From: Waqar Hameed Date: Fri, 23 Jan 2026 10:24:20 +0000 (+0100) Subject: power: supply: pm8916_lbc: Fix use-after-free for extcon in IRQ handler X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=23067259919663580c6f81801847cfc7bd54fd1f;p=thirdparty%2Fkernel%2Flinux.git power: supply: pm8916_lbc: Fix use-after-free for extcon in IRQ handler Using the `devm_` variant for requesting IRQ _before_ the `devm_` variant for allocating/registering the `extcon` handle, means that the `extcon` handle will be deallocated/unregistered _before_ the interrupt handler (since `devm_` naturally deallocates in reverse allocation order). This means that during removal, there is a race condition where an interrupt can fire just _after_ the `extcon` handle has been freed, *but* just _before_ the corresponding unregistration of the IRQ handler has run. This will lead to the IRQ handler calling `extcon_set_state_sync()` with a freed `extcon` handle. Which usually crashes the system or otherwise silently corrupts the memory... Fix this racy use-after-free by making sure the IRQ is requested _after_ the registration of the `extcon` handle. Fixes: f8d7a3d21160 ("power: supply: Add driver for pm8916 lbc") Signed-off-by: Waqar Hameed Reviewed-by: Nikita Travkin Link: https://patch.msgid.link/e2a4cd2fcd42b6cd97d856c17c097289a2aed393.1769163273.git.waqar.hameed@axis.com Signed-off-by: Sebastian Reichel --- diff --git a/drivers/power/supply/pm8916_lbc.c b/drivers/power/supply/pm8916_lbc.c index 3ca717d84aade..6b631012a7959 100644 --- a/drivers/power/supply/pm8916_lbc.c +++ b/drivers/power/supply/pm8916_lbc.c @@ -327,11 +327,6 @@ static int pm8916_lbc_charger_probe(struct platform_device *pdev) if (irq < 0) return irq; - ret = devm_request_threaded_irq(dev, irq, NULL, pm8916_lbc_charger_state_changed_irq, - IRQF_ONESHOT, "pm8916_lbc", chg); - if (ret) - return ret; - chg->edev = devm_extcon_dev_allocate(dev, pm8916_lbc_charger_cable); if (IS_ERR(chg->edev)) return PTR_ERR(chg->edev); @@ -340,6 +335,11 @@ static int pm8916_lbc_charger_probe(struct platform_device *pdev) if (ret < 0) return dev_err_probe(dev, ret, "failed to register extcon device\n"); + ret = devm_request_threaded_irq(dev, irq, NULL, pm8916_lbc_charger_state_changed_irq, + IRQF_ONESHOT, "pm8916_lbc", chg); + if (ret) + return ret; + ret = regmap_read(chg->regmap, chg->reg[LBC_USB] + PM8916_INT_RT_STS, &tmp); if (ret) goto comm_error;