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 DC94C34250D for ; Sat, 28 Feb 2026 18:03:54 +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=1772301834; cv=none; b=iaCwGpIy1cBv3d/2T2nN1C4S1Lf5+VHrTNAUtYPZutjiBBzFoMGxPXtNzyUAMhJRPt4mL71rJ0ARkamK/utV+AOknd4xwgVekLsMUkpOGneNv7BJD9N1EyYJEO/9o7IAIHSvpvJ6c3frNXPu6RC2vURZlTaF+5Js4Gn6P6nu3ng= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772301834; c=relaxed/simple; bh=N13wIcIMWbXHMXWO02qwysTNALPzf9timKH7iOtw0w0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=tolst8p4P3n9TUq7RrcY1g4FB25EOo9dAH+52Eerjf3UXRUPgbuudhnusFs1GV2nzYhXI7ZpO2X5mSnL09wYCIue1seoYYCzqtT508/JYb1R2Ga+dAoubLuQuPa2UqBLhB2N+xdB+W0N2NfPBFR21ZaHeAcM6T5nq5h0YkszqQo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=RpR+vfgN; 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="RpR+vfgN" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4E638C116D0; Sat, 28 Feb 2026 18:03:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772301834; bh=N13wIcIMWbXHMXWO02qwysTNALPzf9timKH7iOtw0w0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=RpR+vfgNAjEYCRlxd4h2fsF/RcHjop5SpI4a+5rffUzdU+iE1OSfAGNG3iOBApLAu EjXKxaY9kQ/nT5iCMo78ulRMvt6+SSEV+rO0onWGh//BMx4esPclYmlX2N3p2jdchj E3u8kLMX8r1hiLdvrzcXluBAYtv0qiM5USYTFYawlsmVMpCxjsMKQDa5OLe0Pf6u2X PPuUzL33eOQimdz57cxF+ieODJKHqTZWpDabcmFYHrjXZogIyd8PUuvY1HWey2qBVH JS5QU3hRq8fXesHweYQ8JAXJFtw6IVnJ5rZX2My+oXHFtl05YF65n8KGmax7FVaPo8 YuLp0qmGzcrSA== From: Sasha Levin To: patches@lists.linux.dev Cc: Waqar Hameed , Sebastian Reichel , Sasha Levin Subject: [PATCH 6.12 252/385] power: supply: bq256xx: Fix use-after-free in power_supply_changed() Date: Sat, 28 Feb 2026 12:57:54 -0500 Message-ID: <20260228180011.1568201-252-sashal@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260228180011.1568201-1-sashal@kernel.org> References: <20260228180011.1568201-1-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 5514d1896bb84..b47b73ed642e5 100644 --- a/drivers/power/supply/bq256xx_charger.c +++ b/drivers/power/supply/bq256xx_charger.c @@ -1741,6 +1741,12 @@ 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, @@ -1753,12 +1759,6 @@ 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