Patch "crypto: scompress - don't sleep with preemption disabled" has been added to the 4.13-stable tree

Patch "crypto: scompress - don't sleep with preemption disabled" has been added to the 4.13-stable tree

[gregkh]

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

    crypto: scompress - don't sleep with preemption disabled

to the 4.13-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-scompress-don-t-sleep-with-preemption-disabled.patch
and it can be found in the queue-4.13 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 3c08377262880afc1621ab9cb6dbe7df47a6033d Mon Sep 17 00:00:00 2001
From: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Date: Fri, 21 Jul 2017 16:42:36 +0100
Subject: crypto: scompress - don't sleep with preemption disabled

From: Ard Biesheuvel <ard.biesheuvel@linaro.org>

commit 3c08377262880afc1621ab9cb6dbe7df47a6033d upstream.

Due to the use of per-CPU buffers, scomp_acomp_comp_decomp() executes
with preemption disabled, and so whether the CRYPTO_TFM_REQ_MAY_SLEEP
flag is set is irrelevant, since we cannot sleep anyway. So disregard
the flag, and use GFP_ATOMIC unconditionally.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 crypto/scompress.c |    4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

--- a/crypto/scompress.c
+++ b/crypto/scompress.c
@@ -211,9 +211,7 @@ static int scomp_acomp_comp_decomp(struc
 					      scratch_dst, &req->dlen, *ctx);
 	if (!ret) {
 		if (!req->dst) {
-			req->dst = crypto_scomp_sg_alloc(req->dlen,
-				   req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP ?
-				   GFP_KERNEL : GFP_ATOMIC);
+			req->dst = crypto_scomp_sg_alloc(req->dlen, GFP_ATOMIC);
 			if (!req->dst)
 				goto out;
 		}


Patches currently in stable-queue which might be from ard.biesheuvel@linaro.org are

queue-4.13/crypto-scompress-don-t-sleep-with-preemption-disabled.patch