[PATCH 6.6.y 2/2] gpio: rockchip: fix generic IRQ chip leak on remove

[Artem Dinaburg <artem@trailofbits.com>]

From: Marco Scardovi <scardracs@disroot.org>

[ Upstream commit 1c1e0fc88d6ef65bf15d517853251f75ab9d18c3 ]

The driver allocates domain generic chips using
irq_alloc_domain_generic_chips() during probe. However, on driver
remove/teardown, the generic chips are not automatically freed when the
IRQ domain is removed because the domain flags do not include
IRQ_DOMAIN_FLAG_DESTROY_GC.

This causes both the domain generic chips structure and the associated
generic chips to be leaked. Additionally, the generic chips remain on
the global gc_list and may later be visited by generic IRQ chip suspend,
resume, or shutdown callbacks after the GPIO bank has been removed,
potentially resulting in a use-after-free and kernel crash.

Fix the resource leak by explicitly calling
irq_domain_remove_generic_chips() before removing the IRQ domain in
rockchip_gpio_remove().

[ Backport to 6.6.y: Use the upstream teardown helper on 6.6. Defer 6.1
  because irq_domain_remove_generic_chips() is absent and needs a
  prerequisite or reviewed target-native cleanup. ]

Fixes: 936ee2675eee ("gpio/rockchip: add driver for rockchip gpio")
Assisted-by: Antigravity:gemini-3.5-flash
Signed-off-by: Marco Scardovi <scardracs@disroot.org>
Link: https://patch.msgid.link/20260607230504.35392-2-scardracs@disroot.org
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Assisted-by: LLM
Signed-off-by: Artem Dinaburg <artem@trailofbits.com>
---
This is patch 2 of 2 in the ordered 6.6.y backport series.
This change addresses CVE-2026-53226. The target creates generic IRQ chips
and omits their removal; the prerequisite supplies a complete teardown
helper and the CVE fix invokes it before removing the IRQ domain.

The fix is already present in 6.12.y, 6.18.y, and 7.2.y, but not in 6.6.y.

 drivers/gpio/gpio-rockchip.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/gpio/gpio-rockchip.c b/drivers/gpio/gpio-rockchip.c
index e0e4f3ed5fdd..86cf3cbcdb40 100644
--- a/drivers/gpio/gpio-rockchip.c
+++ b/drivers/gpio/gpio-rockchip.c
@@ -786,8 +786,10 @@ static int rockchip_gpio_remove(struct platform_device *pdev)
 	struct rockchip_pin_bank *bank = platform_get_drvdata(pdev);
 
 	irq_set_chained_handler_and_data(bank->irq, NULL, NULL);
-	if (bank->domain)
+	if (bank->domain) {
+		irq_domain_remove_generic_chips(bank->domain);
 		irq_domain_remove(bank->domain);
+	}
 	gpiochip_remove(&bank->gpio_chip);
 
 	return 0;
-- 
2.39.5