diff options
| author | Waqar Hameed <waqar.hameed@axis.com> | 2025-12-20 23:35:59 +0100 |
|---|---|---|
| committer | Sebastian Reichel <sebastian.reichel@collabora.com> | 2026-01-12 02:52:29 +0100 |
| commit | 5f0b1cb41906e86b64bf69f5ededb83b0d757c27 (patch) | |
| tree | 758d91b3679398de214c2bcbd9fc63c6d4fb6475 /drivers/power/supply | |
| parent | 8005843369723d9c8975b7c4202d1b85d6125302 (diff) | |
power: supply: bq25980: 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: 5069185fc18e ("power: supply: bq25980: Add support for the BQ259xx family")
Signed-off-by: Waqar Hameed <waqar.hameed@axis.com>
Link: https://patch.msgid.link/8763035cadb959e14787b3837f2d3db61f6e1c34.1766268280.git.waqar.hameed@axis.com
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Diffstat (limited to 'drivers/power/supply')
| -rw-r--r-- | drivers/power/supply/bq25980_charger.c | 12 |
1 files changed, 6 insertions, 6 deletions
diff --git a/drivers/power/supply/bq25980_charger.c b/drivers/power/supply/bq25980_charger.c index 4f91fd1a3dec..44af3a0c92e5 100644 --- a/drivers/power/supply/bq25980_charger.c +++ b/drivers/power/supply/bq25980_charger.c @@ -1240,6 +1240,12 @@ static int bq25980_probe(struct i2c_client *client) return ret; } + ret = bq25980_power_supply_init(bq, dev); + if (ret) { + dev_err(dev, "Failed to register power supply\n"); + return ret; + } + if (client->irq) { ret = devm_request_threaded_irq(dev, client->irq, NULL, bq25980_irq_handler_thread, @@ -1250,12 +1256,6 @@ static int bq25980_probe(struct i2c_client *client) return ret; } - ret = bq25980_power_supply_init(bq, dev); - if (ret) { - dev_err(dev, "Failed to register power supply\n"); - return ret; - } - ret = bq25980_hw_init(bq); if (ret) { dev_err(dev, "Cannot initialize the chip.\n"); |