From d04ac3a54895a36998e3f1da27c2ce33f7a80c5a Mon Sep 17 00:00:00 2001 From: Dmitry Vyukov Date: Mon, 3 Apr 2023 07:45:09 +0200 Subject: sys/linux: add syz_pkey_set syscalls The syscall sets PKRU register which is part of protection keys (pkey). --- executor/common_linux.h | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) (limited to 'executor/common_linux.h') diff --git a/executor/common_linux.h b/executor/common_linux.h index e53a908ab..a2736624a 100644 --- a/executor/common_linux.h +++ b/executor/common_linux.h @@ -5547,3 +5547,27 @@ static long syz_clone3(volatile long a0, volatile long a1) } #endif + +#if SYZ_EXECUTOR || __NR_syz_pkey_set +// syz_pkey_set(key pkey, val flags[pkey_flags]) +static long syz_pkey_set(volatile long pkey, volatile long val) +{ +#if GOARCH_amd64 || GOARCH_386 + uint32 eax = 0; + uint32 ecx = 0; + asm volatile("rdpkru" + : "=a"(eax) + : "c"(ecx) + : "edx"); + // PKRU register contains 2 bits per key. + // Max number of keys is 16. + // Clear old bits for the key: + eax &= ~(3 << ((pkey % 16) * 2)); + // Set new bits for the key: + eax |= (val & 3) << ((pkey % 16) * 2); + uint32 edx = 0; + asm volatile("wrpkru" ::"a"(eax), "c"(ecx), "d"(edx)); +#endif + return 0; +} +#endif -- cgit mrf-deployment