kernel/linux.git/lib/random32.c, branch v6.19.11

Merge tag 'random-6.13-rc1-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random

2024-11-19T18:43:44+00:00

Pull random number generator updates from Jason Donenfeld: "This contains a single series from Uros to replace uses of with prandom.h or other more specific headers as needed, in order to avoid a circular header issue. Uros' goal is to be able to use percpu.h from prandom.h, which will then allow him to define __percpu in percpu.h rather than in compiler_types.h" * tag 'random-6.13-rc1-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random: prandom: Include in random: Do not include in netem: Include in sch_netem.c lib/test_scanf: Include instead of lib/test_parman: Include instead of bpf/tests: Include instead of lib/rbtree-test: Include instead of random32: Include instead of kunit: string-stream-test: Include lib/interval_tree_test.c: Include instead of bpf: Include instead of scsi: libfcoe: Include instead of fscrypt: Include in fs/crypto/keyring.c mtd: tests: Include instead of media: vivid: Include in vivid-vid-cap.c drm/lib: Include instead of drm/i915/selftests: Include instead of crypto: testmgr: Include instead of x86/kaslr: Include instead of

random32: Include instead of

2024-10-03T16:20:17+00:00

Substitute the inclusion of header with to allow the removal of legacy inclusion of from . Signed-off-by: Uros Bizjak Cc: Andrew Morton Cc: David S. Miller Cc: Eric Dumazet Cc: Jakub Kicinski Cc: Paolo Abeni Signed-off-by: Jason A. Donenfeld

move asm/unaligned.h to linux/unaligned.h

2024-10-02T21:23:23+00:00

asm/unaligned.h is always an include of asm-generic/unaligned.h; might as well move that thing to linux/unaligned.h and include that - there's nothing arch-specific in that header. auto-generated by the following: for i in `git grep -l -w asm/unaligned.h`; do sed -i -e "s/asm\/unaligned.h/linux\/unaligned.h/" $i done for i in `git grep -l -w asm-generic/unaligned.h`; do sed -i -e "s/asm-generic\/unaligned.h/linux\/unaligned.h/" $i done git mv include/asm-generic/unaligned.h include/linux/unaligned.h git mv tools/include/asm-generic/unaligned.h tools/include/linux/unaligned.h sed -i -e "/unaligned.h/d" include/asm-generic/Kbuild sed -i -e "s/__ASM_GENERIC/__LINUX/" include/linux/unaligned.h tools/include/linux/unaligned.h

treewide: use get_random_bytes() when possible

2022-10-11T23:42:58+00:00

The prandom_bytes() function has been a deprecated inline wrapper around get_random_bytes() for several releases now, and compiles down to the exact same code. Replace the deprecated wrapper with a direct call to the real function. This was done as a basic find and replace. Reviewed-by: Greg Kroah-Hartman Reviewed-by: Kees Cook Reviewed-by: Yury Norov Reviewed-by: Christophe Leroy # powerpc Acked-by: Jakub Kicinski Signed-off-by: Jason A. Donenfeld

treewide: use get_random_u32() when possible

2022-10-11T23:42:58+00:00

The prandom_u32() function has been a deprecated inline wrapper around get_random_u32() for several releases now, and compiles down to the exact same code. Replace the deprecated wrapper with a direct call to the real function. The same also applies to get_random_int(), which is just a wrapper around get_random_u32(). This was done as a basic find and replace. Reviewed-by: Greg Kroah-Hartman Reviewed-by: Kees Cook Reviewed-by: Yury Norov Reviewed-by: Jan Kara # for ext4 Acked-by: Toke Høiland-Jørgensen # for sch_cake Acked-by: Chuck Lever # for nfsd Acked-by: Jakub Kicinski Acked-by: Mika Westerberg # for thunderbolt Acked-by: Darrick J. Wong # for xfs Acked-by: Helge Deller # for parisc Acked-by: Heiko Carstens # for s390 Signed-off-by: Jason A. Donenfeld

random32: use real rng for non-deterministic randomness

2022-05-18T13:53:52+00:00

random32.c has two random number generators in it: one that is meant to be used deterministically, with some predefined seed, and one that does the same exact thing as random.c, except does it poorly. The first one has some use cases. The second one no longer does and can be replaced with calls to random.c's proper random number generator. The relatively recent siphash-based bad random32.c code was added in response to concerns that the prior random32.c was too deterministic. Out of fears that random.c was (at the time) too slow, this code was anonymously contributed. Then out of that emerged a kind of shadow entropy gathering system, with its own tentacles throughout various net code, added willy nilly. Stop👏making👏bespoke👏random👏number👏generators👏. Fortunately, recent advances in random.c mean that we can stop playing with this sketchiness, and just use get_random_u32(), which is now fast enough. In micro benchmarks using RDPMC, I'm seeing the same median cycle count between the two functions, with the mean being _slightly_ higher due to batches refilling (which we can optimize further need be). However, when doing *real* benchmarks of the net functions that actually use these random numbers, the mean cycles actually *decreased* slightly (with the median still staying the same), likely because the additional prandom code means icache misses and complexity, whereas random.c is generally already being used by something else nearby. The biggest benefit of this is that there are many users of prandom who probably should be using cryptographically secure random numbers. This makes all of those accidental cases become secure by just flipping a switch. Later on, we can do a tree-wide cleanup to remove the static inline wrapper functions that this commit adds. There are also some low-ish hanging fruits for making this even faster in the future: a get_random_u16() function for use in the networking stack will give a 2x performance boost there, using SIMD for ChaCha20 will let us compute 4 or 8 or 16 blocks of output in parallel, instead of just one, giving us large buffers for cheap, and introducing a get_random_*_bh() function that assumes irqs are already disabled will shave off a few cycles for ordinary calls. These are things we can chip away at down the road. Acked-by: Jakub Kicinski Acked-by: Theodore Ts'o Signed-off-by: Jason A. Donenfeld

random: replace custom notifier chain with standard one

2022-03-13T01:00:56+00:00

We previously rolled our own randomness readiness notifier, which only has two users in the whole kernel. Replace this with a more standard atomic notifier block that serves the same purpose with less code. Also unexport the symbols, because no modules use it, only unconditional builtins. The only drawback is that it's possible for a notification handler returning the "stop" code to prevent further processing, but given that there are only two users, and that we're unexporting this anyway, that doesn't seem like a significant drawback for the simplification we receive here. Cc: Greg Kroah-Hartman Cc: Theodore Ts'o Reviewed-by: Dominik Brodowski Signed-off-by: Jason A. Donenfeld

random: remove unused tracepoints

2022-02-21T20:14:00+00:00

These explicit tracepoints aren't really used and show sign of aging. It's work to keep these up to date, and before I attempted to keep them up to date, they weren't up to date, which indicates that they're not really used. These days there are better ways of introspecting anyway. Cc: Theodore Ts'o Reviewed-by: Dominik Brodowski Reviewed-by: Eric Biggers Signed-off-by: Jason A. Donenfeld

mm: don't include in

2021-10-18T12:17:01+00:00

blk-cgroup.h pulls in blkdev.h and thus pretty much all the block headers. Break this dependency chain by turning wbc_blkcg_css into a macro and dropping the blk-cgroup.h include. Signed-off-by: Christoph Hellwig Reviewed-by: Johannes Thumshirn Link: https://lore.kernel.org/r/20210920123328.1399408-2-hch@lst.de Signed-off-by: Jens Axboe

random32: add a selftest for the prandom32 code

2020-10-24T18:21:57+00:00

Given that this code is new, let's add a selftest for it as well. It doesn't rely on fixed sets, instead it picks 1024 numbers and verifies that they're not more correlated than desired. Link: https://lore.kernel.org/netdev/20200808152628.GA27941@SDF.ORG/ Cc: George Spelvin Cc: Amit Klein Cc: Eric Dumazet Cc: "Jason A. Donenfeld" Cc: Andy Lutomirski Cc: Kees Cook Cc: Thomas Gleixner Cc: Peter Zijlstra Cc: Linus Torvalds Cc: tytso@mit.edu Cc: Florian Westphal Cc: Marc Plumb Signed-off-by: Willy Tarreau