Patch "crypto: caam - fix endless loop when DECO acquire fails" has been added to the 4.9-stable tree

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    crypto: caam - fix endless loop when DECO acquire fails

to the 4.9-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     crypto-caam-fix-endless-loop-when-deco-acquire-fails.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 225ece3e7dad4cfc44cca38ce7a3a80f255ea8f1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Horia=20Geant=C4=83?= <horia.geanta@nxp.com>
Date: Mon, 5 Feb 2018 11:15:52 +0200
Subject: crypto: caam - fix endless loop when DECO acquire fails
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

From: Horia Geantă <horia.geanta@nxp.com>

commit 225ece3e7dad4cfc44cca38ce7a3a80f255ea8f1 upstream.

In case DECO0 cannot be acquired - i.e. run_descriptor_deco0() fails
with -ENODEV, caam_probe() enters an endless loop:

run_descriptor_deco0
	ret -ENODEV
	-> instantiate_rng
		-ENODEV, overwritten by -EAGAIN
		ret -EAGAIN
		-> caam_probe
			-EAGAIN results in endless loop

It turns out the error path in instantiate_rng() is incorrect,
the checks are done in the wrong order.

Fixes: 1005bccd7a4a6 ("crypto: caam - enable instantiation of all RNG4 state handles")
Reported-by: Bryan O'Donoghue <pure.logic@nexus-software.ie>
Suggested-by: Auer Lukas <lukas.auer@aisec.fraunhofer.de>
Signed-off-by: Horia Geantă <horia.geanta@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/crypto/caam/ctrl.c |    8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

--- a/drivers/crypto/caam/ctrl.c
+++ b/drivers/crypto/caam/ctrl.c
@@ -228,12 +228,16 @@ static int instantiate_rng(struct device
 		 * without any error (HW optimizations for later
 		 * CAAM eras), then try again.
 		 */
+		if (ret)
+			break;
+
 		rdsta_val = rd_reg32(&ctrl->r4tst[0].rdsta) & RDSTA_IFMASK;
 		if ((status && status != JRSTA_SSRC_JUMP_HALT_CC) ||
-		    !(rdsta_val & (1 << sh_idx)))
+		    !(rdsta_val & (1 << sh_idx))) {
 			ret = -EAGAIN;
-		if (ret)
 			break;
+		}
+
 		dev_info(ctrldev, "Instantiated RNG4 SH%d\n", sh_idx);
 		/* Clear the contents before recreating the descriptor */
 		memset(desc, 0x00, CAAM_CMD_SZ * 7);


Patches currently in stable-queue which might be from horia.geanta@nxp.com are

queue-4.9/crypto-caam-fix-endless-loop-when-deco-acquire-fails.patch