Bug#633458: gcc-4.6 miscompiles libgcrypt11 on armel
On 2011-07-14 Matthias Klose wrote: > On 07/14/2011 08:17 PM, Andreas Metzler wrote: > > (sid)ametzler@abel:~/GNUTLS/GCR/libgcrypt11-1.4.6$ > > ~/GNUTLS/2.10.5-2/usr/bin/gnutls-cli db.debian.org > > Resolving 'db.debian.org'... > > Connecting to '82.195.75.106:443'... > > *** Fatal error: Decryption has failed. > > *** Handshake has failed > > GnuTLS error: Decryption has failed. > > --- > > > > ~/GNUTLS/2.10.5-2/ is not a local build, I just extracted (dpkg -x) the > > official deb since abel does not have gnutls-bin installed. > strange. this does work for me on a local machine (Ubuntu 11.04 kernel, armv7 > processor, Genesi Efika MX), sid chroot I have no idea why that is the case. It is 100% reproducible on abel. Anyway, I have just uploaded libgcrypt11 1.4.6-8 including the attached workaround. cu andreas -- `What a good friend you are to him, Dr. Maturin. His other friends are so grateful to you.' `I sew his ears on from time to time, sure' Description: Disable inlining on do_decrypt_aligned() on ARM. This works around gcc issue #633458, which had broken gnutls on ARM. Author: Andreas Metzler Bug-Debian: http://bugs.debian.org/633458 --- libgcrypt11-1.4.6.orig/cipher/rijndael.c +++ libgcrypt11-1.4.6/cipher/rijndael.c @@ -569,6 +569,9 @@ _gcry_aes_cbc_enc (void *context, unsign /* Decrypt one block. A and B need to be aligned on a 4 byte boundary and the decryption must have been prepared. A and B may be the same. */ +#ifdef ARMWORKAROUND633458 +__attribute__((noinline)) +#endif static void do_decrypt_aligned (RIJNDAEL_context *ctx, unsigned char *b, const unsigned char *a)
Bug#633458: gcc-4.6 miscompiles libgcrypt11 on armel
On 2011-07-14 Matthias Klose wrote:
> On 07/12/2011 07:56 PM, Andreas Metzler wrote:
> > On 2011-07-10 Andreas Metzler wrote:
[...]
> >>> Building with -fno-strict-aliasing does not help.
[...]
> maybe try not to inline, or turn off an optimization for this
> specific function(s). Then the assembler output of a working and a
> non-working function would help.
> __attribute__((noinline))
> __attribute__((optimize("O0")))
> __attribute__((optimize("no-inline")))
> __attribute__((optimize("no-strict-aliasing")))
> see
> http://gcc.gnu.org/onlinedocs/gcc-4.6.1/gcc/Function-Attributes.html#Function-Attributes
Hello,
[helps]Building rijndael.c with -O0
[nochange] Building rijndael.c with -O1
[nochange] Building rijndael.c (or all gcrypt) with
-fno-strict-aliasing
[helps]Building rijndael.c with -fno-inline
[helps]Setting __attribute__((noinline)) on do_decrypt_aligned [1]
[nochange] Setting __attribute__((noinline)) on do_decrypt
[helps]Setting __attribute__((optimize("O0"))) on do_decrypt_aligned
[helps]Setting __attribute__((optimize("O0"))) on do_decrypt
[helps]Setting __attribute__((optimize("no-inline"))) on do_decrypt_aligned
[helps]Setting __attribute__((optimize("no-inline"))) on do_decrypt
[...]
For which of these would like to see further info, and how exactly
should I generate it?
thanks, cu andreas
[1] Example diff:
-
--- ../rijndael.c.orig 2011-07-14 17:56:54.0 +
+++ cipher/rijndael.c 2011-07-15 17:54:46.0 +
@@ -569,7 +569,7 @@ _gcry_aes_cbc_enc (void *context, unsign
/* Decrypt one block. A and B need to be aligned on a 4 byte boundary
and the decryption must have been prepared. A and B may be the
same. */
-static void
+__attribute__((noinline)) static void
do_decrypt_aligned (RIJNDAEL_context *ctx,
unsigned char *b, const unsigned char *a)
{
--
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Bug#633458: gcc-4.6 miscompiles libgcrypt11 on armel
On 07/14/2011 08:17 PM, Andreas Metzler wrote: > (sid)ametzler@abel:~/GNUTLS/GCR/libgcrypt11-1.4.6$ > ~/GNUTLS/2.10.5-2/usr/bin/gnutls-cli db.debian.org > Resolving 'db.debian.org'... > Connecting to '82.195.75.106:443'... > *** Fatal error: Decryption has failed. > *** Handshake has failed > GnuTLS error: Decryption has failed. > --- > > ~/GNUTLS/2.10.5-2/ is not a local build, I just extracted (dpkg -x) the > official deb since abel does not have gnutls-bin installed. strange. this does work for me on a local machine (Ubuntu 11.04 kernel, armv7 processor, Genesi Efika MX), sid chroot -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org
Bug#633458: gcc-4.6 miscompiles libgcrypt11 on armel
On 2011-07-14 Matthias Klose wrote: > On 07/12/2011 07:56 PM, Andreas Metzler wrote: [...] > >> The culprit is cipher/rijndael.c. If I build this file with > >> gcc-4.5 the bug goes away. > > I do not know how to go on now. > could you recheck with 4.6.1-3 and gcc-snapshot? > is this exposed on armhf as well (CC'ing Markos)? No difference with either 4.6.1-3 or gcc-snapshot 20110709-1. (Removing the two "static" still fixes the testcase.) [ deleted some stuff I will try later this week ] > the binary in the archive seems to work. gcc-4.6.0-13 was used for > the build. [...] Actually, it does not: --- +++-==-==- ii gcc-4.64.6.1-3GNU C compiler ii libgcrypt111.4.6-7LGPL Crypto library - runtime library ii libgnutls262.10.5-2 the GNU TLS library - runtime library (sid)ametzler@abel:~/GNUTLS/GCR/libgcrypt11-1.4.6$ ~/GNUTLS/2.10.5-2/usr/bin/gnutls-cli db.debian.org Resolving 'db.debian.org'... Connecting to '82.195.75.106:443'... *** Fatal error: Decryption has failed. *** Handshake has failed GnuTLS error: Decryption has failed. --- ~/GNUTLS/2.10.5-2/ is not a local build, I just extracted (dpkg -x) the official deb since abel does not have gnutls-bin installed. cu andreas -- `What a good friend you are to him, Dr. Maturin. His other friends are so grateful to you.' `I sew his ears on from time to time, sure' -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org
Bug#633458: gcc-4.6 miscompiles libgcrypt11 on armel
On 07/12/2011 07:56 PM, Andreas Metzler wrote:
> On 2011-07-10 Andreas Metzler wrote:
>> On 2011-07-10 Andreas Metzler wrote:
>>> On 2011-07-10 Andreas Metzler wrote:
Package: gcc-4.6
Version: 4.6.1-1
Severity: normal
Blocks: 633373
>
gcc-4.6 seems to miscompile libgcrypt11 on armel, causing total
failure of gnutls26.
>
---
(sid)ametzler@abel:~/GNUTLS$ ~/GNUTLS/2.10.5-2/usr/bin/gnutls-cli
db.debian.org Resolving 'db.debian.org'...
Connecting to '82.195.75.106:443'...
*** Fatal error: Decryption has failed.
*** Handshake has failed
GnuTLS error: Decryption has failed.
---
>>> [...]
>
>>> Building with -fno-strict-aliasing does not help.
>> [...]
>
>> The culprit is cipher/rijndael.c. If I build this file with
>> gcc-4.5 the bug goes away.
>
> Hello,
>
> I do not know how to go on now.
could you recheck with 4.6.1-3 and gcc-snapshot?
is this exposed on armhf as well (CC'ing Markos)?
> What I tried was splitting rijndael.c into multiple separate files.
> However this made the error go away.
>
> It seems that the significant change I made when spliting was
> dropping the static qualifier on the function declarations.
maybe try not to inline, or turn off an optimization for this specific
function(s). Then the assembler output of a working and a non-working function
would help.
__attribute__((noinline))
__attribute__((optimize("O0")))
__attribute__((optimize("no-inline")))
__attribute__((optimize("no-strict-aliasing")))
see
http://gcc.gnu.org/onlinedocs/gcc-4.6.1/gcc/Function-Attributes.html#Function-Attributes
>
> The minimal change I found to make my testcase (gnutls-cli
> db.debian.org) go away was dropping the static qualifier from these
> two functions:
>
>
> /* Decrypt one block. A and B need to be aligned on a 4 byte boundary
>and the decryption must have been prepared. A and B may be the
>same. */
> static void
> do_decrypt_aligned (RIJNDAEL_context *ctx,
> unsigned char *b, const unsigned char *a)
>
>
> /* Decrypt one block. AX and BX may be the same. */
> static void
> do_decrypt (RIJNDAEL_context *ctx, byte *bx, const byte *ax)
>
the binary in the archive seems to work. gcc-4.6.0-13 was used for the build.
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Bug#633458: gcc-4.6 miscompiles libgcrypt11 on armel
On 2011-07-10 Andreas Metzler wrote: > On 2011-07-10 Andreas Metzler wrote: > > On 2011-07-10 Andreas Metzler wrote: > > > Package: gcc-4.6 > > > Version: 4.6.1-1 > > > Severity: normal > > > Blocks: 633373 > > > gcc-4.6 seems to miscompile libgcrypt11 on armel, causing total > > > failure of gnutls26. > > > --- > > > (sid)ametzler@abel:~/GNUTLS$ ~/GNUTLS/2.10.5-2/usr/bin/gnutls-cli > > > db.debian.org Resolving 'db.debian.org'... > > > Connecting to '82.195.75.106:443'... > > > *** Fatal error: Decryption has failed. > > > *** Handshake has failed > > > GnuTLS error: Decryption has failed. > > > --- > > [...] > > Building with -fno-strict-aliasing does not help. > [...] > The culprit is cipher/rijndael.c. If I build this file with > gcc-4.5 the bug goes away. Hello, I do not know how to go on now. What I tried was splitting rijndael.c into multiple separate files. However this made the error go away. It seems that the significant change I made when spliting was dropping the static qualifier on the function declarations. The minimal change I found to make my testcase (gnutls-cli db.debian.org) go away was dropping the static qualifier from these two functions: /* Decrypt one block. A and B need to be aligned on a 4 byte boundary and the decryption must have been prepared. A and B may be the same. */ static void do_decrypt_aligned (RIJNDAEL_context *ctx, unsigned char *b, const unsigned char *a) /* Decrypt one block. AX and BX may be the same. */ static void do_decrypt (RIJNDAEL_context *ctx, byte *bx, const byte *ax) cu andreas -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org
Bug#633458: gcc-4.6 miscompiles libgcrypt11 on armel
On 2011-07-10 Andreas Metzler wrote: > On 2011-07-10 Andreas Metzler wrote: > > Package: gcc-4.6 > > Version: 4.6.1-1 > > Severity: normal > > Blocks: 633373 > > gcc-4.6 seems to miscompile libgcrypt11 on armel, causing total > > failure of gnutls26. > > --- > > (sid)ametzler@abel:~/GNUTLS$ ~/GNUTLS/2.10.5-2/usr/bin/gnutls-cli > > db.debian.org Resolving 'db.debian.org'... > > Connecting to '82.195.75.106:443'... > > *** Fatal error: Decryption has failed. > > *** Handshake has failed > > GnuTLS error: Decryption has failed. > > --- > [...] > Building with -fno-strict-aliasing does not help. [...] The culprit is cipher/rijndael.c. If I build this file with gcc-4.5 the bug goes away. cu andreas -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org
Bug#633458: gcc-4.6 miscompiles libgcrypt11 on armel
On 2011-07-10 Andreas Metzler wrote: > Package: gcc-4.6 > Version: 4.6.1-1 > Severity: normal > Blocks: 633373 > gcc-4.6 seems to miscompile libgcrypt11 on armel, causing total > failure of gnutls26. > --- > (sid)ametzler@abel:~/GNUTLS$ ~/GNUTLS/2.10.5-2/usr/bin/gnutls-cli > db.debian.org Resolving 'db.debian.org'... > Connecting to '82.195.75.106:443'... > *** Fatal error: Decryption has failed. > *** Handshake has failed > GnuTLS error: Decryption has failed. > --- [...] Building with -fno-strict-aliasing does not help. running gnutls-cli with debugging provides a little bit more info on the code triggering the issue: [...] |<7>| RB: Requested 53 bytes |<2>| ASSERT: gnutls_cipher.c:530 |<4>| REC[0x2e338]: Short record length 166 > 48 - 20 (under attack?) [...] cu andreas -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org
Bug#633458: gcc-4.6 miscompiles libgcrypt11 on armel
Package: gcc-4.6 Version: 4.6.1-1 Severity: normal Blocks: 633373 gcc-4.6 seems to miscompile libgcrypt11 on armel, causing total failure of gnutls26. --- (sid)ametzler@abel:~/GNUTLS$ ~/GNUTLS/2.10.5-2/usr/bin/gnutls-cli db.debian.org Resolving 'db.debian.org'... Connecting to '82.195.75.106:443'... *** Fatal error: Decryption has failed. *** Handshake has failed GnuTLS error: Decryption has failed. --- libgcrypt11 1.4.6-5 (no source changes compared to 1.4.6-7, just a switch to multiarch directories) works: --- (sid)ametzler@abel:~/GNUTLS$ LD_LIBRARY_PATH=~/GNUTLS/gcr-1.4.6-5/lib ~/GNUTLS/ 2.10.5-2/usr/bin/gnutls-cli db.debian.org Resolving 'db.debian.org'... Connecting to '82.195.75.106:443'... - Ephemeral Diffie-Hellman parameters [...] - Handshake was completed --- I have also rebuilt libgcrypt11 with gcc-4.5, this also fixed the issue: --- LD_LIBRARY_PATH=/home/ametzler/GNUTLS/GCR/libgcrypt11-1.4.6+gcc45/src/.libs ~/GNUTLS/2.10.5-2/usr/bin/gnutls-cli db.debian.org Resolving 'db.debian.org'... Connecting to '82.195.75.106:443'... - Ephemeral Diffie-Hellman parameters [...] - Handshake was completed --- All tests done in the sid chroot of the Debian porterbox (abel). cu andreas ii gcc4:4.6.0-6 GNU C compiler ii gcc-4.54.5.3-3The GNU C compiler ii gcc-4.64.6.1-1GNU C compiler ii libgcrypt111.4.6-7LGPL Crypto library - runtime library ii libgnutls262.10.5-2 the GNU TLS library - runtime library ii libtasn1-3 2.9-4 Manage ASN.1 structures (runtime) -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org
