[PATCH 5.7 120/204] crypto: af_alg - Fix regression on empty requests

Greg Kroah-Hartman
2020-08-20T09:40:33Z

From: Herbert Xu <herbert@gondor.apana.org.au>

[ Upstream commit 662bb52f50bca16a74fe92b487a14d7dccb85e1a ]

Some user-space programs rely on crypto requests that have no
control metadata. This broke when a check was added to require
the presence of control metadata with the ctx->init flag.

This patch fixes the regression by setting ctx->init as long as
one sendmsg(2) has been made, with or without a control message.

Reported-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Fixes: f3c802a1f300 ("crypto: algif_aead - Only wake up when...")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
crypto/af_alg.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/crypto/af_alg.c b/crypto/af_alg.c
index 9fcb91ea10c41..5882ed46f1adb 100644
--- a/crypto/af_alg.c
+++ b/crypto/af_alg.c
@@ -851,6 +851,7 @@ int af_alg_sendmsg(struct socket *sock, struct msghdr *msg, size_t size,
err = -EINVAL;
goto unlock;
}
+ ctx->init = true;

if (init) {
ctx->enc = enc;
@@ -858,7 +859,6 @@ int af_alg_sendmsg(struct socket *sock, struct msghdr *msg, size_t size,
memcpy(ctx->iv, con.iv->iv, ivsize);

ctx->aead_assoclen = con.aead_assoclen;
- ctx->init = true;
}

while (size) {
--
2.25.1