2019-03-14 05:57:23

by Kangjie Lu

[permalink] [raw]
Subject: [PATCH] pci: pcie-rcar: fix a potential NULL pointer dereference

In case __get_free_pages fails and returns NULL, the fix returns
-ENOMEM and releases resources to avoid NULL pointer dereference.

Signed-off-by: Kangjie Lu <[email protected]>
---
drivers/pci/controller/pcie-rcar.c | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/drivers/pci/controller/pcie-rcar.c b/drivers/pci/controller/pcie-rcar.c
index c8febb009454..0ba26c31d928 100644
--- a/drivers/pci/controller/pcie-rcar.c
+++ b/drivers/pci/controller/pcie-rcar.c
@@ -929,6 +929,12 @@ static int rcar_pcie_enable_msi(struct rcar_pcie *pcie)

/* setup MSI data target */
msi->pages = __get_free_pages(GFP_KERNEL, 0);
+ if (!msi->pages) {
+ dev_err(dev, "failed to get free pages\n");
+ err = -ENOMEM;
+ goto err;
+ }
+
base = virt_to_phys((void *)msi->pages);

rcar_pci_write_reg(pcie, base | MSIFE, PCIEMSIALR);
--
2.17.1



2019-03-14 07:31:20

by Geert Uytterhoeven

[permalink] [raw]
Subject: Re: [PATCH] pci: pcie-rcar: fix a potential NULL pointer dereference

Hi Kangjie,

On Thu, Mar 14, 2019 at 6:56 AM Kangjie Lu <[email protected]> wrote:
> In case __get_free_pages fails and returns NULL, the fix returns
> -ENOMEM and releases resources to avoid NULL pointer dereference.
>
> Signed-off-by: Kangjie Lu <[email protected]>

Thanks for your patch!

> --- a/drivers/pci/controller/pcie-rcar.c
> +++ b/drivers/pci/controller/pcie-rcar.c
> @@ -929,6 +929,12 @@ static int rcar_pcie_enable_msi(struct rcar_pcie *pcie)
>
> /* setup MSI data target */
> msi->pages = __get_free_pages(GFP_KERNEL, 0);
> + if (!msi->pages) {
> + dev_err(dev, "failed to get free pages\n");

Please drop the dev_err().
The memory allocation core will already have printed a warning, cfr.
warn_alloc() in mm/page_alloc.c.

With that fixed:
Reviewed-by: Geert Uytterhoeven <[email protected]>

> + err = -ENOMEM;
> + goto err;
> + }
> +

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds

2019-03-14 08:08:52

by Kangjie Lu

[permalink] [raw]
Subject: [PATCH v2] pci: pcie-rcar: fix a potential NULL pointer dereference

In case __get_free_pages fails and returns NULL, the fix returns
-ENOMEM and releases resources to avoid NULL pointer dereference.

Signed-off-by: Kangjie Lu <[email protected]>

---
V2 removes the error message.
---
drivers/pci/controller/pcie-rcar.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/pci/controller/pcie-rcar.c b/drivers/pci/controller/pcie-rcar.c
index c8febb009454..71e55995c058 100644
--- a/drivers/pci/controller/pcie-rcar.c
+++ b/drivers/pci/controller/pcie-rcar.c
@@ -929,6 +929,10 @@ static int rcar_pcie_enable_msi(struct rcar_pcie *pcie)

/* setup MSI data target */
msi->pages = __get_free_pages(GFP_KERNEL, 0);
+ if (!msi->pages) {
+ err = -ENOMEM;
+ goto err;
+ }
base = virt_to_phys((void *)msi->pages);

rcar_pci_write_reg(pcie, base | MSIFE, PCIEMSIALR);
--
2.17.1


2019-03-14 08:11:27

by Geert Uytterhoeven

[permalink] [raw]
Subject: Re: [PATCH v2] pci: pcie-rcar: fix a potential NULL pointer dereference

On Thu, Mar 14, 2019 at 9:08 AM Kangjie Lu <[email protected]> wrote:
> In case __get_free_pages fails and returns NULL, the fix returns
> -ENOMEM and releases resources to avoid NULL pointer dereference.
>
> Signed-off-by: Kangjie Lu <[email protected]>

Please keep my
Reviewed-by: Geert Uytterhoeven <[email protected]>

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds

2019-03-15 07:28:12

by Kangjie Lu

[permalink] [raw]
Subject: [PATCH v2] tty: atmel_serial: fix a NULL pointer dereference

Fixes: 34df42f59a60 ("serial: at91: add rx dma support")

In case dmaengine_prep_dma_cyclic fails, the fix returns a proper
error code to avoid NULL pointer dereference.

Signed-off-by: Kangjie Lu <[email protected]>

---
V2: simplified the patch as suggested by
Richard Genoud <[email protected]>
---
drivers/tty/serial/atmel_serial.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
index 05147fe24343..41b728d223d1 100644
--- a/drivers/tty/serial/atmel_serial.c
+++ b/drivers/tty/serial/atmel_serial.c
@@ -1288,6 +1288,10 @@ static int atmel_prepare_rx_dma(struct uart_port *port)
sg_dma_len(&atmel_port->sg_rx)/2,
DMA_DEV_TO_MEM,
DMA_PREP_INTERRUPT);
+ if (!desc) {
+ dev_err(port->dev, "Preparing DMA cyclic failed\n");
+ goto chan_err;
+ }
desc->callback = atmel_complete_rx_dma;
desc->callback_param = port;
atmel_port->desc_rx = desc;
--
2.17.1


2019-03-15 07:30:49

by Kangjie Lu

[permalink] [raw]
Subject: [PATCH v2] pci: pcie-rcar: fix a potential NULL pointer dereference

In case __get_free_pages fails and returns NULL, the fix returns
-ENOMEM and releases resources to avoid NULL pointer dereference.

Signed-off-by: Kangjie Lu <[email protected]>
Reviewed-by: Geert Uytterhoeven <[email protected]>

---
V2 removes the error message.
---
drivers/pci/controller/pcie-rcar.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/pci/controller/pcie-rcar.c b/drivers/pci/controller/pcie-rcar.c
index c8febb009454..71e55995c058 100644
--- a/drivers/pci/controller/pcie-rcar.c
+++ b/drivers/pci/controller/pcie-rcar.c
@@ -929,6 +929,10 @@ static int rcar_pcie_enable_msi(struct rcar_pcie *pcie)

/* setup MSI data target */
msi->pages = __get_free_pages(GFP_KERNEL, 0);
+ if (!msi->pages) {
+ err = -ENOMEM;
+ goto err;
+ }
base = virt_to_phys((void *)msi->pages);

rcar_pci_write_reg(pcie, base | MSIFE, PCIEMSIALR);
--
2.17.1


2019-03-15 08:24:31

by Richard Genoud

[permalink] [raw]
Subject: Re: [PATCH v2] tty: atmel_serial: fix a NULL pointer dereference

Le 15/03/2019 à 08:27, Kangjie Lu a écrit :
> Fixes: 34df42f59a60 ("serial: at91: add rx dma support")
The Fixes: tag should be just bellow the Signenf-off-by: tag
>
> In case dmaengine_prep_dma_cyclic fails, the fix returns a proper
> error code to avoid NULL pointer dereference.
>
> Signed-off-by: Kangjie Lu <[email protected]>
^^^
here
>
> ---
> V2: simplified the patch as suggested by
> Richard Genoud <[email protected]>
> ---
> drivers/tty/serial/atmel_serial.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
> index 05147fe24343..41b728d223d1 100644
> --- a/drivers/tty/serial/atmel_serial.c
> +++ b/drivers/tty/serial/atmel_serial.c
> @@ -1288,6 +1288,10 @@ static int atmel_prepare_rx_dma(struct uart_port *port)
> sg_dma_len(&atmel_port->sg_rx)/2,
> DMA_DEV_TO_MEM,
> DMA_PREP_INTERRUPT);
> + if (!desc) {
> + dev_err(port->dev, "Preparing DMA cyclic failed\n");
> + goto chan_err;
> + }
> desc->callback = atmel_complete_rx_dma;
> desc->callback_param = port;
> atmel_port->desc_rx = desc;
>

Thanks !

Richard.

2019-03-15 10:15:36

by Ulrich Hecht

[permalink] [raw]
Subject: Re: [PATCH v2] pci: pcie-rcar: fix a potential NULL pointer dereference


> On March 15, 2019 at 8:29 AM Kangjie Lu <[email protected]> wrote:
>
>
> In case __get_free_pages fails and returns NULL, the fix returns
> -ENOMEM and releases resources to avoid NULL pointer dereference.
>
> Signed-off-by: Kangjie Lu <[email protected]>
> Reviewed-by: Geert Uytterhoeven <[email protected]>

Reviewed-by: Ulrich Hecht <[email protected]>

CU
Uli

2019-03-15 11:56:22

by Simon Horman

[permalink] [raw]
Subject: Re: [PATCH v2] pci: pcie-rcar: fix a potential NULL pointer dereference

On Fri, Mar 15, 2019 at 02:29:43AM -0500, Kangjie Lu wrote:
> In case __get_free_pages fails and returns NULL, the fix returns
> -ENOMEM and releases resources to avoid NULL pointer dereference.
>
> Signed-off-by: Kangjie Lu <[email protected]>
> Reviewed-by: Geert Uytterhoeven <[email protected]>

Reviewed-by: Simon Horman <[email protected]>


2019-03-15 17:17:36

by Kangjie Lu

[permalink] [raw]
Subject: [PATCH] tty: atmel_serial: fix a NULL pointer dereference

In case dmaengine_prep_dma_cyclic fails, the fix returns a proper
error code to avoid NULL pointer dereference.

Signed-off-by: Kangjie Lu <[email protected]>
Fixes: 34df42f59a60 ("serial: at91: add rx dma support")

---
V2: simplified the patch as suggested by
Richard Genoud <[email protected]>
---
drivers/tty/serial/atmel_serial.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
index 05147fe24343..41b728d223d1 100644
--- a/drivers/tty/serial/atmel_serial.c
+++ b/drivers/tty/serial/atmel_serial.c
@@ -1288,6 +1288,10 @@ static int atmel_prepare_rx_dma(struct uart_port *port)
sg_dma_len(&atmel_port->sg_rx)/2,
DMA_DEV_TO_MEM,
DMA_PREP_INTERRUPT);
+ if (!desc) {
+ dev_err(port->dev, "Preparing DMA cyclic failed\n");
+ goto chan_err;
+ }
desc->callback = atmel_complete_rx_dma;
desc->callback_param = port;
atmel_port->desc_rx = desc;
--
2.17.1


2019-03-18 07:30:01

by Richard Genoud

[permalink] [raw]
Subject: Re: [PATCH] tty: atmel_serial: fix a NULL pointer dereference

Le 15/03/2019 à 18:16, Kangjie Lu a écrit :
> In case dmaengine_prep_dma_cyclic fails, the fix returns a proper
> error code to avoid NULL pointer dereference.
>
> Signed-off-by: Kangjie Lu <[email protected]>
> Fixes: 34df42f59a60 ("serial: at91: add rx dma support")
Acked-by: Richard Genoud <[email protected]>

>
> ---
> V2: simplified the patch as suggested by
> Richard Genoud <[email protected]>
> ---
> drivers/tty/serial/atmel_serial.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
> index 05147fe24343..41b728d223d1 100644
> --- a/drivers/tty/serial/atmel_serial.c
> +++ b/drivers/tty/serial/atmel_serial.c
> @@ -1288,6 +1288,10 @@ static int atmel_prepare_rx_dma(struct uart_port *port)
> sg_dma_len(&atmel_port->sg_rx)/2,
> DMA_DEV_TO_MEM,
> DMA_PREP_INTERRUPT);
> + if (!desc) {
> + dev_err(port->dev, "Preparing DMA cyclic failed\n");
> + goto chan_err;
> + }
> desc->callback = atmel_complete_rx_dma;
> desc->callback_param = port;
> atmel_port->desc_rx = desc;
>

Thanks !

Richard

2019-03-29 16:23:17

by Lorenzo Pieralisi

[permalink] [raw]
Subject: Re: [PATCH v2] pci: pcie-rcar: fix a potential NULL pointer dereference

On Fri, Mar 15, 2019 at 02:29:43AM -0500, Kangjie Lu wrote:
> In case __get_free_pages fails and returns NULL, the fix returns
> -ENOMEM and releases resources to avoid NULL pointer dereference.
>
> Signed-off-by: Kangjie Lu <[email protected]>
> Reviewed-by: Geert Uytterhoeven <[email protected]>
>
> ---
> V2 removes the error message.
> ---
> drivers/pci/controller/pcie-rcar.c | 4 ++++
> 1 file changed, 4 insertions(+)

Applied to pci/rcar for v5.2, thanks.

Lorenzo

> diff --git a/drivers/pci/controller/pcie-rcar.c b/drivers/pci/controller/pcie-rcar.c
> index c8febb009454..71e55995c058 100644
> --- a/drivers/pci/controller/pcie-rcar.c
> +++ b/drivers/pci/controller/pcie-rcar.c
> @@ -929,6 +929,10 @@ static int rcar_pcie_enable_msi(struct rcar_pcie *pcie)
>
> /* setup MSI data target */
> msi->pages = __get_free_pages(GFP_KERNEL, 0);
> + if (!msi->pages) {
> + err = -ENOMEM;
> + goto err;
> + }
> base = virt_to_phys((void *)msi->pages);
>
> rcar_pci_write_reg(pcie, base | MSIFE, PCIEMSIALR);
> --
> 2.17.1
>