On Thu, 6 Oct 2022 at 18:54, Jason A. Donenfeld <Jason@xxxxxxxxx> wrote: > > Changes v2->v3: > - Handle get_random_int() conversions too, which were overlooked before, > in the same way as the rest. > > 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, 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() and > get_random_int() 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! At "379 insertions(+), 422 deletions(-)", this > should be a somewhat small patchset to review, despite it having the > scary "treewide" moniker on it. > > Thanks, > Jason > > Cc: Andreas Noever <andreas.noever@xxxxxxxxx> > Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > Cc: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> > Cc: Borislav Petkov <bp@xxxxxxxxx> > Cc: Catalin Marinas <catalin.marinas@xxxxxxx> > Cc: Christoph Böhmwalder <christoph.boehmwalder@xxxxxxxxxx> > Cc: Christoph Hellwig <hch@xxxxxx> > Cc: Christophe Leroy <christophe.leroy@xxxxxxxxxx> > Cc: Daniel Borkmann <daniel@xxxxxxxxxxxxx> > Cc: Dave Airlie <airlied@xxxxxxxxxx> > Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx> > Cc: David S. Miller <davem@xxxxxxxxxxxxx> > Cc: Eric Dumazet <edumazet@xxxxxxxxxx> > Cc: Florian Westphal <fw@xxxxxxxxx> > Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>, > Cc: H. Peter Anvin <hpa@xxxxxxxxx> > Cc: Heiko Carstens <hca@xxxxxxxxxxxxx> > Cc: Helge Deller <deller@xxxxxx> > Cc: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> > Cc: Huacai Chen <chenhuacai@xxxxxxxxxx> > Cc: Hugh Dickins <hughd@xxxxxxxxxx> > Cc: Jakub Kicinski <kuba@xxxxxxxxxx> > Cc: James E.J. Bottomley <jejb@xxxxxxxxxxxxx> > Cc: Jan Kara <jack@xxxxxxxx> > Cc: Jason Gunthorpe <jgg@xxxxxxxx> > Cc: Jens Axboe <axboe@xxxxxxxxx> > Cc: Johannes Berg <johannes@xxxxxxxxxxxxxxxx> > Cc: Jonathan Corbet <corbet@xxxxxxx> > Cc: Jozsef Kadlecsik <kadlec@xxxxxxxxxxxxx> > Cc: KP Singh <kpsingh@xxxxxxxxxx> > Cc: Kees Cook <keescook@xxxxxxxxxxxx> > Cc: Marco Elver <elver@xxxxxxxxxx> > Cc: Mauro Carvalho Chehab <mchehab@xxxxxxxxxx> > Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> > Cc: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> > Cc: Paolo Abeni <pabeni@xxxxxxxxxx> > Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> > Cc: Richard Weinberger <richard@xxxxxx> > Cc: Russell King <linux@xxxxxxxxxxxxxxx> > Cc: Theodore Ts'o <tytso@xxxxxxx> > Cc: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx> > Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> > Cc: Thomas Graf <tgraf@xxxxxxx> > Cc: Ulf Hansson <ulf.hansson@xxxxxxxxxx> > Cc: Vignesh Raghavendra <vigneshr@xxxxxx> > Cc: WANG Xuerui <kernel@xxxxxxxxxx> > Cc: Will Deacon <will@xxxxxxxxxx> > Cc: Yury Norov <yury.norov@xxxxxxxxx> > Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx > Cc: kasan-dev@xxxxxxxxxxxxxxxx > Cc: kernel-janitors@xxxxxxxxxxxxxxx > Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx > Cc: linux-block@xxxxxxxxxxxxxxx > Cc: linux-crypto@xxxxxxxxxxxxxxx > Cc: linux-doc@xxxxxxxxxxxxxxx > Cc: linux-fsdevel@xxxxxxxxxxxxxxx > Cc: linux-media@xxxxxxxxxxxxxxx > Cc: linux-mips@xxxxxxxxxxxxxxx > Cc: linux-mm@xxxxxxxxx > Cc: linux-mmc@xxxxxxxxxxxxxxx > Cc: linux-mtd@xxxxxxxxxxxxxxxxxxx > Cc: linux-nvme@xxxxxxxxxxxxxxxxxxx > Cc: linux-parisc@xxxxxxxxxxxxxxx > Cc: linux-rdma@xxxxxxxxxxxxxxx > Cc: linux-s390@xxxxxxxxxxxxxxx > Cc: linux-um@xxxxxxxxxxxxxxxxxxx > Cc: linux-usb@xxxxxxxxxxxxxxx > Cc: linux-wireless@xxxxxxxxxxxxxxx > Cc: linuxppc-dev@xxxxxxxxxxxxxxxx > Cc: loongarch@xxxxxxxxxxxxxxx > Cc: netdev@xxxxxxxxxxxxxxx > Cc: sparclinux@xxxxxxxxxxxxxxx > Cc: x86@xxxxxxxxxx > > 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/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/selftests/test-drm_buddy.c | 2 +- > drivers/gpu/drm/selftests/test-drm_mm.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(-) > Acked-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx> # For MMC Kind regards Uffe