From patchwork Thu Oct 6 13:25:05 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: "Jason A. Donenfeld" X-Patchwork-Id: 13000325 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2A988C38A05 for ; Thu, 6 Oct 2022 13:26:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230255AbiJFNZ6 (ORCPT ); Thu, 6 Oct 2022 09:25:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33644 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230111AbiJFNZx (ORCPT ); Thu, 6 Oct 2022 09:25:53 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 59E68A8CDD; Thu, 6 Oct 2022 06:25:52 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id CDEDE6199F; Thu, 6 Oct 2022 13:25:51 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B6A38C433D6; Thu, 6 Oct 2022 13:25:46 +0000 (UTC) Authentication-Results: smtp.kernel.org; dkim=pass (1024-bit key) header.d=zx2c4.com header.i=@zx2c4.com header.b="U19BJ3bB" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=zx2c4.com; s=20210105; t=1665062745; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=7dFj46iv6B3wpMLAkzxu2+UZUtW66eQt4bdRtLsdjWc=; b=U19BJ3bBONmCvTPAh8uyTTfbJMDEIORNPRa/gw0p0oqINVUGtieIgpXVc1s6oQT1xpTUGu EKtfsElTXyRWuUz+KDHImGkvljaIMeDpXlV/PnfxnGCQYNTmUia1TE+L96QKJjYd8/6F35 8Pc27xLTY3BvRaGlSceTp3zdkfZHO+0= Received: by mail.zx2c4.com (ZX2C4 Mail Server) with ESMTPSA id b30e7dab (TLSv1.3:TLS_AES_256_GCM_SHA384:256:NO); Thu, 6 Oct 2022 13:25:44 +0000 (UTC) From: "Jason A. Donenfeld" To: linux-kernel@vger.kernel.org, patches@lists.linux.dev Cc: "Jason A. Donenfeld" , Andreas Noever , Andrew Morton , Andy Shevchenko , Borislav Petkov , =?utf-8?q?Christoph_B=C3=B6hmwalder?= , Christoph Hellwig , Daniel Borkmann , Dave Airlie , Dave Hansen , "David S . Miller" , Eric Dumazet , Florian Westphal , Greg Kroah-Hartman , "H . Peter Anvin" , Herbert Xu , Hugh Dickins , Jakub Kicinski , "James E . J . Bottomley" , Jan Kara , Jason Gunthorpe , Jens Axboe , Johannes Berg , Jonathan Corbet , Jozsef Kadlecsik , KP Singh , Kees Cook , Marco Elver , Mauro Carvalho Chehab , Michael Ellerman , Pablo Neira Ayuso , Paolo Abeni , Theodore Ts'o , Thomas Gleixner , Thomas Graf , Ulf Hansson , Vignesh Raghavendra , Yury Norov , dri-devel@lists.freedesktop.org, kasan-dev@googlegroups.com, kernel-janitors@vger.kernel.org, linux-block@vger.kernel.org, linux-crypto@vger.kernel.org, linux-doc@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-media@vger.kernel.org, linux-mm@kvack.org, linux-mmc@vger.kernel.org, linux-mtd@lists.infradead.org, linux-nvme@lists.infradead.org, linux-rdma@vger.kernel.org, linux-usb@vger.kernel.org, linux-wireless@vger.kernel.org, netdev@vger.kernel.org Subject: [PATCH v2 0/5] treewide cleanup of random integer usage Date: Thu, 6 Oct 2022 07:25:05 -0600 Message-Id: <20221006132510.23374-1-Jason@zx2c4.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org [Posting v2 right away, because I CC'd too many people for v1, and email systems worldwide exploded.] Hi folks, This is a five part treewide cleanup of random integer handling. The rules for random integers are: - If you want a secure or an insecure random u64, use get_random_u64(). - If you want a secure or an insecure random u32, use get_random_u32(). * The old function prandom_u32() has been deprecated for a while now and is just a wrapper around get_random_u32(). - If you want a secure or an insecure random u16, use get_random_u16(). - If you want a secure or an insecure random u8, use get_random_u8(). - If you want secure or insecure random bytes, use get_random_bytes(). * The old function prandom_bytes() has been deprecated for a while now and has long been a wrapper around get_random_bytes(). - If you want a non-uniform random u32, u16, or u8 bounded by a certain open interval maximum, use prandom_u32_max(). * I say "non-uniform", because it doesn't do any rejection sampling or divisions. Hence, it stays within the prandom_* namespace. These rules ought to be applied uniformly, so that we can clean up the deprecated functions, and earn the benefits of using the modern functions. In particular, in addition to the boring substitutions, this patchset accomplishes a few nice effects: - By using prandom_u32_max() with an upper-bound that the compiler can prove at compile-time is ≤65536 or ≤256, internally get_random_u16() or get_random_u8() is used, which wastes fewer batched random bytes, and hence has higher throughput. - By using prandom_u32_max() instead of %, when the upper-bound is not a constant, division is still avoided, because prandom_u32_max() uses a faster multiplication-based trick instead. - By using get_random_u16() or get_random_u8() in cases where the return value is intended to indeed be a u16 or a u8, we waste fewer batched random bytes, and hence have higher throughput. So, based on those rules and benefits from following them, this patchset breaks down into the following five steps, which were done mostly manually: 1) Replace `prandom_u32() % max` and variants thereof with prandom_u32_max(max). 2) Replace `(type)get_random_u32()` and variants thereof with get_random_u16() or get_random_u8(). I took the pains to actually look and see what every lvalue type was across the entire tree. 3) Replace remaining deprecated uses of prandom_u32() with get_random_u32(). 4) Replace remaining deprecated uses of prandom_bytes() with get_random_bytes(). 5) Remove the deprecated and now-unused prandom_u32() and prandom_bytes() inline wrapper functions. I was thinking of taking this through my random.git tree (on which this series is currently based) and submitting it near the end of the merge window, or waiting for the very end of the 6.1 cycle when there will be the fewest new patches brewing. If somebody with some treewide-cleanup experience might share some wisdom about what the best timing usually winds up being, I'm all ears. Please take a look! Thanks, Jason Cc: Andreas Noever Cc: Andrew Morton Cc: Andy Shevchenko Cc: Borislav Petkov Cc: Christoph Böhmwalder Cc: Christoph Hellwig Cc: Daniel Borkmann Cc: Dave Airlie Cc: Dave Hansen Cc: David S. Miller Cc: Eric Dumazet Cc: Florian Westphal Cc: Greg Kroah-Hartman , Cc: H. Peter Anvin Cc: Herbert Xu Cc: Hugh Dickins Cc: Jakub Kicinski Cc: James E.J. Bottomley Cc: Jan Kara Cc: Jason Gunthorpe Cc: Jens Axboe Cc: Johannes Berg Cc: Jonathan Corbet Cc: Jozsef Kadlecsik Cc: KP Singh Cc: Kees Cook Cc: Marco Elver Cc: Mauro Carvalho Chehab Cc: Michael Ellerman Cc: Pablo Neira Ayuso Cc: Paolo Abeni Cc: Theodore Ts'o Cc: Thomas Gleixner Cc: Thomas Graf Cc: Ulf Hansson Cc: Vignesh Raghavendra Cc: Yury Norov Cc: dri-devel@lists.freedesktop.org Cc: kasan-dev@googlegroups.com Cc: kernel-janitors@vger.kernel.org Cc: linux-block@vger.kernel.org Cc: linux-crypto@vger.kernel.org Cc: linux-doc@vger.kernel.org Cc: linux-fsdevel@vger.kernel.org Cc: linux-media@vger.kernel.org Cc: linux-mm@kvack.org Cc: linux-mmc@vger.kernel.org Cc: linux-mtd@lists.infradead.org Cc: linux-nvme@lists.infradead.org Cc: linux-rdma@vger.kernel.org Cc: linux-usb@vger.kernel.org Cc: linux-wireless@vger.kernel.org Cc: netdev@vger.kernel.org Jason A. Donenfeld (5): treewide: use prandom_u32_max() when possible treewide: use get_random_{u8,u16}() when possible treewide: use get_random_u32() when possible treewide: use get_random_bytes when possible prandom: remove unused functions Documentation/networking/filter.rst | 2 +- arch/powerpc/crypto/crc-vpmsum_test.c | 2 +- arch/x86/mm/pat/cpa-test.c | 4 +- block/blk-crypto-fallback.c | 2 +- crypto/async_tx/raid6test.c | 2 +- crypto/testmgr.c | 94 +++++++++---------- drivers/block/drbd/drbd_receiver.c | 4 +- drivers/dma/dmatest.c | 2 +- drivers/infiniband/core/cma.c | 2 +- drivers/infiniband/hw/cxgb4/cm.c | 4 +- drivers/infiniband/hw/cxgb4/id_table.c | 4 +- drivers/infiniband/hw/hfi1/tid_rdma.c | 2 +- drivers/infiniband/hw/hns/hns_roce_ah.c | 5 +- drivers/infiniband/hw/mlx4/mad.c | 2 +- drivers/infiniband/ulp/ipoib/ipoib_cm.c | 2 +- drivers/infiniband/ulp/rtrs/rtrs-clt.c | 3 +- drivers/md/raid5-cache.c | 2 +- drivers/media/common/v4l2-tpg/v4l2-tpg-core.c | 2 +- .../media/test-drivers/vivid/vivid-radio-rx.c | 4 +- drivers/mmc/core/core.c | 4 +- drivers/mmc/host/dw_mmc.c | 2 +- drivers/mtd/nand/raw/nandsim.c | 8 +- drivers/mtd/tests/mtd_nandecctest.c | 12 +-- drivers/mtd/tests/speedtest.c | 2 +- drivers/mtd/tests/stresstest.c | 19 +--- drivers/mtd/ubi/debug.c | 2 +- drivers/mtd/ubi/debug.h | 6 +- drivers/net/bonding/bond_main.c | 2 +- drivers/net/ethernet/broadcom/bnxt/bnxt.c | 2 +- drivers/net/ethernet/broadcom/cnic.c | 5 +- .../chelsio/inline_crypto/chtls/chtls_cm.c | 4 +- .../chelsio/inline_crypto/chtls/chtls_io.c | 4 +- drivers/net/ethernet/rocker/rocker_main.c | 8 +- drivers/net/hamradio/baycom_epp.c | 2 +- drivers/net/hamradio/hdlcdrv.c | 2 +- drivers/net/hamradio/yam.c | 2 +- drivers/net/phy/at803x.c | 2 +- drivers/net/wireguard/selftest/allowedips.c | 16 ++-- .../broadcom/brcm80211/brcmfmac/p2p.c | 2 +- .../net/wireless/intel/iwlwifi/mvm/mac-ctxt.c | 2 +- .../net/wireless/marvell/mwifiex/cfg80211.c | 4 +- .../wireless/microchip/wilc1000/cfg80211.c | 2 +- .../net/wireless/quantenna/qtnfmac/cfg80211.c | 2 +- drivers/nvme/common/auth.c | 2 +- drivers/scsi/cxgbi/cxgb4i/cxgb4i.c | 4 +- drivers/scsi/fcoe/fcoe_ctlr.c | 4 +- drivers/scsi/lpfc/lpfc_hbadisc.c | 6 +- drivers/scsi/qedi/qedi_main.c | 2 +- drivers/target/iscsi/cxgbit/cxgbit_cm.c | 2 +- drivers/thunderbolt/xdomain.c | 2 +- drivers/video/fbdev/uvesafb.c | 2 +- fs/ceph/inode.c | 2 +- fs/ceph/mdsmap.c | 2 +- fs/exfat/inode.c | 2 +- fs/ext2/ialloc.c | 3 +- fs/ext4/ialloc.c | 7 +- fs/ext4/ioctl.c | 4 +- fs/ext4/mmp.c | 2 +- fs/ext4/super.c | 7 +- fs/f2fs/gc.c | 2 +- fs/f2fs/namei.c | 2 +- fs/f2fs/segment.c | 8 +- fs/fat/inode.c | 2 +- fs/nfsd/nfs4state.c | 4 +- fs/ubifs/debug.c | 10 +- fs/ubifs/journal.c | 2 +- fs/ubifs/lpt_commit.c | 14 +-- fs/ubifs/tnc_commit.c | 2 +- fs/xfs/libxfs/xfs_alloc.c | 2 +- fs/xfs/libxfs/xfs_ialloc.c | 4 +- fs/xfs/xfs_error.c | 2 +- fs/xfs/xfs_icache.c | 2 +- fs/xfs/xfs_log.c | 2 +- include/linux/prandom.h | 12 --- include/net/netfilter/nf_queue.h | 2 +- include/net/red.h | 2 +- include/net/sock.h | 2 +- kernel/kcsan/selftest.c | 4 +- kernel/time/clocksource.c | 2 +- lib/fault-inject.c | 2 +- lib/find_bit_benchmark.c | 4 +- lib/random32.c | 4 +- lib/reed_solomon/test_rslib.c | 12 +-- lib/sbitmap.c | 4 +- lib/test_fprobe.c | 2 +- lib/test_kprobes.c | 2 +- lib/test_list_sort.c | 2 +- lib/test_objagg.c | 2 +- lib/test_rhashtable.c | 6 +- lib/test_vmalloc.c | 19 +--- lib/uuid.c | 2 +- mm/shmem.c | 2 +- net/802/garp.c | 2 +- net/802/mrp.c | 2 +- net/ceph/mon_client.c | 2 +- net/ceph/osd_client.c | 2 +- net/core/neighbour.c | 2 +- net/core/pktgen.c | 47 +++++----- net/core/stream.c | 2 +- net/dccp/ipv4.c | 4 +- net/ipv4/datagram.c | 2 +- net/ipv4/igmp.c | 6 +- net/ipv4/inet_connection_sock.c | 2 +- net/ipv4/inet_hashtables.c | 2 +- net/ipv4/ip_output.c | 2 +- net/ipv4/route.c | 2 +- net/ipv4/tcp_cdg.c | 2 +- net/ipv4/tcp_ipv4.c | 4 +- net/ipv4/udp.c | 2 +- net/ipv6/addrconf.c | 8 +- net/ipv6/ip6_flowlabel.c | 2 +- net/ipv6/mcast.c | 10 +- net/ipv6/output_core.c | 2 +- net/mac80211/rc80211_minstrel_ht.c | 2 +- net/mac80211/scan.c | 2 +- net/netfilter/ipvs/ip_vs_conn.c | 2 +- net/netfilter/ipvs/ip_vs_twos.c | 4 +- net/netfilter/nf_nat_core.c | 4 +- net/netfilter/xt_statistic.c | 2 +- net/openvswitch/actions.c | 2 +- net/packet/af_packet.c | 2 +- net/rds/bind.c | 2 +- net/sched/act_gact.c | 2 +- net/sched/act_sample.c | 2 +- net/sched/sch_cake.c | 8 +- net/sched/sch_netem.c | 22 ++--- net/sched/sch_pie.c | 2 +- net/sched/sch_sfb.c | 2 +- net/sctp/socket.c | 4 +- net/sunrpc/auth_gss/gss_krb5_wrap.c | 4 +- net/sunrpc/cache.c | 2 +- net/sunrpc/xprt.c | 2 +- net/sunrpc/xprtsock.c | 2 +- net/tipc/socket.c | 2 +- net/unix/af_unix.c | 2 +- net/xfrm/xfrm_state.c | 2 +- 136 files changed, 305 insertions(+), 342 deletions(-)