Merge tag 's390-7.2-3' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linuxHEADmaster

Pull s390 fixes from Vasily Gorbik:

 - Fix PKEY_VERIFYPROTK ioctl key type handling by removing the generic
   key-length based type check with its wrong bit-size calculation, and
   leaving protected key verification to the pkey handler

 - Fix monwriter buffer reuse by rejecting records that change the data
   length, preventing out of bounds user copy into the kernel buffer

* tag 's390-7.2-3' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/monwriter: Reject buffer reuse with different data length
  pkey: Move keytype check from pkey api to handler

2 files changed, 4 insertions, 10 deletions

diff --git a/drivers/s390/char/monwriter.c b/drivers/s390/char/monwriter.c
index eaeb4a6384d1..ecf121a87f88 100644
--- a/drivers/s390/char/monwriter.c
+++ b/drivers/s390/char/monwriter.c
@@ -122,6 +122,9 @@ static int monwrite_new_hdr(struct mon_private *monpriv)
 			kfree(monbuf->data);
 			kfree(monbuf);
 			monbuf = NULL;
+		} else if (monbuf->hdr.datalen != monhdr->datalen) {
+			/* Data with buffer reuse must not change its length */
+			return -EINVAL;
 		}
 	} else if (monhdr->mon_function != MONWRITE_STOP_INTERVAL) {
 		if (mon_buf_count >= mon_max_bufs)
diff --git a/drivers/s390/crypto/pkey_api.c b/drivers/s390/crypto/pkey_api.c
index 28e1007005f2..5d8f63f390a8 100644
--- a/drivers/s390/crypto/pkey_api.c
+++ b/drivers/s390/crypto/pkey_api.c
@@ -327,7 +327,6 @@ static int pkey_ioctl_verifyprotk(struct pkey_verifyprotk __user *uvp)
 {
 	struct pkey_verifyprotk kvp;
 	struct protaeskeytoken *t;
-	u32 keytype;
 	u8 *tmpbuf;
 	int rc;
 
@@ -341,14 +340,6 @@ static int pkey_ioctl_verifyprotk(struct pkey_verifyprotk __user *uvp)
 		return -EINVAL;
 	}
 
-	keytype = pkey_aes_bitsize_to_keytype(8 * kvp.protkey.len);
-	if (!keytype) {
-		PKEY_DBF_ERR("%s unknown/unsupported protkey length %u\n",
-			     __func__, kvp.protkey.len);
-		memzero_explicit(&kvp, sizeof(kvp));
-		return -EINVAL;
-	}
-
 	/* build a 'protected key token' from the raw protected key */
 	tmpbuf = kzalloc(sizeof(*t), GFP_KERNEL);
 	if (!tmpbuf) {
@@ -358,7 +349,7 @@ static int pkey_ioctl_verifyprotk(struct pkey_verifyprotk __user *uvp)
 	t = (struct protaeskeytoken *)tmpbuf;
 	t->type = TOKTYPE_NON_CCA;
 	t->version = TOKVER_PROTECTED_KEY;
-	t->keytype = keytype;
+	t->keytype = kvp.protkey.type;
 	t->len = kvp.protkey.len;
 	memcpy(t->protkey, kvp.protkey.protkey, kvp.protkey.len);