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Diffstat (limited to 'arch/um/os-Linux/start_up.c')
-rw-r--r--arch/um/os-Linux/start_up.c106
1 files changed, 57 insertions, 49 deletions
diff --git a/arch/um/os-Linux/start_up.c b/arch/um/os-Linux/start_up.c
index 997d01944f91..183db26d01bf 100644
--- a/arch/um/os-Linux/start_up.c
+++ b/arch/um/os-Linux/start_up.c
@@ -23,6 +23,7 @@
#include "mem_user.h"
#include "ptrace_user.h"
#include "registers.h"
+#include "skas.h"
#include "skas_ptrace.h"
static void ptrace_child(void)
@@ -120,8 +121,10 @@ static int stop_ptraced_child(int pid, int exitcode, int mustexit)
{
int status, n, ret = 0;
- if (ptrace(PTRACE_CONT, pid, 0, 0) < 0)
- fatal_perror("stop_ptraced_child : ptrace failed");
+ if (ptrace(PTRACE_CONT, pid, 0, 0) < 0) {
+ perror("stop_ptraced_child : ptrace failed");
+ return -1;
+ }
CATCH_EINTR(n = waitpid(pid, &status, 0));
if (!WIFEXITED(status) || (WEXITSTATUS(status) != exitcode)) {
int exit_with = WEXITSTATUS(status);
@@ -140,14 +143,27 @@ static int stop_ptraced_child(int pid, int exitcode, int mustexit)
}
/* 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;
}
@@ -157,15 +173,12 @@ static int __init mode_skas0_cmd_param(char *str, int* add)
__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;
@@ -201,7 +214,7 @@ static void __init check_sysemu(void)
if (n < 0)
fatal_perror("check_sysemu : wait failed");
if (!WIFSTOPPED(status) || (WSTOPSIG(status) != SIGTRAP))
- fatal("check_sysemu : expected SIGTRAP, got status = %d",
+ fatal("check_sysemu : expected SIGTRAP, got status = %d\n",
status);
if (ptrace(PTRACE_GETREGS, pid, 0, regs) < 0)
@@ -243,9 +256,11 @@ static void __init check_sysemu(void)
if (WIFSTOPPED(status) &&
(WSTOPSIG(status) == (SIGTRAP|0x80))) {
- if (!count)
- fatal("check_ptrace : SYSEMU_SINGLESTEP "
- "doesn't singlestep");
+ if (!count) {
+ non_fatal("check_ptrace : SYSEMU_SINGLESTEP "
+ "doesn't singlestep");
+ goto fail;
+ }
n = ptrace(PTRACE_POKEUSR, pid, PT_SYSCALL_RET_OFFSET,
os_getpid());
if (n < 0)
@@ -255,9 +270,12 @@ static void __init check_sysemu(void)
}
else if (WIFSTOPPED(status) && (WSTOPSIG(status) == SIGTRAP))
count++;
- else
- fatal("check_ptrace : expected SIGTRAP or "
- "(SIGTRAP | 0x80), got status = %d", status);
+ else {
+ non_fatal("check_ptrace : expected SIGTRAP or "
+ "(SIGTRAP | 0x80), got status = %d\n",
+ status);
+ goto fail;
+ }
}
if (stop_ptraced_child(pid, 0, 0) < 0)
goto fail_stopped;
@@ -360,7 +378,7 @@ void __init os_early_checks(void)
static int __init noprocmm_cmd_param(char *str, int* add)
{
- proc_mm = 0;
+ disable_proc_mm = 1;
return 0;
}
@@ -372,7 +390,7 @@ __uml_setup("noprocmm", noprocmm_cmd_param,
static int __init noptracefaultinfo_cmd_param(char *str, int* add)
{
- ptrace_faultinfo = 0;
+ disable_ptrace_faultinfo = 1;
return 0;
}
@@ -384,7 +402,7 @@ __uml_setup("noptracefaultinfo", noptracefaultinfo_cmd_param,
static int __init noptraceldt_cmd_param(char *str, int* add)
{
- ptrace_ldt = 0;
+ disable_ptrace_ldt = 1;
return 0;
}
@@ -404,17 +422,15 @@ static inline void check_skas3_ptrace_faultinfo(void)
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");
}
stop_ptraced_child(pid, 1, 1);
@@ -437,38 +453,30 @@ static inline void check_skas3_ptrace_ldt(void)
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, 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;
#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");
+ }
}
void can_do_skas(void)