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 0C62A33A6F2 for ; Sat, 28 Feb 2026 18:09:34 +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=1772302174; cv=none; b=TdO4yBlq3ch1pplBAI1ih/OTpGsUNNoTNeFDdOvR7kbXPIgkfSMqTmGiZZuX6SG5GCzbtoALlCAk5XoSxAKSXMG5cSm4ZTBxzqqtCXmgWFlaqNLhi1pgl9+GEliy3PLYxIIc82P/YJ54OYxnI95BIA7oUMJKdsykTcsXQVOmR24= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772302174; c=relaxed/simple; bh=Fx383WXRDsEaQLyejXTWxBuHv1ZL978lLNW4c797m0E=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=a7whZSPy+fK2sMBXH6Ef7BPfatrHjk8n4/aCkfMMTwMtwbDGzFFo5aOzHdYLIDgYSSyUVQvl8C77ClPeet6zLGelN703M6nFLQZKk9NuPX8p4ovaSIansRZ2ANrdQAxQLN6k27XdTSqsTHbagNQ+Br5XZoJMctTJKfGoTDHdNnU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=XSX1ZMVS; 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="XSX1ZMVS" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 712A2C19423; Sat, 28 Feb 2026 18:09:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772302173; bh=Fx383WXRDsEaQLyejXTWxBuHv1ZL978lLNW4c797m0E=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=XSX1ZMVSbWkKTDIrF0rvQjmB13rt66SNg/u+ySg5hKL2B/vYVDSLPfzLlUbVgsZ4d 56e0d7egmsRDwPTcnFBlKp04qPlaNT1IhDT71RzqcxntUnUFIVhIJcbgZwEd3MrZyR Pjh1yFP32+4LIkXpIO9I49UB7ScjUEMGH7Iop4MCWFeZPSxXB/Pw9rpSgN+sn0FBbZ BrawoQD7aOIdeKgZnx/yxRETdhFIR/U3Pov5T0Oxfsqt7DCQa4FWrHe2XnJI9CGiXn xuVypPxbUMHLc2kcLrSZSuZe0EYo9yY0knWNXTikSr4dpK/UEhrRlPcIDru2rbIYgY 34NmufDMSaAXA== From: Sasha Levin To: patches@lists.linux.dev Cc: Waqar Hameed , Sebastian Reichel , Sasha Levin Subject: [PATCH 6.6 172/283] power: supply: bq256xx: Fix use-after-free in power_supply_changed() Date: Sat, 28 Feb 2026 13:05:14 -0500 Message-ID: <20260228180709.1583486-172-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 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 c8368dae69c71..2b0216d32d5f7 100644 --- a/drivers/power/supply/bq256xx_charger.c +++ b/drivers/power/supply/bq256xx_charger.c @@ -1746,6 +1746,12 @@ 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, @@ -1758,12 +1764,6 @@ 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