Patch "crypto: caam - fix gfp allocation flags (part I)" has been added to the 4.12-stable tree

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

crypto: caam - fix gfp allocation flags (part I)

to the 4.12-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-gfp-allocation-flags-part-i.patch
and it can be found in the queue-4.12 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: =?UTF-8?q?Horia=20Geant=C4=83?= <[email protected]>
Date: Mon, 19 Jun 2017 11:44:45 +0300
Subject: crypto: caam - fix gfp allocation flags (part I)
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From: Horia Geantă <[email protected]>

commit 42cfcafb91dabb0f9d9e08396c39824535948c67 upstream.

Changes in the SW cts (ciphertext stealing) code in commit 0605c41cc53ca ("crypto: cts - Convert to skcipher") revealed a problem in the CAAM driver:
when cts(cbc(aes)) is executed and cts runs in SW, cbc(aes) is offloaded in CAAM; cts encrypts the last block in atomic context and CAAM incorrectly decides to use GFP_KERNEL for memory allocation.

Fix this by allowing GFP_KERNEL (sleeping) only when MAY_SLEEP flag is set, i.e. remove MAY_BACKLOG flag.

We split the fix in two parts - first is sent to -stable, while the second is not (since there is no known failure case).

---
 drivers/crypto/caam/caamalg.c |    3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

@@ -1475,8 +1475,7 @@ static struct ablkcipher_edesc *ablkciph
 	struct crypto_ablkcipher *ablkcipher = crypto_ablkcipher_reqtfm(req);
 	struct caam_ctx *ctx = crypto_ablkcipher_ctx(ablkcipher);
 	struct device *jrdev = ctx->jrdev;
-	gfp_t flags = (req->base.flags & (CRYPTO_TFM_REQ_MAY_BACKLOG |
-					  CRYPTO_TFM_REQ_MAY_SLEEP)) ?
+	gfp_t flags = (req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP) ?
 		       GFP_KERNEL : GFP_ATOMIC;
 	int src_nents, mapped_src_nents, dst_nents = 0, mapped_dst_nents = 0;
 	struct ablkcipher_edesc *edesc;

Patches currently in stable-queue which might be from [email protected] are

queue-4.12/crypto-caam-fix-gfp-allocation-flags-part-i.patch