diff mbox series

[v3] pinctrl: mediatek: Free eint data on failure

Message ID 20201001142511.3560143-1-enric.balletbo@collabora.com
State New
Headers show
Series [v3] pinctrl: mediatek: Free eint data on failure | expand

Commit Message

Enric Balletbo i Serra Oct. 1, 2020, 2:25 p.m. UTC
The pinctrl driver can work without the EINT resource, but, if it is
expected to have this resource but the mtk_build_eint() function fails
after allocating their data (because can't get the resource or can't map
the irq), the data is not freed and you end with a NULL pointer
dereference. Fix this by freeing the data if mtk_build_eint() fails, so
pinctrl still works and doesn't hang.

This is noticeable after commit f97dbf48ca43 ("irqchip/mtk-sysirq: Convert
to a platform driver") on MT8183 because, due this commit, the pinctrl driver
fails to map the irq and spots the following bug:

[    1.947597] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000004
[    1.956404] Mem abort info:
[    1.959203]   ESR = 0x96000004
[    1.962259]   EC = 0x25: DABT (current EL), IL = 32 bits
[    1.967565]   SET = 0, FnV = 0
[    1.970613]   EA = 0, S1PTW = 0
[    1.973747] Data abort info:
[    1.976619]   ISV = 0, ISS = 0x00000004
[    1.980447]   CM = 0, WnR = 0
[    1.983410] [0000000000000004] user address but active_mm is swapper
[    1.989759] Internal error: Oops: 96000004 [#1] PREEMPT SMP
[    1.995322] Modules linked in:
[    1.998371] CPU: 7 PID: 1 Comm: swapper/0 Not tainted 5.9.0-rc1+ #44
[    2.004715] Hardware name: MediaTek krane sku176 board (DT)
[    2.010280] pstate: 60000005 (nZCv daif -PAN -UAO BTYPE=--)
[    2.015850] pc : mtk_eint_set_debounce+0x48/0x1b8
[    2.020546] lr : mtk_eint_set_debounce+0x34/0x1b8
[    2.025239] sp : ffff80001008baa0
[    2.028544] x29: ffff80001008baa0 x28: ffff0000ff7ff790
[    2.033847] x27: ffff0000f9ec34b0 x26: ffff0000f9ec3480
[    2.039150] x25: ffff0000fa576410 x24: ffff0000fa502800
[    2.044453] x23: 0000000000001388 x22: ffff0000fa635f80
[    2.049755] x21: 0000000000000008 x20: 0000000000000000
[    2.055058] x19: 0000000000000071 x18: 0000000000000001
[    2.060360] x17: 0000000000000000 x16: 0000000000000000
[    2.065662] x15: ffff0000facc8470 x14: ffffffffffffffff
[    2.070965] x13: 0000000000000001 x12: 00000000000000c0
[    2.076267] x11: 0000000000000040 x10: 0000000000000070
[    2.081569] x9 : ffffaec0063d24d8 x8 : ffff0000fa800270
[    2.086872] x7 : 0000000000000000 x6 : 0000000000000011
[    2.092174] x5 : ffff0000fa800248 x4 : ffff0000fa800270
[    2.097476] x3 : ffff8000100c5000 x2 : 0000000000000000
[    2.102778] x1 : 0000000000000000 x0 : 0000000000000000
[    2.108081] Call trace:
[    2.110520]  mtk_eint_set_debounce+0x48/0x1b8
[    2.114870]  mtk_gpio_set_config+0x5c/0x78
[    2.118958]  gpiod_set_config+0x5c/0x78
[    2.122786]  gpiod_set_debounce+0x18/0x28
[    2.126789]  gpio_keys_probe+0x50c/0x910
[    2.130705]  platform_drv_probe+0x54/0xa8
[    2.134705]  really_probe+0xe4/0x3b0
[    2.138271]  driver_probe_device+0x58/0xb8
[    2.142358]  device_driver_attach+0x74/0x80
[    2.146532]  __driver_attach+0x58/0xe0
[    2.150274]  bus_for_each_dev+0x70/0xc0
[    2.154100]  driver_attach+0x24/0x30
[    2.157666]  bus_add_driver+0x14c/0x1f0
[    2.161493]  driver_register+0x64/0x120
[    2.165319]  __platform_driver_register+0x48/0x58
[    2.170017]  gpio_keys_init+0x1c/0x28
[    2.173672]  do_one_initcall+0x54/0x1b4
[    2.177499]  kernel_init_freeable+0x1d0/0x238
[    2.181848]  kernel_init+0x14/0x118
[    2.185328]  ret_from_fork+0x10/0x34
[    2.188899] Code: a9438ac1 12001266 f94006c3 121e766a (b9400421)
[    2.194991] ---[ end trace 168cf7b3324b6570 ]---
[    2.199611] Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b
[    2.207260] SMP: stopping secondary CPUs
[    2.211294] Kernel Offset: 0x2ebff4800000 from 0xffff800010000000
[    2.217377] PHYS_OFFSET: 0xffffb50500000000
[    2.221551] CPU features: 0x0240002,2188200c
[    2.225811] Memory Limit: none
[    2.228860] ---[ end Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b ]---

Fixes: 89132dd8ffd2 ("pinctrl: mediatek: extend eint build to pinctrl-mtk-common-v2.c")
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
---

Changes in v3:
- Really release the resource when needed. For some reason the change
  was not reflected in patch v2.

Changes in v2:
- Free the resource when needed (Sean Wang)

 .../pinctrl/mediatek/pinctrl-mtk-common-v2.c  | 29 ++++++++++++++-----
 1 file changed, 22 insertions(+), 7 deletions(-)

Comments

Sean Wang Oct. 2, 2020, 11:14 a.m. UTC | #1
On Thu, Oct 1, 2020 at 7:25 AM Enric Balletbo i Serra
<enric.balletbo@collabora.com> wrote:
>
> The pinctrl driver can work without the EINT resource, but, if it is
> expected to have this resource but the mtk_build_eint() function fails
> after allocating their data (because can't get the resource or can't map
> the irq), the data is not freed and you end with a NULL pointer
> dereference. Fix this by freeing the data if mtk_build_eint() fails, so
> pinctrl still works and doesn't hang.
>
> This is noticeable after commit f97dbf48ca43 ("irqchip/mtk-sysirq: Convert
> to a platform driver") on MT8183 because, due this commit, the pinctrl driver
> fails to map the irq and spots the following bug:
>
> [    1.947597] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000004
> [    1.956404] Mem abort info:
> [    1.959203]   ESR = 0x96000004
> [    1.962259]   EC = 0x25: DABT (current EL), IL = 32 bits
> [    1.967565]   SET = 0, FnV = 0
> [    1.970613]   EA = 0, S1PTW = 0
> [    1.973747] Data abort info:
> [    1.976619]   ISV = 0, ISS = 0x00000004
> [    1.980447]   CM = 0, WnR = 0
> [    1.983410] [0000000000000004] user address but active_mm is swapper
> [    1.989759] Internal error: Oops: 96000004 [#1] PREEMPT SMP
> [    1.995322] Modules linked in:
> [    1.998371] CPU: 7 PID: 1 Comm: swapper/0 Not tainted 5.9.0-rc1+ #44
> [    2.004715] Hardware name: MediaTek krane sku176 board (DT)
> [    2.010280] pstate: 60000005 (nZCv daif -PAN -UAO BTYPE=--)
> [    2.015850] pc : mtk_eint_set_debounce+0x48/0x1b8
> [    2.020546] lr : mtk_eint_set_debounce+0x34/0x1b8
> [    2.025239] sp : ffff80001008baa0
> [    2.028544] x29: ffff80001008baa0 x28: ffff0000ff7ff790
> [    2.033847] x27: ffff0000f9ec34b0 x26: ffff0000f9ec3480
> [    2.039150] x25: ffff0000fa576410 x24: ffff0000fa502800
> [    2.044453] x23: 0000000000001388 x22: ffff0000fa635f80
> [    2.049755] x21: 0000000000000008 x20: 0000000000000000
> [    2.055058] x19: 0000000000000071 x18: 0000000000000001
> [    2.060360] x17: 0000000000000000 x16: 0000000000000000
> [    2.065662] x15: ffff0000facc8470 x14: ffffffffffffffff
> [    2.070965] x13: 0000000000000001 x12: 00000000000000c0
> [    2.076267] x11: 0000000000000040 x10: 0000000000000070
> [    2.081569] x9 : ffffaec0063d24d8 x8 : ffff0000fa800270
> [    2.086872] x7 : 0000000000000000 x6 : 0000000000000011
> [    2.092174] x5 : ffff0000fa800248 x4 : ffff0000fa800270
> [    2.097476] x3 : ffff8000100c5000 x2 : 0000000000000000
> [    2.102778] x1 : 0000000000000000 x0 : 0000000000000000
> [    2.108081] Call trace:
> [    2.110520]  mtk_eint_set_debounce+0x48/0x1b8
> [    2.114870]  mtk_gpio_set_config+0x5c/0x78
> [    2.118958]  gpiod_set_config+0x5c/0x78
> [    2.122786]  gpiod_set_debounce+0x18/0x28
> [    2.126789]  gpio_keys_probe+0x50c/0x910
> [    2.130705]  platform_drv_probe+0x54/0xa8
> [    2.134705]  really_probe+0xe4/0x3b0
> [    2.138271]  driver_probe_device+0x58/0xb8
> [    2.142358]  device_driver_attach+0x74/0x80
> [    2.146532]  __driver_attach+0x58/0xe0
> [    2.150274]  bus_for_each_dev+0x70/0xc0
> [    2.154100]  driver_attach+0x24/0x30
> [    2.157666]  bus_add_driver+0x14c/0x1f0
> [    2.161493]  driver_register+0x64/0x120
> [    2.165319]  __platform_driver_register+0x48/0x58
> [    2.170017]  gpio_keys_init+0x1c/0x28
> [    2.173672]  do_one_initcall+0x54/0x1b4
> [    2.177499]  kernel_init_freeable+0x1d0/0x238
> [    2.181848]  kernel_init+0x14/0x118
> [    2.185328]  ret_from_fork+0x10/0x34
> [    2.188899] Code: a9438ac1 12001266 f94006c3 121e766a (b9400421)
> [    2.194991] ---[ end trace 168cf7b3324b6570 ]---
> [    2.199611] Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b
> [    2.207260] SMP: stopping secondary CPUs
> [    2.211294] Kernel Offset: 0x2ebff4800000 from 0xffff800010000000
> [    2.217377] PHYS_OFFSET: 0xffffb50500000000
> [    2.221551] CPU features: 0x0240002,2188200c
> [    2.225811] Memory Limit: none
> [    2.228860] ---[ end Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b ]---
>
> Fixes: 89132dd8ffd2 ("pinctrl: mediatek: extend eint build to pinctrl-mtk-common-v2.c")
> Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>

Acked-by: Sean Wang <sean.wang@kernel.org>

> ---
>
> Changes in v3:
> - Really release the resource when needed. For some reason the change
>   was not reflected in patch v2.
>
> Changes in v2:
> - Free the resource when needed (Sean Wang)
>
>  .../pinctrl/mediatek/pinctrl-mtk-common-v2.c  | 29 ++++++++++++++-----
>  1 file changed, 22 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.c b/drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.c
> index 2f3dfb56c3fa..31724b80f133 100644
> --- a/drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.c
> +++ b/drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.c
> @@ -355,6 +355,7 @@ int mtk_build_eint(struct mtk_pinctrl *hw, struct platform_device *pdev)
>  {
>         struct device_node *np = pdev->dev.of_node;
>         struct resource *res;
> +       int ret;
>
>         if (!IS_ENABLED(CONFIG_EINT_MTK))
>                 return 0;
> @@ -369,19 +370,26 @@ int mtk_build_eint(struct mtk_pinctrl *hw, struct platform_device *pdev)
>         res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "eint");
>         if (!res) {
>                 dev_err(&pdev->dev, "Unable to get eint resource\n");
> -               return -ENODEV;
> +               ret = -ENODEV;
> +               goto err_free_eint;
>         }
>
>         hw->eint->base = devm_ioremap_resource(&pdev->dev, res);
> -       if (IS_ERR(hw->eint->base))
> -               return PTR_ERR(hw->eint->base);
> +       if (IS_ERR(hw->eint->base)) {
> +               ret = PTR_ERR(hw->eint->base);
> +               goto err_free_eint;
> +       }
>
>         hw->eint->irq = irq_of_parse_and_map(np, 0);
> -       if (!hw->eint->irq)
> -               return -EINVAL;
> +       if (!hw->eint->irq) {
> +               ret = -EINVAL;
> +               goto err_release_resource;
> +       }
>
> -       if (!hw->soc->eint_hw)
> -               return -ENODEV;
> +       if (!hw->soc->eint_hw) {
> +               ret = -ENODEV;
> +               goto err_release_resource;
> +       }
>
>         hw->eint->dev = &pdev->dev;
>         hw->eint->hw = hw->soc->eint_hw;
> @@ -389,6 +397,13 @@ int mtk_build_eint(struct mtk_pinctrl *hw, struct platform_device *pdev)
>         hw->eint->gpio_xlate = &mtk_eint_xt;
>
>         return mtk_eint_do_init(hw->eint);
> +
> +err_release_resource:
> +       devm_ioremap_release(&pdev->dev, res);
> +err_free_eint:
> +       devm_kfree(hw->dev, hw->eint);
> +       hw->eint = NULL;
> +       return ret;
>  }
>  EXPORT_SYMBOL_GPL(mtk_build_eint);
>
> --
> 2.28.0
>
Linus Walleij Oct. 7, 2020, 8:33 a.m. UTC | #2
On Thu, Oct 1, 2020 at 4:25 PM Enric Balletbo i Serra
<enric.balletbo@collabora.com> wrote:

> The pinctrl driver can work without the EINT resource, but, if it is

> expected to have this resource but the mtk_build_eint() function fails

> after allocating their data (because can't get the resource or can't map

> the irq), the data is not freed and you end with a NULL pointer

> dereference. Fix this by freeing the data if mtk_build_eint() fails, so

> pinctrl still works and doesn't hang.


Patch applied after rebasing it. It wasn't entirely trivial so
check the result.

This will not apply on elder kernels and is now targeted for
v5.10. Fixes for v5.9 and stable will have to be backported once this
is upstream.

Yours,
Linus Walleij
diff mbox series

Patch

diff --git a/drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.c b/drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.c
index 2f3dfb56c3fa..31724b80f133 100644
--- a/drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.c
+++ b/drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.c
@@ -355,6 +355,7 @@  int mtk_build_eint(struct mtk_pinctrl *hw, struct platform_device *pdev)
 {
 	struct device_node *np = pdev->dev.of_node;
 	struct resource *res;
+	int ret;
 
 	if (!IS_ENABLED(CONFIG_EINT_MTK))
 		return 0;
@@ -369,19 +370,26 @@  int mtk_build_eint(struct mtk_pinctrl *hw, struct platform_device *pdev)
 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "eint");
 	if (!res) {
 		dev_err(&pdev->dev, "Unable to get eint resource\n");
-		return -ENODEV;
+		ret = -ENODEV;
+		goto err_free_eint;
 	}
 
 	hw->eint->base = devm_ioremap_resource(&pdev->dev, res);
-	if (IS_ERR(hw->eint->base))
-		return PTR_ERR(hw->eint->base);
+	if (IS_ERR(hw->eint->base)) {
+		ret = PTR_ERR(hw->eint->base);
+		goto err_free_eint;
+	}
 
 	hw->eint->irq = irq_of_parse_and_map(np, 0);
-	if (!hw->eint->irq)
-		return -EINVAL;
+	if (!hw->eint->irq) {
+		ret = -EINVAL;
+		goto err_release_resource;
+	}
 
-	if (!hw->soc->eint_hw)
-		return -ENODEV;
+	if (!hw->soc->eint_hw) {
+		ret = -ENODEV;
+		goto err_release_resource;
+	}
 
 	hw->eint->dev = &pdev->dev;
 	hw->eint->hw = hw->soc->eint_hw;
@@ -389,6 +397,13 @@  int mtk_build_eint(struct mtk_pinctrl *hw, struct platform_device *pdev)
 	hw->eint->gpio_xlate = &mtk_eint_xt;
 
 	return mtk_eint_do_init(hw->eint);
+
+err_release_resource:
+	devm_ioremap_release(&pdev->dev, res);
+err_free_eint:
+	devm_kfree(hw->dev, hw->eint);
+	hw->eint = NULL;
+	return ret;
 }
 EXPORT_SYMBOL_GPL(mtk_build_eint);