If crypto_get_default_rng returns an error, the
function ecc_gen_privkey should return an error.
Instead, it currently tries to use the default_rng
nevertheless, thus creating a kernel panic with a
NULL pointer dereference.
Returning the error directly, as was supposedly
intended when looking at the code, fixes this.
Signed-off-by: Pierre Ducroquet <[email protected]>
---
crypto/ecc.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/crypto/ecc.c b/crypto/ecc.c
index 633a9bcdc574..18f32f2a5e1c 100644
--- a/crypto/ecc.c
+++ b/crypto/ecc.c
@@ -964,7 +964,7 @@ int ecc_gen_privkey(unsigned int curve_id, unsigned int ndigits, u64 *privkey)
* DRBG with a security strength of 256.
*/
if (crypto_get_default_rng())
- err = -EFAULT;
+ return -EFAULT;
err = crypto_rng_get_bytes(crypto_default_rng, (u8 *)priv, nbytes);
crypto_put_default_rng();
--
2.15.0
Hi Pierre,
On 12 November 2017 at 19:54, Pierre Ducroquet <[email protected]> wrote:
> If crypto_get_default_rng returns an error, the
> function ecc_gen_privkey should return an error.
> Instead, it currently tries to use the default_rng
> nevertheless, thus creating a kernel panic with a
> NULL pointer dereference.
> Returning the error directly, as was supposedly
> intended when looking at the code, fixes this.
>
> Signed-off-by: Pierre Ducroquet <[email protected]>
> ---
> crypto/ecc.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/crypto/ecc.c b/crypto/ecc.c
> index 633a9bcdc574..18f32f2a5e1c 100644
> --- a/crypto/ecc.c
> +++ b/crypto/ecc.c
> @@ -964,7 +964,7 @@ int ecc_gen_privkey(unsigned int curve_id, unsigned int ndigits, u64 *privkey)
> * DRBG with a security strength of 256.
> */
> if (crypto_get_default_rng())
> - err = -EFAULT;
> + return -EFAULT;
>
> err = crypto_rng_get_bytes(crypto_default_rng, (u8 *)priv, nbytes);
> crypto_put_default_rng();
> --
> 2.15.0
>
Looks good to me.
Reviewed-by: PrasannaKumar Muralidharan <[email protected]>
Regards,
PrasannaKumar
On Sunday, November 12, 2017 8:16:27 PM CET PrasannaKumar Muralidharan wrote:
> Hi Pierre,
>
> On 12 November 2017 at 19:54, Pierre Ducroquet <[email protected]> wrote:
> > If crypto_get_default_rng returns an error, the
> > function ecc_gen_privkey should return an error.
> > Instead, it currently tries to use the default_rng
> > nevertheless, thus creating a kernel panic with a
> > NULL pointer dereference.
> > Returning the error directly, as was supposedly
> > intended when looking at the code, fixes this.
> >
> > Signed-off-by: Pierre Ducroquet <[email protected]>
> > ---
> >
> > crypto/ecc.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/crypto/ecc.c b/crypto/ecc.c
> > index 633a9bcdc574..18f32f2a5e1c 100644
> > --- a/crypto/ecc.c
> > +++ b/crypto/ecc.c
> > @@ -964,7 +964,7 @@ int ecc_gen_privkey(unsigned int curve_id, unsigned
> > int ndigits, u64 *privkey)>
> > * DRBG with a security strength of 256.
> > */
> >
> > if (crypto_get_default_rng())
> >
> > - err = -EFAULT;
> > + return -EFAULT;
> >
> > err = crypto_rng_get_bytes(crypto_default_rng, (u8 *)priv,
> > nbytes);
> > crypto_put_default_rng();
> >
> > --
> > 2.15.0
>
> Looks good to me.
>
> Reviewed-by: PrasannaKumar Muralidharan <[email protected]>
>
> Regards,
> PrasannaKumar
Hi
Thanks for your review.
Is there anything I should do to have this merged ? It fixes a kernel panic at
boot on my computer, so I suppose other people may have that too.
Regards
Pierre
On Sun, Nov 12, 2017 at 03:24:32PM +0100, Pierre Ducroquet wrote:
> If crypto_get_default_rng returns an error, the
> function ecc_gen_privkey should return an error.
> Instead, it currently tries to use the default_rng
> nevertheless, thus creating a kernel panic with a
> NULL pointer dereference.
> Returning the error directly, as was supposedly
> intended when looking at the code, fixes this.
>
> Signed-off-by: Pierre Ducroquet <[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
On Wednesday, November 29, 2017 5:34:30 PM CET you wrote:
> On Sun, Nov 12, 2017 at 03:24:32PM +0100, Pierre Ducroquet wrote:
> > If crypto_get_default_rng returns an error, the
> > function ecc_gen_privkey should return an error.
> > Instead, it currently tries to use the default_rng
> > nevertheless, thus creating a kernel panic with a
> > NULL pointer dereference.
> > Returning the error directly, as was supposedly
> > intended when looking at the code, fixes this.
> >
> > Signed-off-by: Pierre Ducroquet <[email protected]>
>
> Patch applied. Thanks.
Thanks to you.
Will it be backported to 4.14 and the LTS releases ? Currently, no recent
debian kernel can boot on my system without that patch (I don't know why
nobody else noticed that before).
Pierre
On Wednesday, November 29, 2017 5:34:30 PM CET Herbert Xu wrote:
> On Sun, Nov 12, 2017 at 03:24:32PM +0100, Pierre Ducroquet wrote:
> > If crypto_get_default_rng returns an error, the
> > function ecc_gen_privkey should return an error.
> > Instead, it currently tries to use the default_rng
> > nevertheless, thus creating a kernel panic with a
> > NULL pointer dereference.
> > Returning the error directly, as was supposedly
> > intended when looking at the code, fixes this.
> >
> > Signed-off-by: Pierre Ducroquet <[email protected]>
>
> Patch applied. Thanks.
Hi
How long will it take for the patch to be merged in an official release ?
This simple patch fixes a kernel panic at boot, it would be great for it to be
merged in 4.15.
Thanks
Pierre