From: Dan Carpenter <dan.carpenter@linaro.org>
Date: Mon, 30 Oct 2023 09:02:59 +0000 (+0300)
Subject: crypto: rsa - add a check for allocation failure
X-Git-Tag: v6.6.14~541
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=2831f4d3bfa68e64c5f83e96688be779c87b3511;p=platform%2Fkernel%2Flinux-starfive.git

crypto: rsa - add a check for allocation failure

[ Upstream commit d872ca165cb67112f2841ef9c37d51ef7e63d1e4 ]

Static checkers insist that the mpi_alloc() allocation can fail so add
a check to prevent a NULL dereference.  Small allocations like this
can't actually fail in current kernels, but adding a check is very
simple and makes the static checkers happy.

Fixes: 6637e11e4ad2 ("crypto: rsa - allow only odd e and restrict value in FIPS mode")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

diff --git a/crypto/rsa.c b/crypto/rsa.c
index c79613c..b9cd11f 100644
--- a/crypto/rsa.c
+++ b/crypto/rsa.c
@@ -220,6 +220,8 @@ static int rsa_check_exponent_fips(MPI e)
 	}
 
 	e_max = mpi_alloc(0);
+	if (!e_max)
+		return -ENOMEM;
 	mpi_set_bit(e_max, 256);
 
 	if (mpi_cmp(e, e_max) >= 0) {