Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
random: vDSO: avoid call to out of line memset()
With the current implementation, __cvdso_getrandom_data() calls
memset() on certain architectures, which is unexpected in the VDSO.
Rather than providing a memset(), simply rewrite opaque data
initialization to avoid memset().
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
authored by
Christophe Leroy
and committed by
Jason A. Donenfeld
b7bad082
81723e3a
+7
-5
+7
-5
lib/vdso/getrandom.c
+7
-5
lib/vdso/getrandom.c
···
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* Copyright (C) 2022-2024 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
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*/
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#include <linux/array_size.h>
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#include <linux/cache.h>
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#include <linux/kernel.h>
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#include <linux/time64.h>
···
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u32 counter[2] = { 0 };
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if (unlikely(opaque_len == ~0UL && !buffer && !len && !flags)) {
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-
*(struct vgetrandom_opaque_params *)opaque_state = (struct vgetrandom_opaque_params) {
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.size_of_opaque_state = sizeof(*state),
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.mmap_prot = PROT_READ | PROT_WRITE,
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.mmap_flags = MAP_DROPPABLE | MAP_ANONYMOUS
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};
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struct vgetrandom_opaque_params *params = opaque_state;
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params->size_of_opaque_state = sizeof(*state);
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params->mmap_prot = PROT_READ | PROT_WRITE;
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params->mmap_flags = MAP_DROPPABLE | MAP_ANONYMOUS;
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for (size_t i = 0; i < ARRAY_SIZE(params->reserved); ++i)
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params->reserved[i] = 0;
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return 0;
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}
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