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 6EC7339B946 for ; Sat, 28 Feb 2026 18:16:28 +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=1772302588; cv=none; b=VR+sdpYK9FrUddSeflcgcOdxeyWyGnD5IwWYeBfCYc+V00Qn6FVOze+5iEcAJVhx4+lS5gZXX2N7StqwAwJYFAXM/7X0X/+ModgSSPyH2IqEnLzbt3Nohf2hYctH3zcKWxLj+2CX4iS5rgKEfuAjpkGnipkC2lnx+aR6LZ8IVIc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772302588; c=relaxed/simple; bh=8eRuyXHr+ZczlnLyciYvq4zUC5x8fDvCGABhq1H9Oi0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=UpXjHvw1hHWsbXX3pg2WA1uH1otlYnibPTLP1XjbzFUM57pvv0XAxUwWKNfQPpj3LTLHrxiTK2sdraoHgyecRac4FmYwsY8sA8gn8iECc2P5jagFHTN8Cztq45H0RZj5SsGQSwZv3mAmZL0KcZ7lzJAvP/REZzd6CtZr8rQg5nc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=qWaP4T7V; 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="qWaP4T7V" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D0098C19424; Sat, 28 Feb 2026 18:16:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772302588; bh=8eRuyXHr+ZczlnLyciYvq4zUC5x8fDvCGABhq1H9Oi0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qWaP4T7VeArY4cacWZbKxjVZ7Ko85m+g5CDO8gVCcPfKdp/LZ8f4xdK1SriduhM6+ 71dCJH1vKMJvs4lh/rhEEFW62HgiKR+8Vnix+SyIRKYr1DysC2es6Fzo3iZSrbI7Pi i+j8XnWUUDiKJwjhEbsQrGstD3K2dPwUfjvOl7TohA4dWgyVrVbnYheoYFCtCqfKym MUBBOqByhU8o6QVeDwHCq7HNwNtJ78OuKngvdrSpdh/2fF3GS/RxsASdW55eZTxbQW c+AdarJ8u2xprOYzCDDclP7lTp3Lz2nPJyUO09rHEW1f2sRmx/VQc9QtT7SVQ4Lr7Z DKapdmQ07LLXw== From: Sasha Levin To: patches@lists.linux.dev Cc: Waqar Hameed , Sebastian Reichel , Sasha Levin Subject: [PATCH 5.15 098/164] power: supply: bq256xx: Fix use-after-free in power_supply_changed() Date: Sat, 28 Feb 2026 13:13:57 -0500 Message-ID: <20260228181505.1600663-98-sashal@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260228181505.1600663-1-sashal@kernel.org> References: <20260228181505.1600663-1-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 8005843369723d9c8975b7c4202d1b85d6125302 ] 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: 32e4978bb920 ("power: supply: bq256xx: Introduce the BQ256XX charger driver") Signed-off-by: Waqar Hameed Link: https://patch.msgid.link/39da6da8cc060fa0382ca859f65071e791cb6119.1766268280.git.waqar.hameed@axis.com Signed-off-by: Sebastian Reichel Signed-off-by: Sasha Levin --- drivers/power/supply/bq256xx_charger.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/drivers/power/supply/bq256xx_charger.c b/drivers/power/supply/bq256xx_charger.c index 9fb7b44e890af..86f8ce4035209 100644 --- a/drivers/power/supply/bq256xx_charger.c +++ b/drivers/power/supply/bq256xx_charger.c @@ -1675,6 +1675,12 @@ static int bq256xx_probe(struct i2c_client *client, usb_register_notifier(bq->usb3_phy, &bq->usb_nb); } + ret = bq256xx_power_supply_init(bq, &psy_cfg, 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, bq256xx_irq_handler_thread, @@ -1687,12 +1693,6 @@ static int bq256xx_probe(struct i2c_client *client, } } - ret = bq256xx_power_supply_init(bq, &psy_cfg, dev); - if (ret) { - dev_err(dev, "Failed to register power supply\n"); - return ret; - } - ret = bq256xx_hw_init(bq); if (ret) { dev_err(dev, "Cannot initialize the chip.\n"); -- 2.51.0