[PATCH v2 01/12] ima: Don't ignore errors from crypto_shash_update()

From: Roberto Sassu
Date: Fri Sep 04 2020 - 05:27:26 EST


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@xxxxxxxxxxxxxxx
Fixes: 3323eec921efd ("integrity: IMA as an integrity service provider")
Signed-off-by: Roberto Sassu <roberto.sassu@xxxxxxxxxx>
Reviewed-by: Mimi Zohar <zohar@xxxxxxxxxxxxx>
---
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 011c3c76af86..21989fa0c107 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;
}
/*
* Extend cumulative digest over TPM registers 8-9, which contain
--
2.27.GIT