From patchwork Mon Mar 4 23:57:15 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bart Van Assche X-Patchwork-Id: 13581369 Received: from mail-pj1-f42.google.com (mail-pj1-f42.google.com [209.85.216.42]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 039CC7CF18; Mon, 4 Mar 2024 23:57:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.216.42 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709596666; cv=none; b=dtLM1RP6oh80urEdVpWnitSNmiWxZPlDGpxHIENBIBctsnEyu54FncSvQGmfsLhmZ1TM9yQSy7zO/kMadHQiRVsvq6HIcozrQec50/nwVULhAnvqdLFJzPe68VtH7gs7Q8mU61f5C+DyBV3O4dOtX3sJrUzqJsEBZVo0KGYiI3I= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709596666; c=relaxed/simple; bh=joY7OG7UIn3bqxbd1zB9uJBeqBt8fu89bKu/J05OF6g=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=JPvwfnhuFJBrNRhnIVHeZogvvAgW45yviUasU7q3QX1UPjAckJmDeL0aQhHdT5yW/ZZYUZcLW011BSu/h4/XGuYwRMN5PZp/PEAZyq6xlrQbZJpMMh5ayY5om3VuJTYEJlk8VDUUtEFbiMOkpgSHtc8QpaA3RFo90u8gPoWX7Us= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=acm.org; spf=pass smtp.mailfrom=gmail.com; arc=none smtp.client-ip=209.85.216.42 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=acm.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Received: by mail-pj1-f42.google.com with SMTP id 98e67ed59e1d1-29a378040daso3380517a91.1; Mon, 04 Mar 2024 15:57:44 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1709596664; x=1710201464; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=NNchAcLGNEoVQRiIQolT0ekrjSxf/xSsvda4T8WFAVg=; b=XEQEt84GUDOHbzyW8NpHABYnVFJ/KLqX/wuEzHq9jsfkbhqzb+c8V+G2eO6gFktr50 thbwlo4HmS5HYc4Z90LKLwsYUiS3cQOTQ4+9AyY79YTo0qsfEYS/x2saO9YVy6wcnJvy lTT4nPAwITrxI/QZlTTHAr+6eFYJ6VogkFlfX457R+3VtrTgiGUUnjgeiiC5SO9lDxOk EfKaITfvmMxtYp2SuNq7zohWA1fQi6H2FAUR0Mdv4oVtpGQGktaZnirA3nqzVqFy+GDz j8ujYB0Bho1Ra4zd4j3o7azejDVM/8wkl6JwRk9EuaWB5sSBGEcA3IpZKmBOisbEPhwd 6l/A== X-Forwarded-Encrypted: i=1; AJvYcCXtIPW2a3I5GR1YYzx8sZwFAn3jrFVq14LnkdpG6WT7PNgHeifpDLe1WVsRU0DHqCvumaRAqYVTANLrIwWz7PuClt2KHRmw X-Gm-Message-State: AOJu0YwksWasXXgXQ+WJOGLPDWUJzj5IpSZzer+gap/UbABb6Fwotfym G2YccKZNZq7y0OOZHE05CRp/0Wt/YMyP+rJH/hkFyDln2CsKM8qB X-Google-Smtp-Source: AGHT+IFTcbyAlas9hiaR2yPLZelINquCk/T2EmyChkVZIasuRGL+rZe9Tyc7IYgYR+fNxQp6beAOHA== X-Received: by 2002:a17:90b:4017:b0:29b:294c:831d with SMTP id ie23-20020a17090b401700b0029b294c831dmr8173282pjb.38.1709596664208; Mon, 04 Mar 2024 15:57:44 -0800 (PST) Received: from bvanassche-linux.mtv.corp.google.com ([2620:0:1000:8411:9ba8:35e8:4ec5:44d1]) by smtp.gmail.com with ESMTPSA id gb2-20020a17090b060200b0029acce2420asm8286417pjb.10.2024.03.04.15.57.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 04 Mar 2024 15:57:43 -0800 (PST) From: Bart Van Assche To: Christian Brauner Cc: linux-fsdevel@vger.kernel.org, Christoph Hellwig , Bart Van Assche , Eric Biggers , Benjamin LaHaise , Eric Biggers , Avi Kivity , Sandeep Dhavale , Jens Axboe , Greg Kroah-Hartman , Kent Overstreet , stable@vger.kernel.org Subject: [PATCH] fs/aio: Check IOCB_AIO_RW before the struct aio_kiocb conversion Date: Mon, 4 Mar 2024 15:57:15 -0800 Message-ID: <20240304235715.3790858-1-bvanassche@acm.org> X-Mailer: git-send-email 2.44.0.rc1.240.g4c46232300-goog Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 The first kiocb_set_cancel_fn() argument may point at a struct kiocb that is not embedded inside struct aio_kiocb. With the current code, depending on the compiler, the req->ki_ctx read happens either before the IOCB_AIO_RW test or after that test. Move the req->ki_ctx read such that it is guaranteed that the IOCB_AIO_RW test happens first. Reported-by: Eric Biggers Cc: Benjamin LaHaise Cc: Eric Biggers Cc: Christoph Hellwig Cc: Avi Kivity Cc: Sandeep Dhavale Cc: Jens Axboe Cc: Greg Kroah-Hartman Cc: Kent Overstreet Cc: stable@vger.kernel.org Fixes: b820de741ae4 ("fs/aio: Restrict kiocb_set_cancel_fn() to I/O submitted via libaio") Signed-off-by: Bart Van Assche Reviewed-by: Jens Axboe Reviewed-by: Eric Biggers --- fs/aio.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/fs/aio.c b/fs/aio.c index da18dbcfcb22..9cdaa2faa536 100644 --- a/fs/aio.c +++ b/fs/aio.c @@ -589,8 +589,8 @@ static int aio_setup_ring(struct kioctx *ctx, unsigned int nr_events) void kiocb_set_cancel_fn(struct kiocb *iocb, kiocb_cancel_fn *cancel) { - struct aio_kiocb *req = container_of(iocb, struct aio_kiocb, rw); - struct kioctx *ctx = req->ki_ctx; + struct aio_kiocb *req; + struct kioctx *ctx; unsigned long flags; /* @@ -600,9 +600,13 @@ void kiocb_set_cancel_fn(struct kiocb *iocb, kiocb_cancel_fn *cancel) if (!(iocb->ki_flags & IOCB_AIO_RW)) return; + req = container_of(iocb, struct aio_kiocb, rw); + if (WARN_ON_ONCE(!list_empty(&req->ki_list))) return; + ctx = req->ki_ctx; + spin_lock_irqsave(&ctx->ctx_lock, flags); list_add_tail(&req->ki_list, &ctx->active_reqs); req->ki_cancel = cancel;