linux-kernel - [PATCHv1 1/2] libfs: allow simple_fill

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]

Date:	Tue, 17 May 2016 11:27:22 +0100
From:	David Vrabel <david.vrabel@...rix.com>
To:	Alexander Viro <viro@...iv.linux.org.uk>
CC:	David Vrabel <david.vrabel@...rix.com>,
	<linux-fsdevel@...r.kernel.org>, <linux-kernel@...r.kernel.org>,
	<xen-devel@...ts.xenproject.org>,
	"Boris Ostrovsky" <boris.ostrovsky@...cle.com>,
	Juergen Gross <jgross@...e.com>
Subject: [PATCHv1 1/2] libfs: allow simple_fill_super() to add symlinks

simple_fill_super() will add symlinks if an entry has mode & S_IFLNK.
The target is provided in the new "link" field.

Signed-off-by: David Vrabel <david.vrabel@...rix.com>
---
v2:
- simplified.
---
 fs/libfs.c         | 15 +++++++++++++--
 include/linux/fs.h |  2 +-
 2 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/fs/libfs.c b/fs/libfs.c
index f3fa82c..5b3a391 100644
--- a/fs/libfs.c
+++ b/fs/libfs.c
@@ -517,9 +517,20 @@ int simple_fill_super(struct super_block *s, unsigned long magic,
 			dput(dentry);
 			goto out;
 		}
-		inode->i_mode = S_IFREG | files->mode;
+		if (files->mode & S_IFLNK) {
+			inode->i_mode = files->mode;
+			inode->i_op = &simple_symlink_inode_operations;
+			inode->i_link = kstrdup(files->link, GFP_KERNEL);
+			if (!inode->i_link) {
+				iput(inode);
+				dput(dentry);
+				goto out;
+			}
+		} else {
+			inode->i_mode = S_IFREG | files->mode;
+			inode->i_fop = files->ops;
+		}
 		inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
-		inode->i_fop = files->ops;
 		inode->i_ino = i;
 		d_add(dentry, inode);
 	}
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 70e61b5..8a09998 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2897,7 +2897,7 @@ extern const struct file_operations simple_dir_operations;
 extern const struct inode_operations simple_dir_inode_operations;
 extern void make_empty_dir_inode(struct inode *inode);
 extern bool is_empty_dir_inode(struct inode *inode);
-struct tree_descr { char *name; const struct file_operations *ops; int mode; };
+struct tree_descr { char *name; const struct file_operations *ops; int mode; char *link; };
 struct dentry *d_alloc_name(struct dentry *, const char *);
 extern int simple_fill_super(struct super_block *, unsigned long, struct tree_descr *);
 extern int simple_pin_fs(struct file_system_type *, struct vfsmount **mount, int *count);
-- 
2.1.4