diff options
| author | Waqar Hameed <waqar.hameed@axis.com> | 2025-12-21 01:36:01 +0300 |
|---|---|---|
| committer | Sebastian Reichel <sebastian.reichel@collabora.com> | 2026-01-12 04:52:30 +0300 |
| commit | 838767f5074700552d3f006d867caed65edc7328 (patch) | |
| tree | 09f38de02f6f4f22715fbc3f6d3b712f33b2d9b6 | |
| parent | b2ce982e2e0c888dc55c888ad0e20ea04daf2e6b (diff) | |
| download | linux-838767f5074700552d3f006d867caed65edc7328.tar.xz | |
power: supply: pf1550: Fix use-after-free in power_supply_changed()
Using the `devm_` variant for requesting IRQ _before_ the `devm_`
variant for allocating/registering the `power_supply` handle, means that
the `power_supply` 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 `power_supply`
handle has been freed, *but* just _before_ the corresponding
unregistration of the IRQ handler has run.
This will lead to the IRQ handler calling `power_supply_changed()` with
a freed `power_supply` handle. Which usually crashes the system or
otherwise silently corrupts the memory...
Note that there is a similar situation which can also happen during
`probe()`; the possibility of an interrupt firing _before_ registering
the `power_supply` handle. This would then lead to the nasty situation
of using the `power_supply` handle *uninitialized* in
`power_supply_changed()`.
Fix this racy use-after-free by making sure the IRQ is requested _after_
the registration of the `power_supply` handle.
Fixes: 4b6b6433a97d ("power: supply: pf1550: add battery charger support")
Signed-off-by: Waqar Hameed <waqar.hameed@axis.com>
Reviewed-by: Samuel Kayode <samkay014@gmail.com>
Link: https://patch.msgid.link/ae5a71b7e4dd2967d8fdcc531065cc71b17c86f5.1766268280.git.waqar.hameed@axis.com
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
| -rw-r--r-- | drivers/power/supply/pf1550-charger.c | 32 |
1 files changed, 16 insertions, 16 deletions
diff --git a/drivers/power/supply/pf1550-charger.c b/drivers/power/supply/pf1550-charger.c index 98f1ee8eca3b..a457862ef461 100644 --- a/drivers/power/supply/pf1550-charger.c +++ b/drivers/power/supply/pf1550-charger.c @@ -584,22 +584,6 @@ static int pf1550_charger_probe(struct platform_device *pdev) return dev_err_probe(chg->dev, ret, "failed to add battery sense work\n"); - for (i = 0; i < PF1550_CHARGER_IRQ_NR; i++) { - irq = platform_get_irq(pdev, i); - if (irq < 0) - return irq; - - chg->virqs[i] = irq; - - ret = devm_request_threaded_irq(&pdev->dev, irq, NULL, - pf1550_charger_irq_handler, - IRQF_NO_SUSPEND, - "pf1550-charger", chg); - if (ret) - return dev_err_probe(&pdev->dev, ret, - "failed irq request\n"); - } - psy_cfg.drv_data = chg; chg->charger = devm_power_supply_register(&pdev->dev, @@ -616,6 +600,22 @@ static int pf1550_charger_probe(struct platform_device *pdev) return dev_err_probe(&pdev->dev, PTR_ERR(chg->battery), "failed: power supply register\n"); + for (i = 0; i < PF1550_CHARGER_IRQ_NR; i++) { + irq = platform_get_irq(pdev, i); + if (irq < 0) + return irq; + + chg->virqs[i] = irq; + + ret = devm_request_threaded_irq(&pdev->dev, irq, NULL, + pf1550_charger_irq_handler, + IRQF_NO_SUSPEND, + "pf1550-charger", chg); + if (ret) + return dev_err_probe(&pdev->dev, ret, + "failed irq request\n"); + } + pf1550_dt_parse_dev_info(chg); return pf1550_reg_init(chg); |