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Diffstat (limited to 'arch/um/os-Linux/start_up.c')
-rw-r--r--arch/um/os-Linux/start_up.c154
1 files changed, 92 insertions, 62 deletions
diff --git a/arch/um/os-Linux/start_up.c b/arch/um/os-Linux/start_up.c
index 735d035a7f33..5178eba9afa5 100644
--- a/arch/um/os-Linux/start_up.c
+++ b/arch/um/os-Linux/start_up.c
@@ -73,6 +73,34 @@ static int ptrace_child(void *arg)
_exit(ret);
}
+static void fatal_perror(char *str)
+{
+ perror(str);
+ exit(1);
+}
+
+static void fatal(char *fmt, ...)
+{
+ va_list list;
+
+ va_start(list, fmt);
+ vprintf(fmt, list);
+ va_end(list);
+ fflush(stdout);
+
+ exit(1);
+}
+
+static void non_fatal(char *fmt, ...)
+{
+ va_list list;
+
+ va_start(list, fmt);
+ vprintf(fmt, list);
+ va_end(list);
+ fflush(stdout);
+}
+
static int start_ptraced_child(void **stack_out)
{
void *stack;
@@ -82,16 +110,16 @@ static int start_ptraced_child(void **stack_out)
stack = mmap(NULL, PAGE_SIZE, PROT_READ | PROT_WRITE | PROT_EXEC,
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
if(stack == MAP_FAILED)
- panic("check_ptrace : mmap failed, errno = %d", errno);
+ fatal_perror("check_ptrace : mmap failed");
sp = (unsigned long) stack + PAGE_SIZE - sizeof(void *);
pid = clone(ptrace_child, (void *) sp, SIGCHLD, NULL);
if(pid < 0)
- panic("start_ptraced_child : clone failed, errno = %d", errno);
+ fatal_perror("start_ptraced_child : clone failed");
CATCH_EINTR(n = waitpid(pid, &status, WUNTRACED));
if(n < 0)
- panic("check_ptrace : clone failed, errno = %d", errno);
+ fatal_perror("check_ptrace : clone failed");
if(!WIFSTOPPED(status) || (WSTOPSIG(status) != SIGSTOP))
- panic("check_ptrace : expected SIGSTOP, got status = %d",
+ fatal("check_ptrace : expected SIGSTOP, got status = %d",
status);
*stack_out = stack;
@@ -105,31 +133,30 @@ static int start_ptraced_child(void **stack_out)
* must work anyway!
*/
static int stop_ptraced_child(int pid, void *stack, int exitcode,
- int mustpanic)
+ int mustexit)
{
int status, n, ret = 0;
if(ptrace(PTRACE_CONT, pid, 0, 0) < 0)
- panic("check_ptrace : ptrace failed, errno = %d", errno);
+ fatal_perror("stop_ptraced_child : ptrace failed");
CATCH_EINTR(n = waitpid(pid, &status, 0));
if(!WIFEXITED(status) || (WEXITSTATUS(status) != exitcode)) {
int exit_with = WEXITSTATUS(status);
if (exit_with == 2)
- printf("check_ptrace : child exited with status 2. "
- "Serious trouble happening! Try updating your "
- "host skas patch!\nDisabling SYSEMU support.");
- printf("check_ptrace : child exited with exitcode %d, while "
- "expecting %d; status 0x%x", exit_with,
- exitcode, status);
- if (mustpanic)
- panic("\n");
- else
- printf("\n");
+ non_fatal("check_ptrace : child exited with status 2. "
+ "Serious trouble happening! Try updating "
+ "your host skas patch!\nDisabling SYSEMU "
+ "support.");
+ non_fatal("check_ptrace : child exited with exitcode %d, while "
+ "expecting %d; status 0x%x\n", exit_with,
+ exitcode, status);
+ if (mustexit)
+ exit(1);
ret = -1;
}
if(munmap(stack, PAGE_SIZE) < 0)
- panic("check_ptrace : munmap failed, errno = %d", errno);
+ fatal_perror("check_ptrace : munmap failed");
return ret;
}
@@ -184,7 +211,7 @@ static void __init check_sysemu(void)
void *stack;
int pid, n, status, count=0;
- printf("Checking syscall emulation patch for ptrace...");
+ non_fatal("Checking syscall emulation patch for ptrace...");
sysemu_supported = 0;
pid = start_ptraced_child(&stack);
@@ -193,31 +220,30 @@ static void __init check_sysemu(void)
CATCH_EINTR(n = waitpid(pid, &status, WUNTRACED));
if (n < 0)
- panic("check_sysemu : wait failed, errno = %d", errno);
+ fatal_perror("check_sysemu : wait failed");
if(!WIFSTOPPED(status) || (WSTOPSIG(status) != SIGTRAP))
- panic("check_sysemu : expected SIGTRAP, "
- "got status = %d", status);
+ fatal("check_sysemu : expected SIGTRAP, got status = %d",
+ status);
n = ptrace(PTRACE_POKEUSR, pid, PT_SYSCALL_RET_OFFSET,
os_getpid());
if(n < 0)
- panic("check_sysemu : failed to modify system "
- "call return, errno = %d", errno);
+ fatal_perror("check_sysemu : failed to modify system call "
+ "return");
if (stop_ptraced_child(pid, stack, 0, 0) < 0)
goto fail_stopped;
sysemu_supported = 1;
- printf("OK\n");
+ non_fatal("OK\n");
set_using_sysemu(!force_sysemu_disabled);
- printf("Checking advanced syscall emulation patch for ptrace...");
+ non_fatal("Checking advanced syscall emulation patch for ptrace...");
pid = start_ptraced_child(&stack);
- if(ptrace(PTRACE_OLDSETOPTIONS, pid, 0,
- (void *) PTRACE_O_TRACESYSGOOD) < 0)
- panic("check_ptrace: PTRACE_OLDSETOPTIONS failed, errno = %d",
- errno);
+ if((ptrace(PTRACE_OLDSETOPTIONS, pid, 0,
+ (void *) PTRACE_O_TRACESYSGOOD) < 0))
+ fatal_perror("check_ptrace: PTRACE_OLDSETOPTIONS failed");
while(1){
count++;
@@ -225,29 +251,30 @@ static void __init check_sysemu(void)
goto fail;
CATCH_EINTR(n = waitpid(pid, &status, WUNTRACED));
if(n < 0)
- panic("check_ptrace : wait failed, errno = %d", errno);
+ fatal_perror("check_ptrace : wait failed");
+
if(WIFSTOPPED(status) && (WSTOPSIG(status) == (SIGTRAP|0x80))){
if (!count)
- panic("check_ptrace : SYSEMU_SINGLESTEP "
+ fatal("check_ptrace : SYSEMU_SINGLESTEP "
"doesn't singlestep");
n = ptrace(PTRACE_POKEUSR, pid, PT_SYSCALL_RET_OFFSET,
os_getpid());
if(n < 0)
- panic("check_sysemu : failed to modify system "
- "call return, errno = %d", errno);
+ fatal_perror("check_sysemu : failed to modify "
+ "system call return");
break;
}
else if(WIFSTOPPED(status) && (WSTOPSIG(status) == SIGTRAP))
count++;
else
- panic("check_ptrace : expected SIGTRAP or "
- "(SIGTRAP|0x80), got status = %d", status);
+ fatal("check_ptrace : expected SIGTRAP or "
+ "(SIGTRAP | 0x80), got status = %d", status);
}
if (stop_ptraced_child(pid, stack, 0, 0) < 0)
goto fail_stopped;
sysemu_supported = 2;
- printf("OK\n");
+ non_fatal("OK\n");
if ( !force_sysemu_disabled )
set_using_sysemu(sysemu_supported);
@@ -256,7 +283,7 @@ static void __init check_sysemu(void)
fail:
stop_ptraced_child(pid, stack, 1, 0);
fail_stopped:
- printf("missing\n");
+ non_fatal("missing\n");
}
static void __init check_ptrace(void)
@@ -264,22 +291,25 @@ static void __init check_ptrace(void)
void *stack;
int pid, syscall, n, status;
- printf("Checking that ptrace can change system call numbers...");
+ non_fatal("Checking that ptrace can change system call numbers...");
pid = start_ptraced_child(&stack);
- if(ptrace(PTRACE_OLDSETOPTIONS, pid, 0, (void *)PTRACE_O_TRACESYSGOOD) < 0)
- panic("check_ptrace: PTRACE_OLDSETOPTIONS failed, errno = %d", errno);
+ if((ptrace(PTRACE_OLDSETOPTIONS, pid, 0,
+ (void *) PTRACE_O_TRACESYSGOOD) < 0))
+ fatal_perror("check_ptrace: PTRACE_OLDSETOPTIONS failed");
while(1){
if(ptrace(PTRACE_SYSCALL, pid, 0, 0) < 0)
- panic("check_ptrace : ptrace failed, errno = %d",
- errno);
+ fatal_perror("check_ptrace : ptrace failed");
+
CATCH_EINTR(n = waitpid(pid, &status, WUNTRACED));
if(n < 0)
- panic("check_ptrace : wait failed, errno = %d", errno);
- if(!WIFSTOPPED(status) || (WSTOPSIG(status) != (SIGTRAP|0x80)))
- panic("check_ptrace : expected (SIGTRAP|0x80), "
- "got status = %d", status);
+ fatal_perror("check_ptrace : wait failed");
+
+ if(!WIFSTOPPED(status) ||
+ (WSTOPSIG(status) != (SIGTRAP | 0x80)))
+ fatal("check_ptrace : expected (SIGTRAP|0x80), "
+ "got status = %d", status);
syscall = ptrace(PTRACE_PEEKUSR, pid, PT_SYSCALL_NR_OFFSET,
0);
@@ -287,13 +317,13 @@ static void __init check_ptrace(void)
n = ptrace(PTRACE_POKEUSR, pid, PT_SYSCALL_NR_OFFSET,
__NR_getppid);
if(n < 0)
- panic("check_ptrace : failed to modify system "
- "call, errno = %d", errno);
+ fatal_perror("check_ptrace : failed to modify "
+ "system call");
break;
}
}
stop_ptraced_child(pid, stack, 0, 1);
- printf("OK\n");
+ non_fatal("OK\n");
check_sysemu();
}
@@ -352,22 +382,22 @@ static inline void check_skas3_ptrace_faultinfo(void)
void *stack;
int pid, n;
- printf(" - PTRACE_FAULTINFO...");
+ non_fatal(" - PTRACE_FAULTINFO...");
pid = start_ptraced_child(&stack);
n = ptrace(PTRACE_FAULTINFO, pid, 0, &fi);
if (n < 0) {
ptrace_faultinfo = 0;
if(errno == EIO)
- printf("not found\n");
+ non_fatal("not found\n");
else
perror("not found");
}
else {
if (!ptrace_faultinfo)
- printf("found but disabled on command line\n");
+ non_fatal("found but disabled on command line\n");
else
- printf("found\n");
+ non_fatal("found\n");
}
init_registers(pid);
@@ -385,13 +415,13 @@ static inline void check_skas3_ptrace_ldt(void)
.ptr = ldtbuf,
.bytecount = sizeof(ldtbuf)};
- printf(" - PTRACE_LDT...");
+ non_fatal(" - PTRACE_LDT...");
pid = start_ptraced_child(&stack);
n = ptrace(PTRACE_LDT, pid, 0, (unsigned long) &ldt_op);
if (n < 0) {
if(errno == EIO)
- printf("not found\n");
+ non_fatal("not found\n");
else {
perror("not found");
}
@@ -399,9 +429,9 @@ static inline void check_skas3_ptrace_ldt(void)
}
else {
if(ptrace_ldt)
- printf("found\n");
+ non_fatal("found\n");
else
- printf("found, but use is disabled\n");
+ non_fatal("found, but use is disabled\n");
}
stop_ptraced_child(pid, stack, 1, 1);
@@ -416,22 +446,22 @@ static inline void check_skas3_ptrace_ldt(void)
static inline void check_skas3_proc_mm(void)
{
- printf(" - /proc/mm...");
+ non_fatal(" - /proc/mm...");
if (access("/proc/mm", W_OK) < 0) {
proc_mm = 0;
- printf("not found\n");
+ perror("not found");
}
else {
if (!proc_mm)
- printf("found but disabled on command line\n");
+ non_fatal("found but disabled on command line\n");
else
- printf("found\n");
+ non_fatal("found\n");
}
}
int can_do_skas(void)
{
- printf("Checking for the skas3 patch in the host:\n");
+ non_fatal("Checking for the skas3 patch in the host:\n");
check_skas3_proc_mm();
check_skas3_ptrace_faultinfo();
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