[PATCH 21/24] ubifs: Use a random number for cookies

From: Richard Weinberger
Date: Thu Dec 01 2016 - 16:24:12 EST


Signed-off-by: Richard Weinberger <richard@xxxxxx>
---
fs/ubifs/journal.c | 3 +++
fs/ubifs/ubifs.h | 1 +
2 files changed, 4 insertions(+)

diff --git a/fs/ubifs/journal.c b/fs/ubifs/journal.c
index 0698cccc6223..88d33775f18b 100644
--- a/fs/ubifs/journal.c
+++ b/fs/ubifs/journal.c
@@ -589,6 +589,7 @@ int ubifs_jnl_update(struct ubifs_info *c, const struct inode *dir,
dent->nlen = cpu_to_le16(fname_len(nm));
memcpy(dent->name, fname_name(nm), fname_len(nm));
dent->name[fname_len(nm)] = '\0';
+ dent->cookie = prandom_u32();

zero_dent_node_unused(dent);
ubifs_prep_grp_node(c, dent, dlen, 0);
@@ -1124,6 +1125,7 @@ int ubifs_jnl_rename(struct ubifs_info *c, const struct inode *old_dir,
dent->nlen = cpu_to_le16(fname_len(new_nm));
memcpy(dent->name, fname_name(new_nm), fname_len(new_nm));
dent->name[fname_len(new_nm)] = '\0';
+ dent->cookie = prandom_u32();
zero_dent_node_unused(dent);
ubifs_prep_grp_node(c, dent, dlen1, 0);

@@ -1142,6 +1144,7 @@ int ubifs_jnl_rename(struct ubifs_info *c, const struct inode *old_dir,
dent2->nlen = cpu_to_le16(fname_len(old_nm));
memcpy(dent2->name, fname_name(old_nm), fname_len(old_nm));
dent2->name[fname_len(old_nm)] = '\0';
+ dent2->cookie = prandom_u32();
zero_dent_node_unused(dent2);
ubifs_prep_grp_node(c, dent2, dlen2, 0);

diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h
index ca33efcb4335..85c74ad98898 100644
--- a/fs/ubifs/ubifs.h
+++ b/fs/ubifs/ubifs.h
@@ -39,6 +39,7 @@
#include <linux/security.h>
#include <linux/xattr.h>
#include <linux/fscrypto.h>
+#include <linux/random.h>
#include "ubifs-media.h"

/* Version of this UBIFS implementation */
--
2.7.3