[PATCH] gconv: Fix assertion failure in ISO-2022-JP-3 module (bug 27256)
Florian Weimer
fweimer@redhat.com
Wed Jan 27 12:39:43 GMT 2021
The conversion loop to the internal encoding does not follow
the interface contract that __GCONV_FULL_OUTPUT is only returned
after the internal wchar_t buffer has been filled completely. This
is enforced by the first of the two asserts in iconv/skeleton.c:
/* We must run out of output buffer space in this
rerun. */
assert (outbuf == outerr);
assert (nstatus == __GCONV_FULL_OUTPUT);
This commit solves this issue by queuing a second wide character
which cannot be written immediately in the state variable, like
other converters already do (e.g., BIG5-HKSCS or TSCII).
Reported-by: Tavis Ormandy <taviso@gmail.com>
---
Thanks to Andreas Schwab and Bruno Haible for off-list review. We
decided that no embargo was needed.
iconvdata/Makefile | 4 +-
iconvdata/bug-iconv14.c | 127 ++++++++++++++++++++++++++++++++++++++++++++++
iconvdata/iso-2022-jp-3.c | 67 +++++++++++++++++-------
3 files changed, 178 insertions(+), 20 deletions(-)
diff --git a/iconvdata/Makefile b/iconvdata/Makefile
index c8c532a3e4..55c527a5f7 100644
--- a/iconvdata/Makefile
+++ b/iconvdata/Makefile
@@ -74,7 +74,7 @@ ifeq (yes,$(build-shared))
tests = bug-iconv1 bug-iconv2 tst-loading tst-e2big tst-iconv4 bug-iconv4 \
tst-iconv6 bug-iconv5 bug-iconv6 tst-iconv7 bug-iconv8 bug-iconv9 \
bug-iconv10 bug-iconv11 bug-iconv12 tst-iconv-big5-hkscs-to-2ucs4 \
- bug-iconv13
+ bug-iconv13 bug-iconv14
ifeq ($(have-thread-library),yes)
tests += bug-iconv3
endif
@@ -322,6 +322,8 @@ $(objpfx)bug-iconv10.out: $(objpfx)gconv-modules \
$(addprefix $(objpfx),$(modules.so))
$(objpfx)bug-iconv12.out: $(objpfx)gconv-modules \
$(addprefix $(objpfx),$(modules.so))
+$(objpfx)bug-iconv14.out: $(objpfx)gconv-modules \
+ $(addprefix $(objpfx),$(modules.so))
$(objpfx)iconv-test.out: run-iconv-test.sh $(objpfx)gconv-modules \
$(addprefix $(objpfx),$(modules.so)) \
diff --git a/iconvdata/bug-iconv14.c b/iconvdata/bug-iconv14.c
new file mode 100644
index 0000000000..902f140fa9
--- /dev/null
+++ b/iconvdata/bug-iconv14.c
@@ -0,0 +1,127 @@
+/* Assertion in ISO-2022-JP-3 due to two-character sequence (bug 27256).
+ Copyright (C) 2021 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
+ <https://www.gnu.org/licenses/>. */
+
+#include <iconv.h>
+#include <string.h>
+#include <errno.h>
+#include <support/check.h>
+
+/* Use an escape sequence to return to the initial state. */
+static void
+with_escape_sequence (void)
+{
+ iconv_t c = iconv_open ("UTF-8", "ISO-2022-JP-3");
+ TEST_VERIFY_EXIT (c != (iconv_t) -1);
+
+ char in[] = "\e$(O+D\e(B";
+ char *inbuf = in;
+ size_t inleft = strlen (in);
+ char out[3]; /* Space for one output character. */
+ char *outbuf;
+ size_t outleft;
+
+ outbuf = out;
+ outleft = sizeof (out);
+ TEST_COMPARE (iconv (c, &inbuf, &inleft, &outbuf, &outleft), (size_t) -1);
+ TEST_COMPARE (errno, E2BIG);
+ TEST_COMPARE (inleft, 3);
+ TEST_COMPARE (inbuf - in, strlen (in) - 3);
+ TEST_COMPARE (outleft, sizeof (out) - 2);
+ TEST_COMPARE (outbuf - out, 2);
+ TEST_COMPARE (out[0] & 0xff, 0xc3);
+ TEST_COMPARE (out[1] & 0xff, 0xa6);
+
+ /* Return to the initial shift state, producing the pending
+ character. */
+ outbuf = out;
+ outleft = sizeof (out);
+ TEST_COMPARE (iconv (c, &inbuf, &inleft, &outbuf, &outleft), 0);
+ TEST_COMPARE (inleft, 0);
+ TEST_COMPARE (inbuf - in, strlen (in));
+ TEST_COMPARE (outleft, sizeof (out) - 2);
+ TEST_COMPARE (outbuf - out, 2);
+ TEST_COMPARE (out[0] & 0xff, 0xcc);
+ TEST_COMPARE (out[1] & 0xff, 0x80);
+
+ /* Nothing should be flushed the second time. */
+ outbuf = out;
+ outleft = sizeof (out);
+ TEST_COMPARE (iconv (c, NULL, 0, &outbuf, &outleft), 0);
+ TEST_COMPARE (outleft, sizeof (out));
+ TEST_COMPARE (outbuf - out, 0);
+ TEST_COMPARE (out[0] & 0xff, 0xcc);
+ TEST_COMPARE (out[1] & 0xff, 0x80);
+
+ TEST_COMPARE (iconv_close (c), 0);
+}
+
+/* Use an explicit flush to return to the initial state. */
+static void
+with_flush (void)
+{
+ iconv_t c = iconv_open ("UTF-8", "ISO-2022-JP-3");
+ TEST_VERIFY_EXIT (c != (iconv_t) -1);
+
+ char in[] = "\e$(O+D";
+ char *inbuf = in;
+ size_t inleft = strlen (in);
+ char out[3]; /* Space for one output character. */
+ char *outbuf;
+ size_t outleft;
+
+ outbuf = out;
+ outleft = sizeof (out);
+ TEST_COMPARE (iconv (c, &inbuf, &inleft, &outbuf, &outleft), (size_t) -1);
+ TEST_COMPARE (errno, E2BIG);
+ TEST_COMPARE (inleft, 0);
+ TEST_COMPARE (inbuf - in, strlen (in));
+ TEST_COMPARE (outleft, sizeof (out) - 2);
+ TEST_COMPARE (outbuf - out, 2);
+ TEST_COMPARE (out[0] & 0xff, 0xc3);
+ TEST_COMPARE (out[1] & 0xff, 0xa6);
+
+ /* Flush the pending character. */
+ outbuf = out;
+ outleft = sizeof (out);
+ TEST_COMPARE (iconv (c, NULL, 0, &outbuf, &outleft), 0);
+ TEST_COMPARE (outleft, sizeof (out) - 2);
+ TEST_COMPARE (outbuf - out, 2);
+ TEST_COMPARE (out[0] & 0xff, 0xcc);
+ TEST_COMPARE (out[1] & 0xff, 0x80);
+
+ /* Nothing should be flushed the second time. */
+ outbuf = out;
+ outleft = sizeof (out);
+ TEST_COMPARE (iconv (c, NULL, 0, &outbuf, &outleft), 0);
+ TEST_COMPARE (outleft, sizeof (out));
+ TEST_COMPARE (outbuf - out, 0);
+ TEST_COMPARE (out[0] & 0xff, 0xcc);
+ TEST_COMPARE (out[1] & 0xff, 0x80);
+
+ TEST_COMPARE (iconv_close (c), 0);
+}
+
+static int
+do_test (void)
+{
+ with_escape_sequence ();
+ with_flush ();
+ return 0;
+}
+
+#include <support/test-driver.c>
diff --git a/iconvdata/iso-2022-jp-3.c b/iconvdata/iso-2022-jp-3.c
index 3eaa847ad9..c8ba88cdc9 100644
--- a/iconvdata/iso-2022-jp-3.c
+++ b/iconvdata/iso-2022-jp-3.c
@@ -67,23 +67,34 @@ enum
CURRENT_SEL_MASK = 7 << 3
};
-/* During UCS-4 to ISO-2022-JP-3 conversion, the COUNT element of the state
- also contains the last two bytes to be output, shifted by 6 bits, and a
- one-bit indicator whether they must be preceded by the shift sequence,
- in bit 22. */
+/* During UCS-4 to ISO-2022-JP-3 conversion, the COUNT element of the
+ state also contains the last two bytes to be output, shifted by 6
+ bits, and a one-bit indicator whether they must be preceded by the
+ shift sequence, in bit 22. During ISO-2022-JP-3 to UCS-4
+ conversion, COUNT may also contain a non-zero pending wide
+ character, shifted by six bits. This happens for certain inputs in
+ JISX0213_1_2004_set and JISX0213_2_set if the second wide character
+ in a combining sequence cannot be written because the buffer is
+ full. */
/* Since this is a stateful encoding we have to provide code which resets
the output state to the initial state. This has to be done during the
flushing. */
#define EMIT_SHIFT_TO_INIT \
- if ((data->__statep->__count & ~7) != ASCII_set) \
+ if (data->__statep->__count != ASCII_set) \
{ \
if (FROM_DIRECTION) \
{ \
- /* It's easy, we don't have to emit anything, we just reset the \
- state for the input. */ \
- data->__statep->__count &= 7; \
- data->__statep->__count |= ASCII_set; \
+ if (__glibc_likely (outbuf + 4 <= outend)) \
+ { \
+ /* Write out the last character. */ \
+ *((uint32_t *) outbuf) = data->__statep->__count >> 6; \
+ outbuf += sizeof (uint32_t); \
+ data->__statep->__count = ASCII_set; \
+ } \
+ else \
+ /* We don't have enough room in the output buffer. */ \
+ status = __GCONV_FULL_OUTPUT; \
} \
else \
{ \
@@ -151,7 +162,21 @@ enum
#define LOOPFCT FROM_LOOP
#define BODY \
{ \
- uint32_t ch = *inptr; \
+ uint32_t ch; \
+ \
+ /* Output any pending character. */ \
+ ch = set >> 6; \
+ if (__glibc_unlikely (ch != 0)) \
+ { \
+ put32 (outptr, ch); \
+ outptr += 4; \
+ /* Remove the pending character, but preserve state bits. */ \
+ set &= (1 << 6) - 1; \
+ continue; \
+ } \
+ \
+ /* Otherwise read the next input byte. */ \
+ ch = *inptr; \
\
/* Recognize escape sequences. */ \
if (__glibc_unlikely (ch == ESC)) \
@@ -297,21 +322,25 @@ enum
uint32_t u1 = __jisx0213_to_ucs_combining[ch - 1][0]; \
uint32_t u2 = __jisx0213_to_ucs_combining[ch - 1][1]; \
\
+ inptr += 2; \
+ \
+ put32 (outptr, u1); \
+ outptr += 4; \
+ \
/* See whether we have room for two characters. */ \
- if (outptr + 8 <= outend) \
+ if (outptr + 4 <= outend) \
{ \
- inptr += 2; \
- put32 (outptr, u1); \
- outptr += 4; \
put32 (outptr, u2); \
outptr += 4; \
continue; \
} \
- else \
- { \
- result = __GCONV_FULL_OUTPUT; \
- break; \
- } \
+ \
+ /* Otherwise store only the first character now, and \
+ put the second one into the queue. */ \
+ set |= u2 << 6; \
+ /* Tell the caller why we terminate the loop. */ \
+ result = __GCONV_FULL_OUTPUT; \
+ break; \
} \
\
inptr += 2; \
--
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