[PATCH 5.10 058/120] gpiolib: free device name on error path to fix kmemleak

Greg Kroah-Hartman
2021-02-08T17:12:22Z

From: Quanyang Wang <quanyang.wang@windriver.com>

commit c351bb64cbe67029c68dea3adbec1b9508c6ff0f upstream.

In gpiochip_add_data_with_key, we should check the return value of
dev_set_name to ensure that device name is allocated successfully
and then add a label on the error path to free device name to fix
kmemleak as below:

unreferenced object 0xc2d6fc40 (size 64):
comm "kworker/0:1", pid 16, jiffies 4294937425 (age 65.120s)
hex dump (first 32 bytes):
67 70 69 6f 63 68 69 70 30 00 1a c0 54 63 1a c0 gpiochip0...Tc..
0c ed 84 c0 48 ed 84 c0 3c ee 84 c0 10 00 00 00 ....H...<.......
backtrace:
[<962810f7>] kobject_set_name_vargs+0x2c/0xa0
[<f50797e6>] dev_set_name+0x2c/0x5c
[<94abbca9>] gpiochip_add_data_with_key+0xfc/0xce8
[<5c4193e0>] omap_gpio_probe+0x33c/0x68c
[<3402f137>] platform_probe+0x58/0xb8
[<7421e210>] really_probe+0xec/0x3b4
[<000f8ada>] driver_probe_device+0x58/0xb4
[<67e0f7f7>] bus_for_each_drv+0x80/0xd0
[<4de545dc>] __device_attach+0xe8/0x15c
[<2e4431e7>] bus_probe_device+0x84/0x8c
[<c18b1de9>] device_add+0x384/0x7c0
[<5aff2995>] of_platform_device_create_pdata+0x8c/0xb8
[<061c3483>] of_platform_bus_create+0x198/0x230
[<5ee6d42a>] of_platform_populate+0x60/0xb8
[<2647300f>] sysc_probe+0xd18/0x135c
[<3402f137>] platform_probe+0x58/0xb8

Signed-off-by: Quanyang Wang <quanyang.wang@windriver.com>
Cc: stable@vger.kernel.org
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/gpio/gpiolib.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)

--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -602,7 +602,11 @@ int gpiochip_add_data_with_key(struct gp
ret = gdev->id;
goto err_free_gdev;
}
- dev_set_name(&gdev->dev, GPIOCHIP_NAME "%d", gdev->id);
+
+ ret = dev_set_name(&gdev->dev, GPIOCHIP_NAME "%d", gdev->id);
+ if (ret)
+ goto err_free_ida;
+
device_initialize(&gdev->dev);
dev_set_drvdata(&gdev->dev, gdev);
if (gc->parent && gc->parent->driver)
@@ -616,7 +620,7 @@ int gpiochip_add_data_with_key(struct gp
gdev->descs = kcalloc(gc->ngpio, sizeof(gdev->descs[0]), GFP_KERNEL);
if (!gdev->descs) {
ret = -ENOMEM;
- goto err_free_ida;
+ goto err_free_dev_name;
}

if (gc->ngpio == 0) {
@@ -767,6 +771,8 @@ err_free_label:
kfree_const(gdev->label);
err_free_descs:
kfree(gdev->descs);
+err_free_dev_name:
+ kfree(dev_name(&gdev->dev));
err_free_ida:
ida_free(&gpio_ida, gdev->id);