There exists many similar and duplicate codes to check "." and "..", so introduce is_dot_or_dotdot helper to make the code more clean.
Signed-off-by: Tiezhu Yang <yangtie...@loongson.cn> --- v5: - remove "qname" variable in fscrypt_fname_disk_to_usr() - modify "len < 2" to "len == 1" in is_dot_or_dotdot() v4: - rename is_dot_dotdot() to is_dot_or_dotdot() v3: - use "name" and "len" as arguments instead of qstr - move is_dot_dotdot() to include/linux/namei.h 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 | 17 +++-------------- fs/ecryptfs/crypto.c | 12 +----------- fs/f2fs/f2fs.h | 11 ----------- fs/f2fs/hash.c | 3 ++- fs/namei.c | 6 ++---- include/linux/namei.h | 10 ++++++++++ 6 files changed, 18 insertions(+), 41 deletions(-) diff --git a/fs/crypto/fname.c b/fs/crypto/fname.c index 3da3707..bb41f5d 100644 --- a/fs/crypto/fname.c +++ b/fs/crypto/fname.c @@ -11,21 +11,11 @@ * This has not yet undergone a rigorous security audit. */ +#include <linux/namei.h> #include <linux/scatterlist.h> #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 * @@ -252,10 +242,9 @@ int fscrypt_fname_disk_to_usr(struct inode *inode, const struct fscrypt_str *iname, struct fscrypt_str *oname) { - const struct qstr qname = FSTR_TO_QSTR(iname); struct fscrypt_digested_name digested_name; - if (fscrypt_is_dot_dotdot(&qname)) { + if (is_dot_or_dotdot(iname->name, iname->len)) { 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_or_dotdot(iname->name, iname->len)) { 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..c3bcbf0 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 @@ -2027,7 +2017,7 @@ 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_or_dotdot(name, name_size)) { 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/f2fs/hash.c b/fs/f2fs/hash.c index 5bc4dcd..ef155c2 100644 --- a/fs/f2fs/hash.c +++ b/fs/f2fs/hash.c @@ -15,6 +15,7 @@ #include <linux/cryptohash.h> #include <linux/pagemap.h> #include <linux/unicode.h> +#include <linux/namei.h> #include "f2fs.h" @@ -82,7 +83,7 @@ static f2fs_hash_t __f2fs_dentry_hash(const struct qstr *name_info, if (fname && !fname->disk_name.name) return cpu_to_le32(fname->hash); - if (is_dot_dotdot(name_info)) + if (is_dot_or_dotdot(name, len)) return 0; /* Initialize the default seed for the hash checksum functions */ diff --git a/fs/namei.c b/fs/namei.c index d6c91d1..f3a4439 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -2451,10 +2451,8 @@ 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_or_dotdot(name, len)) + return -EACCES; while (len--) { unsigned int c = *(const unsigned char *)name++; diff --git a/include/linux/namei.h b/include/linux/namei.h index 7fe7b87..0fd9315 100644 --- a/include/linux/namei.h +++ b/include/linux/namei.h @@ -92,4 +92,14 @@ retry_estale(const long error, const unsigned int flags) return error == -ESTALE && !(flags & LOOKUP_REVAL); } +static inline bool is_dot_or_dotdot(const unsigned char *name, size_t len) +{ + if (unlikely(name[0] == '.')) { + if (len == 1 || (len == 2 && name[1] == '.')) + return true; + } + + return false; +} + #endif /* _LINUX_NAMEI_H */ -- 2.1.0 _______________________________________________ Linux-f2fs-devel mailing list Linux-f2fs-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel