[RFC PATCH 17/20] ntfs: Do not use broken utf8 NLS table for iocharset=utf8 mount option
From: Pali Rohár <pali@kernel.org>
Date: 2021-08-08 16:25:37
Also in:
linux-fsdevel, lkml
Subsystem:
filesystems (vfs and infrastructure), ntfs filesystem, the rest · Maintainers:
Alexander Viro, Christian Brauner, Namjae Jeon, Hyunchul Lee, Linus Torvalds
NLS table for utf8 is broken and cannot be fixed. So instead of broken utf8 nls functions char2uni() and uni2char() use functions utf8s_to_utf16s() and utf16s_to_utf8s() which implements correct conversion between UTF-16 and UTF-8. These functions implements also correct processing of UTF-16 surrogate pairs and therefore after this change ntfs driver would be able to correctly handle also file names with 4-byte UTF-8 sequences. When iochatset=utf8 is used then set vol->nls_map 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/ntfs/dir.c | 6 ++++-- fs/ntfs/inode.c | 5 ++++- fs/ntfs/super.c | 41 ++++++++++++++++++++++++----------------- fs/ntfs/unistr.c | 27 ++++++++++++++++++++++++--- 4 files changed, 56 insertions(+), 23 deletions(-)
diff --git a/fs/ntfs/dir.c b/fs/ntfs/dir.c
index cd96083a12c8..035582b92aa2 100644
--- a/fs/ntfs/dir.c
+++ b/fs/ntfs/dir.c@@ -1034,7 +1034,8 @@ static inline int ntfs_filldir(ntfs_volume *vol, } name_len = ntfs_ucstonls(vol, (ntfschar*)&ie->key.file_name.file_name, ie->key.file_name.file_name_length, &name, - NTFS_MAX_NAME_LEN * NLS_MAX_CHARSET_SIZE + 1); + NTFS_MAX_NAME_LEN * + (vol->nls_map ? NLS_MAX_CHARSET_SIZE : 4) + 1); if (name_len <= 0) { ntfs_warning(vol->sb, "Skipping unrepresentable inode 0x%llx.", (long long)MREF_LE(ie->data.dir.indexed_file));
@@ -1118,7 +1119,8 @@ static int ntfs_readdir(struct file *file, struct dir_context *actor) * Allocate a buffer to store the current name being processed * converted to format determined by current NLS. */ - name = kmalloc(NTFS_MAX_NAME_LEN * NLS_MAX_CHARSET_SIZE + 1, GFP_NOFS); + name = kmalloc(NTFS_MAX_NAME_LEN * + (vol->nls_map ? NLS_MAX_CHARSET_SIZE : 4) + 1, GFP_NOFS); if (unlikely(!name)) { err = -ENOMEM; goto err_out;
diff --git a/fs/ntfs/inode.c b/fs/ntfs/inode.c
index 3676f185b4a0..1437944be66d 100644
--- a/fs/ntfs/inode.c
+++ b/fs/ntfs/inode.c@@ -2303,7 +2303,10 @@ int ntfs_show_options(struct seq_file *sf, struct dentry *root) seq_printf(sf, ",fmask=0%o", vol->fmask); seq_printf(sf, ",dmask=0%o", vol->dmask); } - seq_printf(sf, ",iocharset=%s", vol->nls_map->charset); + if (vol->nls_map) + seq_printf(sf, ",iocharset=%s", vol->nls_map->charset); + else + seq_puts(sf, ",iocharset=utf8"); if (NVolCaseSensitive(vol)) seq_printf(sf, ",case_sensitive"); if (NVolShowSystemFiles(vol))
diff --git a/fs/ntfs/super.c b/fs/ntfs/super.c
index 69c7871b742e..358f5e9e3c46 100644
--- a/fs/ntfs/super.c
+++ b/fs/ntfs/super.c@@ -84,7 +84,7 @@ static int simple_getbool(char *s, bool *setval) * * Parse the recognized options in @opt for the ntfs volume described by @vol. */ -static bool parse_options(ntfs_volume *vol, char *opt) +static bool parse_options(ntfs_volume *vol, char *opt, int remount) { char *p, *v, *ov; static char *utf8 = "utf8";
@@ -95,6 +95,7 @@ static bool parse_options(ntfs_volume *vol, char *opt) int mft_zone_multiplier = -1, on_errors = -1; int show_sys_files = -1, case_sensitive = -1, disable_sparse = -1; struct nls_table *nls_map = NULL; + int have_iocharset = 0; /* I am lazy... (-8 */ #define NTFS_GETOPT_WITH_DEFAULT(option, variable, default_value) \
@@ -196,12 +197,16 @@ static bool parse_options(ntfs_volume *vol, char *opt) goto needs_arg; use_utf8: unload_nls(nls_map); - nls_map = load_nls(v); - if (!nls_map) { - ntfs_error(vol->sb, "NLS character set " - "%s not found.", v); - return false; + nls_map = NULL; + if (strcmp(v, "utf8") != 0) { + nls_map = load_nls(v); + if (!nls_map) { + ntfs_error(vol->sb, "NLS character set " + "%s not found.", v); + return false; + } } + have_iocharset = 1; } else if (!strcmp(p, "utf8")) { bool val = false; ntfs_warning(vol->sb, "Option utf8 is no longer "
@@ -241,25 +246,27 @@ static bool parse_options(ntfs_volume *vol, char *opt) return false; } } - if (nls_map) { - if (vol->nls_map && vol->nls_map != nls_map) { + if (have_iocharset) { + if (remount && vol->nls_map != nls_map) { ntfs_error(vol->sb, "Cannot change NLS character set " "on remount."); return false; - } /* else (!vol->nls_map) */ - ntfs_debug("Using NLS character set %s.", nls_map->charset); - vol->nls_map = nls_map; - } else /* (!nls_map) */ { - if (!vol->nls_map) { + } else (!remount) { + ntfs_debug("Using NLS character set %s.", + nls_map ? nls_map->charset : "utf8"); + vol->nls_map = nls_map; + } + } else if (!remount) { + if (strcmp(CONFIG_NLS_DEFAULT, "utf8") != 0) { vol->nls_map = load_nls_default(); if (!vol->nls_map) { ntfs_error(vol->sb, "Failed to load default " "NLS character set."); return false; } - ntfs_debug("Using default NLS character set (%s).", - vol->nls_map->charset); } + ntfs_debug("Using default NLS character set (%s).", + vol->nls_map ? vol->nls_map->charset : "utf8"); } if (mft_zone_multiplier != -1) { if (vol->mft_zone_multiplier && vol->mft_zone_multiplier !=
@@ -534,7 +541,7 @@ static int ntfs_remount(struct super_block *sb, int *flags, char *opt) // TODO: Deal with *flags. - if (!parse_options(vol, opt)) + if (!parse_options(vol, opt, 1)) return -EINVAL; ntfs_debug("Done.");
@@ -2731,7 +2738,7 @@ static int ntfs_fill_super(struct super_block *sb, void *opt, const int silent) NVolSetSparseEnabled(vol); /* Important to get the mount options dealt with now. */ - if (!parse_options(vol, (char*)opt)) + if (!parse_options(vol, (char*)opt, 0)) goto err_out_now; /* We support sector sizes up to the PAGE_SIZE. */
diff --git a/fs/ntfs/unistr.c b/fs/ntfs/unistr.c
index 75a7f73bccdd..f29d83fb09bb 100644
--- a/fs/ntfs/unistr.c
+++ b/fs/ntfs/unistr.c@@ -254,6 +254,16 @@ int ntfs_nlstoucs(const ntfs_volume *vol, const char *ins, if (likely(ins)) { ucs = kmem_cache_alloc(ntfs_name_cache, GFP_NOFS); if (likely(ucs)) { + if (!nls) { + wc_len = utf8s_to_utf16s(ins, ins_len, + UTF16_LITTLE_ENDIAN, ucs, + NTFS_MAX_NAME_LEN); + if (wc_len < 0 || wc_len >= NTFS_MAX_NAME_LEN) + goto name_err; + ucs[wc_len] = 0; + *outs = ucs; + return o; + } for (i = o = 0; i < ins_len; i += wc_len) { wc_len = nls->char2uni(ins + i, ins_len - i, &wc);
@@ -283,7 +293,7 @@ int ntfs_nlstoucs(const ntfs_volume *vol, const char *ins, if (wc_len < 0) { ntfs_error(vol->sb, "Name using character set %s contains " "characters that cannot be converted to " - "Unicode.", nls->charset); + "Unicode.", nls ? nls->charset : "utf8"); i = -EILSEQ; } else /* if (o >= NTFS_MAX_NAME_LEN) */ { ntfs_error(vol->sb, "Name is too long (maximum length for a "
@@ -335,11 +345,22 @@ int ntfs_ucstonls(const ntfs_volume *vol, const ntfschar *ins, goto conversion_err; } if (!ns) { - ns_len = ins_len * NLS_MAX_CHARSET_SIZE; + ns_len = ins_len * (nls ? NLS_MAX_CHARSET_SIZE : 4); ns = kmalloc(ns_len + 1, GFP_NOFS); if (!ns) goto mem_err_out; } + if (!nls) { + o = utf16s_to_utf8s(ins, ins_len, UTF16_LITTLE_ENDIAN, + ns, ns_len); + if (o >= ns_len) { + wc = -ENAMETOOLONG; + goto conversion_err; + } + ns[o] = 0; + *outs = ns; + return o; + } for (i = o = 0; i < ins_len; i++) { retry: wc = nls->uni2char(le16_to_cpu(ins[i]), ns + o, ns_len - o);
@@ -373,7 +394,7 @@ retry: wc = nls->uni2char(le16_to_cpu(ins[i]), ns + o, ntfs_error(vol->sb, "Unicode name contains characters that cannot be " "converted to character set %s. You might want to " "try to use the mount option iocharset=utf8.", - nls->charset); + nls ? nls->charset : "utf8"); if (ns != *outs) kfree(ns); if (wc != -ENAMETOOLONG)
--
2.20.1