| Message ID | 20221010230613.1076905-1-Jason@zx2c4.com |
|---|---|
| Headers | show |
| Series | treewide cleanup of random integer usage | expand |
On Mon, 10 Oct 2022 17:06:06 -0600 Jason A. Donenfeld wrote: > - 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(). Same for > get_random_int(). > - 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. Acked-by: Jakub Kicinski <kuba@kernel.org>
Am Donnerstag, 13. Oktober 2022, 12:16:35 CEST schrieb Florian Westphal: > Rolf Eike Beer <eike-kernel@sf-tec.de> wrote: > > Florian, can you comment and maybe fix it? > > Can't comment, do not remember -- this was 5 years ago. > > > Or you wanted to move the variable before the loop and keep the random > > state between the loops and only reseed when all '1' bits have been > > consumed. > Probably. No clue, best to NOT change it to not block Jasons series and > then just simplify this and remove all the useless shifts. Sure. Jason, just in case you are going to do a v7 this could move to u8 then.
On Thu, Oct 13, 2022 at 01:40:40PM +0200, Rolf Eike Beer wrote: > Am Donnerstag, 13. Oktober 2022, 12:16:35 CEST schrieb Florian Westphal: > > Rolf Eike Beer <eike-kernel@sf-tec.de> wrote: > > > Florian, can you comment and maybe fix it? > > > > Can't comment, do not remember -- this was 5 years ago. > > > > > Or you wanted to move the variable before the loop and keep the random > > > state between the loops and only reseed when all '1' bits have been > > > consumed. > > Probably. No clue, best to NOT change it to not block Jasons series and > > then just simplify this and remove all the useless shifts. > > Sure. Jason, just in case you are going to do a v7 this could move to u8 then. Indeed I think this is one to send individually to netdev@ once the tree opens there for 6.2. Jason
Changes v5->v6: - Added a few missing conversions that weren't in my older tree, so now this should be ready to go, as well as a couple nits people had from v5. Barring something large and unforeseen, this is the "final version", as this is ready to ship. Thanks to everyone who reviewed this. 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(). Same for get_random_int(). - 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: 1) Replace `prandom_u32() % max` and variants thereof with prandom_u32_max(max). * Part 1 is done with Coccinelle. Part 2 is done by hand. 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. * Part 1 is done with Coccinelle. Part 2 is done by hand. 3) Replace remaining deprecated uses of prandom_u32() and get_random_int() with get_random_u32(). * A boring search and replace operation. 4) Replace remaining deprecated uses of prandom_bytes() with get_random_bytes(). * A boring search and replace operation. 5) Remove the deprecated and now-unused prandom_u32() and prandom_bytes() inline wrapper functions. * Just deleting code and updating comments. I'll be sending this toward the end of the 6.1 merge window via the random.git tree. Please take a look! The number of lines touched is quite small, so this should be reviewable, and as much as is possible has been pushed into Coccinelle scripts. Thanks, Jason Cc: Andreas Noever <andreas.noever@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Dave Airlie <airlied@redhat.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David S. Miller <davem@davemloft.net> Cc: Eric Dumazet <edumazet@google.com> Cc: Florian Westphal <fw@strlen.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>, Cc: H. Peter Anvin <hpa@zytor.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Hugh Dickins <hughd@google.com> Cc: Jakub Kicinski <kuba@kernel.org> Cc: James E.J. Bottomley <jejb@linux.ibm.com> Cc: Jan Kara <jack@suse.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jens Axboe <axboe@kernel.dk> Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Jozsef Kadlecsik <kadlec@netfilter.org> Cc: KP Singh <kpsingh@kernel.org> Cc: Kees Cook <keescook@chromium.org> Cc: Marco Elver <elver@google.com> Cc: Mauro Carvalho Chehab <mchehab@kernel.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Pablo Neira Ayuso <pablo@netfilter.org> Cc: Paolo Abeni <pabeni@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Richard Weinberger <richard@nod.at> Cc: Russell King <linux@armlinux.org.uk> Cc: Theodore Ts'o <tytso@mit.edu> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Thomas Graf <tgraf@suug.ch> Cc: Ulf Hansson <ulf.hansson@linaro.org> Cc: Vignesh Raghavendra <vigneshr@ti.com> Cc: WANG Xuerui <kernel@xen0n.name> Cc: Will Deacon <will@kernel.org> Cc: Yury Norov <yury.norov@gmail.com> Cc: dri-devel@lists.freedesktop.org Cc: kasan-dev@googlegroups.com Cc: kernel-janitors@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.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-mips@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-parisc@vger.kernel.org Cc: linux-rdma@vger.kernel.org Cc: linux-s390@vger.kernel.org Cc: linux-um@lists.infradead.org Cc: linux-usb@vger.kernel.org Cc: linux-wireless@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: loongarch@lists.linux.dev Cc: netdev@vger.kernel.org Cc: sparclinux@vger.kernel.org Cc: x86@kernel.org Jason A. Donenfeld (7): treewide: use prandom_u32_max() when possible, part 1 treewide: use prandom_u32_max() when possible, part 2 treewide: use get_random_{u8,u16}() when possible, part 1 treewide: use get_random_{u8,u16}() when possible, part 2 treewide: use get_random_u32() when possible treewide: use get_random_bytes() when possible prandom: remove unused functions Documentation/networking/filter.rst | 2 +- arch/arm/kernel/process.c | 2 +- arch/arm/kernel/signal.c | 2 +- arch/arm64/kernel/process.c | 2 +- arch/arm64/kernel/syscall.c | 2 +- arch/loongarch/kernel/process.c | 2 +- arch/loongarch/kernel/vdso.c | 2 +- arch/mips/kernel/process.c | 2 +- arch/mips/kernel/vdso.c | 2 +- arch/parisc/kernel/process.c | 2 +- arch/parisc/kernel/sys_parisc.c | 4 +- arch/parisc/kernel/vdso.c | 2 +- arch/powerpc/crypto/crc-vpmsum_test.c | 2 +- arch/powerpc/kernel/process.c | 2 +- arch/s390/kernel/process.c | 4 +- arch/s390/kernel/vdso.c | 2 +- arch/s390/mm/mmap.c | 2 +- arch/sparc/vdso/vma.c | 2 +- arch/um/kernel/process.c | 2 +- arch/x86/entry/vdso/vma.c | 2 +- arch/x86/kernel/cpu/amd.c | 2 +- arch/x86/kernel/module.c | 2 +- arch/x86/kernel/process.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/char/random.c | 11 +-- drivers/dma/dmatest.c | 2 +- .../gpu/drm/i915/gem/i915_gem_execbuffer.c | 2 +- drivers/gpu/drm/i915/i915_gem_gtt.c | 6 +- .../gpu/drm/i915/selftests/i915_selftest.c | 2 +- drivers/gpu/drm/tests/drm_buddy_test.c | 2 +- drivers/gpu/drm/tests/drm_mm_test.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/bcache/request.c | 2 +- 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 +- .../test-drivers/vivid/vivid-touch-cap.c | 6 +- drivers/misc/habanalabs/gaudi2/gaudi2.c | 2 +- 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 +- .../broadcom/brcm80211/brcmfmac/pno.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/net/wireless/st/cw1200/wsm.c | 2 +- drivers/net/wireless/ti/wlcore/main.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/ntfs3/fslog.c | 6 +- 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/nodemask.h | 2 +- include/linux/prandom.h | 12 --- include/linux/random.h | 5 - include/net/netfilter/nf_queue.h | 2 +- include/net/red.h | 2 +- include/net/sock.h | 2 +- kernel/bpf/bloom_filter.c | 2 +- kernel/bpf/core.c | 6 +- kernel/bpf/hashtab.c | 2 +- kernel/bpf/verifier.c | 2 +- kernel/kcsan/selftest.c | 4 +- kernel/locking/test-ww_mutex.c | 4 +- kernel/time/clocksource.c | 2 +- lib/cmdline_kunit.c | 4 +- lib/fault-inject.c | 2 +- lib/find_bit_benchmark.c | 4 +- lib/kobject.c | 2 +- lib/random32.c | 4 +- lib/reed_solomon/test_rslib.c | 12 +-- lib/sbitmap.c | 4 +- lib/test-string_helpers.c | 2 +- lib/test_fprobe.c | 2 +- lib/test_hexdump.c | 10 +- lib/test_kasan.c | 6 +- lib/test_kprobes.c | 2 +- lib/test_list_sort.c | 2 +- lib/test_min_heap.c | 6 +- lib/test_objagg.c | 2 +- lib/test_rhashtable.c | 6 +- lib/test_vmalloc.c | 19 +--- lib/uuid.c | 2 +- mm/migrate.c | 2 +- mm/shmem.c | 2 +- mm/slab.c | 2 +- mm/slub.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 | 4 +- 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 +- 186 files changed, 379 insertions(+), 422 deletions(-)