From patchwork Tue Sep 10 09:08:08 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andreas Schwab X-Patchwork-Id: 34463 Received: (qmail 100006 invoked by alias); 10 Sep 2019 09:08:12 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Delivered-To: mailing list libc-alpha@sourceware.org Received: (qmail 99998 invoked by uid 89); 10 Sep 2019 09:08:12 -0000 Authentication-Results: sourceware.org; auth=none X-Spam-SWARE-Status: No, score=-15.3 required=5.0 tests=AWL, BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, KAM_SHORT, SPF_PASS autolearn=ham version=3.3.1 spammy= X-HELO: mx1.suse.de From: Andreas Schwab To: libc-alpha@sourceware.org Subject: [PATCH v2] Fix buffer overrun in EUC-KR conversion module (bug 24973) References: X-Yow: I'll show you MY telex number if you show me YOURS... Date: Tue, 10 Sep 2019 11:08:08 +0200 In-Reply-To: (Andreas Schwab's message of "Mon, 09 Sep 2019 17:58:12 +0200") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.3 (gnu/linux) MIME-Version: 1.0 The byte 0xfe as input to the EUC-KR conversion denotes a user-defined area and is not allowed. The from_euc_kr function used to skip two bytes when told to skip over the unknown designation, potentially running over the buffer end. [BZ #24973] * iconvdata/ksc5601.h (ksc5601_to_ucs4): Check for available bytes first. * iconvdata/euc-kr.c (BODY for FROM_LOOP): Don't check for unknown two-byte codes here. * iconvdata/Makefile (tests): Add bug-iconv13. * iconvdata/bug-iconv13.c: New file. --- iconvdata/Makefile | 2 +- iconvdata/bug-iconv13.c | 53 +++++++++++++++++++++++++++++++++++++++++ iconvdata/euc-kr.c | 6 +---- iconvdata/ksc5601.h | 6 ++--- 4 files changed, 58 insertions(+), 9 deletions(-) create mode 100644 iconvdata/bug-iconv13.c diff --git a/iconvdata/Makefile b/iconvdata/Makefile index 763ef05389..5dac816857 100644 --- a/iconvdata/Makefile +++ b/iconvdata/Makefile @@ -73,7 +73,7 @@ modules.so := $(addsuffix .so, $(modules)) ifeq (yes,$(build-shared)) tests = bug-iconv1 bug-iconv2 tst-loading tst-e2big tst-iconv4 bug-iconv4 \ tst-iconv6 bug-iconv5 bug-iconv6 tst-iconv7 bug-iconv8 bug-iconv9 \ - bug-iconv10 bug-iconv11 bug-iconv12 + bug-iconv10 bug-iconv11 bug-iconv12 bug-iconv13 ifeq ($(have-thread-library),yes) tests += bug-iconv3 endif diff --git a/iconvdata/bug-iconv13.c b/iconvdata/bug-iconv13.c new file mode 100644 index 0000000000..e879e4fe14 --- /dev/null +++ b/iconvdata/bug-iconv13.c @@ -0,0 +1,53 @@ +/* bug 24973: Test EUC-KR module + Copyright (C) 2019 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#include +#include +#include +#include + +static int +do_test (void) +{ + iconv_t cd = iconv_open ("UTF-8//IGNORE", "EUC-KR"); + TEST_VERIFY_EXIT (cd != (iconv_t) -1); + + /* 0xfe (->0x7e : row 94) and 0xc9 (->0x49 : row 41) are user-defined + areas, which are not allowed and should be skipped over due to + //IGNORE. The trailing 0xfe also is an incomplete sequence, which + should be checked first. */ + char input[4] = { '\xc9', '\xa1', '\0', '\xfe' }; + char *inptr = input; + size_t insize = sizeof (input); + char output[4]; + char *outptr = output; + size_t outsize = sizeof (output); + + /* This used to crash due to buffer overrun. */ + TEST_VERIFY (iconv (cd, &inptr, &insize, &outptr, &outsize) == (size_t) -1); + TEST_VERIFY (errno == EINVAL); + /* The conversion should produce one character, the converted null + character. */ + TEST_VERIFY (sizeof (output) - outsize == 1); + + TEST_VERIFY_EXIT (iconv_close (cd) != -1); + + return 0; +} + +#include diff --git a/iconvdata/euc-kr.c b/iconvdata/euc-kr.c index 379414c426..54ab362e8e 100644 --- a/iconvdata/euc-kr.c +++ b/iconvdata/euc-kr.c @@ -80,11 +80,7 @@ euckr_from_ucs4 (uint32_t ch, unsigned char *cp) \ if (ch <= 0x9f) \ ++inptr; \ - /* 0xfe(->0x7e : row 94) and 0xc9(->0x59 : row 41) are \ - user-defined areas. */ \ - else if (__builtin_expect (ch == 0xa0, 0) \ - || __builtin_expect (ch > 0xfe, 0) \ - || __builtin_expect (ch == 0xc9, 0)) \ + else if (__glibc_unlikely (ch == 0xa0)) \ { \ /* This is illegal. */ \ STANDARD_FROM_LOOP_ERR_HANDLER (1); \ diff --git a/iconvdata/ksc5601.h b/iconvdata/ksc5601.h index 5582cc8deb..c3c39661d5 100644 --- a/iconvdata/ksc5601.h +++ b/iconvdata/ksc5601.h @@ -50,15 +50,15 @@ ksc5601_to_ucs4 (const unsigned char **s, size_t avail, unsigned char offset) unsigned char ch2; int idx; + if (avail < 2) + return 0; + /* row 94(0x7e) and row 41(0x49) are user-defined area in KS C 5601 */ if (ch < offset || (ch - offset) <= 0x20 || (ch - offset) >= 0x7e || (ch - offset) == 0x49) return __UNKNOWN_10646_CHAR; - if (avail < 2) - return 0; - ch2 = (*s)[1]; if (ch2 < offset || (ch2 - offset) <= 0x20 || (ch2 - offset) >= 0x7f) return __UNKNOWN_10646_CHAR;