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

commit 42cfcafb91 upstream.

Changes in the SW cts (ciphertext stealing) code in
commit 0605c41cc5 ("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).

Link: http://lkml.kernel.org/g/20170602122446.2427-1-david@sigma-star.at
Reported-by: David Gstir <david@sigma-star.at>
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>
This commit is contained in:
Horia Geantă 2017-06-19 11:44:45 +03:00 committed by Greg Kroah-Hartman
parent 090661e407
commit 0d6758f74a

View file

@ -2601,8 +2601,7 @@ static struct ablkcipher_edesc *ablkcipher_edesc_alloc(struct ablkcipher_request
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, dst_nents = 0, sec4_sg_bytes;
struct ablkcipher_edesc *edesc;