From patchwork Thu Oct 6 13:25:07 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Jason A. Donenfeld" X-Patchwork-Id: 13000341 X-Patchwork-Delegate: kuba@kernel.org 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 BD386C4167E for ; Thu, 6 Oct 2022 13:27:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231482AbiJFN10 (ORCPT ); Thu, 6 Oct 2022 09:27:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34324 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231452AbiJFN0m (ORCPT ); Thu, 6 Oct 2022 09:26:42 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B2BA1A98DF; Thu, 6 Oct 2022 06:26:04 -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 ams.source.kernel.org (Postfix) with ESMTPS id BA5EDB820A9; Thu, 6 Oct 2022 13:26:02 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 233C3C43147; Thu, 6 Oct 2022 13:25:57 +0000 (UTC) Authentication-Results: smtp.kernel.org; dkim=pass (1024-bit key) header.d=zx2c4.com header.i=@zx2c4.com header.b="pwC9cMHz" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=zx2c4.com; s=20210105; t=1665062756; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=RNYWpm9q3FealxpvsZD8zZkjod1MIfG1X8OEo9MwlyM=; b=pwC9cMHzLyk+dj7008fR/ind61uVxSjoIGURU1q3vh2bmEs3LMcg+WI4sJQilc353gyFEJ 6+5GOGfrp5DubkvWh7SmDIqyITlo61jX4kEQOE4tSl6lc5hWhuT2TKL4nF2imEMovH/Ry9 z0MTMVAl9hEg7BFeJ1ELed46Mw9aQtI= Received: by mail.zx2c4.com (ZX2C4 Mail Server) with ESMTPSA id 5395c60d (TLSv1.3:TLS_AES_256_GCM_SHA384:256:NO); Thu, 6 Oct 2022 13:25:55 +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 2/5] treewide: use get_random_{u8,u16}() when possible Date: Thu, 6 Oct 2022 07:25:07 -0600 Message-Id: <20221006132510.23374-3-Jason@zx2c4.com> In-Reply-To: <20221006132510.23374-1-Jason@zx2c4.com> References: <20221006132510.23374-1-Jason@zx2c4.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org Rather than truncate a 32-bit value to a 16-bit value or an 8-bit value, simply use the get_random_{u8,u16}() functions, which are faster than wasting the additional bytes from a 32-bit value. Reviewed-by: Kees Cook Signed-off-by: Jason A. Donenfeld --- crypto/testmgr.c | 8 ++++---- drivers/media/common/v4l2-tpg/v4l2-tpg-core.c | 2 +- drivers/media/test-drivers/vivid/vivid-radio-rx.c | 4 ++-- .../net/ethernet/chelsio/inline_crypto/chtls/chtls_cm.c | 2 +- drivers/net/hamradio/baycom_epp.c | 2 +- drivers/net/hamradio/hdlcdrv.c | 2 +- drivers/net/hamradio/yam.c | 2 +- drivers/net/wireguard/selftest/allowedips.c | 4 ++-- drivers/scsi/lpfc/lpfc_hbadisc.c | 6 +++--- lib/test_vmalloc.c | 2 +- net/dccp/ipv4.c | 4 ++-- net/ipv4/datagram.c | 2 +- net/ipv4/ip_output.c | 2 +- net/ipv4/tcp_ipv4.c | 4 ++-- net/mac80211/scan.c | 2 +- net/netfilter/nf_nat_core.c | 4 ++-- net/sched/sch_cake.c | 6 +++--- net/sched/sch_sfb.c | 2 +- net/sctp/socket.c | 2 +- 19 files changed, 31 insertions(+), 31 deletions(-) diff --git a/crypto/testmgr.c b/crypto/testmgr.c index be45217acde4..981c637fa2ed 100644 --- a/crypto/testmgr.c +++ b/crypto/testmgr.c @@ -927,7 +927,7 @@ static void generate_random_bytes(u8 *buf, size_t count) b = 0xff; break; default: - b = (u8)prandom_u32(); + b = get_random_u8(); break; } memset(buf, b, count); @@ -935,8 +935,8 @@ static void generate_random_bytes(u8 *buf, size_t count) break; case 2: /* Ascending or descending bytes, plus optional mutations */ - increment = (u8)prandom_u32(); - b = (u8)prandom_u32(); + increment = get_random_u8(); + b = get_random_u8(); for (i = 0; i < count; i++, b += increment) buf[i] = b; mutate_buffer(buf, count); @@ -944,7 +944,7 @@ static void generate_random_bytes(u8 *buf, size_t count) default: /* Fully random bytes */ for (i = 0; i < count; i++) - buf[i] = (u8)prandom_u32(); + buf[i] = get_random_u8(); } } diff --git a/drivers/media/common/v4l2-tpg/v4l2-tpg-core.c b/drivers/media/common/v4l2-tpg/v4l2-tpg-core.c index 9b7bcdce6e44..303d02b1d71c 100644 --- a/drivers/media/common/v4l2-tpg/v4l2-tpg-core.c +++ b/drivers/media/common/v4l2-tpg/v4l2-tpg-core.c @@ -870,7 +870,7 @@ static void precalculate_color(struct tpg_data *tpg, int k) g = tpg_colors[col].g; b = tpg_colors[col].b; } else if (tpg->pattern == TPG_PAT_NOISE) { - r = g = b = prandom_u32_max(256); + r = g = b = get_random_u8(); } else if (k == TPG_COLOR_RANDOM) { r = g = b = tpg->qual_offset + prandom_u32_max(196); } else if (k >= TPG_COLOR_RAMP) { diff --git a/drivers/media/test-drivers/vivid/vivid-radio-rx.c b/drivers/media/test-drivers/vivid/vivid-radio-rx.c index 232cab508f48..8bd09589fb15 100644 --- a/drivers/media/test-drivers/vivid/vivid-radio-rx.c +++ b/drivers/media/test-drivers/vivid/vivid-radio-rx.c @@ -104,8 +104,8 @@ ssize_t vivid_radio_rx_read(struct file *file, char __user *buf, break; case 2: rds.block |= V4L2_RDS_BLOCK_ERROR; - rds.lsb = prandom_u32_max(256); - rds.msb = prandom_u32_max(256); + rds.lsb = get_random_u8(); + rds.msb = get_random_u8(); break; case 3: /* Skip block altogether */ if (i) diff --git a/drivers/net/ethernet/chelsio/inline_crypto/chtls/chtls_cm.c b/drivers/net/ethernet/chelsio/inline_crypto/chtls/chtls_cm.c index ddfe9208529a..ac452a0111a9 100644 --- a/drivers/net/ethernet/chelsio/inline_crypto/chtls/chtls_cm.c +++ b/drivers/net/ethernet/chelsio/inline_crypto/chtls/chtls_cm.c @@ -1467,7 +1467,7 @@ static void make_established(struct sock *sk, u32 snd_isn, unsigned int opt) tp->write_seq = snd_isn; tp->snd_nxt = snd_isn; tp->snd_una = snd_isn; - inet_sk(sk)->inet_id = prandom_u32(); + inet_sk(sk)->inet_id = get_random_u16(); assign_rxopt(sk, opt); if (tp->rcv_wnd > (RCV_BUFSIZ_M << 10)) diff --git a/drivers/net/hamradio/baycom_epp.c b/drivers/net/hamradio/baycom_epp.c index 7df78a721b04..791b4a53d69f 100644 --- a/drivers/net/hamradio/baycom_epp.c +++ b/drivers/net/hamradio/baycom_epp.c @@ -438,7 +438,7 @@ static int transmit(struct baycom_state *bc, int cnt, unsigned char stat) if ((--bc->hdlctx.slotcnt) > 0) return 0; bc->hdlctx.slotcnt = bc->ch_params.slottime; - if (prandom_u32_max(256) > bc->ch_params.ppersist) + if (get_random_u8() > bc->ch_params.ppersist) return 0; } } diff --git a/drivers/net/hamradio/hdlcdrv.c b/drivers/net/hamradio/hdlcdrv.c index 360d041a62c4..6c6f11d3d0aa 100644 --- a/drivers/net/hamradio/hdlcdrv.c +++ b/drivers/net/hamradio/hdlcdrv.c @@ -377,7 +377,7 @@ void hdlcdrv_arbitrate(struct net_device *dev, struct hdlcdrv_state *s) if ((--s->hdlctx.slotcnt) > 0) return; s->hdlctx.slotcnt = s->ch_params.slottime; - if (prandom_u32_max(256) > s->ch_params.ppersist) + if (get_random_u8() > s->ch_params.ppersist) return; start_tx(dev, s); } diff --git a/drivers/net/hamradio/yam.c b/drivers/net/hamradio/yam.c index 97a6cc5c7ae8..2ed2f836f09a 100644 --- a/drivers/net/hamradio/yam.c +++ b/drivers/net/hamradio/yam.c @@ -626,7 +626,7 @@ static void yam_arbitrate(struct net_device *dev) yp->slotcnt = yp->slot / 10; /* is random > persist ? */ - if (prandom_u32_max(256) > yp->pers) + if (get_random_u8() > yp->pers) return; yam_start_tx(dev, yp); diff --git a/drivers/net/wireguard/selftest/allowedips.c b/drivers/net/wireguard/selftest/allowedips.c index 41db10f9be49..dd897c0740a2 100644 --- a/drivers/net/wireguard/selftest/allowedips.c +++ b/drivers/net/wireguard/selftest/allowedips.c @@ -310,7 +310,7 @@ static __init bool randomized_test(void) for (k = 0; k < 4; ++k) mutated[k] = (mutated[k] & mutate_mask[k]) | (~mutate_mask[k] & - prandom_u32_max(256)); + get_random_u8()); cidr = prandom_u32_max(32) + 1; peer = peers[prandom_u32_max(NUM_PEERS)]; if (wg_allowedips_insert_v4(&t, @@ -354,7 +354,7 @@ static __init bool randomized_test(void) for (k = 0; k < 4; ++k) mutated[k] = (mutated[k] & mutate_mask[k]) | (~mutate_mask[k] & - prandom_u32_max(256)); + get_random_u8()); cidr = prandom_u32_max(128) + 1; peer = peers[prandom_u32_max(NUM_PEERS)]; if (wg_allowedips_insert_v6(&t, diff --git a/drivers/scsi/lpfc/lpfc_hbadisc.c b/drivers/scsi/lpfc/lpfc_hbadisc.c index 2645def612e6..26d1779cb570 100644 --- a/drivers/scsi/lpfc/lpfc_hbadisc.c +++ b/drivers/scsi/lpfc/lpfc_hbadisc.c @@ -2150,8 +2150,8 @@ lpfc_check_pending_fcoe_event(struct lpfc_hba *phba, uint8_t unreg_fcf) * This function makes an running random selection decision on FCF record to * use through a sequence of @fcf_cnt eligible FCF records with equal * probability. To perform integer manunipulation of random numbers with - * size unit32_t, the lower 16 bits of the 32-bit random number returned - * from prandom_u32() are taken as the random random number generated. + * size unit32_t, a 16-bit random number returned from get_random_u16() is + * taken as the random random number generated. * * Returns true when outcome is for the newly read FCF record should be * chosen; otherwise, return false when outcome is for keeping the previously @@ -2163,7 +2163,7 @@ lpfc_sli4_new_fcf_random_select(struct lpfc_hba *phba, uint32_t fcf_cnt) uint32_t rand_num; /* Get 16-bit uniform random number */ - rand_num = 0xFFFF & prandom_u32(); + rand_num = get_random_u16(); /* Decision with probability 1/fcf_cnt */ if ((fcf_cnt * rand_num) < 0xFFFF) diff --git a/lib/test_vmalloc.c b/lib/test_vmalloc.c index 56ffaa8dd3f6..0131ed2cd1bd 100644 --- a/lib/test_vmalloc.c +++ b/lib/test_vmalloc.c @@ -80,7 +80,7 @@ static int random_size_align_alloc_test(void) int i; for (i = 0; i < test_loop_count; i++) { - rnd = prandom_u32(); + rnd = get_random_u8(); /* * Maximum 1024 pages, if PAGE_SIZE is 4096. diff --git a/net/dccp/ipv4.c b/net/dccp/ipv4.c index da6e3b20cd75..301799e7fa56 100644 --- a/net/dccp/ipv4.c +++ b/net/dccp/ipv4.c @@ -123,7 +123,7 @@ int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) inet->inet_daddr, inet->inet_sport, inet->inet_dport); - inet->inet_id = prandom_u32(); + inet->inet_id = get_random_u16(); err = dccp_connect(sk); rt = NULL; @@ -422,7 +422,7 @@ struct sock *dccp_v4_request_recv_sock(const struct sock *sk, RCU_INIT_POINTER(newinet->inet_opt, rcu_dereference(ireq->ireq_opt)); newinet->mc_index = inet_iif(skb); newinet->mc_ttl = ip_hdr(skb)->ttl; - newinet->inet_id = prandom_u32(); + newinet->inet_id = get_random_u16(); if (dst == NULL && (dst = inet_csk_route_child_sock(sk, newsk, req)) == NULL) goto put_and_exit; diff --git a/net/ipv4/datagram.c b/net/ipv4/datagram.c index ffd57523331f..fefc5d855a66 100644 --- a/net/ipv4/datagram.c +++ b/net/ipv4/datagram.c @@ -71,7 +71,7 @@ int __ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len reuseport_has_conns(sk, true); sk->sk_state = TCP_ESTABLISHED; sk_set_txhash(sk); - inet->inet_id = prandom_u32(); + inet->inet_id = get_random_u16(); sk_dst_set(sk, &rt->dst); err = 0; diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c index 04e2034f2f8e..a4fbdbff14b3 100644 --- a/net/ipv4/ip_output.c +++ b/net/ipv4/ip_output.c @@ -172,7 +172,7 @@ int ip_build_and_send_pkt(struct sk_buff *skb, const struct sock *sk, * Avoid using the hashed IP ident generator. */ if (sk->sk_protocol == IPPROTO_TCP) - iph->id = (__force __be16)prandom_u32(); + iph->id = (__force __be16)get_random_u16(); else __ip_select_ident(net, iph, 1); } diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 5b019ba2b9d2..747752980983 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -303,7 +303,7 @@ int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) inet->inet_daddr); } - inet->inet_id = prandom_u32(); + inet->inet_id = get_random_u16(); if (tcp_fastopen_defer_connect(sk, &err)) return err; @@ -1523,7 +1523,7 @@ struct sock *tcp_v4_syn_recv_sock(const struct sock *sk, struct sk_buff *skb, inet_csk(newsk)->icsk_ext_hdr_len = 0; if (inet_opt) inet_csk(newsk)->icsk_ext_hdr_len = inet_opt->opt.optlen; - newinet->inet_id = prandom_u32(); + newinet->inet_id = get_random_u16(); /* Set ToS of the new socket based upon the value of incoming SYN. * ECT bits are set later in tcp_init_transfer(). diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c index c4f2aeb31da3..6cab549cc421 100644 --- a/net/mac80211/scan.c +++ b/net/mac80211/scan.c @@ -641,7 +641,7 @@ static void ieee80211_send_scan_probe_req(struct ieee80211_sub_if_data *sdata, if (flags & IEEE80211_PROBE_FLAG_RANDOM_SN) { struct ieee80211_hdr *hdr = (void *)skb->data; struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); - u16 sn = get_random_u32(); + u16 sn = get_random_u16(); info->control.flags |= IEEE80211_TX_CTRL_NO_SEQNO; hdr->seq_ctrl = diff --git a/net/netfilter/nf_nat_core.c b/net/netfilter/nf_nat_core.c index 7981be526f26..57c7686ac485 100644 --- a/net/netfilter/nf_nat_core.c +++ b/net/netfilter/nf_nat_core.c @@ -468,7 +468,7 @@ static void nf_nat_l4proto_unique_tuple(struct nf_conntrack_tuple *tuple, if (range->flags & NF_NAT_RANGE_PROTO_OFFSET) off = (ntohs(*keyptr) - ntohs(range->base_proto.all)); else - off = prandom_u32(); + off = get_random_u16(); attempts = range_size; if (attempts > max_attempts) @@ -490,7 +490,7 @@ static void nf_nat_l4proto_unique_tuple(struct nf_conntrack_tuple *tuple, if (attempts >= range_size || attempts < 16) return; attempts /= 2; - off = prandom_u32(); + off = get_random_u16(); goto another_round; } diff --git a/net/sched/sch_cake.c b/net/sched/sch_cake.c index a43a58a73d09..637ef1757931 100644 --- a/net/sched/sch_cake.c +++ b/net/sched/sch_cake.c @@ -2092,11 +2092,11 @@ static struct sk_buff *cake_dequeue(struct Qdisc *sch) WARN_ON(host_load > CAKE_QUEUES); - /* The shifted prandom_u32() is a way to apply dithering to - * avoid accumulating roundoff errors + /* The get_random_u16() is a way to apply dithering to avoid + * accumulating roundoff errors */ flow->deficit += (b->flow_quantum * quantum_div[host_load] + - (prandom_u32() >> 16)) >> 16; + get_random_u16()) >> 16; list_move_tail(&flow->flowchain, &b->old_flows); goto retry; diff --git a/net/sched/sch_sfb.c b/net/sched/sch_sfb.c index 2829455211f8..7eb70acb4d58 100644 --- a/net/sched/sch_sfb.c +++ b/net/sched/sch_sfb.c @@ -379,7 +379,7 @@ static int sfb_enqueue(struct sk_buff *skb, struct Qdisc *sch, goto enqueue; } - r = prandom_u32() & SFB_MAX_PROB; + r = get_random_u16() & SFB_MAX_PROB; if (unlikely(r < p_min)) { if (unlikely(p_min > SFB_MAX_PROB / 2)) { diff --git a/net/sctp/socket.c b/net/sctp/socket.c index 1e354ba44960..83628c347744 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -9448,7 +9448,7 @@ void sctp_copy_sock(struct sock *newsk, struct sock *sk, newinet->inet_rcv_saddr = inet->inet_rcv_saddr; newinet->inet_dport = htons(asoc->peer.port); newinet->pmtudisc = inet->pmtudisc; - newinet->inet_id = prandom_u32(); + newinet->inet_id = get_random_u16(); newinet->uc_ttl = inet->uc_ttl; newinet->mc_loop = 1;