From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 097A132B116; Thu, 30 Jul 2026 15:01:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785423690; cv=none; b=WCEY4q6kucz2LbdsUWC+bTkcySPMoXtcQ1778QtXi5QHezFp2OzFGtZkoFV4dgWEnGIJr8mV7ubWTbe00DO1jsCItsOCMgAvPJewgC7Z8UP8cAmVXc+cpHqALvhBxCDXoilbX7ww/BA/HIVknZkEcCM8bz04GRzGTwh1J83pOZI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785423690; c=relaxed/simple; bh=a/XR/seov+aTLCDBqkGAIGrsbM8wyZ6G1B4E39bRzR0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=DrZaqosJV5ELAn4bTh+m+Y9HBE18t04hQGprikI50aQPcCE1CqSxcb9+ScUTp0BnOIzrSJRz+kXca3v8LFB9gLXhYW6xoons5ew4e6P7PaxcBMj1NOYl5n4F9lPFkYs9Rw/kF1dsi98wVS7URbsWQPAwMZjz9DGomqsDPvPPLYI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=jRuc4G4f; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="jRuc4G4f" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 638911F000E9; Thu, 30 Jul 2026 15:01:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1785423688; bh=GHX/j9QTZJmuWNGleP2tJ9z2s4Rp2zt0gLjS5B2qSmc=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=jRuc4G4fiN5fuYZbz3PKFdHHlhQL2RchG9fa0u/Q/8f03vkaOb+9SrUlwFqQvyL9e 9swfNwSwHN6Jtydo6dzJHhcrGaYXdhUcj83FExufz3SUEF1eDq+HeCzlzvNf200cT8 f8nirpTEDk+g9LZ0cZ45U2caGEfKBHS+spYMmvbU= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Max Zhen , Lizhi Hou , Sasha Levin Subject: [PATCH 6.18 133/675] accel/amdxdna: Fix use-after-free of mm_struct in job scheduler Date: Thu, 30 Jul 2026 16:07:43 +0200 Message-ID: <20260730141447.969028808@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260730141445.110192266@linuxfoundation.org> References: <20260730141445.110192266@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Lizhi Hou [ Upstream commit faebb7ba1ac65fa5810b640df02ce04e509fdc11 ] amdxdna_cmd_submit() stores current->mm in job->mm without holding any reference. aie2_sched_job_run() later access job->mm from the DRM scheduler worker thread. With only a raw pointer and no structural reference, the mm_struct can be freed before the scheduler runs the job. Fix this by calling mmgrab() to hold a structural mm_count reference for the lifetime of the job, paired with mmdrop() in every cleanup path. Fixes: aac243092b70 ("accel/amdxdna: Add command execution") Reviewed-by: Max Zhen Signed-off-by: Lizhi Hou Link: https://patch.msgid.link/20260716151305.1595780-1-lizhi.hou@amd.com Signed-off-by: Sasha Levin --- drivers/accel/amdxdna/amdxdna_ctx.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/accel/amdxdna/amdxdna_ctx.c b/drivers/accel/amdxdna/amdxdna_ctx.c index cfee89681ff3cf..347e046d2a0fba 100644 --- a/drivers/accel/amdxdna/amdxdna_ctx.c +++ b/drivers/accel/amdxdna/amdxdna_ctx.c @@ -393,6 +393,7 @@ void amdxdna_sched_job_cleanup(struct amdxdna_sched_job *job) amdxdna_arg_bos_put(job); amdxdna_gem_put_obj(job->cmd_bo); dma_fence_put(job->fence); + mmdrop(job->mm); } int amdxdna_cmd_submit(struct amdxdna_client *client, @@ -443,6 +444,7 @@ int amdxdna_cmd_submit(struct amdxdna_client *client, job->hwctx = hwctx; job->mm = current->mm; + mmgrab(job->mm); job->fence = amdxdna_fence_create(hwctx); if (!job->fence) { @@ -475,6 +477,8 @@ int amdxdna_cmd_submit(struct amdxdna_client *client, cmd_put: amdxdna_gem_put_obj(job->cmd_bo); free_job: + if (job->mm) + mmdrop(job->mm); kfree(job); return ret; } -- 2.53.0