lkml.org 
[lkml]   [2022]   [Dec]   [26]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[RFC PATCH v2 11/18] hfsplus: Do not use broken utf8 NLS table for iocharset=utf8 mount option
Date
NLS table for utf8 is broken and cannot be fixed.

So instead of broken utf8 nls functions char2uni() and uni2char() use
functions utf8_to_utf32() and utf32_to_utf8() which implements correct
encoding and decoding between Unicode code points and UTF-8 sequence.

Note that this fs driver does not support full Unicode range, specially
UTF-16 surrogate pairs are unsupported. This patch does not change this
limitation and support for UTF-16 surrogate pairs stay unimplemented.

When iochatset=utf8 is used then set sbi->nls to NULL and use it for
distinguish between the fact if NLS table or native UTF-8 functions should
be used.

Signed-off-by: Pali Rohár <pali@kernel.org>
---
fs/hfsplus/dir.c | 7 +++++--
fs/hfsplus/options.c | 32 ++++++++++++++++++--------------
fs/hfsplus/super.c | 7 +------
fs/hfsplus/unicode.c | 31 ++++++++++++++++++++++++++++---
fs/hfsplus/xattr.c | 20 +++++++++++++-------
fs/hfsplus/xattr_security.c | 6 ++++--
6 files changed, 69 insertions(+), 34 deletions(-)

diff --git a/fs/hfsplus/dir.c b/fs/hfsplus/dir.c
index 84714bbccc12..b19cb6c34dd2 100644
--- a/fs/hfsplus/dir.c
+++ b/fs/hfsplus/dir.c
@@ -144,7 +144,9 @@ static int hfsplus_readdir(struct file *file, struct dir_context *ctx)
err = hfs_find_init(HFSPLUS_SB(sb)->cat_tree, &fd);
if (err)
return err;
- strbuf = kmalloc(NLS_MAX_CHARSET_SIZE * HFSPLUS_MAX_STRLEN + 1, GFP_KERNEL);
+ len = (HFSPLUS_SB(sb)->nls ? NLS_MAX_CHARSET_SIZE : 4) *
+ HFSPLUS_MAX_STRLEN + 1;
+ strbuf = kmalloc(len, GFP_KERNEL);
if (!strbuf) {
err = -ENOMEM;
goto out;
@@ -203,7 +205,8 @@ static int hfsplus_readdir(struct file *file, struct dir_context *ctx)
hfs_bnode_read(fd.bnode, &entry, fd.entryoffset,
fd.entrylength);
type = be16_to_cpu(entry.type);
- len = NLS_MAX_CHARSET_SIZE * HFSPLUS_MAX_STRLEN;
+ len = (HFSPLUS_SB(sb)->nls ? NLS_MAX_CHARSET_SIZE : 4) *
+ HFSPLUS_MAX_STRLEN;
err = hfsplus_uni2asc(sb, &fd.key->cat.name, strbuf, &len);
if (err)
goto out;
diff --git a/fs/hfsplus/options.c b/fs/hfsplus/options.c
index d3dc0d4ba77f..ede7776d1da9 100644
--- a/fs/hfsplus/options.c
+++ b/fs/hfsplus/options.c
@@ -104,6 +104,9 @@ int hfsplus_parse_options(char *input, struct hfsplus_sb_info *sbi)
char *p;
substring_t args[MAX_OPT_ARGS];
int tmp, token;
+ bool have_iocharset;
+
+ have_iocharset = false;

if (!input)
goto done;
@@ -175,20 +178,24 @@ int hfsplus_parse_options(char *input, struct hfsplus_sb_info *sbi)
pr_warn("option nls= is deprecated, use iocharset=\n");
fallthrough;
case opt_iocharset:
- if (sbi->nls) {
+ if (have_iocharset) {
pr_err("unable to change nls mapping\n");
return 0;
}
p = match_strdup(&args[0]);
- if (p)
- sbi->nls = load_nls(p);
- if (!sbi->nls) {
- pr_err("unable to load nls mapping \"%s\"\n",
- p);
- kfree(p);
+ if (!p)
return 0;
+ if (strcmp(p, "utf8") != 0) {
+ sbi->nls = load_nls(p);
+ if (!sbi->nls) {
+ pr_err("unable to load nls mapping "
+ "\"%s\"\n", p);
+ kfree(p);
+ return 0;
+ }
}
kfree(p);
+ have_iocharset = true;
break;
case opt_decompose:
clear_bit(HFSPLUS_SB_NODECOMPOSE, &sbi->flags);
@@ -211,13 +218,10 @@ int hfsplus_parse_options(char *input, struct hfsplus_sb_info *sbi)
}

done:
- if (!sbi->nls) {
- /* try utf8 first, as this is the old default behaviour */
- sbi->nls = load_nls("utf8");
- if (!sbi->nls)
- sbi->nls = load_nls_default();
- if (!sbi->nls)
- return 0;
+ if (!have_iocharset) {
+ /* use utf8, as this is the old default behaviour */
+ pr_debug("using native UTF-8 without nls\n");
+ /* no sbi->nls means that native UTF-8 code is used */
}

return 1;
diff --git a/fs/hfsplus/super.c b/fs/hfsplus/super.c
index 122ed89ebf9f..8a66a77ad3e1 100644
--- a/fs/hfsplus/super.c
+++ b/fs/hfsplus/super.c
@@ -403,11 +403,7 @@ static int hfsplus_fill_super(struct super_block *sb, void *data, int silent)

/* temporarily use utf8 to correctly find the hidden dir below */
nls = sbi->nls;
- sbi->nls = load_nls("utf8");
- if (!sbi->nls) {
- pr_err("unable to load nls for utf8\n");
- goto out_unload_nls;
- }
+ sbi->nls = NULL;

/* Grab the volume header */
if (hfsplus_read_wrapper(sb)) {
@@ -585,7 +581,6 @@ static int hfsplus_fill_super(struct super_block *sb, void *data, int silent)
}
}

- unload_nls(sbi->nls);
sbi->nls = nls;
return 0;

diff --git a/fs/hfsplus/unicode.c b/fs/hfsplus/unicode.c
index 73342c925a4b..dc9be40d049f 100644
--- a/fs/hfsplus/unicode.c
+++ b/fs/hfsplus/unicode.c
@@ -190,7 +190,12 @@ int hfsplus_uni2asc(struct super_block *sb,
c0 = ':';
break;
}
- res = nls->uni2char(c0, op, len);
+ if (nls)
+ res = nls->uni2char(c0, op, len);
+ else if (len > 0)
+ res = utf32_to_utf8(c0, op, len);
+ else
+ res = -ENAMETOOLONG;
if (res < 0) {
if (res == -ENAMETOOLONG)
goto out;
@@ -233,7 +238,12 @@ int hfsplus_uni2asc(struct super_block *sb,
cc = c0;
}
done:
- res = nls->uni2char(cc, op, len);
+ if (nls)
+ res = nls->uni2char(cc, op, len);
+ else if (len > 0)
+ res = utf32_to_utf8(cc, op, len);
+ else
+ res = -ENAMETOOLONG;
if (res < 0) {
if (res == -ENAMETOOLONG)
goto out;
@@ -256,7 +266,22 @@ int hfsplus_uni2asc(struct super_block *sb,
static inline int asc2unichar(struct super_block *sb, const char *astr, int len,
wchar_t *uc)
{
- int size = HFSPLUS_SB(sb)->nls->char2uni(astr, len, uc);
+ struct nls_table *nls = HFSPLUS_SB(sb)->nls;
+ unicode_t u;
+ int size;
+
+ if (nls)
+ size = nls->char2uni(astr, len, uc);
+ else {
+ size = utf8_to_utf32(astr, len, &u);
+ if (size >= 0) {
+ /* TODO: Add support for UTF-16 surrogate pairs */
+ if (u <= MAX_WCHAR_T)
+ *uc = u;
+ else
+ size = -EINVAL;
+ }
+ }
if (size <= 0) {
*uc = '?';
size = 1;
diff --git a/fs/hfsplus/xattr.c b/fs/hfsplus/xattr.c
index 49891b12c415..607f46b3d0f3 100644
--- a/fs/hfsplus/xattr.c
+++ b/fs/hfsplus/xattr.c
@@ -422,11 +422,13 @@ int hfsplus_setxattr(struct inode *inode, const char *name,
const void *value, size_t size, int flags,
const char *prefix, size_t prefixlen)
{
+ int xattr_name_len;
char *xattr_name;
int res;

- xattr_name = kmalloc(NLS_MAX_CHARSET_SIZE * HFSPLUS_ATTR_MAX_STRLEN + 1,
- GFP_KERNEL);
+ xattr_name_len = (HFSPLUS_SB(inode->i_sb)->nls ? NLS_MAX_CHARSET_SIZE : 4) *
+ HFSPLUS_ATTR_MAX_STRLEN + 1;
+ xattr_name = kmalloc(xattr_name_len, GFP_KERNEL);
if (!xattr_name)
return -ENOMEM;
strcpy(xattr_name, prefix);
@@ -578,9 +580,11 @@ ssize_t hfsplus_getxattr(struct inode *inode, const char *name,
{
int res;
char *xattr_name;
+ int xattr_name_len;

- xattr_name = kmalloc(NLS_MAX_CHARSET_SIZE * HFSPLUS_ATTR_MAX_STRLEN + 1,
- GFP_KERNEL);
+ xattr_name_len = (HFSPLUS_SB(inode->i_sb)->nls ? NLS_MAX_CHARSET_SIZE : 4) *
+ HFSPLUS_ATTR_MAX_STRLEN + 1;
+ xattr_name = kmalloc(xattr_name_len, GFP_KERNEL);
if (!xattr_name)
return -ENOMEM;

@@ -699,8 +703,9 @@ ssize_t hfsplus_listxattr(struct dentry *dentry, char *buffer, size_t size)
return err;
}

- strbuf = kmalloc(NLS_MAX_CHARSET_SIZE * HFSPLUS_ATTR_MAX_STRLEN +
- XATTR_MAC_OSX_PREFIX_LEN + 1, GFP_KERNEL);
+ xattr_name_len = (HFSPLUS_SB(inode->i_sb)->nls ? NLS_MAX_CHARSET_SIZE : 4) *
+ HFSPLUS_ATTR_MAX_STRLEN + XATTR_MAC_OSX_PREFIX_LEN + 1;
+ strbuf = kmalloc(xattr_name_len, GFP_KERNEL);
if (!strbuf) {
res = -ENOMEM;
goto out;
@@ -732,7 +737,8 @@ ssize_t hfsplus_listxattr(struct dentry *dentry, char *buffer, size_t size)
if (be32_to_cpu(attr_key.cnid) != inode->i_ino)
goto end_listxattr;

- xattr_name_len = NLS_MAX_CHARSET_SIZE * HFSPLUS_ATTR_MAX_STRLEN;
+ xattr_name_len = (HFSPLUS_SB(inode->i_sb)->nls ? NLS_MAX_CHARSET_SIZE : 4) *
+ HFSPLUS_ATTR_MAX_STRLEN;
if (hfsplus_uni2asc(inode->i_sb,
(const struct hfsplus_unistr *)&fd.key->attr.key_name,
strbuf, &xattr_name_len)) {
diff --git a/fs/hfsplus/xattr_security.c b/fs/hfsplus/xattr_security.c
index c1c7a16cbf21..b4b45c796ef4 100644
--- a/fs/hfsplus/xattr_security.c
+++ b/fs/hfsplus/xattr_security.c
@@ -38,11 +38,13 @@ static int hfsplus_initxattrs(struct inode *inode,
void *fs_info)
{
const struct xattr *xattr;
+ int xattr_name_len;
char *xattr_name;
int err = 0;

- xattr_name = kmalloc(NLS_MAX_CHARSET_SIZE * HFSPLUS_ATTR_MAX_STRLEN + 1,
- GFP_KERNEL);
+ xattr_name_len = (HFSPLUS_SB(inode->i_sb)->nls ? NLS_MAX_CHARSET_SIZE : 4) *
+ HFSPLUS_ATTR_MAX_STRLEN + 1;
+ xattr_name = kmalloc(xattr_name_len, GFP_KERNEL);
if (!xattr_name)
return -ENOMEM;
for (xattr = xattr_array; xattr->name != NULL; xattr++) {
--
2.20.1
\
 
 \ /
  Last update: 2023-03-26 23:20    [W:0.105 / U:1.620 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site