Linux cryptographic layer development
 help / color / mirror / Atom feed
From: Arnd Bergmann <arnd@arndb.de>
To: Herbert Xu <herbert@gondor.apana.org.au>,
	"David S. Miller" <davem@davemloft.net>
Cc: Arnd Bergmann <arnd@arndb.de>, Eric Biggers <ebiggers@google.com>,
	linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH] crypto: serpent - mark __serpent_setkey_sbox noinline
Date: Mon, 17 Jun 2019 13:59:08 +0200	[thread overview]
Message-ID: <20190617115927.3813471-1-arnd@arndb.de> (raw)

The same bug that gcc hit in the past is apparently now showing
up with clang, which decides to inline __serpent_setkey_sbox:

crypto/serpent_generic.c:268:5: error: stack frame size of 2112 bytes in function '__serpent_setkey' [-Werror,-Wframe-larger-than=]

Marking it 'noinline' reduces the stack usage from 2112 bytes to
192 and 96 bytes, respectively, and seems to generate more
useful object code.

Fixes: c871c10e4ea7 ("crypto: serpent - improve __serpent_setkey with UBSAN")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 crypto/serpent_generic.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/crypto/serpent_generic.c b/crypto/serpent_generic.c
index e57757904677..183661faf420 100644
--- a/crypto/serpent_generic.c
+++ b/crypto/serpent_generic.c
@@ -225,7 +225,7 @@
 	x4 ^= x2;					\
 	})
 
-static void __serpent_setkey_sbox(u32 r0, u32 r1, u32 r2, u32 r3, u32 r4, u32 *k)
+static void noinline __serpent_setkey_sbox(u32 r0, u32 r1, u32 r2, u32 r3, u32 r4, u32 *k)
 {
 	k += 100;
 	S3(r3, r4, r0, r1, r2); store_and_load_keys(r1, r2, r4, r3, 28, 24);
-- 
2.20.0


             reply	other threads:[~2019-06-17 11:59 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-06-17 11:59 Arnd Bergmann [this message]
2019-06-18  3:19 ` [PATCH] crypto: serpent - mark __serpent_setkey_sbox noinline Eric Biggers

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20190617115927.3813471-1-arnd@arndb.de \
    --to=arnd@arndb.de \
    --cc=davem@davemloft.net \
    --cc=ebiggers@google.com \
    --cc=herbert@gondor.apana.org.au \
    --cc=linux-crypto@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox