2018-01-25 09:54:12

by Jia-Ju Bai

Subject: [PATCH] crypto: rsa-pkcs1pad: Replace GFP_ATOMIC with GFP_KERNEL in pkcs1pad_encrypt_sign_complete

After checking all possible call chains to kzalloc here,
my tool finds that this kzalloc is never called in atomic context.
Thus GFP_ATOMIC is not necessary, and it can be replaced with GFP_KERNEL.

This is found by a static analysis tool named DCNS written by myself.

Signed-off-by: Jia-Ju Bai <[email protected]>
---
crypto/rsa-pkcs1pad.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/crypto/rsa-pkcs1pad.c b/crypto/rsa-pkcs1pad.c
index 2908f93..9893dbf 100644
--- a/crypto/rsa-pkcs1pad.c
+++ b/crypto/rsa-pkcs1pad.c
@@ -192,7 +192,7 @@ static int pkcs1pad_encrypt_sign_complete(struct akcipher_request *req, int err)
if (likely(!pad_len))
goto out;

- out_buf = kzalloc(ctx->key_size, GFP_ATOMIC);
+ out_buf = kzalloc(ctx->key_size, GFP_KERNEL);
err = -ENOMEM;
if (!out_buf)
goto out;
--
1.7.9.5

2018-02-16 01:11:39

by Herbert Xu

Subject: Re: [PATCH] crypto: rsa-pkcs1pad: Replace GFP_ATOMIC with GFP_KERNEL in pkcs1pad_encrypt_sign_complete

On Thu, Jan 25, 2018 at 05:57:54PM +0800, Jia-Ju Bai wrote:
> After checking all possible call chains to kzalloc here,
> my tool finds that this kzalloc is never called in atomic context.
> Thus GFP_ATOMIC is not necessary, and it can be replaced with GFP_KERNEL.
>
> This is found by a static analysis tool named DCNS written by myself.
>
> Signed-off-by: Jia-Ju Bai <[email protected]>

Patch applied. Thanks.
--
Email: Herbert Xu <[email protected]>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt