Commit 23c19e2c authored Aug 15, 2014 by Dmitry Kasatkin Committed by Mimi Zohar Sep 02, 2014

ima: prevent buffer overflow in ima_alloc_tfm()

This patch fixes the case where the file's signature/hash xattr contains
an invalid hash algorithm. Although we can not verify the xattr, we still
need to measure the file. Use the default IMA hash algorithm.

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

parent 9a8d289f

security/integrity/ima/ima_crypto.c

+4 −1

Original line number	Diff line number	Diff line
		@@ -116,7 +116,10 @@ static struct crypto_shash *ima_alloc_tfm(enum hash_algo algo)
		struct crypto_shash *tfm = ima_shash_tfm;
		int rc;

		if (algo != ima_hash_algo && algo < HASH_ALGO__LAST) {
		if (algo < 0 \|\| algo >= HASH_ALGO__LAST)
		algo = ima_hash_algo;

		if (algo != ima_hash_algo) {
		tfm = crypto_alloc_shash(hash_algo_name[algo], 0, 0);
		if (IS_ERR(tfm)) {
		rc = PTR_ERR(tfm);