~hc/RK356X_SDK_RELEASE.git

..	..	@@ -1,15 +1,7 @@
	1	+// SPDX-License-Identifier: GPL-2.0-only
1	2	/*
2	3	* syscall_arg_fault.c - tests faults 32-bit fast syscall stack args
3	4	* Copyright (c) 2015 Andrew Lutomirski
4		- *
5		- * This program is free software; you can redistribute it and/or modify
6		- * it under the terms and conditions of the GNU General Public License,
7		- * version 2, as published by the Free Software Foundation.
8		- *
9		- * This program is distributed in the hope it will be useful, but
10		- * WITHOUT ANY WARRANTY; without even the implied warranty of
11		- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12		- * General Public License for more details.
13	5	*/
14	6
15	7	#define _GNU_SOURCE
..	..	@@ -22,6 +14,8 @@
22	14	#include <err.h>
23	15	#include <setjmp.h>
24	16	#include <errno.h>
	17	+
	18	+#include "helpers.h"
25	19
26	20	/* Our sigaltstack scratch space. */
27	21	static unsigned char altstack_data[SIGSTKSZ];
..	..	@@ -43,13 +37,23 @@
43	37
44	38	static volatile sig_atomic_t n_errs;
45	39
46		-static void sigsegv(int sig, siginfo_t info, void ctx_void)
	40	+#ifdef __x86_64__
	41	+#define REG_AX REG_RAX
	42	+#define REG_IP REG_RIP
	43	+#else
	44	+#define REG_AX REG_EAX
	45	+#define REG_IP REG_EIP
	46	+#endif
	47	+
	48	+static void sigsegv_or_sigbus(int sig, siginfo_t info, void ctx_void)
47	49	{
48	50	ucontext_t ctx = (ucontext_t)ctx_void;
	51	+ long ax = (long)ctx->uc_mcontext.gregs[REG_AX];
49	52
50		- if (ctx->uc_mcontext.gregs[REG_EAX] != -EFAULT) {
51		- printf("[FAIL]\tAX had the wrong value: 0x%x\n",
52		- ctx->uc_mcontext.gregs[REG_EAX]);
	53	+ if (ax != -EFAULT && ax != -ENOSYS) {
	54	+ printf("[FAIL]\tAX had the wrong value: 0x%lx\n",
	55	+ (unsigned long)ax);
	56	+ printf("\tIP = 0x%lx\n", (unsigned long)ctx->uc_mcontext.gregs[REG_IP]);
53	57	n_errs++;
54	58	} else {
55	59	printf("[OK]\tSeems okay\n");
..	..	@@ -58,9 +62,42 @@
58	62	siglongjmp(jmpbuf, 1);
59	63	}
60	64
	65	+static volatile sig_atomic_t sigtrap_consecutive_syscalls;
	66	+
	67	+static void sigtrap(int sig, siginfo_t info, void ctx_void)
	68	+{
	69	+ /*
	70	+ * KVM has some bugs that can cause us to stop making progress.
	71	+ * detect them and complain, but don't infinite loop or fail the
	72	+ * test.
	73	+ */
	74	+
	75	+ ucontext_t ctx = (ucontext_t)ctx_void;
	76	+ unsigned short ip = (unsigned short )ctx->uc_mcontext.gregs[REG_IP];
	77	+
	78	+ if (ip == 0x340f \|\| ip == 0x050f) {
	79	+ /* The trap was on SYSCALL or SYSENTER */
	80	+ sigtrap_consecutive_syscalls++;
	81	+ if (sigtrap_consecutive_syscalls > 3) {
	82	+ printf("[WARN]\tGot stuck single-stepping -- you probably have a KVM bug\n");
	83	+ siglongjmp(jmpbuf, 1);
	84	+ }
	85	+ } else {
	86	+ sigtrap_consecutive_syscalls = 0;
	87	+ }
	88	+}
	89	+
61	90	static void sigill(int sig, siginfo_t info, void ctx_void)
62	91	{
63		- printf("[SKIP]\tIllegal instruction\n");
	92	+ ucontext_t ctx = (ucontext_t)ctx_void;
	93	+ unsigned short ip = (unsigned short )ctx->uc_mcontext.gregs[REG_IP];
	94	+
	95	+ if (*ip == 0x0b0f) {
	96	+ /* one of the ud2 instructions faulted */
	97	+ printf("[OK]\tSYSCALL returned normally\n");
	98	+ } else {
	99	+ printf("[SKIP]\tIllegal instruction\n");
	100	+ }
64	101	siglongjmp(jmpbuf, 1);
65	102	}
66	103
..	..	@@ -73,7 +110,13 @@
73	110	if (sigaltstack(&stack, NULL) != 0)
74	111	err(1, "sigaltstack");
75	112
76		- sethandler(SIGSEGV, sigsegv, SA_ONSTACK);
	113	+ sethandler(SIGSEGV, sigsegv_or_sigbus, SA_ONSTACK);
	114	+ /*
	115	+ * The actual exception can vary. On Atom CPUs, we get #SS
	116	+ * instead of #PF when the vDSO fails to access the stack when
	117	+ * ESP is too close to 2^32, and #SS causes SIGBUS.
	118	+ */
	119	+ sethandler(SIGBUS, sigsegv_or_sigbus, SA_ONSTACK);
77	120	sethandler(SIGILL, sigill, SA_ONSTACK);
78	121
79	122	/*
..	..	@@ -122,9 +165,73 @@
122	165	"movl $-1, %%ebp\n\t"
123	166	"movl $-1, %%esp\n\t"
124	167	"syscall\n\t"
125		- "pushl $0" /* make sure we segfault cleanly */
	168	+ "ud2" /* make sure we recover cleanly */
126	169	: : : "memory", "flags");
127	170	}
128	171
	172	+ printf("[RUN]\tSYSENTER with TF and invalid state\n");
	173	+ sethandler(SIGTRAP, sigtrap, SA_ONSTACK);
	174	+
	175	+ if (sigsetjmp(jmpbuf, 1) == 0) {
	176	+ sigtrap_consecutive_syscalls = 0;
	177	+ set_eflags(get_eflags() \| X86_EFLAGS_TF);
	178	+ asm volatile (
	179	+ "movl $-1, %%eax\n\t"
	180	+ "movl $-1, %%ebx\n\t"
	181	+ "movl $-1, %%ecx\n\t"
	182	+ "movl $-1, %%edx\n\t"
	183	+ "movl $-1, %%esi\n\t"
	184	+ "movl $-1, %%edi\n\t"
	185	+ "movl $-1, %%ebp\n\t"
	186	+ "movl $-1, %%esp\n\t"
	187	+ "sysenter"
	188	+ : : : "memory", "flags");
	189	+ }
	190	+ set_eflags(get_eflags() & ~X86_EFLAGS_TF);
	191	+
	192	+ printf("[RUN]\tSYSCALL with TF and invalid state\n");
	193	+ if (sigsetjmp(jmpbuf, 1) == 0) {
	194	+ sigtrap_consecutive_syscalls = 0;
	195	+ set_eflags(get_eflags() \| X86_EFLAGS_TF);
	196	+ asm volatile (
	197	+ "movl $-1, %%eax\n\t"
	198	+ "movl $-1, %%ebx\n\t"
	199	+ "movl $-1, %%ecx\n\t"
	200	+ "movl $-1, %%edx\n\t"
	201	+ "movl $-1, %%esi\n\t"
	202	+ "movl $-1, %%edi\n\t"
	203	+ "movl $-1, %%ebp\n\t"
	204	+ "movl $-1, %%esp\n\t"
	205	+ "syscall\n\t"
	206	+ "ud2" /* make sure we recover cleanly */
	207	+ : : : "memory", "flags");
	208	+ }
	209	+ set_eflags(get_eflags() & ~X86_EFLAGS_TF);
	210	+
	211	+#ifdef __x86_64__
	212	+ printf("[RUN]\tSYSENTER with TF, invalid state, and GSBASE < 0\n");
	213	+
	214	+ if (sigsetjmp(jmpbuf, 1) == 0) {
	215	+ sigtrap_consecutive_syscalls = 0;
	216	+
	217	+ asm volatile ("wrgsbase %%rax\n\t"
	218	+ :: "a" (0xffffffffffff0000UL));
	219	+
	220	+ set_eflags(get_eflags() \| X86_EFLAGS_TF);
	221	+ asm volatile (
	222	+ "movl $-1, %%eax\n\t"
	223	+ "movl $-1, %%ebx\n\t"
	224	+ "movl $-1, %%ecx\n\t"
	225	+ "movl $-1, %%edx\n\t"
	226	+ "movl $-1, %%esi\n\t"
	227	+ "movl $-1, %%edi\n\t"
	228	+ "movl $-1, %%ebp\n\t"
	229	+ "movl $-1, %%esp\n\t"
	230	+ "sysenter"
	231	+ : : : "memory", "flags");
	232	+ }
	233	+ set_eflags(get_eflags() & ~X86_EFLAGS_TF);
	234	+#endif
	235	+
129	236	return 0;
130	237	}