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From:   Roberto Sassu <roberto.sassu@huawei.com>
To:     <zohar@linux.ibm.com>, <mjg59@google.com>
CC:     <linux-integrity@vger.kernel.org>,
        <linux-security-module@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <silviu.vlasceanu@huawei.com>,
        Roberto Sassu <roberto.sassu@huawei.com>,
        <stable@vger.kernel.org>
Subject: [PATCH 10/11] ima: Don't ignore errors from crypto_shash_update()
Date:   Thu, 18 Jun 2020 18:04:57 +0200
Message-ID: <20200618160458.1579-10-roberto.sassu@huawei.com>
In-Reply-To: <20200618160329.1263-2-roberto.sassu@huawei.com>
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Errors returned by crypto_shash_update() are not checked in
ima_calc_boot_aggregate_tfm() and thus can be overwritten at the next
iteration of the loop. This patch adds a check after calling
crypto_shash_update() and returns immediately if the result is not zero.

Cc: stable@vger.kernel.org
Fixes: 3323eec921efd ("integrity: IMA as an integrity service provider")
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
---
 security/integrity/ima/ima_crypto.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/security/integrity/ima/ima_crypto.c b/security/integrity/ima/ima_crypto.c
index 220b14920c37..47897fbae6c6 100644
--- a/security/integrity/ima/ima_crypto.c
+++ b/security/integrity/ima/ima_crypto.c
@@ -829,6 +829,8 @@ static int ima_calc_boot_aggregate_tfm(char *digest, u16 alg_id,
 		/* now accumulate with current aggregate */
 		rc = crypto_shash_update(shash, d.digest,
 					 crypto_shash_digestsize(tfm));
+		if (rc != 0)
+			return rc;
 	}
 	if (!rc)
 		crypto_shash_final(shash, digest);
-- 
2.17.1