Message ID | 20221010230613.1076905-1-Jason@zx2c4.com (mailing list archive) |
---|---|
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>
On 2022/10/11 7:06, Jason A. Donenfeld Wrote: > 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(-) > Hi, Jason: There is a lot of code using "prandom_u32 % 4" in crypto's kernel self-test file testmgr.c, can you modify it together? Thanks, Longfang.