From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793831513; b=4Ahlkm5bOxUbeKEgqRl0hff3DsgR5586RVdUdpuxTpvmf1IxYfg2/dwkvXyzTfRhCerj HcKpGY2Jnzp/H+8JF8zgdu7L1clmB2ybJKYjl6xZGtco8Mnqr7k2VOSgj+VpfBHg2oZH5 Tgs+Uxct5b87PoDBxRmnrtoz9ov+LvEeGk91YieMIT6s4a5xy6zFj7K6772R+QZLjmxM+ EEA/c1GruZ+4r7hW/J3C7LFfzAVSoLIsnhfP0pxplIS2aqlq8mXAQthKCIWsM3pwt5X+I D6lQ85LPekfo86Ju2LTEJXCqJw+ST2aMKRn+d4P9GEOWVlGumz1948Jxv6Qsivv7syw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793831513; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=2yvT6C0VmfZYhru2+QYk44sZl1fvZIs6EHms7zVrG2o=; b=AJwxpIBP62HOCN+WaFkdHRVjqz9caPFt/bCsDgONUgjUQCYCpD1qjiq7TZ3XJotShvQm v4FPseXJEvGdWsHg6l43BMSXIHaty+YOvAluQ5N43EMWEKfFQJkTh/iP44rt4mI9EfV3Y PAGIRcAiCOxvO9Ph0cRO4ZEM1rDhc6y7yDIkq/KwVydU7rs50L/3aM5KvG2UiIAwpoUSx Ynzp2EQeYpN3Pi8IgB2EMcJXjeOj5ApyV08Uq66+pSil3rfvEzMcoccJerJhnJeghrKpF 8UGK9Z8rCsXM/9sW61PqsIqkxadz+5e3CqG/QBDo/VlIPBTO9A4EJJ7hDTxeHS67xMg== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=erPTqSvb; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3B948606D80B; Wed, 4 Nov 2026 22:31:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=erPTqSvb Received: by smtp.kernel.org (Postfix) with ESMTPSA id C680C1F0093A; Wed, 4 Nov 2026 22:31:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1793831513; bh=2yvT6C0VmfZYhru2+QYk44sZl1fvZIs6EHms7zVrG2o=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=erPTqSvb3Ua2BI1KwZBbcFVAnYutD3//FXS+InKKfzLvDCaUQxy9qM2dXdgwajKGV CBuMYZhUrymw3w34/X8OrTmMMO+DymtfuDABlz3PMX68eL0cxPvKcUtqpfXuT0BUTo 0B5RCu2rwSpfzqzStS9zVlzuMjx21KWr9AZbUhps= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Sean Young , Hans Verkuil Subject: [PATCH 6.18 0748/1005] media: rc: Use after free in ir_raw_event_handle() Date: Wed, 4 Nov 2026 16:08:01 -0500 Message-ID: <20261104211104.412807527@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261104211043.516122098@linuxfoundation.org> References: <20261104211043.516122098@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: patches@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sean Young commit 3ae19773168104fa57d2a2ec57731e89df54175f upstream. If rc_unregister_device() is called while IR is being processed, then ir_raw_event_handle() could call wake_up_process(dev->raw->thread) after kthread_stop(dev->raw->thread). Avoid use after free by using get_task_struct(). Fixes: dccc0c3ddf8f ("media: rc: fix race between unregister and urb/irq callbacks") Signed-off-by: Sean Young Cc: stable@vger.kernel.org Reviewed-by: Hans Verkuil Signed-off-by: Greg Kroah-Hartman --- drivers/media/rc/rc-ir-raw.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) --- a/drivers/media/rc/rc-ir-raw.c +++ b/drivers/media/rc/rc-ir-raw.c @@ -648,8 +648,13 @@ int ir_raw_event_register(struct rc_dev void ir_raw_event_free(struct rc_dev *dev) { - kfree(dev->raw); - dev->raw = NULL; + if (dev->raw) { + timer_delete_sync(&dev->raw->edge_handle); + if (dev->raw->thread) + put_task_struct(dev->raw->thread); + kfree(dev->raw); + dev->raw = NULL; + } } void ir_raw_event_unregister(struct rc_dev *dev) @@ -659,6 +664,13 @@ void ir_raw_event_unregister(struct rc_d if (!dev || !dev->raw) return; + /* + * After ir_raw_event_unregister() is called, an sync + * call to ir_raw_event_handle() can still arrive. This function + * may call wake_up_process(dev->raw->thread). Ensure this memory + * is not freed by kthread_stop(). + */ + get_task_struct(dev->raw->thread); kthread_stop(dev->raw->thread); timer_delete_sync(&dev->raw->edge_handle);