diff mbox series

[v3,7/9] vdpa: solidrun: Fix UB bug with devres

Message ID 20240822134744.44919-8-pstanner@redhat.com
State New
Headers show
Series PCI: Remove pcim_iounmap_regions() | expand

Commit Message

Philipp Stanner Aug. 22, 2024, 1:47 p.m. UTC
In psnet_open_pf_bar() and snet_open_vf_bar() a string later passed to
pcim_iomap_regions() is placed on the stack. Neither
pcim_iomap_regions() nor the functions it calls copy that string.

Should the string later ever be used, this, consequently, causes
undefined behavior since the stack frame will by then have disappeared.

Fix the bug by allocating the strings on the heap through
devm_kasprintf().

Cc: stable@vger.kernel.org	# v6.3
Fixes: 51a8f9d7f587 ("virtio: vdpa: new SolidNET DPU driver.")
Reported-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Closes: https://lore.kernel.org/all/74e9109a-ac59-49e2-9b1d-d825c9c9f891@wanadoo.fr/
Suggested-by: Andy Shevchenko <andy@kernel.org>
Signed-off-by: Philipp Stanner <pstanner@redhat.com>
---
 drivers/vdpa/solidrun/snet_main.c | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

Comments

Christophe JAILLET Aug. 22, 2024, 2:34 p.m. UTC | #1
Le 22/08/2024 à 15:47, Philipp Stanner a écrit :
> In psnet_open_pf_bar() and snet_open_vf_bar() a string later passed to
> pcim_iomap_regions() is placed on the stack. Neither
> pcim_iomap_regions() nor the functions it calls copy that string.
> 
> Should the string later ever be used, this, consequently, causes
> undefined behavior since the stack frame will by then have disappeared.
> 
> Fix the bug by allocating the strings on the heap through
> devm_kasprintf().
> 
> Cc: stable@vger.kernel.org	# v6.3
> Fixes: 51a8f9d7f587 ("virtio: vdpa: new SolidNET DPU driver.")
> Reported-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
> Closes: https://lore.kernel.org/all/74e9109a-ac59-49e2-9b1d-d825c9c9f891@wanadoo.fr/
> Suggested-by: Andy Shevchenko <andy@kernel.org>
> Signed-off-by: Philipp Stanner <pstanner@redhat.com>
> ---
>   drivers/vdpa/solidrun/snet_main.c | 13 +++++++++----
>   1 file changed, 9 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/vdpa/solidrun/snet_main.c b/drivers/vdpa/solidrun/snet_main.c
> index 99428a04068d..67235f6190ef 100644
> --- a/drivers/vdpa/solidrun/snet_main.c
> +++ b/drivers/vdpa/solidrun/snet_main.c
> @@ -555,7 +555,7 @@ static const struct vdpa_config_ops snet_config_ops = {
>   
>   static int psnet_open_pf_bar(struct pci_dev *pdev, struct psnet *psnet)
>   {
> -	char name[50];
> +	char *name;
>   	int ret, i, mask = 0;
>   	/* We don't know which BAR will be used to communicate..
>   	 * We will map every bar with len > 0.
> @@ -573,7 +573,10 @@ static int psnet_open_pf_bar(struct pci_dev *pdev, struct psnet *psnet)
>   		return -ENODEV;
>   	}
>   
> -	snprintf(name, sizeof(name), "psnet[%s]-bars", pci_name(pdev));
> +	name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "psnet[%s]-bars", pci_name(pdev));
> +	if (!name)
> +		return -ENOMEM;
> +
>   	ret = pcim_iomap_regions(pdev, mask, name);
>   	if (ret) {
>   		SNET_ERR(pdev, "Failed to request and map PCI BARs\n");
> @@ -590,10 +593,12 @@ static int psnet_open_pf_bar(struct pci_dev *pdev, struct psnet *psnet)
>   
>   static int snet_open_vf_bar(struct pci_dev *pdev, struct snet *snet)
>   {
> -	char name[50];
> +	char *name;
>   	int ret;
>   
> -	snprintf(name, sizeof(name), "snet[%s]-bar", pci_name(pdev));
> +	name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "psnet[%s]-bars", pci_name(pdev));

s/psnet/snet/

> +	if (!name)
> +		return -ENOMEM;
>   	/* Request and map BAR */
>   	ret = pcim_iomap_regions(pdev, BIT(snet->psnet->cfg.vf_bar), name);
>   	if (ret) {
Andy Shevchenko Aug. 22, 2024, 2:47 p.m. UTC | #2
On Thu, Aug 22, 2024 at 03:47:39PM +0200, Philipp Stanner wrote:
> In psnet_open_pf_bar() and snet_open_vf_bar() a string later passed to
> pcim_iomap_regions() is placed on the stack. Neither
> pcim_iomap_regions() nor the functions it calls copy that string.
> 
> Should the string later ever be used, this, consequently, causes
> undefined behavior since the stack frame will by then have disappeared.
> 
> Fix the bug by allocating the strings on the heap through
> devm_kasprintf().

...

> -	snprintf(name, sizeof(name), "psnet[%s]-bars", pci_name(pdev));
> +	name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "psnet[%s]-bars", pci_name(pdev));
> +	if (!name)
> +		return -ENOMEM;
> +
>  	ret = pcim_iomap_regions(pdev, mask, name);

...

> -	snprintf(name, sizeof(name), "snet[%s]-bar", pci_name(pdev));
> +	name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "psnet[%s]-bars", pci_name(pdev));
> +	if (!name)
> +		return -ENOMEM;

+ Blank line as in the above snippet?

>  	/* Request and map BAR */
>  	ret = pcim_iomap_regions(pdev, BIT(snet->psnet->cfg.vf_bar), name);
Philipp Stanner Aug. 26, 2024, 6:55 a.m. UTC | #3
On Thu, 2024-08-22 at 16:34 +0200, Christophe JAILLET wrote:
> Le 22/08/2024 à 15:47, Philipp Stanner a écrit :
> > In psnet_open_pf_bar() and snet_open_vf_bar() a string later passed
> > to
> > pcim_iomap_regions() is placed on the stack. Neither
> > pcim_iomap_regions() nor the functions it calls copy that string.
> > 
> > Should the string later ever be used, this, consequently, causes
> > undefined behavior since the stack frame will by then have
> > disappeared.
> > 
> > Fix the bug by allocating the strings on the heap through
> > devm_kasprintf().
> > 
> > Cc: stable@vger.kernel.org	# v6.3
> > Fixes: 51a8f9d7f587 ("virtio: vdpa: new SolidNET DPU driver.")
> > Reported-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
> > Closes:
> > https://lore.kernel.org/all/74e9109a-ac59-49e2-9b1d-d825c9c9f891@wanadoo.fr/
> > Suggested-by: Andy Shevchenko <andy@kernel.org>
> > Signed-off-by: Philipp Stanner <pstanner@redhat.com>
> > ---
> >   drivers/vdpa/solidrun/snet_main.c | 13 +++++++++----
> >   1 file changed, 9 insertions(+), 4 deletions(-)
> > 
> > diff --git a/drivers/vdpa/solidrun/snet_main.c
> > b/drivers/vdpa/solidrun/snet_main.c
> > index 99428a04068d..67235f6190ef 100644
> > --- a/drivers/vdpa/solidrun/snet_main.c
> > +++ b/drivers/vdpa/solidrun/snet_main.c
> > @@ -555,7 +555,7 @@ static const struct vdpa_config_ops
> > snet_config_ops = {
> >   
> >   static int psnet_open_pf_bar(struct pci_dev *pdev, struct psnet
> > *psnet)
> >   {
> > -	char name[50];
> > +	char *name;
> >   	int ret, i, mask = 0;
> >   	/* We don't know which BAR will be used to communicate..
> >   	 * We will map every bar with len > 0.
> > @@ -573,7 +573,10 @@ static int psnet_open_pf_bar(struct pci_dev
> > *pdev, struct psnet *psnet)
> >   		return -ENODEV;
> >   	}
> >   
> > -	snprintf(name, sizeof(name), "psnet[%s]-bars",
> > pci_name(pdev));
> > +	name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "psnet[%s]-
> > bars", pci_name(pdev));
> > +	if (!name)
> > +		return -ENOMEM;
> > +
> >   	ret = pcim_iomap_regions(pdev, mask, name);
> >   	if (ret) {
> >   		SNET_ERR(pdev, "Failed to request and map PCI
> > BARs\n");
> > @@ -590,10 +593,12 @@ static int psnet_open_pf_bar(struct pci_dev
> > *pdev, struct psnet *psnet)
> >   
> >   static int snet_open_vf_bar(struct pci_dev *pdev, struct snet
> > *snet)
> >   {
> > -	char name[50];
> > +	char *name;
> >   	int ret;
> >   
> > -	snprintf(name, sizeof(name), "snet[%s]-bar",
> > pci_name(pdev));
> > +	name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "psnet[%s]-
> > bars", pci_name(pdev));
> 
> s/psnet/snet/

sharp eyes ;)

Thx,
P.

> 
> > +	if (!name)
> > +		return -ENOMEM;
> >   	/* Request and map BAR */
> >   	ret = pcim_iomap_regions(pdev, BIT(snet->psnet-
> > >cfg.vf_bar), name);
> >   	if (ret) {
>
diff mbox series

Patch

diff --git a/drivers/vdpa/solidrun/snet_main.c b/drivers/vdpa/solidrun/snet_main.c
index 99428a04068d..67235f6190ef 100644
--- a/drivers/vdpa/solidrun/snet_main.c
+++ b/drivers/vdpa/solidrun/snet_main.c
@@ -555,7 +555,7 @@  static const struct vdpa_config_ops snet_config_ops = {
 
 static int psnet_open_pf_bar(struct pci_dev *pdev, struct psnet *psnet)
 {
-	char name[50];
+	char *name;
 	int ret, i, mask = 0;
 	/* We don't know which BAR will be used to communicate..
 	 * We will map every bar with len > 0.
@@ -573,7 +573,10 @@  static int psnet_open_pf_bar(struct pci_dev *pdev, struct psnet *psnet)
 		return -ENODEV;
 	}
 
-	snprintf(name, sizeof(name), "psnet[%s]-bars", pci_name(pdev));
+	name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "psnet[%s]-bars", pci_name(pdev));
+	if (!name)
+		return -ENOMEM;
+
 	ret = pcim_iomap_regions(pdev, mask, name);
 	if (ret) {
 		SNET_ERR(pdev, "Failed to request and map PCI BARs\n");
@@ -590,10 +593,12 @@  static int psnet_open_pf_bar(struct pci_dev *pdev, struct psnet *psnet)
 
 static int snet_open_vf_bar(struct pci_dev *pdev, struct snet *snet)
 {
-	char name[50];
+	char *name;
 	int ret;
 
-	snprintf(name, sizeof(name), "snet[%s]-bar", pci_name(pdev));
+	name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "psnet[%s]-bars", pci_name(pdev));
+	if (!name)
+		return -ENOMEM;
 	/* Request and map BAR */
 	ret = pcim_iomap_regions(pdev, BIT(snet->psnet->cfg.vf_bar), name);
 	if (ret) {