[PATCH 4.13 031/109] crypto: scompress - dont sleep with preemption disabled

Greg Kroah-Hartman
2017-09-24T20:53:14Z

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;
}