crypto: rsa-pkcs1pad - fix buffer overread in pkcs1pad_verify_complete()

commit a24611e upstream. Before checking whether the expected digest_info is present, we need to check that there are enough bytes remaining. Fixes: a49de37 ("crypto: Add hash param to pkcs1pad") Cc: <[email protected]> # v4.6+ Cc: Tadeusz Struk <[email protected]> Signed-off-by: Eric Biggers <[email protected]> Signed-off-by: Herbert Xu <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]>
ammarfaizi2 · Apr 7, 2022 · e997e9e · e997e9e
1 parent c2e1525
commit e997e9e
Showing 1 changed file with 2 additions and 0 deletions.
diff --git a/crypto/rsa-pkcs1pad.c b/crypto/rsa-pkcs1pad.c
@@ -476,6 +476,8 @@ static int pkcs1pad_verify_complete(struct akcipher_request *req, int err)
 	pos++;
 
 	if (digest_info) {
+		if (digest_info->size > dst_len - pos)
+			goto done;
 		if (crypto_memneq(out_buf + pos, digest_info->data,
 				  digest_info->size))
 			goto done;