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>
---
Changes since v1:
- add Fixes and Reviewed-by tags

Note: This patch should be applied to the x86 platform drivers tree.
---
 fs/nls/nls_base.c | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/fs/nls/nls_base.c b/fs/nls/nls_base.c
index d434c4463a8f..a5c3a9f1b8dc 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);
 
-- 
2.39.5

On Sat, 29 Nov 2025 12:15:35 +0100, Armin Wolf wrote:

> 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.
> 
> 
> [...]


Thank you for your contribution, it has been applied to my local
review-ilpo-next branch. Note it will show up in the public
platform-drivers-x86/review-ilpo-next branch only once I've pushed my
local branch there, which might take a while.

The list of commits applied:
[1/1] fs/nls: Fix inconsistency between utf8_to_utf32() and utf32_to_utf8()
      commit: c36f9d7b2869a003a2f7d6ff2c6bac9e62fd7d68

--
 i.