linux-kernel - [PATCH] nls: remove "support" for 5- and 6-byte UTF-8 sequences

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [day] [month] [year] [list]

Message-ID: <20140728212643.GA27113@p183.telecom.by>
Date:	Tue, 29 Jul 2014 00:26:44 +0300
From:	Alexey Dobriyan <adobriyan@...il.com>
To:	akpm@...ux-foundation.org
Cc:	linux-kernel@...r.kernel.org
Subject: [PATCH] nls: remove "support" for 5- and 6-byte UTF-8 sequences

5- and 6-byte UTF-8 sequences existed to accomodate code points starting
from U+200000.

Those code points couldn't fit into old 2-byte wchar_t type.

Commit 74675a58507e769beee7d949dbed788af3c4139d added 16+ bit Unicode support
but started (correctly) to check for maximum valid code point
which is U+10FFFF.

U+10FFFF decodes into just 4-byte sequence.

5- and 6- byte UTF-8 sequences were made illegal long ago in
Unicode standard and never had a chance to be used in Linux,
so put them out of misery.

Signed-off-by: Alexey Dobriyan <adobriyan@...il.com>
---

 fs/nls/nls_base.c |    2 --
 1 file changed, 2 deletions(-)

--- a/fs/nls/nls_base.c
+++ b/fs/nls/nls_base.c
@@ -39,8 +39,6 @@ static const struct utf8_table utf8_table[] =
     {0xE0,  0xC0,   1*6,    0x7FF,          0x80,      /* 2 byte sequence */},
     {0xF0,  0xE0,   2*6,    0xFFFF,         0x800,     /* 3 byte sequence */},
     {0xF8,  0xF0,   3*6,    0x1FFFFF,       0x10000,   /* 4 byte sequence */},
-    {0xFC,  0xF8,   4*6,    0x3FFFFFF,      0x200000,  /* 5 byte sequence */},
-    {0xFE,  0xFC,   5*6,    0x7FFFFFFF,     0x4000000, /* 6 byte sequence */},
     {0,						       /* end of table    */}
 };
 
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/