From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D445138D017 for ; Sat, 28 Feb 2026 18:09:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772302177; cv=none; b=EpetLr7Q5U7n8oa7y65kiNMGH8DXDXEOPcEA3UC+hbrNv88DVqGiPWiMgiOUO4XEfSpq38xPqZvk3llh+scEeG1rvYF0xvTBO11be0O7NNzY5qO5i6EnUIYTTKf0mpJtALOzxNeUb1Q6hDh2zIoxGADQniSsGjxsPX2lsEdSl3Y= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772302177; c=relaxed/simple; bh=XS7yCkPaoW2IEsg4gRh6jYV2eyPp/1gD2vs+glAbB/M=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=CsPD1OIerL4mud7UpobLQPScazIEhe3V9PC7gy5Ufte3lZHMV0J6k3A2ulXqvWJ0m/kUu0gc6x9eZUd2DHTqOdXzm6PT8PgBiAJDddgJttp52xTeqXz6ABZkYP53lrgMw1fR2/A2j09Mpa0wdPrtN6jK2nvQm68RJhNLoXJONNg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=pGD/RcjC; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="pGD/RcjC" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2F847C19424; Sat, 28 Feb 2026 18:09:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772302177; bh=XS7yCkPaoW2IEsg4gRh6jYV2eyPp/1gD2vs+glAbB/M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pGD/RcjCmoaPVHBR7M+EN8NY1YfkHZxEzTowp6EdXkOhBgV5CZ5vSfBZLctWuDd49 D1eSWCx86jXueswfidHl+BvarcrTn9IUyy/sYBs6sCcRLHndIdrMsOSvJmdG0GKBf1 Dp3OA2RWY/GBwWe0yRBsk8q90KcooLZGRmeyBREMakpSGNEdnNzUXVjYdBznqluyPx 10mhBhoaZYbmOVPJFUPkqetN+JMZU4rJxFCRkdPJcWb7KwQ3gLpPpJtG4dpnw/qDp0 ivqYjWBbCYyvetRov6LhnLB9x3heWxIA3jksSzisQLC59gkThuIKU6nRJBl2Mo0Adc f/Qs2HKMdupJA== From: Sasha Levin To: patches@lists.linux.dev Cc: Waqar Hameed , Phil Reid , Sebastian Reichel , Sasha Levin Subject: [PATCH 6.6 177/283] power: supply: sbs-battery: Fix use-after-free in power_supply_changed() Date: Sat, 28 Feb 2026 13:05:19 -0500 Message-ID: <20260228180709.1583486-177-sashal@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260228180709.1583486-1-sashal@kernel.org> References: <20260228180709.1583486-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit From: Waqar Hameed [ Upstream commit 8d59cf3887fbabacef53bfba473e33e8a8d9d07b ] 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. Keep the old behavior of just printing a warning in case of any failures during the IRQ request and finishing the probe successfully. Fixes: d2cec82c2880 ("power: sbs-battery: Request threaded irq and fix dev callback cookie") Signed-off-by: Waqar Hameed Reviewed-by: Phil Reid Link: https://patch.msgid.link/0ef896e002495e615157b482d18a437af19ddcd0.1766268280.git.waqar.hameed@axis.com Signed-off-by: Sebastian Reichel Signed-off-by: Sasha Levin --- drivers/power/supply/sbs-battery.c | 36 +++++++++++++++--------------- 1 file changed, 18 insertions(+), 18 deletions(-) diff --git a/drivers/power/supply/sbs-battery.c b/drivers/power/supply/sbs-battery.c index cdfc8466d129b..f30a542d4716c 100644 --- a/drivers/power/supply/sbs-battery.c +++ b/drivers/power/supply/sbs-battery.c @@ -1173,24 +1173,6 @@ static int sbs_probe(struct i2c_client *client) i2c_set_clientdata(client, chip); - if (!chip->gpio_detect) - goto skip_gpio; - - irq = gpiod_to_irq(chip->gpio_detect); - if (irq <= 0) { - dev_warn(&client->dev, "Failed to get gpio as irq: %d\n", irq); - goto skip_gpio; - } - - rc = devm_request_threaded_irq(&client->dev, irq, NULL, sbs_irq, - IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING | IRQF_ONESHOT, - dev_name(&client->dev), chip); - if (rc) { - dev_warn(&client->dev, "Failed to request irq: %d\n", rc); - goto skip_gpio; - } - -skip_gpio: /* * Before we register, we might need to make sure we can actually talk * to the battery. @@ -1216,6 +1198,24 @@ static int sbs_probe(struct i2c_client *client) return dev_err_probe(&client->dev, PTR_ERR(chip->power_supply), "Failed to register power supply\n"); + if (!chip->gpio_detect) + goto out; + + irq = gpiod_to_irq(chip->gpio_detect); + if (irq <= 0) { + dev_warn(&client->dev, "Failed to get gpio as irq: %d\n", irq); + goto out; + } + + rc = devm_request_threaded_irq(&client->dev, irq, NULL, sbs_irq, + IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING | IRQF_ONESHOT, + dev_name(&client->dev), chip); + if (rc) { + dev_warn(&client->dev, "Failed to request irq: %d\n", rc); + goto out; + } + +out: dev_info(&client->dev, "%s: battery gas gauge device registered\n", client->name); -- 2.51.0