#include "mem_user.h"
#include "ptrace_user.h"
#include "registers.h"
+#include "skas.h"
#include "skas_ptrace.h"
-static int ptrace_child(void *arg)
+static void ptrace_child(void)
{
int ret;
+ /* Calling os_getpid because some libcs cached getpid incorrectly */
int pid = os_getpid(), ppid = getppid();
int sc_result;
- change_sig(SIGWINCH, 0);
- if (ptrace(PTRACE_TRACEME, 0, 0, 0) < 0) {
+ if (change_sig(SIGWINCH, 0) < 0 ||
+ ptrace(PTRACE_TRACEME, 0, 0, 0) < 0) {
perror("ptrace");
- os_kill_process(pid, 0);
+ kill(pid, SIGKILL);
}
kill(pid, SIGSTOP);
* the UML code itself.
*/
ret = 2;
- _exit(ret);
+
+ exit(ret);
}
-static void fatal_perror(char *str)
+static void fatal_perror(const char *str)
{
perror(str);
exit(1);
va_list list;
va_start(list, fmt);
- vprintf(fmt, list);
+ vfprintf(stderr, fmt, list);
va_end(list);
- fflush(stdout);
exit(1);
}
va_list list;
va_start(list, fmt);
- vprintf(fmt, list);
+ vfprintf(stderr, fmt, list);
va_end(list);
- fflush(stdout);
}
-static int start_ptraced_child(void **stack_out)
+static int start_ptraced_child(void)
{
- void *stack;
- unsigned long sp;
int pid, n, status;
- stack = mmap(NULL, UM_KERN_PAGE_SIZE,
- PROT_READ | PROT_WRITE | PROT_EXEC,
- MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
- if (stack == MAP_FAILED)
- fatal_perror("check_ptrace : mmap failed");
-
- sp = (unsigned long) stack + UM_KERN_PAGE_SIZE - sizeof(void *);
- pid = clone(ptrace_child, (void *) sp, SIGCHLD, NULL);
- if (pid < 0)
- fatal_perror("start_ptraced_child : clone failed");
+ pid = fork();
+ if (pid == 0)
+ ptrace_child();
+ else if (pid < 0)
+ fatal_perror("start_ptraced_child : fork failed");
CATCH_EINTR(n = waitpid(pid, &status, WUNTRACED));
if (n < 0)
- fatal_perror("check_ptrace : clone failed");
+ fatal_perror("check_ptrace : waitpid failed");
if (!WIFSTOPPED(status) || (WSTOPSIG(status) != SIGSTOP))
fatal("check_ptrace : expected SIGSTOP, got status = %d",
status);
- *stack_out = stack;
return pid;
}
* So only for SYSEMU features we test mustpanic, while normal host features
* must work anyway!
*/
-static int stop_ptraced_child(int pid, void *stack, int exitcode,
- int mustexit)
+static int stop_ptraced_child(int pid, int exitcode, int mustexit)
{
int status, n, ret = 0;
ret = -1;
}
- if (munmap(stack, UM_KERN_PAGE_SIZE) < 0)
- fatal_perror("check_ptrace : munmap failed");
return ret;
}
/* Changed only during early boot */
-int ptrace_faultinfo = 1;
-int ptrace_ldt = 1;
-int proc_mm = 1;
-int skas_needs_stub = 0;
+int ptrace_faultinfo;
+static int disable_ptrace_faultinfo;
+
+int ptrace_ldt;
+static int disable_ptrace_ldt;
+
+int proc_mm;
+static int disable_proc_mm;
+
+int have_switch_mm;
+static int disable_switch_mm;
+
+int skas_needs_stub;
static int __init skas0_cmd_param(char *str, int* add)
{
- ptrace_faultinfo = proc_mm = 0;
+ disable_ptrace_faultinfo = 1;
+ disable_ptrace_ldt = 1;
+ disable_proc_mm = 1;
+ disable_switch_mm = 1;
+
return 0;
}
__attribute__((alias("skas0_cmd_param")));
__uml_setup("skas0", skas0_cmd_param,
- "skas0\n"
- " Disables SKAS3 usage, so that SKAS0 is used, unless \n"
- " you specify mode=tt.\n\n");
+"skas0\n"
+" Disables SKAS3 and SKAS4 usage, so that SKAS0 is used\n\n");
__uml_setup("mode=skas0", mode_skas0_cmd_param,
- "mode=skas0\n"
- " Disables SKAS3 usage, so that SKAS0 is used, unless you \n"
- " specify mode=tt. Note that this was recently added - on \n"
- " older kernels you must use simply \"skas0\".\n\n");
+"mode=skas0\n"
+" Disables SKAS3 and SKAS4 usage, so that SKAS0 is used.\n\n");
/* Changed only during early boot */
static int force_sysemu_disabled = 0;
static void __init check_sysemu(void)
{
- void *stack;
unsigned long regs[MAX_REG_NR];
int pid, n, status, count=0;
non_fatal("Checking syscall emulation patch for ptrace...");
sysemu_supported = 0;
- pid = start_ptraced_child(&stack);
+ pid = start_ptraced_child();
if (ptrace(PTRACE_SYSEMU, pid, 0, 0) < 0)
goto fail;
goto fail;
}
- if (stop_ptraced_child(pid, stack, 0, 0) < 0)
+ if (stop_ptraced_child(pid, 0, 0) < 0)
goto fail_stopped;
sysemu_supported = 1;
set_using_sysemu(!force_sysemu_disabled);
non_fatal("Checking advanced syscall emulation patch for ptrace...");
- pid = start_ptraced_child(&stack);
+ pid = start_ptraced_child();
if ((ptrace(PTRACE_OLDSETOPTIONS, pid, 0,
(void *) PTRACE_O_TRACESYSGOOD) < 0))
fatal("check_ptrace : expected SIGTRAP or "
"(SIGTRAP | 0x80), got status = %d", status);
}
- if (stop_ptraced_child(pid, stack, 0, 0) < 0)
+ if (stop_ptraced_child(pid, 0, 0) < 0)
goto fail_stopped;
sysemu_supported = 2;
return;
fail:
- stop_ptraced_child(pid, stack, 1, 0);
+ stop_ptraced_child(pid, 1, 0);
fail_stopped:
non_fatal("missing\n");
}
static void __init check_ptrace(void)
{
- void *stack;
int pid, syscall, n, status;
non_fatal("Checking that ptrace can change system call numbers...");
- pid = start_ptraced_child(&stack);
+ pid = start_ptraced_child();
if ((ptrace(PTRACE_OLDSETOPTIONS, pid, 0,
(void *) PTRACE_O_TRACESYSGOOD) < 0))
break;
}
}
- stop_ptraced_child(pid, stack, 0, 1);
+ stop_ptraced_child(pid, 0, 1);
non_fatal("OK\n");
check_sysemu();
}
void __init os_early_checks(void)
{
+ int pid;
+
/* Print out the core dump limits early */
check_coredump_limit();
* kernel is running.
*/
check_tmpexec();
+
+ pid = start_ptraced_child();
+ if (init_registers(pid))
+ fatal("Failed to initialize default registers");
+ stop_ptraced_child(pid, 1, 1);
}
static int __init noprocmm_cmd_param(char *str, int* add)
{
- proc_mm = 0;
+ disable_proc_mm = 1;
return 0;
}
static int __init noptracefaultinfo_cmd_param(char *str, int* add)
{
- ptrace_faultinfo = 0;
+ disable_ptrace_faultinfo = 1;
return 0;
}
static int __init noptraceldt_cmd_param(char *str, int* add)
{
- ptrace_ldt = 0;
+ disable_ptrace_ldt = 1;
return 0;
}
static inline void check_skas3_ptrace_faultinfo(void)
{
struct ptrace_faultinfo fi;
- void *stack;
int pid, n;
non_fatal(" - PTRACE_FAULTINFO...");
- pid = start_ptraced_child(&stack);
+ pid = start_ptraced_child();
n = ptrace(PTRACE_FAULTINFO, pid, 0, &fi);
if (n < 0) {
- ptrace_faultinfo = 0;
if (errno == EIO)
non_fatal("not found\n");
else
perror("not found");
- }
+ } else if (disable_ptrace_faultinfo)
+ non_fatal("found but disabled on command line\n");
else {
- if (!ptrace_faultinfo)
- non_fatal("found but disabled on command line\n");
- else
- non_fatal("found\n");
+ ptrace_faultinfo = 1;
+ non_fatal("found\n");
}
- init_registers(pid);
- stop_ptraced_child(pid, stack, 1, 1);
+ stop_ptraced_child(pid, 1, 1);
}
static inline void check_skas3_ptrace_ldt(void)
{
#ifdef PTRACE_LDT
- void *stack;
int pid, n;
unsigned char ldtbuf[40];
struct ptrace_ldt ldt_op = (struct ptrace_ldt) {
.bytecount = sizeof(ldtbuf)};
non_fatal(" - PTRACE_LDT...");
- pid = start_ptraced_child(&stack);
+ pid = start_ptraced_child();
n = ptrace(PTRACE_LDT, pid, 0, (unsigned long) &ldt_op);
if (n < 0) {
if (errno == EIO)
non_fatal("not found\n");
- else {
+ else
perror("not found");
- }
- ptrace_ldt = 0;
- }
+ } else if (disable_ptrace_ldt)
+ non_fatal("found, but use is disabled\n");
else {
- if (ptrace_ldt)
- non_fatal("found\n");
- else
- non_fatal("found, but use is disabled\n");
+ ptrace_ldt = 1;
+ non_fatal("found\n");
}
- stop_ptraced_child(pid, stack, 1, 1);
-#else
- /* PTRACE_LDT might be disabled via cmdline option.
- * We want to override this, else we might use the stub
- * without real need
- */
- ptrace_ldt = 1;
+ stop_ptraced_child(pid, 1, 1);
#endif
}
static inline void check_skas3_proc_mm(void)
{
non_fatal(" - /proc/mm...");
- if (access("/proc/mm", W_OK) < 0) {
- proc_mm = 0;
+ if (access("/proc/mm", W_OK) < 0)
perror("not found");
- }
- else if (!proc_mm)
+ else if (disable_proc_mm)
non_fatal("found but disabled on command line\n");
- else non_fatal("found\n");
+ else {
+ proc_mm = 1;
+ non_fatal("found\n");
+ }
}
-int can_do_skas(void)
+void can_do_skas(void)
{
non_fatal("Checking for the skas3 patch in the host:\n");
if (!proc_mm || !ptrace_faultinfo || !ptrace_ldt)
skas_needs_stub = 1;
-
- return 1;
}
int __init parse_iomem(char *str, int *add)
driver = str;
file = strchr(str,',');
if (file == NULL) {
- printf("parse_iomem : failed to parse iomem\n");
+ fprintf(stderr, "parse_iomem : failed to parse iomem\n");
goto out;
}
*file = '\0';
file++;
fd = open(file, O_RDWR, 0);
if (fd < 0) {
- os_print_error(fd, "parse_iomem - Couldn't open io file");
+ perror("parse_iomem - Couldn't open io file");
goto out;
}