um: pass siginfo to guest process

UML guest processes now get correct siginfo_t for SIGTRAP, SIGFPE,
SIGILL and SIGBUS. Specifically, si_addr and si_code are now correct
where previously they were si_addr = NULL and si_code = 128.

Signed-off-by: Martin Pärtel <martin.partel@gmail.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
This commit is contained in:
Martin Pärtel 2012-08-02 00:49:17 +02:00 committed by Richard Weinberger
parent d4afcba95f
commit d3c1cfcdb4
10 changed files with 71 additions and 34 deletions

View file

@ -60,7 +60,8 @@ extern unsigned long host_task_size;
extern int linux_main(int argc, char **argv);
extern void (*sig_info[])(int, struct uml_pt_regs *);
struct siginfo;
extern void (*sig_info[])(int, struct siginfo *si, struct uml_pt_regs *);
#endif

View file

@ -20,7 +20,8 @@ struct irq_fd {
enum { IRQ_READ, IRQ_WRITE };
extern void sigio_handler(int sig, struct uml_pt_regs *regs);
struct siginfo;
extern void sigio_handler(int sig, struct siginfo *unused_si, struct uml_pt_regs *regs);
extern void free_irq_by_fd(int fd);
extern void reactivate_fd(int fd, int irqnum);
extern void deactivate_fd(int fd, int irqnum);

View file

@ -9,6 +9,8 @@
#include "sysdep/ptrace.h"
#include "sysdep/faultinfo.h"
struct siginfo;
extern int uml_exitcode;
extern int ncpus;
@ -22,7 +24,7 @@ extern void free_stack(unsigned long stack, int order);
extern int do_signal(void);
extern void interrupt_end(void);
extern void relay_signal(int sig, struct uml_pt_regs *regs);
extern void relay_signal(int sig, struct siginfo *si, struct uml_pt_regs *regs);
extern unsigned long segv(struct faultinfo fi, unsigned long ip,
int is_user, struct uml_pt_regs *regs);
@ -33,9 +35,8 @@ extern unsigned int do_IRQ(int irq, struct uml_pt_regs *regs);
extern int smp_sigio_handler(void);
extern void initial_thread_cb(void (*proc)(void *), void *arg);
extern int is_syscall(unsigned long addr);
extern void timer_handler(int sig, struct uml_pt_regs *regs);
extern void timer_handler(int sig, struct uml_pt_regs *regs);
extern void timer_handler(int sig, struct siginfo *unused_si, struct uml_pt_regs *regs);
extern int start_uml(void);
extern void paging_init(void);
@ -59,9 +60,9 @@ extern unsigned long from_irq_stack(int nested);
extern void syscall_trace(struct uml_pt_regs *regs, int entryexit);
extern int singlestepping(void *t);
extern void segv_handler(int sig, struct uml_pt_regs *regs);
extern void bus_handler(int sig, struct uml_pt_regs *regs);
extern void winch(int sig, struct uml_pt_regs *regs);
extern void segv_handler(int sig, struct siginfo *unused_si, struct uml_pt_regs *regs);
extern void bus_handler(int sig, struct siginfo *si, struct uml_pt_regs *regs);
extern void winch(int sig, struct siginfo *unused_si, struct uml_pt_regs *regs);
extern void fatal_sigsegv(void) __attribute__ ((noreturn));

View file

@ -30,7 +30,7 @@ static struct irq_fd **last_irq_ptr = &active_fds;
extern void free_irqs(void);
void sigio_handler(int sig, struct uml_pt_regs *regs)
void sigio_handler(int sig, struct siginfo *unused_si, struct uml_pt_regs *regs)
{
struct irq_fd *irq_fd;
int n;

View file

@ -13,7 +13,7 @@
#include "kern_util.h"
#include "os.h"
void timer_handler(int sig, struct uml_pt_regs *regs)
void timer_handler(int sig, struct siginfo *unused_si, struct uml_pt_regs *regs)
{
unsigned long flags;

View file

@ -172,7 +172,7 @@ void fatal_sigsegv(void)
os_dump_core();
}
void segv_handler(int sig, struct uml_pt_regs *regs)
void segv_handler(int sig, struct siginfo *unused_si, struct uml_pt_regs *regs)
{
struct faultinfo * fi = UPT_FAULTINFO(regs);
@ -258,8 +258,11 @@ unsigned long segv(struct faultinfo fi, unsigned long ip, int is_user,
return 0;
}
void relay_signal(int sig, struct uml_pt_regs *regs)
void relay_signal(int sig, struct siginfo *si, struct uml_pt_regs *regs)
{
struct faultinfo *fi;
struct siginfo clean_si;
if (!UPT_IS_USER(regs)) {
if (sig == SIGBUS)
printk(KERN_ERR "Bus error - the host /dev/shm or /tmp "
@ -269,18 +272,40 @@ void relay_signal(int sig, struct uml_pt_regs *regs)
arch_examine_signal(sig, regs);
current->thread.arch.faultinfo = *UPT_FAULTINFO(regs);
force_sig(sig, current);
memset(&clean_si, 0, sizeof(clean_si));
clean_si.si_signo = si->si_signo;
clean_si.si_errno = si->si_errno;
clean_si.si_code = si->si_code;
switch (sig) {
case SIGILL:
case SIGFPE:
case SIGSEGV:
case SIGBUS:
case SIGTRAP:
fi = UPT_FAULTINFO(regs);
clean_si.si_addr = (void __user *) FAULT_ADDRESS(*fi);
current->thread.arch.faultinfo = *fi;
#ifdef __ARCH_SI_TRAPNO
clean_si.si_trapno = si->si_trapno;
#endif
break;
default:
printk(KERN_ERR "Attempted to relay unknown signal %d (si_code = %d)\n",
sig, si->si_code);
}
force_sig_info(sig, &clean_si, current);
}
void bus_handler(int sig, struct uml_pt_regs *regs)
void bus_handler(int sig, struct siginfo *si, struct uml_pt_regs *regs)
{
if (current->thread.fault_catcher != NULL)
UML_LONGJMP(current->thread.fault_catcher, 1);
else relay_signal(sig, regs);
else
relay_signal(sig, si, regs);
}
void winch(int sig, struct uml_pt_regs *regs)
void winch(int sig, struct siginfo *unused_si, struct uml_pt_regs *regs)
{
do_IRQ(WINCH_IRQ, regs);
}

View file

@ -1 +1 @@
void alarm_handler(int, mcontext_t *);
void alarm_handler(int sig, struct siginfo *unused_si, mcontext_t *mc);

View file

@ -13,8 +13,9 @@
#include "kern_util.h"
#include "os.h"
#include "sysdep/mcontext.h"
#include "internal.h"
void (*sig_info[NSIG])(int, struct uml_pt_regs *) = {
void (*sig_info[NSIG])(int, siginfo_t *, struct uml_pt_regs *) = {
[SIGTRAP] = relay_signal,
[SIGFPE] = relay_signal,
[SIGILL] = relay_signal,
@ -24,7 +25,7 @@ void (*sig_info[NSIG])(int, struct uml_pt_regs *) = {
[SIGIO] = sigio_handler,
[SIGVTALRM] = timer_handler };
static void sig_handler_common(int sig, mcontext_t *mc)
static void sig_handler_common(int sig, siginfo_t *si, mcontext_t *mc)
{
struct uml_pt_regs r;
int save_errno = errno;
@ -40,7 +41,7 @@ static void sig_handler_common(int sig, mcontext_t *mc)
if ((sig != SIGIO) && (sig != SIGWINCH) && (sig != SIGVTALRM))
unblock_signals();
(*sig_info[sig])(sig, &r);
(*sig_info[sig])(sig, si, &r);
errno = save_errno;
}
@ -60,7 +61,7 @@ static void sig_handler_common(int sig, mcontext_t *mc)
static int signals_enabled;
static unsigned int signals_pending;
void sig_handler(int sig, mcontext_t *mc)
void sig_handler(int sig, siginfo_t *si, mcontext_t *mc)
{
int enabled;
@ -72,7 +73,7 @@ void sig_handler(int sig, mcontext_t *mc)
block_signals();
sig_handler_common(sig, mc);
sig_handler_common(sig, si, mc);
set_signals(enabled);
}
@ -85,10 +86,10 @@ static void real_alarm_handler(mcontext_t *mc)
get_regs_from_mc(&regs, mc);
regs.is_user = 0;
unblock_signals();
timer_handler(SIGVTALRM, &regs);
timer_handler(SIGVTALRM, NULL, &regs);
}
void alarm_handler(int sig, mcontext_t *mc)
void alarm_handler(int sig, struct siginfo *unused_si, mcontext_t *mc)
{
int enabled;
@ -119,7 +120,7 @@ void set_sigstack(void *sig_stack, int size)
panic("enabling signal stack failed, errno = %d\n", errno);
}
static void (*handlers[_NSIG])(int sig, mcontext_t *mc) = {
static void (*handlers[_NSIG])(int sig, siginfo_t *si, mcontext_t *mc) = {
[SIGSEGV] = sig_handler,
[SIGBUS] = sig_handler,
[SIGILL] = sig_handler,
@ -132,7 +133,7 @@ static void (*handlers[_NSIG])(int sig, mcontext_t *mc) = {
};
static void hard_handler(int sig, siginfo_t *info, void *p)
static void hard_handler(int sig, siginfo_t *si, void *p)
{
struct ucontext *uc = p;
mcontext_t *mc = &uc->uc_mcontext;
@ -161,7 +162,7 @@ static void hard_handler(int sig, siginfo_t *info, void *p)
while ((sig = ffs(pending)) != 0){
sig--;
pending &= ~(1 << sig);
(*handlers[sig])(sig, mc);
(*handlers[sig])(sig, si, mc);
}
/*
@ -273,9 +274,12 @@ void unblock_signals(void)
* Deal with SIGIO first because the alarm handler might
* schedule, leaving the pending SIGIO stranded until we come
* back here.
*
* SIGIO's handler doesn't use siginfo or mcontext,
* so they can be NULL.
*/
if (save_pending & SIGIO_MASK)
sig_handler_common(SIGIO, NULL);
sig_handler_common(SIGIO, NULL, NULL);
if (save_pending & SIGVTALRM_MASK)
real_alarm_handler(NULL);

View file

@ -346,6 +346,7 @@ void userspace(struct uml_pt_regs *regs)
int err, status, op, pid = userspace_pid[0];
/* To prevent races if using_sysemu changes under us.*/
int local_using_sysemu;
siginfo_t si;
/* Handle any immediate reschedules or signals */
interrupt_end();
@ -407,13 +408,17 @@ void userspace(struct uml_pt_regs *regs)
if (WIFSTOPPED(status)) {
int sig = WSTOPSIG(status);
ptrace(PTRACE_GETSIGINFO, pid, 0, &si);
switch (sig) {
case SIGSEGV:
if (PTRACE_FULL_FAULTINFO ||
!ptrace_faultinfo) {
get_skas_faultinfo(pid,
&regs->faultinfo);
(*sig_info[SIGSEGV])(SIGSEGV, regs);
(*sig_info[SIGSEGV])(SIGSEGV, &si,
regs);
}
else handle_segv(pid, regs);
break;
@ -421,14 +426,14 @@ void userspace(struct uml_pt_regs *regs)
handle_trap(pid, regs, local_using_sysemu);
break;
case SIGTRAP:
relay_signal(SIGTRAP, regs);
relay_signal(SIGTRAP, &si, regs);
break;
case SIGVTALRM:
now = os_nsecs();
if (now < nsecs)
break;
block_signals();
(*sig_info[sig])(sig, regs);
(*sig_info[sig])(sig, &si, regs);
unblock_signals();
nsecs = timer.it_value.tv_sec *
UM_NSEC_PER_SEC +
@ -442,7 +447,7 @@ void userspace(struct uml_pt_regs *regs)
case SIGFPE:
case SIGWINCH:
block_signals();
(*sig_info[sig])(sig, regs);
(*sig_info[sig])(sig, &si, regs);
unblock_signals();
break;
default:

View file

@ -87,7 +87,7 @@ static int after_sleep_interval(struct timespec *ts)
static void deliver_alarm(void)
{
alarm_handler(SIGVTALRM, NULL);
alarm_handler(SIGVTALRM, NULL, NULL);
}
static unsigned long long sleep_time(unsigned long long nsecs)