[PATCH v2] qga-win: Free GMatchInfo properly

[PATCH v2] qga-win: Free GMatchInfo properly

[Kostiantyn Kostiuk]

The g_regex_match function creates match_info even if it
returns FALSE. So we should always call g_match_info_free.
A better solution is using g_autoptr for match_info variable.

Signed-off-by: Kostiantyn Kostiuk <konstantin@daynix.com>
---
 qga/commands-win32.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/qga/commands-win32.c b/qga/commands-win32.c
index 300b87c859..785a5cc6b2 100644
--- a/qga/commands-win32.c
+++ b/qga/commands-win32.c
@@ -2494,7 +2494,7 @@ GuestDeviceInfoList *qmp_guest_get_devices(Error **errp)
             continue;
         }
         for (j = 0; hw_ids[j] != NULL; j++) {
-            GMatchInfo *match_info;
+            g_autoptr(GMatchInfo) match_info;
             GuestDeviceIdPCI *id;
             if (!g_regex_match(device_pci_re, hw_ids[j], 0, &match_info)) {
                 continue;
@@ -2511,7 +2511,6 @@ GuestDeviceInfoList *qmp_guest_get_devices(Error **errp)
             id->vendor_id = g_ascii_strtoull(vendor_id, NULL, 16);
             id->device_id = g_ascii_strtoull(device_id, NULL, 16);
 
-            g_match_info_free(match_info);
             break;
         }
         if (skip) {
-- 
2.25.1

Re: [PATCH v2] qga-win: Free GMatchInfo properly

[Daniel P. Berrangé]

On Thu, Jun 10, 2021 at 06:58:11PM +0300, Kostiantyn Kostiuk wrote:
> The g_regex_match function creates match_info even if it
> returns FALSE. So we should always call g_match_info_free.
> A better solution is using g_autoptr for match_info variable.
> 
> Signed-off-by: Kostiantyn Kostiuk <konstantin@daynix.com>
> ---
>  qga/commands-win32.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/qga/commands-win32.c b/qga/commands-win32.c
> index 300b87c859..785a5cc6b2 100644
> --- a/qga/commands-win32.c
> +++ b/qga/commands-win32.c
> @@ -2494,7 +2494,7 @@ GuestDeviceInfoList *qmp_guest_get_devices(Error **errp)
>              continue;
>          }
>          for (j = 0; hw_ids[j] != NULL; j++) {
> -            GMatchInfo *match_info;
> +            g_autoptr(GMatchInfo) match_info;

This should be initialized to NULL otherwise...

>              GuestDeviceIdPCI *id;
>              if (!g_regex_match(device_pci_re, hw_ids[j], 0, &match_info)) {
>                  continue;

this continue will trigger freeing of unintialized memory

Essentially all g_auto* variables should be init to NULL
at all times, even if it currently looks harmless.

> @@ -2511,7 +2511,6 @@ GuestDeviceInfoList *qmp_guest_get_devices(Error **errp)
>              id->vendor_id = g_ascii_strtoull(vendor_id, NULL, 16);
>              id->device_id = g_ascii_strtoull(device_id, NULL, 16);
>  
> -            g_match_info_free(match_info);
>              break;
>          }
>          if (skip) {

Regards,
Daniel
-- 
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Re: [PATCH v2] qga-win: Free GMatchInfo properly

[Philippe Mathieu-Daudé]

On 6/10/21 5:58 PM, Kostiantyn Kostiuk wrote:
> The g_regex_match function creates match_info even if it
> returns FALSE. So we should always call g_match_info_free.
> A better solution is using g_autoptr for match_info variable.
> 
> Signed-off-by: Kostiantyn Kostiuk <konstantin@daynix.com>
> ---
>  qga/commands-win32.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)

Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>

Re: [PATCH v2] qga-win: Free GMatchInfo properly

[Konstantin Kostiuk]

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On Thu, Jun 10, 2021 at 7:02 PM Daniel P. Berrangé <berrange@redhat.com>
wrote:

> On Thu, Jun 10, 2021 at 06:58:11PM +0300, Kostiantyn Kostiuk wrote:
> > The g_regex_match function creates match_info even if it
> > returns FALSE. So we should always call g_match_info_free.
> > A better solution is using g_autoptr for match_info variable.
> >
> > Signed-off-by: Kostiantyn Kostiuk <konstantin@daynix.com>
> > ---
> >  qga/commands-win32.c | 3 +--
> >  1 file changed, 1 insertion(+), 2 deletions(-)
> >
> > diff --git a/qga/commands-win32.c b/qga/commands-win32.c
> > index 300b87c859..785a5cc6b2 100644
> > --- a/qga/commands-win32.c
> > +++ b/qga/commands-win32.c
> > @@ -2494,7 +2494,7 @@ GuestDeviceInfoList *qmp_guest_get_devices(Error
> **errp)
> >              continue;
> >          }
> >          for (j = 0; hw_ids[j] != NULL; j++) {
> > -            GMatchInfo *match_info;
> > +            g_autoptr(GMatchInfo) match_info;
>
> This should be initialized to NULL otherwise...
>
> >              GuestDeviceIdPCI *id;
> >              if (!g_regex_match(device_pci_re, hw_ids[j], 0,
> &match_info)) {
> >                  continue;
>
> this continue will trigger freeing of unintialized memory
>

But we always call match_info, so match_info is always initialized.
The g_regex_match function creates match_info even if it returns FALSE.


>
> Essentially all g_auto* variables should be init to NULL
> at all times, even if it currently looks harmless.
>
> > @@ -2511,7 +2511,6 @@ GuestDeviceInfoList *qmp_guest_get_devices(Error
> **errp)
> >              id->vendor_id = g_ascii_strtoull(vendor_id, NULL, 16);
> >              id->device_id = g_ascii_strtoull(device_id, NULL, 16);
> >
> > -            g_match_info_free(match_info);
> >              break;
> >          }
> >          if (skip) {
>
> Regards,
> Daniel
> --
> |: https://berrange.com      -o-
> https://www.flickr.com/photos/dberrange :|
> |: https://libvirt.org         -o-
> https://fstop138.berrange.com :|
> |: https://entangle-photo.org    -o-
> https://www.instagram.com/dberrange :|
>
>

Best wishes,
Kostiantyn Kostiuk

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Re: [PATCH v2] qga-win: Free GMatchInfo properly

[Daniel P. Berrangé]

On Thu, Jun 10, 2021 at 07:08:36PM +0300, Konstantin Kostiuk wrote:
> On Thu, Jun 10, 2021 at 7:02 PM Daniel P. Berrangé <berrange@redhat.com>
> wrote:
> 
> > On Thu, Jun 10, 2021 at 06:58:11PM +0300, Kostiantyn Kostiuk wrote:
> > > The g_regex_match function creates match_info even if it
> > > returns FALSE. So we should always call g_match_info_free.
> > > A better solution is using g_autoptr for match_info variable.
> > >
> > > Signed-off-by: Kostiantyn Kostiuk <konstantin@daynix.com>
> > > ---
> > >  qga/commands-win32.c | 3 +--
> > >  1 file changed, 1 insertion(+), 2 deletions(-)
> > >
> > > diff --git a/qga/commands-win32.c b/qga/commands-win32.c
> > > index 300b87c859..785a5cc6b2 100644
> > > --- a/qga/commands-win32.c
> > > +++ b/qga/commands-win32.c
> > > @@ -2494,7 +2494,7 @@ GuestDeviceInfoList *qmp_guest_get_devices(Error
> > **errp)
> > >              continue;
> > >          }
> > >          for (j = 0; hw_ids[j] != NULL; j++) {
> > > -            GMatchInfo *match_info;
> > > +            g_autoptr(GMatchInfo) match_info;
> >
> > This should be initialized to NULL otherwise...
> >
> > >              GuestDeviceIdPCI *id;
> > >              if (!g_regex_match(device_pci_re, hw_ids[j], 0,
> > &match_info)) {
> > >                  continue;
> >
> > this continue will trigger freeing of unintialized memory
> >
> 
> But we always call match_info, so match_info is always initialized.
> The g_regex_match function creates match_info even if it returns FALSE.

Opps, yes, you are right.

Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>


Regards,
Daniel
-- 
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Re: [PATCH v2] qga-win: Free GMatchInfo properly

[Konstantin Kostiuk]

[-- Attachment #1: Type: text/plain, Size: 2083 bytes --]

CC Michael Roth

On Thu, Jun 10, 2021 at 7:14 PM Daniel P. Berrangé <berrange@redhat.com>
wrote:

> On Thu, Jun 10, 2021 at 07:08:36PM +0300, Konstantin Kostiuk wrote:
> > On Thu, Jun 10, 2021 at 7:02 PM Daniel P. Berrangé <berrange@redhat.com>
> > wrote:
> >
> > > On Thu, Jun 10, 2021 at 06:58:11PM +0300, Kostiantyn Kostiuk wrote:
> > > > The g_regex_match function creates match_info even if it
> > > > returns FALSE. So we should always call g_match_info_free.
> > > > A better solution is using g_autoptr for match_info variable.
> > > >
> > > > Signed-off-by: Kostiantyn Kostiuk <konstantin@daynix.com>
> > > > ---
> > > >  qga/commands-win32.c | 3 +--
> > > >  1 file changed, 1 insertion(+), 2 deletions(-)
> > > >
> > > > diff --git a/qga/commands-win32.c b/qga/commands-win32.c
> > > > index 300b87c859..785a5cc6b2 100644
> > > > --- a/qga/commands-win32.c
> > > > +++ b/qga/commands-win32.c
> > > > @@ -2494,7 +2494,7 @@ GuestDeviceInfoList
> *qmp_guest_get_devices(Error
> > > **errp)
> > > >              continue;
> > > >          }
> > > >          for (j = 0; hw_ids[j] != NULL; j++) {
> > > > -            GMatchInfo *match_info;
> > > > +            g_autoptr(GMatchInfo) match_info;
> > >
> > > This should be initialized to NULL otherwise...
> > >
> > > >              GuestDeviceIdPCI *id;
> > > >              if (!g_regex_match(device_pci_re, hw_ids[j], 0,
> > > &match_info)) {
> > > >                  continue;
> > >
> > > this continue will trigger freeing of unintialized memory
> > >
> >
> > But we always call match_info, so match_info is always initialized.
> > The g_regex_match function creates match_info even if it returns FALSE.
>
> Opps, yes, you are right.
>
> Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
>
>
> Regards,
> Daniel
> --
> |: https://berrange.com      -o-
> https://www.flickr.com/photos/dberrange :|
> |: https://libvirt.org         -o-
> https://fstop138.berrange.com :|
> |: https://entangle-photo.org    -o-
> https://www.instagram.com/dberrange :|
>
>

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Re: [PATCH v2] qga-win: Free GMatchInfo properly

[Konstantin Kostiuk]

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ping

On Wed, Jul 14, 2021 at 10:26 AM Konstantin Kostiuk <konstantin@daynix.com>
wrote:

> CC Michael Roth
>
> On Thu, Jun 10, 2021 at 7:14 PM Daniel P. Berrangé <berrange@redhat.com>
> wrote:
>
>> On Thu, Jun 10, 2021 at 07:08:36PM +0300, Konstantin Kostiuk wrote:
>> > On Thu, Jun 10, 2021 at 7:02 PM Daniel P. Berrangé <berrange@redhat.com
>> >
>> > wrote:
>> >
>> > > On Thu, Jun 10, 2021 at 06:58:11PM +0300, Kostiantyn Kostiuk wrote:
>> > > > The g_regex_match function creates match_info even if it
>> > > > returns FALSE. So we should always call g_match_info_free.
>> > > > A better solution is using g_autoptr for match_info variable.
>> > > >
>> > > > Signed-off-by: Kostiantyn Kostiuk <konstantin@daynix.com>
>> > > > ---
>> > > >  qga/commands-win32.c | 3 +--
>> > > >  1 file changed, 1 insertion(+), 2 deletions(-)
>> > > >
>> > > > diff --git a/qga/commands-win32.c b/qga/commands-win32.c
>> > > > index 300b87c859..785a5cc6b2 100644
>> > > > --- a/qga/commands-win32.c
>> > > > +++ b/qga/commands-win32.c
>> > > > @@ -2494,7 +2494,7 @@ GuestDeviceInfoList
>> *qmp_guest_get_devices(Error
>> > > **errp)
>> > > >              continue;
>> > > >          }
>> > > >          for (j = 0; hw_ids[j] != NULL; j++) {
>> > > > -            GMatchInfo *match_info;
>> > > > +            g_autoptr(GMatchInfo) match_info;
>> > >
>> > > This should be initialized to NULL otherwise...
>> > >
>> > > >              GuestDeviceIdPCI *id;
>> > > >              if (!g_regex_match(device_pci_re, hw_ids[j], 0,
>> > > &match_info)) {
>> > > >                  continue;
>> > >
>> > > this continue will trigger freeing of unintialized memory
>> > >
>> >
>> > But we always call match_info, so match_info is always initialized.
>> > The g_regex_match function creates match_info even if it returns FALSE.
>>
>> Opps, yes, you are right.
>>
>> Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
>>
>>
>> Regards,
>> Daniel
>> --
>> |: https://berrange.com      -o-
>> https://www.flickr.com/photos/dberrange :|
>> |: https://libvirt.org         -o-
>> https://fstop138.berrange.com :|
>> |: https://entangle-photo.org    -o-
>> https://www.instagram.com/dberrange :|
>>
>>

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Re: [PATCH-for-6.1 v2] qga-win: Free GMatchInfo properly

[Philippe Mathieu-Daudé]

Still candidate for 6.1.

On 7/28/21 9:54 AM, Konstantin Kostiuk wrote:
> ping
> 
> On Wed, Jul 14, 2021 at 10:26 AM Konstantin Kostiuk
> <konstantin@daynix.com <mailto:konstantin@daynix.com>> wrote:
> 
>     CC Michael Roth
> 
>     On Thu, Jun 10, 2021 at 7:14 PM Daniel P. Berrangé
>     <berrange@redhat.com <mailto:berrange@redhat.com>> wrote:
> 
>         On Thu, Jun 10, 2021 at 07:08:36PM +0300, Konstantin Kostiuk wrote:
>         > On Thu, Jun 10, 2021 at 7:02 PM Daniel P. Berrangé
>         <berrange@redhat.com <mailto:berrange@redhat.com>>
>         > wrote:
>         >
>         > > On Thu, Jun 10, 2021 at 06:58:11PM +0300, Kostiantyn Kostiuk
>         wrote:
>         > > > The g_regex_match function creates match_info even if it
>         > > > returns FALSE. So we should always call g_match_info_free.
>         > > > A better solution is using g_autoptr for match_info variable.
>         > > >
>         > > > Signed-off-by: Kostiantyn Kostiuk <konstantin@daynix.com
>         <mailto:konstantin@daynix.com>>
>         > > > ---
>         > > >  qga/commands-win32.c | 3 +--
>         > > >  1 file changed, 1 insertion(+), 2 deletions(-)
>         > > >
>         > > > diff --git a/qga/commands-win32.c b/qga/commands-win32.c
>         > > > index 300b87c859..785a5cc6b2 100644
>         > > > --- a/qga/commands-win32.c
>         > > > +++ b/qga/commands-win32.c
>         > > > @@ -2494,7 +2494,7 @@ GuestDeviceInfoList
>         *qmp_guest_get_devices(Error
>         > > **errp)
>         > > >              continue;
>         > > >          }
>         > > >          for (j = 0; hw_ids[j] != NULL; j++) {
>         > > > -            GMatchInfo *match_info;
>         > > > +            g_autoptr(GMatchInfo) match_info;
>         > >
>         > > This should be initialized to NULL otherwise...
>         > >
>         > > >              GuestDeviceIdPCI *id;
>         > > >              if (!g_regex_match(device_pci_re, hw_ids[j], 0,
>         > > &match_info)) {
>         > > >                  continue;
>         > >
>         > > this continue will trigger freeing of unintialized memory
>         > >
>         >
>         > But we always call match_info, so match_info is always
>         initialized.
>         > The g_regex_match function creates match_info even if it
>         returns FALSE.
> 
>         Opps, yes, you are right.
> 
>         Reviewed-by: Daniel P. Berrangé <berrange@redhat.com
>         <mailto:berrange@redhat.com>>
> 
> 
>         Regards,
>         Daniel
>         -- 
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>         <https://www.instagram.com/dberrange> :|
>