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authorArnd Bergmann <arnd@arndb.de>2019-06-18 13:19:42 +0200
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2019-07-31 07:28:30 +0200
commit46e4dbc33843c26954d4f5a9883ed4e430c42935 (patch)
tree211f082661572f7e1e1fa4ed2f1d36e8234a3af5 /crypto
parent1d458f4e358a35b796e290d5deaae66da532c12a (diff)
crypto: serpent - mark __serpent_setkey_sbox noinline
[ Upstream commit 473971187d6727609951858c63bf12b0307ef015 ] 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> Reviewed-by: Eric Biggers <ebiggers@kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'crypto')
-rw-r--r--crypto/serpent_generic.c8
1 files changed, 7 insertions, 1 deletions
diff --git a/crypto/serpent_generic.c b/crypto/serpent_generic.c
index 7c3382facc82..600bd288881d 100644
--- a/crypto/serpent_generic.c
+++ b/crypto/serpent_generic.c
@@ -229,7 +229,13 @@
x4 ^= x2; \
})
-static void __serpent_setkey_sbox(u32 r0, u32 r1, u32 r2, u32 r3, u32 r4, u32 *k)
+/*
+ * both gcc and clang have misoptimized this function in the past,
+ * producing horrible object code from spilling temporary variables
+ * on the stack. Forcing this part out of line avoids that.
+ */
+static noinline void __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);