lkml.org 
[lkml]   [2019]   [Dec]   [3]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v2] fs: introduce is_dot_dotdot helper for cleanup
Date
There exists many similar and duplicate codes to check "." and "..",
so introduce is_dot_dotdot helper to make the code more clean.

Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
---

v2:
- use the better performance implementation of is_dot_dotdot
- make it static inline and move it to include/linux/fs.h

fs/crypto/fname.c | 15 ++-------------
fs/ecryptfs/crypto.c | 13 ++-----------
fs/f2fs/f2fs.h | 11 -----------
fs/namei.c | 6 ++----
include/linux/fs.h | 10 ++++++++++
5 files changed, 16 insertions(+), 39 deletions(-)

diff --git a/fs/crypto/fname.c b/fs/crypto/fname.c
index 3da3707..36be864 100644
--- a/fs/crypto/fname.c
+++ b/fs/crypto/fname.c
@@ -15,17 +15,6 @@
#include <crypto/skcipher.h>
#include "fscrypt_private.h"

-static inline bool fscrypt_is_dot_dotdot(const struct qstr *str)
-{
- if (str->len == 1 && str->name[0] == '.')
- return true;
-
- if (str->len == 2 && str->name[0] == '.' && str->name[1] == '.')
- return true;
-
- return false;
-}
-
/**
* fname_encrypt() - encrypt a filename
*
@@ -255,7 +244,7 @@ int fscrypt_fname_disk_to_usr(struct inode *inode,
const struct qstr qname = FSTR_TO_QSTR(iname);
struct fscrypt_digested_name digested_name;

- if (fscrypt_is_dot_dotdot(&qname)) {
+ if (is_dot_dotdot(&qname)) {
oname->name[0] = '.';
oname->name[iname->len - 1] = '.';
oname->len = iname->len;
@@ -323,7 +312,7 @@ int fscrypt_setup_filename(struct inode *dir, const struct qstr *iname,
memset(fname, 0, sizeof(struct fscrypt_name));
fname->usr_fname = iname;

- if (!IS_ENCRYPTED(dir) || fscrypt_is_dot_dotdot(iname)) {
+ if (!IS_ENCRYPTED(dir) || is_dot_dotdot(iname)) {
fname->disk_name.name = (unsigned char *)iname->name;
fname->disk_name.len = iname->len;
return 0;
diff --git a/fs/ecryptfs/crypto.c b/fs/ecryptfs/crypto.c
index f91db24..6f4db74 100644
--- a/fs/ecryptfs/crypto.c
+++ b/fs/ecryptfs/crypto.c
@@ -1991,16 +1991,6 @@ int ecryptfs_encrypt_and_encode_filename(
return rc;
}

-static bool is_dot_dotdot(const char *name, size_t name_size)
-{
- if (name_size == 1 && name[0] == '.')
- return true;
- else if (name_size == 2 && name[0] == '.' && name[1] == '.')
- return true;
-
- return false;
-}
-
/**
* ecryptfs_decode_and_decrypt_filename - converts the encoded cipher text name to decoded plaintext
* @plaintext_name: The plaintext name
@@ -2020,6 +2010,7 @@ int ecryptfs_decode_and_decrypt_filename(char **plaintext_name,
{
struct ecryptfs_mount_crypt_stat *mount_crypt_stat =
&ecryptfs_superblock_to_private(sb)->mount_crypt_stat;
+ const struct qstr file_name = {.name = name, .len = name_size};
char *decoded_name;
size_t decoded_name_size;
size_t packet_size;
@@ -2027,7 +2018,7 @@ int ecryptfs_decode_and_decrypt_filename(char **plaintext_name,

if ((mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES) &&
!(mount_crypt_stat->flags & ECRYPTFS_ENCRYPTED_VIEW_ENABLED)) {
- if (is_dot_dotdot(name, name_size)) {
+ if (is_dot_dotdot(&file_name)) {
rc = ecryptfs_copy_filename(plaintext_name,
plaintext_name_size,
name, name_size);
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 5a888a0..3d5e684 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -2767,17 +2767,6 @@ static inline bool f2fs_cp_error(struct f2fs_sb_info *sbi)
return is_set_ckpt_flags(sbi, CP_ERROR_FLAG);
}

-static inline bool is_dot_dotdot(const struct qstr *str)
-{
- if (str->len == 1 && str->name[0] == '.')
- return true;
-
- if (str->len == 2 && str->name[0] == '.' && str->name[1] == '.')
- return true;
-
- return false;
-}
-
static inline bool f2fs_may_extent_tree(struct inode *inode)
{
struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
diff --git a/fs/namei.c b/fs/namei.c
index 2dda552..babe7e8 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -2458,10 +2458,8 @@ static int lookup_one_len_common(const char *name, struct dentry *base,
if (!len)
return -EACCES;

- if (unlikely(name[0] == '.')) {
- if (len < 2 || (len == 2 && name[1] == '.'))
- return -EACCES;
- }
+ if (is_dot_dotdot(this))
+ return -EACCES;

while (len--) {
unsigned int c = *(const unsigned char *)name++;
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 98e0349..78a2932 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -3627,4 +3627,14 @@ static inline int inode_drain_writes(struct inode *inode)
return filemap_write_and_wait(inode->i_mapping);
}

+static inline bool is_dot_dotdot(const struct qstr *str)
+{
+ if (unlikely(str->name[0] == '.')) {
+ if (str->len < 2 || (str->len == 2 && str->name[1] == '.'))
+ return true;
+ }
+
+ return false;
+}
+
#endif /* _LINUX_FS_H */
--
2.1.0
\
 
 \ /
  Last update: 2019-12-03 13:58    [W:0.051 / U:12.320 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site