed-off-by: Darrick J. Wong Reviewed-by: Jan Kara --- fs/inode.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/fs/inode.c b/fs/inode.c index 0cbce5a0a23c..446d05e25f39 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -2239,6 +2239,14 @@ int vfs_ioc_fssetxattr_check(struct inode *inode, const struct fsxattr *old_fa, !S_ISREG(inode->i_mode) && !S_ISDIR(inode->i_mode)) return -EINVAL; + /* + * It is only valid to set the DAX flag on regular files and + * directories on filesystems. + */ + if ((fa->fsx_xflags & FS_XFLAG_DAX) && + !(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode))) + return -EINVAL; + /* Extent size hints of zero turn off the flags. */ if (fa->fsx_extsize == 0) fa->fsx_xflags &= ~(FS_XFLAG_EXTSIZE | FS_XFLAG_EXTSZINHERIT);