From: Armin Wolf <W_Armin@gmx.de>
Date: Sat, 29 Nov 2025 11:15:35 +0000 (+0100)
Subject: fs/nls: Fix inconsistency between utf8_to_utf32() and utf32_to_utf8()
X-Git-Tag: v6.19-rc1~42^2~2
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=c36f9d7b2869a003a2f7d6ff2c6bac9e62fd7d68;p=thirdparty%2Flinux.git

fs/nls: Fix inconsistency between utf8_to_utf32() and utf32_to_utf8()

After commit 25524b619029 ("fs/nls: Fix utf16 to utf8 conversion"),
the return values of utf8_to_utf32() and utf32_to_utf8() are
inconsistent when encountering an error: utf8_to_utf32() returns -1,
while utf32_to_utf8() returns errno codes. Fix this inconsistency
by modifying utf8_to_utf32() to return errno codes as well.

Fixes: 25524b619029 ("fs/nls: Fix utf16 to utf8 conversion")
Suggested-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Signed-off-by: Armin Wolf <W_Armin@gmx.de>
Link: https://patch.msgid.link/20251129111535.8984-1-W_Armin@gmx.de
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
---

diff --git a/fs/nls/nls_base.c b/fs/nls/nls_base.c
index d434c4463a8f7..a5c3a9f1b8dc5 100644
--- a/fs/nls/nls_base.c
+++ b/fs/nls/nls_base.c
@@ -67,19 +67,22 @@ int utf8_to_utf32(const u8 *s, int inlen, unicode_t *pu)
 			l &= t->lmask;
 			if (l < t->lval || l > UNICODE_MAX ||
 					(l & SURROGATE_MASK) == SURROGATE_PAIR)
-				return -1;
+				return -EILSEQ;
+
 			*pu = (unicode_t) l;
 			return nc;
 		}
 		if (inlen <= nc)
-			return -1;
+			return -EOVERFLOW;
+
 		s++;
 		c = (*s ^ 0x80) & 0xFF;
 		if (c & 0xC0)
-			return -1;
+			return -EILSEQ;
+
 		l = (l << 6) | c;
 	}
-	return -1;
+	return -EILSEQ;
 }
 EXPORT_SYMBOL(utf8_to_utf32);