diff mbox series

efi_loader: efi_variable_parse_signature() returns NULL on error

Message ID 20200507001318.GA6451@nox.fritz.box
State Accepted
Commit 9ad15227bb92acc2bf73c60da1bcf2ae3774246d
Headers show
Series efi_loader: efi_variable_parse_signature() returns NULL on error | expand

Commit Message

Patrick Wildt May 7, 2020, 12:13 a.m. UTC
efi_variable_parse_signature() returns NULL on error, so IS_NULL()
is an incorrect check.  The goto err leads to pkcs7_free_message(),
which works fine on a NULL ptr.

Signed-off-by: Patrick Wildt <patrick at blueri.se>

Comments

AKASHI Takahiro May 7, 2020, 7:14 a.m. UTC | #1
On Thu, May 07, 2020 at 02:13:18AM +0200, Patrick Wildt wrote:
> efi_variable_parse_signature() returns NULL on error, so IS_NULL()
> is an incorrect check.  The goto err leads to pkcs7_free_message(),
> which works fine on a NULL ptr.
> 
> Signed-off-by: Patrick Wildt <patrick at blueri.se>

Reviewed-by: AKASHI Takahiro <takahiro.akashi at linaro.org>
> 
> diff --git a/lib/efi_loader/efi_variable.c b/lib/efi_loader/efi_variable.c
> index 58f8fae358..c5fe896de2 100644
> --- a/lib/efi_loader/efi_variable.c
> +++ b/lib/efi_loader/efi_variable.c
> @@ -519,9 +519,8 @@ static efi_status_t efi_variable_authenticate(u16 *variable,
>  	var_sig = efi_variable_parse_signature(auth->auth_info.cert_data,
>  					       auth->auth_info.hdr.dwLength
>  						   - sizeof(auth->auth_info));
> -	if (IS_ERR(var_sig)) {
> +	if (!var_sig) {
>  		debug("Parsing variable's signature failed\n");
> -		var_sig = NULL;
>  		goto err;
>  	}
>
AKASHI Takahiro May 7, 2020, 7:15 a.m. UTC | #2
On Thu, May 07, 2020 at 02:13:18AM +0200, Patrick Wildt wrote:
> efi_variable_parse_signature() returns NULL on error, so IS_NULL()
> is an incorrect check.  The goto err leads to pkcs7_free_message(),
> which works fine on a NULL ptr.
> 
> Signed-off-by: Patrick Wildt <patrick at blueri.se>

Reviewed-by: AKASHI Takahiro <takahiro.akashi at linaro.org>

> 
> diff --git a/lib/efi_loader/efi_variable.c b/lib/efi_loader/efi_variable.c
> index 58f8fae358..c5fe896de2 100644
> --- a/lib/efi_loader/efi_variable.c
> +++ b/lib/efi_loader/efi_variable.c
> @@ -519,9 +519,8 @@ static efi_status_t efi_variable_authenticate(u16 *variable,
>  	var_sig = efi_variable_parse_signature(auth->auth_info.cert_data,
>  					       auth->auth_info.hdr.dwLength
>  						   - sizeof(auth->auth_info));
> -	if (IS_ERR(var_sig)) {
> +	if (!var_sig) {
>  		debug("Parsing variable's signature failed\n");
> -		var_sig = NULL;
>  		goto err;
>  	}
>
Heinrich Schuchardt May 7, 2020, 1:53 p.m. UTC | #3
On 07.05.20 09:15, AKASHI Takahiro wrote:
> On Thu, May 07, 2020 at 02:13:18AM +0200, Patrick Wildt wrote:
>> efi_variable_parse_signature() returns NULL on error, so IS_NULL()

IS_NULL() seems to be a typo. I will replace it by IS_ERR() when merging.

>> is an incorrect check.  The goto err leads to pkcs7_free_message(),
>> which works fine on a NULL ptr.
>>
>> Signed-off-by: Patrick Wildt <patrick at blueri.se>
>
> Reviewed-by: AKASHI Takahiro <takahiro.akashi at linaro.org>

Hello Takahiro,

there is a second instance of the same error:

lib/efi_loader/efi_variable.c:412:

??????? msg = pkcs7_parse_message(ebuf, ebuflen);
??????? free(ebuf);
out:
????????if (IS_ERR(msg))
????????????????return NULL;

Please, send a patch for that one too.

Best regards

Heinrich


>
>>
>> diff --git a/lib/efi_loader/efi_variable.c b/lib/efi_loader/efi_variable.c
>> index 58f8fae358..c5fe896de2 100644
>> --- a/lib/efi_loader/efi_variable.c
>> +++ b/lib/efi_loader/efi_variable.c
>> @@ -519,9 +519,8 @@ static efi_status_t efi_variable_authenticate(u16 *variable,
>>  	var_sig = efi_variable_parse_signature(auth->auth_info.cert_data,
>>  					       auth->auth_info.hdr.dwLength
>>  						   - sizeof(auth->auth_info));
>> -	if (IS_ERR(var_sig)) {
>> +	if (!var_sig) {
>>  		debug("Parsing variable's signature failed\n");
>> -		var_sig = NULL;
>>  		goto err;
>>  	}
>>
Patrick Wildt May 7, 2020, 11:18 p.m. UTC | #4
On Thu, May 07, 2020 at 03:53:29PM +0200, Heinrich Schuchardt wrote:
> On 07.05.20 09:15, AKASHI Takahiro wrote:
> > On Thu, May 07, 2020 at 02:13:18AM +0200, Patrick Wildt wrote:
> >> efi_variable_parse_signature() returns NULL on error, so IS_NULL()
> 
> IS_NULL() seems to be a typo. I will replace it by IS_ERR() when merging.

Hi,

Yes, sorry.

> >> is an incorrect check.  The goto err leads to pkcs7_free_message(),
> >> which works fine on a NULL ptr.
> >>
> >> Signed-off-by: Patrick Wildt <patrick at blueri.se>
> >
> > Reviewed-by: AKASHI Takahiro <takahiro.akashi at linaro.org>
> 
> Hello Takahiro,
> 
> there is a second instance of the same error:
> 
> lib/efi_loader/efi_variable.c:412:
> 
> ??????? msg = pkcs7_parse_message(ebuf, ebuflen);
> ??????? free(ebuf);
> out:
> ????????if (IS_ERR(msg))
> ????????????????return NULL;
> 
> Please, send a patch for that one too.
> 
> Best regards
> 
> Heinrich

No, that is ok.  pkcs7_parse_message() returns an ERR_PTR() on failure,
as you saw in my other diff.  That's why IS_ERR(msg) is fine here, and
we can return NULL.

Best regards,
Patrick

> >
> >>
> >> diff --git a/lib/efi_loader/efi_variable.c b/lib/efi_loader/efi_variable.c
> >> index 58f8fae358..c5fe896de2 100644
> >> --- a/lib/efi_loader/efi_variable.c
> >> +++ b/lib/efi_loader/efi_variable.c
> >> @@ -519,9 +519,8 @@ static efi_status_t efi_variable_authenticate(u16 *variable,
> >>  	var_sig = efi_variable_parse_signature(auth->auth_info.cert_data,
> >>  					       auth->auth_info.hdr.dwLength
> >>  						   - sizeof(auth->auth_info));
> >> -	if (IS_ERR(var_sig)) {
> >> +	if (!var_sig) {
> >>  		debug("Parsing variable's signature failed\n");
> >> -		var_sig = NULL;
> >>  		goto err;
> >>  	}
> >>
>
diff mbox series

Patch

diff --git a/lib/efi_loader/efi_variable.c b/lib/efi_loader/efi_variable.c
index 58f8fae358..c5fe896de2 100644
--- a/lib/efi_loader/efi_variable.c
+++ b/lib/efi_loader/efi_variable.c
@@ -519,9 +519,8 @@  static efi_status_t efi_variable_authenticate(u16 *variable,
 	var_sig = efi_variable_parse_signature(auth->auth_info.cert_data,
 					       auth->auth_info.hdr.dwLength
 						   - sizeof(auth->auth_info));
-	if (IS_ERR(var_sig)) {
+	if (!var_sig) {
 		debug("Parsing variable's signature failed\n");
-		var_sig = NULL;
 		goto err;
 	}