Fix crashes on invalid input in IBM gconv modules [BZ #17325]
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Message ID 54008EF8.7030507@redhat.com
State New
Headers show

Commit Message

Florian Weimer Aug. 29, 2014, 2:32 p.m. UTC
On 08/29/2014 03:33 PM, Andreas Schwab wrote:
> Florian Weimer <fweimer@redhat.com> writes:
>
>> +	if (__builtin_expect (rp2->start == 0xffff, 0)			      \
>
> Please use either this
>
>> +	if (__builtin_expect (ch == 0xffff, 0)				      \
>
> or this consistently.

Oops, you are right.  I went with the first variant, as in the original fix.

Retested successfully.

Allan, is this okay for master at this stage?

Comments

Ondřej Bílka Aug. 30, 2014, 11:45 a.m. UTC | #1
On Fri, Aug 29, 2014 at 04:32:24PM +0200, Florian Weimer wrote:
> On 08/29/2014 03:33 PM, Andreas Schwab wrote:
> >Florian Weimer <fweimer@redhat.com> writes:
> >
> >>+	if (__builtin_expect (rp2->start == 0xffff, 0)			      \
> >
> >Please use either this
> >
> >>+	if (__builtin_expect (ch == 0xffff, 0)				      \
> >
> >or this consistently.
> 
> Oops, you are right.  I went with the first variant, as in the original fix.
> 
> Retested successfully.
> 
> Allan, is this okay for master at this stage?
> 
Anyway when we go for consistency wouldn't be better just use
libc_likely/unlikely?
Allan McRae Sept. 1, 2014, 12:33 a.m. UTC | #2
On 30/08/14 00:32, Florian Weimer wrote:
> On 08/29/2014 03:33 PM, Andreas Schwab wrote:
>> Florian Weimer <fweimer@redhat.com> writes:
>>
>>> +    if (__builtin_expect (rp2->start == 0xffff, 0)                  \
>>
>> Please use either this
>>
>>> +    if (__builtin_expect (ch == 0xffff, 0)                      \
>>
>> or this consistently.
> 
> Oops, you are right.  I went with the first variant, as in the original
> fix.
> 
> Retested successfully.
> 
> Allan, is this okay for master at this stage?
> 

I am OK with this, once there is an ack to use __builtin_expect instead
of __glibc_likely.

I agree with you that the cleanup of all the  __builtin_expect should
happen in a following patch so the change is minimal at this stage and
easy to backport.

Allan

Patch
diff mbox

From 1819abce68402c06b43621a4168828bb95c40bc1 Mon Sep 17 00:00:00 2001
From: Florian Weimer <fweimer@redhat.com>
Date: Fri, 29 Aug 2014 13:16:49 +0200
Subject: [PATCH] Fix crashes on invalid input in IBM gconv modules [BZ #17325]

These changes are based on the fix for BZ #14134 in commit
6e230d11837f3ae7b375ea69d7905f0d18eb79e5.

2014-08-29  Florian Weimer  <fweimer@redhat.com>

	[BZ #17325]
	* iconvdata/ibm1364.c (BODY): Fix check for sentinel.
	* iconvdata/ibm932.c (BODY): Replace invalid sentinel check with
	assert.
	* iconvdata/ibm933.c (BODY): Fix check for sentinel.
	* iconvdata/ibm935.c (BODY): Likewise.
	* iconvdata/ibm937.c (BODY): Likewise.
	* iconvdata/ibm939.c (BODY): Likewise.
	* iconvdata/ibm943.c (BODY): Replace invalid sentinel check with
	assert.
	* iconvdata/Makefile (iconv-test.out): Pass module list to test
	script.
	* iconvdata/run-iconv-test.sh: New test loop for checking for
	decoder crashers.

diff --git a/NEWS b/NEWS
index 1af9e70..dd93f2f 100644
--- a/NEWS
+++ b/NEWS
@@ -23,7 +23,7 @@  Version 2.20
   16966, 16967, 16977, 16978, 16984, 16990, 16996, 17009, 17022, 17031,
   17042, 17048, 17050, 17058, 17061, 17062, 17069, 17075, 17078, 17079,
   17084, 17086, 17088, 17092, 17097, 17125, 17135, 17137, 17150, 17153,
-  17187, 17213, 17259, 17261, 17262, 17263, 17319.
+  17187, 17213, 17259, 17261, 17262, 17263, 17319, 17325.
 
 * Reverted change of ABI data structures for s390 and s390x:
   On s390 and s390x the size of struct ucontext and jmp_buf was increased in
@@ -115,6 +115,11 @@  Version 2.20
   normal gconv conversion modules are still supported.  Transliteration
   with //TRANSLIT is still possible, and the //IGNORE specifier
   continues to be  supported. (CVE-2014-5119)
+
+* Decoding a crafted input sequence in the character sets IBM933, IBM935,
+  IBM937, IBM939, IBM1364 could result in an out-of-bounds array read,
+  resulting a denial-of-service security vulnerability in applications which
+  use functions related to iconv.
 
 Version 2.19
 
diff --git a/iconvdata/Makefile b/iconvdata/Makefile
index 0a410a1..b6327d6 100644
--- a/iconvdata/Makefile
+++ b/iconvdata/Makefile
@@ -297,6 +297,7 @@  $(objpfx)tst-iconv7.out: $(objpfx)gconv-modules \
 $(objpfx)iconv-test.out: run-iconv-test.sh $(objpfx)gconv-modules \
 			 $(addprefix $(objpfx),$(modules.so)) \
 			 $(common-objdir)/iconv/iconv_prog TESTS
+	iconv_modules="$(modules)" \
 	$(SHELL) $< $(common-objdir) '$(test-wrapper-env)' \
 		 '$(run-program-env)' > $@; \
 	$(evaluate-test)
diff --git a/iconvdata/ibm1364.c b/iconvdata/ibm1364.c
index 0b5484f..cf80993 100644
--- a/iconvdata/ibm1364.c
+++ b/iconvdata/ibm1364.c
@@ -221,7 +221,8 @@  enum
 	  ++rp2;							      \
 									      \
 	uint32_t res;							      \
-	if (__builtin_expect (ch < rp2->start, 0)			      \
+	if (__builtin_expect (rp2->start == 0xffff, 0)			      \
+	    || __builtin_expect (ch < rp2->start, 0)			      \
 	    || (res = DB_TO_UCS4[ch + rp2->idx],			      \
 		__builtin_expect (res, L'\1') == L'\0' && ch != '\0'))	      \
 	  {								      \
diff --git a/iconvdata/ibm932.c b/iconvdata/ibm932.c
index f5dca59..aa69d65 100644
--- a/iconvdata/ibm932.c
+++ b/iconvdata/ibm932.c
@@ -74,11 +74,12 @@ 
 	  }								      \
 									      \
 	ch = (ch * 0x100) + inptr[1];					      \
+	/* ch was less than 0xfd.  */					      \
+	assert (ch < 0xfd00);						      \
 	while (ch > rp2->end)						      \
 	  ++rp2;							      \
 									      \
-	if (__builtin_expect (rp2 == NULL, 0)				      \
-	    || __builtin_expect (ch < rp2->start, 0)			      \
+	if (__builtin_expect (ch < rp2->start, 0)			      \
 	    || (res = __ibm932db_to_ucs4[ch + rp2->idx],		      \
 	    __builtin_expect (res, '\1') == 0 && ch !=0))		      \
 	  {								      \
diff --git a/iconvdata/ibm933.c b/iconvdata/ibm933.c
index f46dfb5..461fb5e 100644
--- a/iconvdata/ibm933.c
+++ b/iconvdata/ibm933.c
@@ -162,7 +162,7 @@  enum
 	while (ch > rp2->end)						      \
 	  ++rp2;							      \
 									      \
-	if (__builtin_expect (rp2 == NULL, 0)				      \
+	if (__builtin_expect (rp2->start == 0xffff, 0)			      \
 	    || __builtin_expect (ch < rp2->start, 0)			      \
 	    || (res = __ibm933db_to_ucs4[ch + rp2->idx],		      \
 		__builtin_expect (res, L'\1') == L'\0' && ch != '\0'))	      \
diff --git a/iconvdata/ibm935.c b/iconvdata/ibm935.c
index a8e4e6c..132d816 100644
--- a/iconvdata/ibm935.c
+++ b/iconvdata/ibm935.c
@@ -162,7 +162,7 @@  enum
 	while (ch > rp2->end)						      \
 	  ++rp2;							      \
 									      \
-	if (__builtin_expect (rp2 == NULL, 0)				      \
+	if (__builtin_expect (rp2->start == 0xffff, 0)			      \
 	    || __builtin_expect (ch < rp2->start, 0)			      \
 	    || (res = __ibm935db_to_ucs4[ch + rp2->idx],		      \
 		__builtin_expect (res, L'\1') == L'\0' && ch != '\0'))	      \
diff --git a/iconvdata/ibm937.c b/iconvdata/ibm937.c
index 239be61..69b154d 100644
--- a/iconvdata/ibm937.c
+++ b/iconvdata/ibm937.c
@@ -162,7 +162,7 @@  enum
 	while (ch > rp2->end)						      \
 	  ++rp2;							      \
 									      \
-	if (__builtin_expect (rp2 == NULL, 0)				      \
+	if (__builtin_expect (rp2->start == 0xffff, 0)			      \
 	    || __builtin_expect (ch < rp2->start, 0)			      \
 	    || (res = __ibm937db_to_ucs4[ch + rp2->idx],		      \
 		__builtin_expect (res, L'\1') == L'\0' && ch != '\0'))	      \
diff --git a/iconvdata/ibm939.c b/iconvdata/ibm939.c
index 5d0db36..9936e2c 100644
--- a/iconvdata/ibm939.c
+++ b/iconvdata/ibm939.c
@@ -162,7 +162,7 @@  enum
 	while (ch > rp2->end)						      \
 	  ++rp2;							      \
 									      \
-	if (__builtin_expect (rp2 == NULL, 0)				      \
+	if (__builtin_expect (rp2->start == 0xffff, 0)			      \
 	    || __builtin_expect (ch < rp2->start, 0)			      \
 	    || (res = __ibm939db_to_ucs4[ch + rp2->idx],		      \
 		__builtin_expect (res, L'\1') == L'\0' && ch != '\0'))	      \
diff --git a/iconvdata/ibm943.c b/iconvdata/ibm943.c
index be0c14f..c5d5742 100644
--- a/iconvdata/ibm943.c
+++ b/iconvdata/ibm943.c
@@ -75,11 +75,12 @@ 
 	  }								      \
 									      \
 	ch = (ch * 0x100) + inptr[1];					      \
+	/* ch was less than 0xfd.  */					      \
+	assert (ch < 0xfd00);						      \
 	while (ch > rp2->end)						      \
 	  ++rp2;							      \
 									      \
-	if (__builtin_expect (rp2 == NULL, 0)				      \
-	    || __builtin_expect (ch < rp2->start, 0)			      \
+	if (__builtin_expect (ch < rp2->start, 0)			      \
 	    || (res = __ibm943db_to_ucs4[ch + rp2->idx],		      \
 	    __builtin_expect (res, '\1') == 0 && ch !=0))		      \
 	  {								      \
diff --git a/iconvdata/run-iconv-test.sh b/iconvdata/run-iconv-test.sh
index c98c929..5dfb69f 100755
--- a/iconvdata/run-iconv-test.sh
+++ b/iconvdata/run-iconv-test.sh
@@ -184,6 +184,24 @@  while read utf8 from filename; do
 
 done < TESTS2
 
+# Check for crashes in decoders.
+printf '\016\377\377\377\377\377\377\377' > $temp1
+for from in $iconv_modules ; do
+    echo $ac_n "test decoder $from $ac_c"
+    PROG=`eval echo $ICONV`
+    if $PROG < $temp1 >/dev/null 2>&1 ; then
+	: # fall through
+    else
+	status=$?
+	if test $status -gt 1 ; then
+	    echo "/FAILED"
+	    failed=1
+	    continue
+	fi
+    fi
+    echo "OK"
+done
+
 exit $failed
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 #  mode:shell-script
-- 
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