[PATCH] crypto: sm2 - Fix crash caused by uninitialized context

From: Tianjia Zhang
Date: Mon Sep 18 2023 - 04:39:39 EST


In sm2_compute_z_digest() function, the newly allocated structure
mpi_ec_ctx is used, but forget to initialize it, which will cause
a crash when performing subsequent operations.

Fixes: e5221fa6a355 ("KEYS: asymmetric: Move sm2 code into x509_public_key")
Cc: stable@xxxxxxxxxxxxxxx # v6.5
Signed-off-by: Tianjia Zhang <tianjia.zhang@xxxxxxxxxxxxxxxxx>
---
crypto/sm2.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/crypto/sm2.c b/crypto/sm2.c
index 285b3cb7c0bc..5ab120d74c59 100644
--- a/crypto/sm2.c
+++ b/crypto/sm2.c
@@ -278,10 +278,14 @@ int sm2_compute_z_digest(struct shash_desc *desc,
if (!ec)
return -ENOMEM;

- err = __sm2_set_pub_key(ec, key, keylen);
+ err = sm2_ec_ctx_init(ec);
if (err)
goto out_free_ec;

+ err = __sm2_set_pub_key(ec, key, keylen);
+ if (err)
+ goto out_deinit_ec;
+
bits_len = SM2_DEFAULT_USERID_LEN * 8;
entl[0] = bits_len >> 8;
entl[1] = bits_len & 0xff;
--
2.24.3 (Apple Git-128)