all: don't use global PRNG state from math/rand #10575
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Some packages initialize the global PRNG state in package math/rand using the Seed func in their init func. This might influence the PRNG state for other packages by solely loaded the former package. Switch to use a per package rand.Rand instance which can then be safely initialized and used in each package. This also makes it more obvious in tests which PRNG state is explicitly seeded to a known value. Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
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Since Go 1.20 the top-level math/rand functions are auto-seeded by default, see https://go.dev/doc/go1.20#library and golang/go#54880. They also use the runtime's lock-free fastrand64 function when 1. Seed has not been called and 2. GODEBUG=randautoseed=0 is not used, see golang/go#49892. This allows to drop SafeRand and use the global source again. SafeRand was introduced in commit fac5dde ("rand: add and use concurrency-safe PRNG source") to fix #10988 by providing a concurrency-safe PRNG source other than the global math/rand source which couldn't be used at the time because it can't be interfered with from unrelated packages by means of calling rand.Seed, see #10575. rand.Seed is deprecated since GO 1.20 and per the paragraph above the global source is seeded by default. This makes it unlikely that packages would interfere with the global PRNG state anymore and the top-level math/rand functions are safe to use again. Signed-off-by: Tobias Klauser <tobias@cilium.io>
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Since Go 1.20 the top-level math/rand functions are auto-seeded by default, see https://go.dev/doc/go1.20#library and golang/go#54880. They also use the runtime's lock-free fastrand64 function when 1. Seed has not been called and 2. GODEBUG=randautoseed=0 is not used, see golang/go#49892. This allows to drop SafeRand and use the global source again. SafeRand was originally introduced in commit fac5dde ("rand: add and use concurrency-safe PRNG source") to fix #10988 by providing a concurrency-safe PRNG source other than the global math/rand source which could be used at the time because it can't be interfered with from unrelated packages by means of calling rand.Seed, see #10575. rand.Seed is deprecated since Go 1.20 and per the paragraph above the global source is seeded by default. This makes it unlikely that packages would interfere with the global PRNG state anymore and the top-level math/rand functions are safe to use again. Signed-off-by: Tobias Klauser <tobias@cilium.io>
tklauser
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Dec 8, 2023
Since Go 1.20 the top-level math/rand functions are auto-seeded by default, see https://go.dev/doc/go1.20#library and golang/go#54880. They also use the runtime's lock-free fastrand64 function when 1. Seed has not been called and 2. GODEBUG=randautoseed=0 is not used, see golang/go#49892. This allows to drop SafeRand and use the global source again. SafeRand was originally introduced in commit fac5dde ("rand: add and use concurrency-safe PRNG source") to fix #10988 by providing a concurrency-safe PRNG source other than the global math/rand source which could be used at the time because it can't be interfered with from unrelated packages by means of calling rand.Seed, see #10575. rand.Seed is deprecated since Go 1.20 and per the paragraph above the global source is seeded by default. This makes it unlikely that packages would interfere with the global PRNG state anymore and the top-level math/rand functions are safe to use again. Signed-off-by: Tobias Klauser <tobias@cilium.io>
tklauser
added a commit
that referenced
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Dec 8, 2023
Since Go 1.20 the top-level math/rand functions are auto-seeded by default, see https://go.dev/doc/go1.20#library and golang/go#54880. They also use the runtime's lock-free fastrand64 function when 1. Seed has not been called and 2. GODEBUG=randautoseed=0 is not used, see golang/go#49892. This allows to drop SafeRand and use the global source again. SafeRand was originally introduced in commit fac5dde ("rand: add and use concurrency-safe PRNG source") to fix #10988 by providing a concurrency-safe PRNG source other than the global math/rand source which could be used at the time because it can't be interfered with from unrelated packages by means of calling rand.Seed, see #10575. rand.Seed is deprecated since Go 1.20 and per the paragraph above the global source is seeded by default. This makes it unlikely that packages would interfere with the global PRNG state anymore and the top-level math/rand functions are safe to use again. Signed-off-by: Tobias Klauser <tobias@cilium.io>
tklauser
added a commit
that referenced
this pull request
Dec 8, 2023
Since Go 1.20 the top-level math/rand functions are auto-seeded by default, see https://go.dev/doc/go1.20#library and golang/go#54880. They also use the runtime's lock-free fastrand64 function when 1. Seed has not been called and 2. GODEBUG=randautoseed=0 is not used, see golang/go#49892. This allows to drop SafeRand and use the global source again. SafeRand was originally introduced in commit fac5dde ("rand: add and use concurrency-safe PRNG source") to fix #10988 by providing a concurrency-safe PRNG source other than the global math/rand source which could be used at the time because it can't be interfered with from unrelated packages by means of calling rand.Seed, see #10575. rand.Seed is deprecated since Go 1.20 and per the paragraph above the global source is seeded by default. This makes it unlikely that packages would interfere with the global PRNG state anymore and the top-level math/rand functions are safe to use again. Signed-off-by: Tobias Klauser <tobias@cilium.io>
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Some packages initialize the global PRNG state in package math/rand
using the Seed func in their init func. This might influence the PRNG
state for other packages by solely loaded the former package.
Switch to use a per package rand.Rand instance which can then be safely
initialized and used in each package. This also makes it more obvious in
tests which PRNG state is explicitly seeded to a known value.
This change is