1 files changed, 39 insertions, 0 deletions

diff --git a/meta/recipes-support/libgcrypt/files/0001-ecc-Store-EdDSA-session-key-in-secure-memory.patch b/meta/recipes-support/libgcrypt/files/0001-ecc-Store-EdDSA-session-key-in-secure-memory.patch
new file mode 100644
index 0000000000..f6c4ca76f3
--- /dev/null
+++ b/meta/recipes-support/libgcrypt/files/0001-ecc-Store-EdDSA-session-key-in-secure-memory.patch
@@ -0,0 +1,39 @@
+CVE: CVE-2017-9526
+Upstream-Status: Backport
+Signed-off-by: Ross Burton <ross.burton@intel.com>
+
+From b3cab278eb9c2ceda79f980bc26460d97f260041 Mon Sep 17 00:00:00 2001
+From: Jo Van Bulck <jo.vanbulck@cs.kuleuven.be>
+Date: Thu, 19 Jan 2017 17:00:15 +0100
+Subject: [PATCH] ecc: Store EdDSA session key in secure memory.
+
+* cipher/ecc-eddsa.c (_gcry_ecc_eddsa_sign): use mpi_snew to allocate
+session key.
+--
+
+An attacker who learns the EdDSA session key from side-channel
+observation during the signing process, can easily revover the long-
+term secret key. Storing the session key in secure memory ensures that
+constant time point operations are used in the MPI library.
+
+Signed-off-by: Jo Van Bulck <jo.vanbulck@cs.kuleuven.be>
+---
+ cipher/ecc-eddsa.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/cipher/ecc-eddsa.c b/cipher/ecc-eddsa.c
+index f91f8489..813e030d 100644
+--- a/cipher/ecc-eddsa.c
++++ b/cipher/ecc-eddsa.c
+@@ -603,7 +603,7 @@ _gcry_ecc_eddsa_sign (gcry_mpi_t input, ECC_secret_key *skey,
+   a = mpi_snew (0);
+   x = mpi_new (0);
+   y = mpi_new (0);
+-  r = mpi_new (0);
++  r = mpi_snew (0);
+   ctx = _gcry_mpi_ec_p_internal_new (skey->E.model, skey->E.dialect, 0,
+                                      skey->E.p, skey->E.a, skey->E.b);
+   b = (ctx->nbits+7)/8;
+-- 
+2.11.0
+