From nobody Fri Oct 2 04:35:50 2026 Received: from zg8tmtyylji0my4xnjeumjiw.icoremail.net (zg8tmtyylji0my4xnjeumjiw.icoremail.net [162.243.161.220]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 323D83F410F; Wed, 5 Aug 2026 09:09:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=162.243.161.220 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785920983; cv=none; b=GhGLQ8RMyTB3hRrq5YqzBKMmsOg0yg0ZvAXoY9h8DgIgE7xq6NWQBqVRVYX5yt06yqdC80bZdx1CXLrwRc7/qLPcVuMOF1lb8hFg+AjbKixJzTGqVCwIzB1RE7Vbe0UUTqpGWOJ7NH+s32ET6LoP+KS2q737195JTHmEHn6JZX8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785920983; c=relaxed/simple; bh=9UaMQIIzDep4GFF4WTqr+2+cJAOj/WBb56I8DIyVQhQ=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=Oeq6oRV9jsmHVQDiGGJx98m270JtyE8vmljZdr+Q3Rzhh8s5o5A+ya4HuFuUi5VlKr5et138s9Hd6pzrzsFLjKLFUrwZSh2U7TKzxT/V1qyd/bJlZXOdNKhKM2AC93Q565ShqQoZOaQNdbYP/gYt85qiONtU+oiukOrA7C4MXfQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=zju.edu.cn; spf=pass smtp.mailfrom=zju.edu.cn; arc=none smtp.client-ip=162.243.161.220 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=zju.edu.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=zju.edu.cn Received: from zju.edu.cn (unknown [10.98.66.117]) by mtasvr (Coremail) with SMTP id _____wCnvnys_XJqQsFoAA--.23227S3; Wed, 05 Aug 2026 17:09:01 +0800 (CST) Received: from localhost.localdomain (unknown [10.98.66.117]) by mail-app3 (Coremail) with SMTP id zS_KCgD3DnGr_XJqMPv5Aw--.15483S2; Wed, 05 Aug 2026 17:08:59 +0800 (CST) From: Fan Wu To: dri-devel@lists.freedesktop.org Cc: Andrzej Hajda , Neil Armstrong , Robert Foss , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Marek Vasut , linux-kernel@vger.kernel.org, stable@vger.kernel.org, Fan Wu Subject: [PATCH] drm/bridge: ti-sn65dsi83: Cancel reset_work on remove to avoid use-after-free Date: Wed, 5 Aug 2026 09:08:04 +0000 Message-Id: <20260805090804.78914-1-fanwu01@zju.edu.cn> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: zS_KCgD3DnGr_XJqMPv5Aw--.15483S2 X-CM-SenderInfo: qrstjiaswqq6lmxovvfxof0/ X-CM-DELIVERINFO: =?B?9RKe2QXKKxbFmtjJiESix3B1w3vZ3A9ovKVTomAyoQazvoRs/NHSP8GI2EvgeEEW7R sfnZPoDCNGYdHSfuFmYJL54WMBzwIw6lQvkaUf6bwSXuEgIb5CSQ0Hx1t1bgLLzQ5Dx51z 1w49cJTUDgdKWAabouHN5RPxYw6l01w8CbPzC/8w X-Coremail-Antispam: 1Uk129KBj93XoW7uw48urWfCF4DWw17tFy8Xrc_yoW8ur4fpF WftryYkrWkXFWj9aykAF18XFy5Cw1ktayFkryUGw4fu345XFWYy3sYkFWYgFyakr1UAa4a yr4vyrWUZFy2y3XCm3ZEXasCq-sJn29KB7ZKAUJUUUUU529EdanIXcx71UUUUU7KY7ZEXa sCq-sGcSsGvfJ3Ic02F40EFcxC0VAKzVAqx4xG6I80ebIjqfuFe4nvWSU5nxnvy29KBjDU 0xBIdaVrnRJUUUP0b4IE77IF4wAFF20E14v26r4j6ryUM7CY07I20VC2zVCF04k26cxKx2 IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48v e4kI8wA2z4x0Y4vE2Ix0cI8IcVAFwI0_tr0E3s1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI 0_Gr1j6F4UJwA2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AK xVW0oVCq3wAac4AC62xK8xCEY4vEwIxC4wAS0I0E0xvYzxvE52x082IY62kv0487Mc804V CY07AIYIkI8VC2zVCFFI0UMc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0I7IYx2IY67AK xVWUJVWUGwAv7VC2z280aVAFwI0_Gr0_Cr1lOx8S6xCaFVCjc4AY6r1j6r4UM4x0Y48Icx kI7VAKI48JM4x0Y48IcxkI7VAKI48G6xCjnVAKz4kxM4IIrI8v6xkF7I0E8cxan2IY04v7 MxAIw28IcxkI7VAKI48JMxC20s026xCaFVCjc4AY6r1j6r4UMI8I3I0E5I8CrVAFwI0_Jr 0_Jr4lx2IqxVCjr7xvwVAFwI0_JrI_JrWlx4CE17CEb7AF67AKxVW8ZVWrXwCIc40Y0x0E wIxGrwCI42IY6xIIjxv20xvE14v26r1j6r1xMIIF0xvE2Ix0cI8IcVCY1x0267AKxVW8JV WxJwCI42IY6xAIw20EY4v20xvaj40_Jr0_JF4lIxAIcVC2z280aVAFwI0_Gr0_Cr1lIxAI cVC2z280aVCY1x0267AKxVW8JVW8JrUvcSsGvfC2KfnxnUUI43ZEXa7IU86c_DUUUUU== Content-Type: text/plain; charset="utf-8" The error recovery code queues ctx->reset_work from the threaded IRQ handler and the polling monitor_work, but nothing ever cancels it. sn65dsi83_remove() only unplugs the bridge, and the sn65dsi83_release_resources devm action disables the IRQ at the chip and stops monitor_work but does not cancel reset_work. The IRQ is devm-managed, so a reset_work already queued survives detach and the devm IRQ free and runs after ctx is freed, recovering it via container_of() and leading to a use-after-free. drm_bridge_enter()/SRCU guards a running work against bridge removal but cannot stop a queued work running after ctx is gone. Stop the producers before unplug, then drain: disable_irq so the threaded handler can no longer queue reset_work, cancel monitor_work, then cancel_work_sync(&ctx->reset_work). disable_irq keeps the IRQ registered so a racing reset_work's trailing enable_irq() stays valid, while its disable depth stops the handler from re-arming before ctx is freed. This issue was found by an in-house static analysis tool. Compile-tested only; runtime testing is appreciated. Fixes: ad5c6ecef27e ("drm: bridge: ti-sn65dsi83: Add error recovery mechani= sm") Cc: stable@vger.kernel.org Assisted-by: Codex:gpt-5.6 Signed-off-by: Fan Wu --- drivers/gpu/drm/bridge/ti-sn65dsi83.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/gpu/drm/bridge/ti-sn65dsi83.c b/drivers/gpu/drm/bridge= /ti-sn65dsi83.c index 42b451432bbb..d334b2898e25 100644 --- a/drivers/gpu/drm/bridge/ti-sn65dsi83.c +++ b/drivers/gpu/drm/bridge/ti-sn65dsi83.c @@ -1069,6 +1069,12 @@ static void sn65dsi83_remove(struct i2c_client *clie= nt) { struct sn65dsi83 *ctx =3D i2c_get_clientdata(client); =20 + /* Stop the reset_work producers, then drain, before unplug. */ + if (ctx->irq) + disable_irq(ctx->irq); + cancel_delayed_work_sync(&ctx->monitor_work); + cancel_work_sync(&ctx->reset_work); + drm_bridge_unplug(&ctx->bridge); } =20 --=20 2.39.5