[RFC PATCH 16/20] jfs: Do not use broken utf8 NLS table for iocharset=utf8 mount option
From: Pali Rohár <pali@kernel.org>
Date: 2021-08-08 16:25:27
Also in:
linux-fsdevel, lkml
Subsystem:
filesystems (vfs and infrastructure), jfs filesystem, the rest · Maintainers:
Alexander Viro, Christian Brauner, Dave Kleikamp, 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 jfs driver would be able to correctly handle also file names with 4-byte UTF-8 sequences. When iochatset=utf8 is used then set sbi->nls_tab 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/jfs/jfs_unicode.c | 17 +++++++++++++++-- fs/jfs/super.c | 24 +++++++++++++++--------- 2 files changed, 30 insertions(+), 11 deletions(-)
diff --git a/fs/jfs/jfs_unicode.c b/fs/jfs/jfs_unicode.c
index 2db923872bf1..4c39b6b65bca 100644
--- a/fs/jfs/jfs_unicode.c
+++ b/fs/jfs/jfs_unicode.c@@ -46,6 +46,9 @@ int jfs_strfromUCS_le(char *to, int maxlen, const __le16 * from, } } } + } else { + outlen = utf16s_to_utf8s(from, len, + UTF16_LITTLE_ENDIAN, to, maxlen-1); } to[outlen] = 0; return outlen;
@@ -61,6 +64,7 @@ static int jfs_strtoUCS(wchar_t * to, const unsigned char *from, int len, struct nls_table *codepage) { int charlen; + int outlen; int i; if (codepage) {
@@ -75,10 +79,19 @@ static int jfs_strtoUCS(wchar_t * to, const unsigned char *from, int len, return charlen; } } + outlen = i; + } else { + outlen = utf8s_to_utf16s(from, len, UTF16_LITTLE_ENDIAN, + to, len); + if (outlen < 1) { + jfs_err("jfs_strtoUCS: utf8s_to_utf16s returned %d.", + outlen); + return outlen; + } } - to[i] = 0; - return i; + to[outlen] = 0; + return outlen; } /*
diff --git a/fs/jfs/super.c b/fs/jfs/super.c
index 8ba2ac032292..f449fdd56654 100644
--- a/fs/jfs/super.c
+++ b/fs/jfs/super.c@@ -261,16 +261,20 @@ static int parse_options(char *options, struct super_block *sb, s64 *newLVSize, /* Don't do anything ;-) */ break; case Opt_iocharset: - if (nls_map && nls_map != (void *) -1) + if (nls_map && nls_map != (void *) -1) { unload_nls(nls_map); - /* compatibility alias none means ISO-8859-1 */ - if (strcmp(args[0].from, "none") == 0) - nls_map = load_nls("iso8859-1"); - else - nls_map = load_nls(args[0].from); - if (!nls_map) { - pr_err("JFS: charset not found\n"); - goto cleanup; + nls_map = NULL; + } + if (strcmp(args[0].from, "utf8") != 0) { + /* compatibility alias none means ISO-8859-1 */ + if (strcmp(args[0].from, "none") == 0) + nls_map = load_nls("iso8859-1"); + else + nls_map = load_nls(args[0].from); + if (!nls_map) { + pr_err("JFS: charset not found\n"); + goto cleanup; + } } break; case Opt_resize:
@@ -718,6 +722,8 @@ static int jfs_show_options(struct seq_file *seq, struct dentry *root) seq_printf(seq, ",discard=%u", sbi->minblks_trim); if (sbi->nls_tab) seq_printf(seq, ",iocharset=%s", sbi->nls_tab->charset); + else + seq_puts(seq, ",iocharset=utf8"); if (sbi->flag & JFS_ERR_CONTINUE) seq_printf(seq, ",errors=continue"); if (sbi->flag & JFS_ERR_PANIC)
--
2.20.1