Forwarded: [PATCH v1] Testing for a slub out of bounds and uaf

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Subject: [PATCH v1] Testing for a slub out of bounds and uaf
Author: nsvatoslav515@gmail.com

#syz test

Signed-off-by: Svyatoslav Nikolenko <nsvatoslav515@gmail.com>
---
 fs/ecryptfs/keystore.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/fs/ecryptfs/keystore.c b/fs/ecryptfs/keystore.c
index 51651314b7a6..256b7e317ea8 100644
--- a/fs/ecryptfs/keystore.c
+++ b/fs/ecryptfs/keystore.c
@@ -738,6 +738,20 @@ ecryptfs_write_tag_70_packet(char *dest, size_t *remaining_bytes,
 		goto out_free_unlock;
 	}
 
+	struct user_key_payload *ukp = user_key_payload_locked(auth_tok_key);
+		if (!ukp || ukp->datalen < sizeof(struct ecryptfs_auth_tok)) {
+			printk(KERN_ERR "Error key payload too small\n");
+			rc = -EINVAL;
+			goto out_free_unlock;
+		}
+
+	if (s->auth_tok->token.password.session_key_encryption_key_bytes >
+			sizeof(s->auth_tok->token.password.session_key_encryption_key)) {
+		printk(KERN_ERR "Error FNEK key size too large\n");
+		rc = -EINVAL;
+		goto out_free_unlock;
+	}
+
 	md5(s->auth_tok->token.password.session_key_encryption_key,
 	    s->auth_tok->token.password.session_key_encryption_key_bytes,
 	    s->hash);
-- 
2.47.3