[PATCH v5 0/2] KEYS: asymmetric: Copy sig and digest in public_key_verify_signature()

[PATCH v5 0/2] KEYS: asymmetric: Copy sig and digest in public_key_verify_signature()

[Roberto Sassu]

From: Roberto Sassu <roberto.sassu@huawei.com>

Changelog:

v4:
 - Replace sg_init_table()/sg_set_buf() with sg_init_one() (suggested by
   Eric)

v3:

v2:
 - Add patch by Herbert to take only the needed bytes for a MPI from the
   scatterlist
 - Use only one scatterlist for signature and digest (suggested by Eric)
 - Rename key variable to buf (suggested by Eric)
 - Rename key_max_len variable to buf_len
 - Use size_t for the buf_len variable instead of u32

v1:
 - Unconditionally copy the signature and digest to the buffer to keep the
   code simple (suggested by Eric)

Herbert Xu (1):
  lib/mpi: Fix buffer overrun when SG is too long

Roberto Sassu (1):
  KEYS: asymmetric: Copy sig and digest in public_key_verify_signature()

 crypto/asymmetric_keys/public_key.c | 38 ++++++++++++++++-------------
 lib/mpi/mpicoder.c                  |  3 ++-
 2 files changed, 23 insertions(+), 18 deletions(-)

-- 
2.25.1

[PATCH v5 1/2] lib/mpi: Fix buffer overrun when SG is too long

[Roberto Sassu]

From: Herbert Xu <herbert@gondor.apana.org.au>

The helper mpi_read_raw_from_sgl sets the number of entries in
the SG list according to nbytes.  However, if the last entry
in the SG list contains more data than nbytes, then it may overrun
the buffer because it only allocates enough memory for nbytes.

Fixes: 2d4d1eea540b ("lib/mpi: Add mpi sgl helpers")
Reported-by: Roberto Sassu <roberto.sassu@huaweicloud.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
---
 lib/mpi/mpicoder.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/mpi/mpicoder.c b/lib/mpi/mpicoder.c
index 39c4c6731094..3cb6bd148fa9 100644
--- a/lib/mpi/mpicoder.c
+++ b/lib/mpi/mpicoder.c
@@ -504,7 +504,8 @@ MPI mpi_read_raw_from_sgl(struct scatterlist *sgl, unsigned int nbytes)
 
 	while (sg_miter_next(&miter)) {
 		buff = miter.addr;
-		len = miter.length;
+		len = min_t(unsigned, miter.length, nbytes);
+		nbytes -= len;
 
 		for (x = 0; x < len; x++) {
 			a <<= 8;
-- 
2.25.1

Re: [PATCH v5 1/2] lib/mpi: Fix buffer overrun when SG is too long

[Eric Biggers]

On Tue, Dec 27, 2022 at 03:27:39PM +0100, Roberto Sassu wrote:
> From: Herbert Xu <herbert@gondor.apana.org.au>
> 
> The helper mpi_read_raw_from_sgl sets the number of entries in
> the SG list according to nbytes.  However, if the last entry
> in the SG list contains more data than nbytes, then it may overrun
> the buffer because it only allocates enough memory for nbytes.
> 
> Fixes: 2d4d1eea540b ("lib/mpi: Add mpi sgl helpers")
> Reported-by: Roberto Sassu <roberto.sassu@huaweicloud.com>
> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
> ---
>  lib/mpi/mpicoder.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)

Reviewed-by: Eric Biggers <ebiggers@google.com>

- Eric

RE: [PATCH v5 1/2] lib/mpi: Fix buffer overrun when SG is too long

[David Laight]

From: Roberto Sassu
> Sent: 27 December 2022 14:28
> 
> From: Herbert Xu <herbert@gondor.apana.org.au>
> 
> The helper mpi_read_raw_from_sgl sets the number of entries in
> the SG list according to nbytes.  However, if the last entry
> in the SG list contains more data than nbytes, then it may overrun
> the buffer because it only allocates enough memory for nbytes.
> 
> Fixes: 2d4d1eea540b ("lib/mpi: Add mpi sgl helpers")
> Reported-by: Roberto Sassu <roberto.sassu@huaweicloud.com>
> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
> ---
>  lib/mpi/mpicoder.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/lib/mpi/mpicoder.c b/lib/mpi/mpicoder.c
> index 39c4c6731094..3cb6bd148fa9 100644
> --- a/lib/mpi/mpicoder.c
> +++ b/lib/mpi/mpicoder.c
> @@ -504,7 +504,8 @@ MPI mpi_read_raw_from_sgl(struct scatterlist *sgl, unsigned int nbytes)
> 
>  	while (sg_miter_next(&miter)) {
>  		buff = miter.addr;
> -		len = miter.length;
> +		len = min_t(unsigned, miter.length, nbytes);

Technically that min_t() is incorrect.
miter.length is size_t (unsigned long on 64bit) and nbytes unsigned int.
Any cast needs to force the smaller type to the larger one.
(Clearly here the domain of the values is probably than 4G - but that isn't
the point. There must be some places where the sg length needs to
be size_t because 32 bits isn't enough.)

In reality min() is being completely over-zealous in its checking and
should allow comparisons where the signed-ness of the two values matches.
Search for the patch I posted before xmas.

	David


> +		nbytes -= len;
> 
>  		for (x = 0; x < len; x++) {
>  			a <<= 8;
> --
> 2.25.1

-
Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK
Registration No: 1397386 (Wales)

Re: [PATCH v5 1/2] lib/mpi: Fix buffer overrun when SG is too long

[Herbert Xu]

On Fri, Dec 30, 2022 at 01:35:07PM +0000, David Laight wrote:
>
> miter.length is size_t (unsigned long on 64bit) and nbytes unsigned int.

miter.length is bounded by sg->length which is unsigned int.

Cheers,
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt

RE: [PATCH v5 1/2] lib/mpi: Fix buffer overrun when SG is too long

[David Laight]

From: Herbert Xu
> Sent: 30 December 2022 15:40
> 
> On Fri, Dec 30, 2022 at 01:35:07PM +0000, David Laight wrote:
> >
> > miter.length is size_t (unsigned long on 64bit) and nbytes unsigned int.
> 
> miter.length is bounded by sg->length which is unsigned int.

I did say 'technically' :-)

Should there be a sg_miter_stop() before the return at the bottom?
Care seems to have been taken to add one before an earlier error return.
(The logic in that function is very strange...)

Indeed other parts of the file are equally strange.
The big multi-line if-else in twocompl() is just:
	p[i] = (p[1] ^ 0xff) + 1;
or even:
	p[i] = -p[i];
That function could also return the 'zero status' to correct
for -0 (rather than the extra check earlier in the caller).

	David

-
Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK
Registration No: 1397386 (Wales)

Re: [PATCH v5 1/2] lib/mpi: Fix buffer overrun when SG is too long

[Herbert Xu]

On Tue, Dec 27, 2022 at 03:27:39PM +0100, Roberto Sassu wrote:
> From: Herbert Xu <herbert@gondor.apana.org.au>
> 
> The helper mpi_read_raw_from_sgl sets the number of entries in
> the SG list according to nbytes.  However, if the last entry
> in the SG list contains more data than nbytes, then it may overrun
> the buffer because it only allocates enough memory for nbytes.
> 
> Fixes: 2d4d1eea540b ("lib/mpi: Add mpi sgl helpers")
> Reported-by: Roberto Sassu <roberto.sassu@huaweicloud.com>
> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
> ---
>  lib/mpi/mpicoder.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)

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

Re: [PATCH v5 1/2] lib/mpi: Fix buffer overrun when SG is too long

[Roberto Sassu]

On Fri, 2023-01-06 at 23:18 +0800, Herbert Xu wrote:
> On Tue, Dec 27, 2022 at 03:27:39PM +0100, Roberto Sassu wrote:
> > From: Herbert Xu <herbert@gondor.apana.org.au>
> > 
> > The helper mpi_read_raw_from_sgl sets the number of entries in
> > the SG list according to nbytes.  However, if the last entry
> > in the SG list contains more data than nbytes, then it may overrun
> > the buffer because it only allocates enough memory for nbytes.
> > 
> > Fixes: 2d4d1eea540b ("lib/mpi: Add mpi sgl helpers")
> > Reported-by: Roberto Sassu <roberto.sassu@huaweicloud.com>
> > Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
> > ---
> >  lib/mpi/mpicoder.c | 3 ++-
> >  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> Patch applied.  Thanks.

Hi Herbert

will you take also the second patch?

Thanks

Roberto

Re: [PATCH v5 1/2] lib/mpi: Fix buffer overrun when SG is too long

[Herbert Xu]

On Mon, Jan 16, 2023 at 09:57:57AM +0100, Roberto Sassu wrote:
>
> Hi Herbert
> 
> will you take also the second patch?

That's part of David Howells' tree so hopefully he will pick
it up soon.

Thanks,
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt

Re: [PATCH v5 1/2] lib/mpi: Fix buffer overrun when SG is too long

[Roberto Sassu]

On 1/16/2023 10:06 AM, Herbert Xu wrote:
> On Mon, Jan 16, 2023 at 09:57:57AM +0100, Roberto Sassu wrote:
>>
>> Hi Herbert
>>
>> will you take also the second patch?
> 
> That's part of David Howells' tree so hopefully he will pick
> it up soon.

Hi David

could you please take the second patch?

Thanks

Roberto

[PATCH v5 2/2] KEYS: asymmetric: Copy sig and digest in public_key_verify_signature()

[Roberto Sassu]

From: Roberto Sassu <roberto.sassu@huawei.com>

Commit ac4e97abce9b8 ("scatterlist: sg_set_buf() argument must be in linear
mapping") checks that both the signature and the digest reside in the
linear mapping area.

However, more recently commit ba14a194a434c ("fork: Add generic vmalloced
stack support") made it possible to move the stack in the vmalloc area,
which is not contiguous, and thus not suitable for sg_set_buf() which needs
adjacent pages.

Always make a copy of the signature and digest in the same buffer used to
store the key and its parameters, and pass them to sg_init_one(). Prefer it
to conditionally doing the copy if necessary, to keep the code simple. The
buffer allocated with kmalloc() is in the linear mapping area.

Cc: stable@vger.kernel.org # 4.9.x
Fixes: ba14a194a434 ("fork: Add generic vmalloced stack support")
Link: https://lore.kernel.org/linux-integrity/Y4pIpxbjBdajymBJ@sol.localdomain/
Suggested-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
---
 crypto/asymmetric_keys/public_key.c | 38 ++++++++++++++++-------------
 1 file changed, 21 insertions(+), 17 deletions(-)

diff --git a/crypto/asymmetric_keys/public_key.c b/crypto/asymmetric_keys/public_key.c
index 2f8352e88860..49a3f7c01149 100644
--- a/crypto/asymmetric_keys/public_key.c
+++ b/crypto/asymmetric_keys/public_key.c
@@ -360,9 +360,10 @@ int public_key_verify_signature(const struct public_key *pkey,
 	struct crypto_wait cwait;
 	struct crypto_akcipher *tfm;
 	struct akcipher_request *req;
-	struct scatterlist src_sg[2];
+	struct scatterlist src_sg;
 	char alg_name[CRYPTO_MAX_ALG_NAME];
-	char *key, *ptr;
+	char *buf, *ptr;
+	size_t buf_len;
 	int ret;
 
 	pr_devel("==>%s()\n", __func__);
@@ -400,34 +401,37 @@ int public_key_verify_signature(const struct public_key *pkey,
 	if (!req)
 		goto error_free_tfm;
 
-	key = kmalloc(pkey->keylen + sizeof(u32) * 2 + pkey->paramlen,
-		      GFP_KERNEL);
-	if (!key)
+	buf_len = max_t(size_t, pkey->keylen + sizeof(u32) * 2 + pkey->paramlen,
+			sig->s_size + sig->digest_size);
+
+	buf = kmalloc(buf_len, GFP_KERNEL);
+	if (!buf)
 		goto error_free_req;
 
-	memcpy(key, pkey->key, pkey->keylen);
-	ptr = key + pkey->keylen;
+	memcpy(buf, pkey->key, pkey->keylen);
+	ptr = buf + pkey->keylen;
 	ptr = pkey_pack_u32(ptr, pkey->algo);
 	ptr = pkey_pack_u32(ptr, pkey->paramlen);
 	memcpy(ptr, pkey->params, pkey->paramlen);
 
 	if (pkey->key_is_private)
-		ret = crypto_akcipher_set_priv_key(tfm, key, pkey->keylen);
+		ret = crypto_akcipher_set_priv_key(tfm, buf, pkey->keylen);
 	else
-		ret = crypto_akcipher_set_pub_key(tfm, key, pkey->keylen);
+		ret = crypto_akcipher_set_pub_key(tfm, buf, pkey->keylen);
 	if (ret)
-		goto error_free_key;
+		goto error_free_buf;
 
 	if (strcmp(pkey->pkey_algo, "sm2") == 0 && sig->data_size) {
 		ret = cert_sig_digest_update(sig, tfm);
 		if (ret)
-			goto error_free_key;
+			goto error_free_buf;
 	}
 
-	sg_init_table(src_sg, 2);
-	sg_set_buf(&src_sg[0], sig->s, sig->s_size);
-	sg_set_buf(&src_sg[1], sig->digest, sig->digest_size);
-	akcipher_request_set_crypt(req, src_sg, NULL, sig->s_size,
+	memcpy(buf, sig->s, sig->s_size);
+	memcpy(buf + sig->s_size, sig->digest, sig->digest_size);
+
+	sg_init_one(&src_sg, buf, sig->s_size + sig->digest_size);
+	akcipher_request_set_crypt(req, &src_sg, NULL, sig->s_size,
 				   sig->digest_size);
 	crypto_init_wait(&cwait);
 	akcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG |
@@ -435,8 +439,8 @@ int public_key_verify_signature(const struct public_key *pkey,
 				      crypto_req_done, &cwait);
 	ret = crypto_wait_req(crypto_akcipher_verify(req), &cwait);
 
-error_free_key:
-	kfree(key);
+error_free_buf:
+	kfree(buf);
 error_free_req:
 	akcipher_request_free(req);
 error_free_tfm:
-- 
2.25.1

Re: [PATCH v5 2/2] KEYS: asymmetric: Copy sig and digest in public_key_verify_signature()

[Eric Biggers]

On Tue, Dec 27, 2022 at 03:27:40PM +0100, Roberto Sassu wrote:
> From: Roberto Sassu <roberto.sassu@huawei.com>
> 
> Commit ac4e97abce9b8 ("scatterlist: sg_set_buf() argument must be in linear
> mapping") checks that both the signature and the digest reside in the
> linear mapping area.
> 
> However, more recently commit ba14a194a434c ("fork: Add generic vmalloced
> stack support") made it possible to move the stack in the vmalloc area,
> which is not contiguous, and thus not suitable for sg_set_buf() which needs
> adjacent pages.
> 
> Always make a copy of the signature and digest in the same buffer used to
> store the key and its parameters, and pass them to sg_init_one(). Prefer it
> to conditionally doing the copy if necessary, to keep the code simple. The
> buffer allocated with kmalloc() is in the linear mapping area.
> 
> Cc: stable@vger.kernel.org # 4.9.x
> Fixes: ba14a194a434 ("fork: Add generic vmalloced stack support")
> Link: https://lore.kernel.org/linux-integrity/Y4pIpxbjBdajymBJ@sol.localdomain/
> Suggested-by: Eric Biggers <ebiggers@kernel.org>
> Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
> ---
>  crypto/asymmetric_keys/public_key.c | 38 ++++++++++++++++-------------
>  1 file changed, 21 insertions(+), 17 deletions(-)

Reviewed-by: Eric Biggers <ebiggers@google.com>

- Eric

Re: [PATCH v5 2/2] KEYS: asymmetric: Copy sig and digest in public_key_verify_signature()

[Roberto Sassu]

On Thu, 2022-12-29 at 14:39 -0800, Eric Biggers wrote:
> On Tue, Dec 27, 2022 at 03:27:40PM +0100, Roberto Sassu wrote:
> > From: Roberto Sassu <roberto.sassu@huawei.com>
> > 
> > Commit ac4e97abce9b8 ("scatterlist: sg_set_buf() argument must be in linear
> > mapping") checks that both the signature and the digest reside in the
> > linear mapping area.
> > 
> > However, more recently commit ba14a194a434c ("fork: Add generic vmalloced
> > stack support") made it possible to move the stack in the vmalloc area,
> > which is not contiguous, and thus not suitable for sg_set_buf() which needs
> > adjacent pages.
> > 
> > Always make a copy of the signature and digest in the same buffer used to
> > store the key and its parameters, and pass them to sg_init_one(). Prefer it
> > to conditionally doing the copy if necessary, to keep the code simple. The
> > buffer allocated with kmalloc() is in the linear mapping area.
> > 
> > Cc: stable@vger.kernel.org # 4.9.x
> > Fixes: ba14a194a434 ("fork: Add generic vmalloced stack support")
> > Link: https://lore.kernel.org/linux-integrity/Y4pIpxbjBdajymBJ@sol.localdomain/
> > Suggested-by: Eric Biggers <ebiggers@kernel.org>
> > Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
> > ---
> >  crypto/asymmetric_keys/public_key.c | 38 ++++++++++++++++-------------
> >  1 file changed, 21 insertions(+), 17 deletions(-)
> 
> Reviewed-by: Eric Biggers <ebiggers@google.com>

Hi David

could you please take this patch in your repo, if it is ok?

Thanks

Roberto

Re: [PATCH v5 2/2] KEYS: asymmetric: Copy sig and digest in public_key_verify_signature()

[Roberto Sassu]

On Fri, 2023-01-27 at 09:27 +0100, Roberto Sassu wrote:
> On Thu, 2022-12-29 at 14:39 -0800, Eric Biggers wrote:
> > On Tue, Dec 27, 2022 at 03:27:40PM +0100, Roberto Sassu wrote:
> > > From: Roberto Sassu <roberto.sassu@huawei.com>
> > > 
> > > Commit ac4e97abce9b8 ("scatterlist: sg_set_buf() argument must be in linear
> > > mapping") checks that both the signature and the digest reside in the
> > > linear mapping area.
> > > 
> > > However, more recently commit ba14a194a434c ("fork: Add generic vmalloced
> > > stack support") made it possible to move the stack in the vmalloc area,
> > > which is not contiguous, and thus not suitable for sg_set_buf() which needs
> > > adjacent pages.
> > > 
> > > Always make a copy of the signature and digest in the same buffer used to
> > > store the key and its parameters, and pass them to sg_init_one(). Prefer it
> > > to conditionally doing the copy if necessary, to keep the code simple. The
> > > buffer allocated with kmalloc() is in the linear mapping area.
> > > 
> > > Cc: stable@vger.kernel.org # 4.9.x
> > > Fixes: ba14a194a434 ("fork: Add generic vmalloced stack support")
> > > Link: https://lore.kernel.org/linux-integrity/Y4pIpxbjBdajymBJ@sol.localdomain/
> > > Suggested-by: Eric Biggers <ebiggers@kernel.org>
> > > Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
> > > ---
> > >  crypto/asymmetric_keys/public_key.c | 38 ++++++++++++++++-------------
> > >  1 file changed, 21 insertions(+), 17 deletions(-)
> > 
> > Reviewed-by: Eric Biggers <ebiggers@google.com>
> 
> Hi David
> 
> could you please take this patch in your repo, if it is ok?

Kindly ask your support here. Has this patch been queued somewhere?
Wasn't able to find it, also it is not in linux-next.

Thanks

Roberto

Re: [PATCH v5 2/2] KEYS: asymmetric: Copy sig and digest in public_key_verify_signature()

[Eric Biggers]

On Thu, Feb 09, 2023 at 11:49:19AM +0100, Roberto Sassu wrote:
> On Fri, 2023-01-27 at 09:27 +0100, Roberto Sassu wrote:
> > On Thu, 2022-12-29 at 14:39 -0800, Eric Biggers wrote:
> > > On Tue, Dec 27, 2022 at 03:27:40PM +0100, Roberto Sassu wrote:
> > > > From: Roberto Sassu <roberto.sassu@huawei.com>
> > > > 
> > > > Commit ac4e97abce9b8 ("scatterlist: sg_set_buf() argument must be in linear
> > > > mapping") checks that both the signature and the digest reside in the
> > > > linear mapping area.
> > > > 
> > > > However, more recently commit ba14a194a434c ("fork: Add generic vmalloced
> > > > stack support") made it possible to move the stack in the vmalloc area,
> > > > which is not contiguous, and thus not suitable for sg_set_buf() which needs
> > > > adjacent pages.
> > > > 
> > > > Always make a copy of the signature and digest in the same buffer used to
> > > > store the key and its parameters, and pass them to sg_init_one(). Prefer it
> > > > to conditionally doing the copy if necessary, to keep the code simple. The
> > > > buffer allocated with kmalloc() is in the linear mapping area.
> > > > 
> > > > Cc: stable@vger.kernel.org # 4.9.x
> > > > Fixes: ba14a194a434 ("fork: Add generic vmalloced stack support")
> > > > Link: https://lore.kernel.org/linux-integrity/Y4pIpxbjBdajymBJ@sol.localdomain/
> > > > Suggested-by: Eric Biggers <ebiggers@kernel.org>
> > > > Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
> > > > ---
> > > >  crypto/asymmetric_keys/public_key.c | 38 ++++++++++++++++-------------
> > > >  1 file changed, 21 insertions(+), 17 deletions(-)
> > > 
> > > Reviewed-by: Eric Biggers <ebiggers@google.com>
> > 
> > Hi David
> > 
> > could you please take this patch in your repo, if it is ok?
> 
> Kindly ask your support here. Has this patch been queued somewhere?
> Wasn't able to find it, also it is not in linux-next.
> 

The maintainer of asymmetric_keys (David Howells) is ignoring this patch, so
you'll need to find someone else to apply it.  Herbert Xu, the maintainer of the
crypto subsystem, might be willing to apply it.  Or maybe Jarkko Sakkinen, who
is a co-maintainer of the keyrings subsystem (but not asymmetric_keys, for some
reason; should that change?).

- Eric

Re: [PATCH v5 2/2] KEYS: asymmetric: Copy sig and digest in public_key_verify_signature()

[Paul Moore]

On Thu, Feb 9, 2023 at 1:53 PM Eric Biggers <ebiggers@kernel.org> wrote:
> On Thu, Feb 09, 2023 at 11:49:19AM +0100, Roberto Sassu wrote:
> > On Fri, 2023-01-27 at 09:27 +0100, Roberto Sassu wrote:
> > > On Thu, 2022-12-29 at 14:39 -0800, Eric Biggers wrote:
> > > > On Tue, Dec 27, 2022 at 03:27:40PM +0100, Roberto Sassu wrote:
> > > > > From: Roberto Sassu <roberto.sassu@huawei.com>
> > > > >
> > > > > Commit ac4e97abce9b8 ("scatterlist: sg_set_buf() argument must be in linear
> > > > > mapping") checks that both the signature and the digest reside in the
> > > > > linear mapping area.
> > > > >
> > > > > However, more recently commit ba14a194a434c ("fork: Add generic vmalloced
> > > > > stack support") made it possible to move the stack in the vmalloc area,
> > > > > which is not contiguous, and thus not suitable for sg_set_buf() which needs
> > > > > adjacent pages.
> > > > >
> > > > > Always make a copy of the signature and digest in the same buffer used to
> > > > > store the key and its parameters, and pass them to sg_init_one(). Prefer it
> > > > > to conditionally doing the copy if necessary, to keep the code simple. The
> > > > > buffer allocated with kmalloc() is in the linear mapping area.
> > > > >
> > > > > Cc: stable@vger.kernel.org # 4.9.x
> > > > > Fixes: ba14a194a434 ("fork: Add generic vmalloced stack support")
> > > > > Link: https://lore.kernel.org/linux-integrity/Y4pIpxbjBdajymBJ@sol.localdomain/
> > > > > Suggested-by: Eric Biggers <ebiggers@kernel.org>
> > > > > Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
> > > > > ---
> > > > >  crypto/asymmetric_keys/public_key.c | 38 ++++++++++++++++-------------
> > > > >  1 file changed, 21 insertions(+), 17 deletions(-)
> > > >
> > > > Reviewed-by: Eric Biggers <ebiggers@google.com>
> > >
> > > Hi David
> > >
> > > could you please take this patch in your repo, if it is ok?
> >
> > Kindly ask your support here. Has this patch been queued somewhere?
> > Wasn't able to find it, also it is not in linux-next.
> >
>
> The maintainer of asymmetric_keys (David Howells) is ignoring this patch, so
> you'll need to find someone else to apply it.  Herbert Xu, the maintainer of the
> crypto subsystem, might be willing to apply it.  Or maybe Jarkko Sakkinen, who
> is a co-maintainer of the keyrings subsystem (but not asymmetric_keys, for some
> reason; should that change?).

It is problematic that David isn't replying to this.  I have no idea
if it will work, but I just reached out to him to see if I can draw
his attention back to this ...

--
paul-moore.com

Re: [PATCH v5 2/2] KEYS: asymmetric: Copy sig and digest in public_key_verify_signature()

[Jarkko Sakkinen]

On Thu, Feb 09, 2023 at 05:46:32PM -0500, Paul Moore wrote:
> On Thu, Feb 9, 2023 at 1:53 PM Eric Biggers <ebiggers@kernel.org> wrote:
> > On Thu, Feb 09, 2023 at 11:49:19AM +0100, Roberto Sassu wrote:
> > > On Fri, 2023-01-27 at 09:27 +0100, Roberto Sassu wrote:
> > > > On Thu, 2022-12-29 at 14:39 -0800, Eric Biggers wrote:
> > > > > On Tue, Dec 27, 2022 at 03:27:40PM +0100, Roberto Sassu wrote:
> > > > > > From: Roberto Sassu <roberto.sassu@huawei.com>
> > > > > >
> > > > > > Commit ac4e97abce9b8 ("scatterlist: sg_set_buf() argument must be in linear
> > > > > > mapping") checks that both the signature and the digest reside in the
> > > > > > linear mapping area.
> > > > > >
> > > > > > However, more recently commit ba14a194a434c ("fork: Add generic vmalloced
> > > > > > stack support") made it possible to move the stack in the vmalloc area,
> > > > > > which is not contiguous, and thus not suitable for sg_set_buf() which needs
> > > > > > adjacent pages.
> > > > > >
> > > > > > Always make a copy of the signature and digest in the same buffer used to
> > > > > > store the key and its parameters, and pass them to sg_init_one(). Prefer it
> > > > > > to conditionally doing the copy if necessary, to keep the code simple. The
> > > > > > buffer allocated with kmalloc() is in the linear mapping area.
> > > > > >
> > > > > > Cc: stable@vger.kernel.org # 4.9.x
> > > > > > Fixes: ba14a194a434 ("fork: Add generic vmalloced stack support")
> > > > > > Link: https://lore.kernel.org/linux-integrity/Y4pIpxbjBdajymBJ@sol.localdomain/
> > > > > > Suggested-by: Eric Biggers <ebiggers@kernel.org>
> > > > > > Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
> > > > > > ---
> > > > > >  crypto/asymmetric_keys/public_key.c | 38 ++++++++++++++++-------------
> > > > > >  1 file changed, 21 insertions(+), 17 deletions(-)
> > > > >
> > > > > Reviewed-by: Eric Biggers <ebiggers@google.com>
> > > >
> > > > Hi David
> > > >
> > > > could you please take this patch in your repo, if it is ok?
> > >
> > > Kindly ask your support here. Has this patch been queued somewhere?
> > > Wasn't able to find it, also it is not in linux-next.
> > >
> >
> > The maintainer of asymmetric_keys (David Howells) is ignoring this patch, so
> > you'll need to find someone else to apply it.  Herbert Xu, the maintainer of the
> > crypto subsystem, might be willing to apply it.  Or maybe Jarkko Sakkinen, who
> > is a co-maintainer of the keyrings subsystem (but not asymmetric_keys, for some
> > reason; should that change?).
> 
> It is problematic that David isn't replying to this.  I have no idea
> if it will work, but I just reached out to him to see if I can draw
> his attention back to this ...

See my response to Eric.

BR, Jarkko

Re: [PATCH v5 2/2] KEYS: asymmetric: Copy sig and digest in public_key_verify_signature()

[Paul Moore]

On Thu, Feb 9, 2023 at 10:56 PM Jarkko Sakkinen <jarkko@kernel.org> wrote:
> On Thu, Feb 09, 2023 at 05:46:32PM -0500, Paul Moore wrote:
> > On Thu, Feb 9, 2023 at 1:53 PM Eric Biggers <ebiggers@kernel.org> wrote:
> > > On Thu, Feb 09, 2023 at 11:49:19AM +0100, Roberto Sassu wrote:
> > > > On Fri, 2023-01-27 at 09:27 +0100, Roberto Sassu wrote:
> > > > > On Thu, 2022-12-29 at 14:39 -0800, Eric Biggers wrote:
> > > > > > On Tue, Dec 27, 2022 at 03:27:40PM +0100, Roberto Sassu wrote:
> > > > > > > From: Roberto Sassu <roberto.sassu@huawei.com>
> > > > > > >
> > > > > > > Commit ac4e97abce9b8 ("scatterlist: sg_set_buf() argument must be in linear
> > > > > > > mapping") checks that both the signature and the digest reside in the
> > > > > > > linear mapping area.
> > > > > > >
> > > > > > > However, more recently commit ba14a194a434c ("fork: Add generic vmalloced
> > > > > > > stack support") made it possible to move the stack in the vmalloc area,
> > > > > > > which is not contiguous, and thus not suitable for sg_set_buf() which needs
> > > > > > > adjacent pages.
> > > > > > >
> > > > > > > Always make a copy of the signature and digest in the same buffer used to
> > > > > > > store the key and its parameters, and pass them to sg_init_one(). Prefer it
> > > > > > > to conditionally doing the copy if necessary, to keep the code simple. The
> > > > > > > buffer allocated with kmalloc() is in the linear mapping area.
> > > > > > >
> > > > > > > Cc: stable@vger.kernel.org # 4.9.x
> > > > > > > Fixes: ba14a194a434 ("fork: Add generic vmalloced stack support")
> > > > > > > Link: https://lore.kernel.org/linux-integrity/Y4pIpxbjBdajymBJ@sol.localdomain/
> > > > > > > Suggested-by: Eric Biggers <ebiggers@kernel.org>
> > > > > > > Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
> > > > > > > ---
> > > > > > >  crypto/asymmetric_keys/public_key.c | 38 ++++++++++++++++-------------
> > > > > > >  1 file changed, 21 insertions(+), 17 deletions(-)
> > > > > >
> > > > > > Reviewed-by: Eric Biggers <ebiggers@google.com>
> > > > >
> > > > > Hi David
> > > > >
> > > > > could you please take this patch in your repo, if it is ok?
> > > >
> > > > Kindly ask your support here. Has this patch been queued somewhere?
> > > > Wasn't able to find it, also it is not in linux-next.
> > > >
> > >
> > > The maintainer of asymmetric_keys (David Howells) is ignoring this patch, so
> > > you'll need to find someone else to apply it.  Herbert Xu, the maintainer of the
> > > crypto subsystem, might be willing to apply it.  Or maybe Jarkko Sakkinen, who
> > > is a co-maintainer of the keyrings subsystem (but not asymmetric_keys, for some
> > > reason; should that change?).
> >
> > It is problematic that David isn't replying to this.  I have no idea
> > if it will work, but I just reached out to him to see if I can draw
> > his attention back to this ...
>
> See my response to Eric.

Thanks Jarkko.

-- 
paul-moore.com

Re: [PATCH v5 2/2] KEYS: asymmetric: Copy sig and digest in public_key_verify_signature()

[Jarkko Sakkinen]

On Thu, Feb 09, 2023 at 06:53:37PM +0000, Eric Biggers wrote:
> On Thu, Feb 09, 2023 at 11:49:19AM +0100, Roberto Sassu wrote:
> > On Fri, 2023-01-27 at 09:27 +0100, Roberto Sassu wrote:
> > > On Thu, 2022-12-29 at 14:39 -0800, Eric Biggers wrote:
> > > > On Tue, Dec 27, 2022 at 03:27:40PM +0100, Roberto Sassu wrote:
> > > > > From: Roberto Sassu <roberto.sassu@huawei.com>
> > > > > 
> > > > > Commit ac4e97abce9b8 ("scatterlist: sg_set_buf() argument must be in linear
> > > > > mapping") checks that both the signature and the digest reside in the
> > > > > linear mapping area.
> > > > > 
> > > > > However, more recently commit ba14a194a434c ("fork: Add generic vmalloced
> > > > > stack support") made it possible to move the stack in the vmalloc area,
> > > > > which is not contiguous, and thus not suitable for sg_set_buf() which needs
> > > > > adjacent pages.
> > > > > 
> > > > > Always make a copy of the signature and digest in the same buffer used to
> > > > > store the key and its parameters, and pass them to sg_init_one(). Prefer it
> > > > > to conditionally doing the copy if necessary, to keep the code simple. The
> > > > > buffer allocated with kmalloc() is in the linear mapping area.
> > > > > 
> > > > > Cc: stable@vger.kernel.org # 4.9.x
> > > > > Fixes: ba14a194a434 ("fork: Add generic vmalloced stack support")
> > > > > Link: https://lore.kernel.org/linux-integrity/Y4pIpxbjBdajymBJ@sol.localdomain/
> > > > > Suggested-by: Eric Biggers <ebiggers@kernel.org>
> > > > > Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
> > > > > ---
> > > > >  crypto/asymmetric_keys/public_key.c | 38 ++++++++++++++++-------------
> > > > >  1 file changed, 21 insertions(+), 17 deletions(-)
> > > > 
> > > > Reviewed-by: Eric Biggers <ebiggers@google.com>
> > > 
> > > Hi David
> > > 
> > > could you please take this patch in your repo, if it is ok?
> > 
> > Kindly ask your support here. Has this patch been queued somewhere?
> > Wasn't able to find it, also it is not in linux-next.
> > 
> 
> The maintainer of asymmetric_keys (David Howells) is ignoring this patch, so
> you'll need to find someone else to apply it.  Herbert Xu, the maintainer of the
> crypto subsystem, might be willing to apply it.  Or maybe Jarkko Sakkinen, who
> is a co-maintainer of the keyrings subsystem (but not asymmetric_keys, for some
> reason; should that change?).

I can apply this if no objections?

BR, Jarkko

Re: [PATCH v5 2/2] KEYS: asymmetric: Copy sig and digest in public_key_verify_signature()

[Roberto Sassu]

On Fri, 2023-02-10 at 05:52 +0200, Jarkko Sakkinen wrote:
> On Thu, Feb 09, 2023 at 06:53:37PM +0000, Eric Biggers wrote:
> > On Thu, Feb 09, 2023 at 11:49:19AM +0100, Roberto Sassu wrote:
> > > On Fri, 2023-01-27 at 09:27 +0100, Roberto Sassu wrote:
> > > > On Thu, 2022-12-29 at 14:39 -0800, Eric Biggers wrote:
> > > > > On Tue, Dec 27, 2022 at 03:27:40PM +0100, Roberto Sassu wrote:
> > > > > > From: Roberto Sassu <roberto.sassu@huawei.com>
> > > > > > 
> > > > > > Commit ac4e97abce9b8 ("scatterlist: sg_set_buf() argument must be in linear
> > > > > > mapping") checks that both the signature and the digest reside in the
> > > > > > linear mapping area.
> > > > > > 
> > > > > > However, more recently commit ba14a194a434c ("fork: Add generic vmalloced
> > > > > > stack support") made it possible to move the stack in the vmalloc area,
> > > > > > which is not contiguous, and thus not suitable for sg_set_buf() which needs
> > > > > > adjacent pages.
> > > > > > 
> > > > > > Always make a copy of the signature and digest in the same buffer used to
> > > > > > store the key and its parameters, and pass them to sg_init_one(). Prefer it
> > > > > > to conditionally doing the copy if necessary, to keep the code simple. The
> > > > > > buffer allocated with kmalloc() is in the linear mapping area.
> > > > > > 
> > > > > > Cc: stable@vger.kernel.org # 4.9.x
> > > > > > Fixes: ba14a194a434 ("fork: Add generic vmalloced stack support")
> > > > > > Link: https://lore.kernel.org/linux-integrity/Y4pIpxbjBdajymBJ@sol.localdomain/
> > > > > > Suggested-by: Eric Biggers <ebiggers@kernel.org>
> > > > > > Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
> > > > > > ---
> > > > > >  crypto/asymmetric_keys/public_key.c | 38 ++++++++++++++++-------------
> > > > > >  1 file changed, 21 insertions(+), 17 deletions(-)
> > > > > 
> > > > > Reviewed-by: Eric Biggers <ebiggers@google.com>
> > > > 
> > > > Hi David
> > > > 
> > > > could you please take this patch in your repo, if it is ok?
> > > 
> > > Kindly ask your support here. Has this patch been queued somewhere?
> > > Wasn't able to find it, also it is not in linux-next.
> > > 
> > 
> > The maintainer of asymmetric_keys (David Howells) is ignoring this patch, so
> > you'll need to find someone else to apply it.  Herbert Xu, the maintainer of the
> > crypto subsystem, might be willing to apply it.  Or maybe Jarkko Sakkinen, who
> > is a co-maintainer of the keyrings subsystem (but not asymmetric_keys, for some
> > reason; should that change?).
> 
> I can apply this if no objections?

Hi Jarkko

I wasn't able to reach David about this patch. Could you please apply
it?

Thanks

Roberto

Re: [PATCH v5 2/2] KEYS: asymmetric: Copy sig and digest in public_key_verify_signature()

[Stefan Berger]

On 12/27/22 09:27, Roberto Sassu wrote:
> From: Roberto Sassu <roberto.sassu@huawei.com>
> 
> Commit ac4e97abce9b8 ("scatterlist: sg_set_buf() argument must be in linear
> mapping") checks that both the signature and the digest reside in the
> linear mapping area.
> 
> However, more recently commit ba14a194a434c ("fork: Add generic vmalloced
> stack support") made it possible to move the stack in the vmalloc area,
> which is not contiguous, and thus not suitable for sg_set_buf() which needs
> adjacent pages.
> 
> Always make a copy of the signature and digest in the same buffer used to
> store the key and its parameters, and pass them to sg_init_one(). Prefer it
> to conditionally doing the copy if necessary, to keep the code simple. The
> buffer allocated with kmalloc() is in the linear mapping area.
> 
> Cc: stable@vger.kernel.org # 4.9.x
> Fixes: ba14a194a434 ("fork: Add generic vmalloced stack support")
> Link: https://lore.kernel.org/linux-integrity/Y4pIpxbjBdajymBJ@sol.localdomain/
> Suggested-by: Eric Biggers <ebiggers@kernel.org>
> Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
> Reviewed-by: Eric Biggers <ebiggers@google.com>

I just ran into an issue with OpenBMC on ARM where EVM ECDSA signature verification failed due to invalid hashes being passed to the ECDSA signature verification algorithm. This patch here resolved the issue.

Tested-by: Stefan Berger <stefanb@linux.ibm.com>



> ---
>   crypto/asymmetric_keys/public_key.c | 38 ++++++++++++++++-------------
>   1 file changed, 21 insertions(+), 17 deletions(-)
> 
> diff --git a/crypto/asymmetric_keys/public_key.c b/crypto/asymmetric_keys/public_key.c
> index 2f8352e88860..49a3f7c01149 100644
> --- a/crypto/asymmetric_keys/public_key.c
> +++ b/crypto/asymmetric_keys/public_key.c
> @@ -360,9 +360,10 @@ int public_key_verify_signature(const struct public_key *pkey,
>   	struct crypto_wait cwait;
>   	struct crypto_akcipher *tfm;
>   	struct akcipher_request *req;
> -	struct scatterlist src_sg[2];
> +	struct scatterlist src_sg;
>   	char alg_name[CRYPTO_MAX_ALG_NAME];
> -	char *key, *ptr;
> +	char *buf, *ptr;
> +	size_t buf_len;
>   	int ret;
>   
>   	pr_devel("==>%s()\n", __func__);
> @@ -400,34 +401,37 @@ int public_key_verify_signature(const struct public_key *pkey,
>   	if (!req)
>   		goto error_free_tfm;
>   
> -	key = kmalloc(pkey->keylen + sizeof(u32) * 2 + pkey->paramlen,
> -		      GFP_KERNEL);
> -	if (!key)
> +	buf_len = max_t(size_t, pkey->keylen + sizeof(u32) * 2 + pkey->paramlen,
> +			sig->s_size + sig->digest_size);
> +
> +	buf = kmalloc(buf_len, GFP_KERNEL);
> +	if (!buf)
>   		goto error_free_req;
>   
> -	memcpy(key, pkey->key, pkey->keylen);
> -	ptr = key + pkey->keylen;
> +	memcpy(buf, pkey->key, pkey->keylen);
> +	ptr = buf + pkey->keylen;
>   	ptr = pkey_pack_u32(ptr, pkey->algo);
>   	ptr = pkey_pack_u32(ptr, pkey->paramlen);
>   	memcpy(ptr, pkey->params, pkey->paramlen);
>   
>   	if (pkey->key_is_private)
> -		ret = crypto_akcipher_set_priv_key(tfm, key, pkey->keylen);
> +		ret = crypto_akcipher_set_priv_key(tfm, buf, pkey->keylen);
>   	else
> -		ret = crypto_akcipher_set_pub_key(tfm, key, pkey->keylen);
> +		ret = crypto_akcipher_set_pub_key(tfm, buf, pkey->keylen);
>   	if (ret)
> -		goto error_free_key;
> +		goto error_free_buf;
>   
>   	if (strcmp(pkey->pkey_algo, "sm2") == 0 && sig->data_size) {
>   		ret = cert_sig_digest_update(sig, tfm);
>   		if (ret)
> -			goto error_free_key;
> +			goto error_free_buf;
>   	}
>   
> -	sg_init_table(src_sg, 2);
> -	sg_set_buf(&src_sg[0], sig->s, sig->s_size);
> -	sg_set_buf(&src_sg[1], sig->digest, sig->digest_size);
> -	akcipher_request_set_crypt(req, src_sg, NULL, sig->s_size,
> +	memcpy(buf, sig->s, sig->s_size);
> +	memcpy(buf + sig->s_size, sig->digest, sig->digest_size);
> +
> +	sg_init_one(&src_sg, buf, sig->s_size + sig->digest_size);
> +	akcipher_request_set_crypt(req, &src_sg, NULL, sig->s_size,
>   				   sig->digest_size);
>   	crypto_init_wait(&cwait);
>   	akcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG |
> @@ -435,8 +439,8 @@ int public_key_verify_signature(const struct public_key *pkey,
>   				      crypto_req_done, &cwait);
>   	ret = crypto_wait_req(crypto_akcipher_verify(req), &cwait);
>   
> -error_free_key:
> -	kfree(key);
> +error_free_buf:
> +	kfree(buf);
>   error_free_req:
>   	akcipher_request_free(req);
>   error_free_tfm:

Re: [PATCH v5 2/2] KEYS: asymmetric: Copy sig and digest in public_key_verify_signature()

[Roberto Sassu]

On Thu, 2023-06-01 at 17:00 -0400, Stefan Berger wrote:
> 
> On 12/27/22 09:27, Roberto Sassu wrote:
> > From: Roberto Sassu <roberto.sassu@huawei.com>
> > 
> > Commit ac4e97abce9b8 ("scatterlist: sg_set_buf() argument must be in linear
> > mapping") checks that both the signature and the digest reside in the
> > linear mapping area.
> > 
> > However, more recently commit ba14a194a434c ("fork: Add generic vmalloced
> > stack support") made it possible to move the stack in the vmalloc area,
> > which is not contiguous, and thus not suitable for sg_set_buf() which needs
> > adjacent pages.
> > 
> > Always make a copy of the signature and digest in the same buffer used to
> > store the key and its parameters, and pass them to sg_init_one(). Prefer it
> > to conditionally doing the copy if necessary, to keep the code simple. The
> > buffer allocated with kmalloc() is in the linear mapping area.
> > 
> > Cc: stable@vger.kernel.org # 4.9.x
> > Fixes: ba14a194a434 ("fork: Add generic vmalloced stack support")
> > Link: https://lore.kernel.org/linux-integrity/Y4pIpxbjBdajymBJ@sol.localdomain/
> > Suggested-by: Eric Biggers <ebiggers@kernel.org>
> > Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
> > Reviewed-by: Eric Biggers <ebiggers@google.com>
> 
> I just ran into an issue with OpenBMC on ARM where EVM ECDSA signature verification failed due to invalid hashes being passed to the ECDSA signature verification algorithm. This patch here resolved the issue.
> 
> Tested-by: Stefan Berger <stefanb@linux.ibm.com>

Thanks, Stefan.

I did multiple attempts to have the patch included, but I didn't have
any luck with the maintainers (David, Jarkko).

It would be awesome if any maintainer picks it.

Thanks!

Roberto

> ---
> >   crypto/asymmetric_keys/public_key.c | 38 ++++++++++++++++-------------
> >   1 file changed, 21 insertions(+), 17 deletions(-)
> > 
> > diff --git a/crypto/asymmetric_keys/public_key.c b/crypto/asymmetric_keys/public_key.c
> > index 2f8352e88860..49a3f7c01149 100644
> > --- a/crypto/asymmetric_keys/public_key.c
> > +++ b/crypto/asymmetric_keys/public_key.c
> > @@ -360,9 +360,10 @@ int public_key_verify_signature(const struct public_key *pkey,
> >   	struct crypto_wait cwait;
> >   	struct crypto_akcipher *tfm;
> >   	struct akcipher_request *req;
> > -	struct scatterlist src_sg[2];
> > +	struct scatterlist src_sg;
> >   	char alg_name[CRYPTO_MAX_ALG_NAME];
> > -	char *key, *ptr;
> > +	char *buf, *ptr;
> > +	size_t buf_len;
> >   	int ret;
> >   
> >   	pr_devel("==>%s()\n", __func__);
> > @@ -400,34 +401,37 @@ int public_key_verify_signature(const struct public_key *pkey,
> >   	if (!req)
> >   		goto error_free_tfm;
> >   
> > -	key = kmalloc(pkey->keylen + sizeof(u32) * 2 + pkey->paramlen,
> > -		      GFP_KERNEL);
> > -	if (!key)
> > +	buf_len = max_t(size_t, pkey->keylen + sizeof(u32) * 2 + pkey->paramlen,
> > +			sig->s_size + sig->digest_size);
> > +
> > +	buf = kmalloc(buf_len, GFP_KERNEL);
> > +	if (!buf)
> >   		goto error_free_req;
> >   
> > -	memcpy(key, pkey->key, pkey->keylen);
> > -	ptr = key + pkey->keylen;
> > +	memcpy(buf, pkey->key, pkey->keylen);
> > +	ptr = buf + pkey->keylen;
> >   	ptr = pkey_pack_u32(ptr, pkey->algo);
> >   	ptr = pkey_pack_u32(ptr, pkey->paramlen);
> >   	memcpy(ptr, pkey->params, pkey->paramlen);
> >   
> >   	if (pkey->key_is_private)
> > -		ret = crypto_akcipher_set_priv_key(tfm, key, pkey->keylen);
> > +		ret = crypto_akcipher_set_priv_key(tfm, buf, pkey->keylen);
> >   	else
> > -		ret = crypto_akcipher_set_pub_key(tfm, key, pkey->keylen);
> > +		ret = crypto_akcipher_set_pub_key(tfm, buf, pkey->keylen);
> >   	if (ret)
> > -		goto error_free_key;
> > +		goto error_free_buf;
> >   
> >   	if (strcmp(pkey->pkey_algo, "sm2") == 0 && sig->data_size) {
> >   		ret = cert_sig_digest_update(sig, tfm);
> >   		if (ret)
> > -			goto error_free_key;
> > +			goto error_free_buf;
> >   	}
> >   
> > -	sg_init_table(src_sg, 2);
> > -	sg_set_buf(&src_sg[0], sig->s, sig->s_size);
> > -	sg_set_buf(&src_sg[1], sig->digest, sig->digest_size);
> > -	akcipher_request_set_crypt(req, src_sg, NULL, sig->s_size,
> > +	memcpy(buf, sig->s, sig->s_size);
> > +	memcpy(buf + sig->s_size, sig->digest, sig->digest_size);
> > +
> > +	sg_init_one(&src_sg, buf, sig->s_size + sig->digest_size);
> > +	akcipher_request_set_crypt(req, &src_sg, NULL, sig->s_size,
> >   				   sig->digest_size);
> >   	crypto_init_wait(&cwait);
> >   	akcipher_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG |
> > @@ -435,8 +439,8 @@ int public_key_verify_signature(const struct public_key *pkey,
> >   				      crypto_req_done, &cwait);
> >   	ret = crypto_wait_req(crypto_akcipher_verify(req), &cwait);
> >   
> > -error_free_key:
> > -	kfree(key);
> > +error_free_buf:
> > +	kfree(buf);
> >   error_free_req:
> >   	akcipher_request_free(req);
> >   error_free_tfm:

Re: [PATCH v5 2/2] KEYS: asymmetric: Copy sig and digest in public_key_verify_signature()

[Eric Biggers]

On Fri, Jun 02, 2023 at 11:17:04AM +0200, Roberto Sassu wrote:
> On Thu, 2023-06-01 at 17:00 -0400, Stefan Berger wrote:
> > 
> > On 12/27/22 09:27, Roberto Sassu wrote:
> > > From: Roberto Sassu <roberto.sassu@huawei.com>
> > > 
> > > Commit ac4e97abce9b8 ("scatterlist: sg_set_buf() argument must be in linear
> > > mapping") checks that both the signature and the digest reside in the
> > > linear mapping area.
> > > 
> > > However, more recently commit ba14a194a434c ("fork: Add generic vmalloced
> > > stack support") made it possible to move the stack in the vmalloc area,
> > > which is not contiguous, and thus not suitable for sg_set_buf() which needs
> > > adjacent pages.
> > > 
> > > Always make a copy of the signature and digest in the same buffer used to
> > > store the key and its parameters, and pass them to sg_init_one(). Prefer it
> > > to conditionally doing the copy if necessary, to keep the code simple. The
> > > buffer allocated with kmalloc() is in the linear mapping area.
> > > 
> > > Cc: stable@vger.kernel.org # 4.9.x
> > > Fixes: ba14a194a434 ("fork: Add generic vmalloced stack support")
> > > Link: https://lore.kernel.org/linux-integrity/Y4pIpxbjBdajymBJ@sol.localdomain/
> > > Suggested-by: Eric Biggers <ebiggers@kernel.org>
> > > Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
> > > Reviewed-by: Eric Biggers <ebiggers@google.com>
> > 
> > I just ran into an issue with OpenBMC on ARM where EVM ECDSA signature verification failed due to invalid hashes being passed to the ECDSA signature verification algorithm. This patch here resolved the issue.
> > 
> > Tested-by: Stefan Berger <stefanb@linux.ibm.com>
> 
> Thanks, Stefan.
> 
> I did multiple attempts to have the patch included, but I didn't have
> any luck with the maintainers (David, Jarkko).
> 
> It would be awesome if any maintainer picks it.
> 
> Thanks!
> 

As the maintainers are ignoring this patch, you could try the "maintainers of
last resort" (Andrew Morton or Linus Torvalds).

- Eric

Re: [PATCH v5 2/2] KEYS: asymmetric: Copy sig and digest in public_key_verify_signature()

[Roberto Sassu]

On Fri, 2023-06-02 at 06:17 -0700, Eric Biggers wrote:
> On Fri, Jun 02, 2023 at 11:17:04AM +0200, Roberto Sassu wrote:
> > On Thu, 2023-06-01 at 17:00 -0400, Stefan Berger wrote:
> > > On 12/27/22 09:27, Roberto Sassu wrote:
> > > > From: Roberto Sassu <roberto.sassu@huawei.com>
> > > > 
> > > > Commit ac4e97abce9b8 ("scatterlist: sg_set_buf() argument must be in linear
> > > > mapping") checks that both the signature and the digest reside in the
> > > > linear mapping area.
> > > > 
> > > > However, more recently commit ba14a194a434c ("fork: Add generic vmalloced
> > > > stack support") made it possible to move the stack in the vmalloc area,
> > > > which is not contiguous, and thus not suitable for sg_set_buf() which needs
> > > > adjacent pages.
> > > > 
> > > > Always make a copy of the signature and digest in the same buffer used to
> > > > store the key and its parameters, and pass them to sg_init_one(). Prefer it
> > > > to conditionally doing the copy if necessary, to keep the code simple. The
> > > > buffer allocated with kmalloc() is in the linear mapping area.
> > > > 
> > > > Cc: stable@vger.kernel.org # 4.9.x
> > > > Fixes: ba14a194a434 ("fork: Add generic vmalloced stack support")
> > > > Link: https://lore.kernel.org/linux-integrity/Y4pIpxbjBdajymBJ@sol.localdomain/
> > > > Suggested-by: Eric Biggers <ebiggers@kernel.org>
> > > > Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
> > > > Reviewed-by: Eric Biggers <ebiggers@google.com>
> > > 
> > > I just ran into an issue with OpenBMC on ARM where EVM ECDSA signature verification failed due to invalid hashes being passed to the ECDSA signature verification algorithm. This patch here resolved the issue.
> > > 
> > > Tested-by: Stefan Berger <stefanb@linux.ibm.com>
> > 
> > Thanks, Stefan.
> > 
> > I did multiple attempts to have the patch included, but I didn't have
> > any luck with the maintainers (David, Jarkko).
> > 
> > It would be awesome if any maintainer picks it.
> > 
> > Thanks!
> > 
> 
> As the maintainers are ignoring this patch, you could try the "maintainers of
> last resort" (Andrew Morton or Linus Torvalds).

Thanks, will do.

Roberto