| Message ID | 20240911144502.115260-2-andrealmeid@igalia.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | tmpfs: Add case-insensitive support for tmpfs | expand |
André Almeida <andrealmeid@igalia.com> writes: > Create a helper function for filesystems do the checks required for > casefold directories and strict encoding. > > Suggested-by: Gabriel Krisman Bertazi <gabriel@krisman.be> > Signed-off-by: André Almeida <andrealmeid@igalia.com> > --- > Changes from v2: > - Moved function to libfs and adpated its name > - Wrapped at 72 chars column > - Decomposed the big if (...) to be more clear > --- > fs/libfs.c | 38 ++++++++++++++++++++++++++++++++++++++ > include/linux/fs.h | 1 + > 2 files changed, 39 insertions(+) > > diff --git a/fs/libfs.c b/fs/libfs.c > index 8aa34870449f..99fb36b48708 100644 > --- a/fs/libfs.c > +++ b/fs/libfs.c > @@ -1928,6 +1928,44 @@ int generic_ci_match(const struct inode *parent, > return !res; > } > EXPORT_SYMBOL(generic_ci_match); > + > +/** > + * generic_ci_validate_strict_name - Check if a given name is suitable > + * for a directory > + * > + * This functions checks if the proposed filename is valid for the > + * parent directory. That means that only valid UTF-8 filenames will be > + * accepted for casefold directories from filesystems created with the > + * strict encoding flag. That also means that any name will be > + * accepted for directories that doesn't have casefold enabled, or > + * aren't being strict with the encoding. > + * > + * @dir: inode of the directory where the new file will be created > + * @name: name of the new file > + * > + * Return: > + * * True if the filename is suitable for this directory. It can be > + * true if a given name is not suitable for a strict encoding > + * directory, but the directory being used isn't strict > + * * False if the filename isn't suitable for this directory. This only > + * happens when a directory is casefolded and the filesystem is strict > + * about its encoding. > + */ > +bool generic_ci_validate_strict_name(struct inode *dir, struct qstr *name) > +{ > + if (!IS_CASEFOLDED(dir) || !sb_has_strict_encoding(dir->i_sb)) > + return true; > + > + /* > + * A casefold dir must have a encoding set, unless the filesystem > + * is corrupted > + */ > + if (WARN_ON_ONCE(!dir->i_sb->s_encoding)) > + return true; > + > + return utf8_validate(dir->i_sb->s_encoding, name); > +} > +EXPORT_SYMBOL(generic_ci_validate_strict_name); > #endif > > #ifdef CONFIG_FS_ENCRYPTION > diff --git a/include/linux/fs.h b/include/linux/fs.h > index fd34b5755c0b..937142950dfe 100644 > --- a/include/linux/fs.h > +++ b/include/linux/fs.h > @@ -3385,6 +3385,7 @@ extern int generic_ci_match(const struct inode *parent, > const struct qstr *name, > const struct qstr *folded_name, > const u8 *de_name, u32 de_name_len); > +bool generic_ci_validate_strict_name(struct inode *dir, struct qstr *name); As mentioned in the other patch, please make this an inline helper. But also, the declaration needs to be guarded by CONFIG_UNICODE. > > static inline bool sb_has_encoding(const struct super_block *sb) > {
diff --git a/fs/libfs.c b/fs/libfs.c index 8aa34870449f..99fb36b48708 100644 --- a/fs/libfs.c +++ b/fs/libfs.c @@ -1928,6 +1928,44 @@ int generic_ci_match(const struct inode *parent, return !res; } EXPORT_SYMBOL(generic_ci_match); + +/** + * generic_ci_validate_strict_name - Check if a given name is suitable + * for a directory + * + * This functions checks if the proposed filename is valid for the + * parent directory. That means that only valid UTF-8 filenames will be + * accepted for casefold directories from filesystems created with the + * strict encoding flag. That also means that any name will be + * accepted for directories that doesn't have casefold enabled, or + * aren't being strict with the encoding. + * + * @dir: inode of the directory where the new file will be created + * @name: name of the new file + * + * Return: + * * True if the filename is suitable for this directory. It can be + * true if a given name is not suitable for a strict encoding + * directory, but the directory being used isn't strict + * * False if the filename isn't suitable for this directory. This only + * happens when a directory is casefolded and the filesystem is strict + * about its encoding. + */ +bool generic_ci_validate_strict_name(struct inode *dir, struct qstr *name) +{ + if (!IS_CASEFOLDED(dir) || !sb_has_strict_encoding(dir->i_sb)) + return true; + + /* + * A casefold dir must have a encoding set, unless the filesystem + * is corrupted + */ + if (WARN_ON_ONCE(!dir->i_sb->s_encoding)) + return true; + + return utf8_validate(dir->i_sb->s_encoding, name); +} +EXPORT_SYMBOL(generic_ci_validate_strict_name); #endif #ifdef CONFIG_FS_ENCRYPTION diff --git a/include/linux/fs.h b/include/linux/fs.h index fd34b5755c0b..937142950dfe 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -3385,6 +3385,7 @@ extern int generic_ci_match(const struct inode *parent, const struct qstr *name, const struct qstr *folded_name, const u8 *de_name, u32 de_name_len); +bool generic_ci_validate_strict_name(struct inode *dir, struct qstr *name); static inline bool sb_has_encoding(const struct super_block *sb) {
Create a helper function for filesystems do the checks required for casefold directories and strict encoding. Suggested-by: Gabriel Krisman Bertazi <gabriel@krisman.be> Signed-off-by: André Almeida <andrealmeid@igalia.com> --- Changes from v2: - Moved function to libfs and adpated its name - Wrapped at 72 chars column - Decomposed the big if (...) to be more clear --- fs/libfs.c | 38 ++++++++++++++++++++++++++++++++++++++ include/linux/fs.h | 1 + 2 files changed, 39 insertions(+)