Signal handlers in UML guest processes now get correct siginfo_t fields
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.par...@gmail.com>
---
diff -uprN -X linux-3.4.1/Documentation/dontdiff -x config.c -x config.tmp
linux-3.4.1/arch/um/include/shared/as-layout.h
linux-3.4.1-mod/arch/um/include/shared/as-layout.h
--- linux-3.4.1/arch/um/include/shared/as-layout.h 2012-06-01
10:18:44.000000000 +0300
+++ linux-3.4.1-mod/arch/um/include/shared/as-layout.h 2012-06-07
18:48:21.469563959 +0300
@@ -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
diff -uprN -X linux-3.4.1/Documentation/dontdiff -x config.c -x config.tmp
linux-3.4.1/arch/um/include/shared/kern_util.h
linux-3.4.1-mod/arch/um/include/shared/kern_util.h
--- linux-3.4.1/arch/um/include/shared/kern_util.h 2012-06-01
10:18:44.000000000 +0300
+++ linux-3.4.1-mod/arch/um/include/shared/kern_util.h 2012-06-07
22:55:35.737822291 +0300
@@ -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 sta
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);
@@ -33,7 +35,6 @@ extern unsigned int do_IRQ(int irq, stru
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);
@@ -60,7 +61,7 @@ extern void syscall_trace(struct uml_pt_
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 bus_handler(int sig, struct siginfo *si, struct uml_pt_regs *regs);
extern void winch(int sig, struct uml_pt_regs *regs);
extern void fatal_sigsegv(void) __attribute__ ((noreturn));
diff -uprN -X linux-3.4.1/Documentation/dontdiff -x config.c -x config.tmp
linux-3.4.1/arch/um/kernel/trap.c linux-3.4.1-mod/arch/um/kernel/trap.c
--- linux-3.4.1/arch/um/kernel/trap.c 2012-06-01 10:18:44.000000000 +0300
+++ linux-3.4.1-mod/arch/um/kernel/trap.c 2012-06-07 23:30:11.905858447
+0300
@@ -244,7 +244,7 @@ unsigned long segv(struct faultinfo fi,
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)
{
if (!UPT_IS_USER(regs)) {
if (sig == SIGBUS)
@@ -256,14 +256,15 @@ void relay_signal(int sig, struct uml_pt
arch_examine_signal(sig, regs);
current->thread.arch.faultinfo = *UPT_FAULTINFO(regs);
- force_sig(sig, current);
+ force_sig_info(sig, 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)
diff -uprN -X linux-3.4.1/Documentation/dontdiff -x config.c -x config.tmp
linux-3.4.1/arch/um/os-Linux/signal.c linux-3.4.1-mod/arch/um/os-Linux/signal.c
--- linux-3.4.1/arch/um/os-Linux/signal.c 2012-06-01 10:18:44.000000000
+0300
+++ linux-3.4.1-mod/arch/um/os-Linux/signal.c 2012-06-07 23:32:13.693860567
+0300
@@ -13,18 +13,55 @@
#include "kern_util.h"
#include "os.h"
#include "sysdep/mcontext.h"
+#include "internal.h"
-void (*sig_info[NSIG])(int, struct uml_pt_regs *) = {
+static void winch_ignore_siginfo(int sig,
+ siginfo_t *si,
+ struct uml_pt_regs *regs)
+{
+ winch(sig, regs);
+}
+
+static void segv_handler_ignore_siginfo(int sig,
+ siginfo_t *si,
+ struct uml_pt_regs *regs)
+{
+ segv_handler(sig, regs);
+}
+
+static void sigio_handler_ignore_siginfo(int sig,
+ siginfo_t *si,
+ struct uml_pt_regs *regs)
+{
+ sigio_handler(sig, regs);
+}
+
+static void timer_handler_ignore_siginfo(int sig,
+ siginfo_t *si,
+ struct uml_pt_regs *regs)
+{
+ timer_handler(sig, regs);
+}
+
+static void alarm_handler_ignore_siginfo(int sig,
+ siginfo_t *si,
+ mcontext_t *mc)
+{
+ alarm_handler(sig, mc);
+}
+
+
+void (*sig_info[NSIG])(int, siginfo_t *, struct uml_pt_regs *) = {
[SIGTRAP] = relay_signal,
[SIGFPE] = relay_signal,
[SIGILL] = relay_signal,
- [SIGWINCH] = winch,
+ [SIGWINCH] = winch_ignore_siginfo,
[SIGBUS] = bus_handler,
- [SIGSEGV] = segv_handler,
- [SIGIO] = sigio_handler,
- [SIGVTALRM] = timer_handler };
+ [SIGSEGV] = segv_handler_ignore_siginfo,
+ [SIGIO] = sigio_handler_ignore_siginfo,
+ [SIGVTALRM] = timer_handler_ignore_siginfo };
-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 +77,7 @@ static void sig_handler_common(int sig,
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 +97,7 @@ static void sig_handler_common(int sig,
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 +109,7 @@ void sig_handler(int sig, mcontext_t *mc
block_signals();
- sig_handler_common(sig, mc);
+ sig_handler_common(sig, si, mc);
set_signals(enabled);
}
@@ -119,7 +156,7 @@ void set_sigstack(void *sig_stack, int s
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,
@@ -128,11 +165,11 @@ static void (*handlers[_NSIG])(int sig,
[SIGIO] = sig_handler,
[SIGWINCH] = sig_handler,
- [SIGVTALRM] = alarm_handler
+ [SIGVTALRM] = alarm_handler_ignore_siginfo
};
-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 +198,7 @@ static void hard_handler(int sig, siginf
while ((sig = ffs(pending)) != 0){
sig--;
pending &= ~(1 << sig);
- (*handlers[sig])(sig, mc);
+ (*handlers[sig])(sig, si, mc);
}
/*
@@ -273,9 +310,12 @@ 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);
diff -uprN -X linux-3.4.1/Documentation/dontdiff -x config.c -x config.tmp
linux-3.4.1/arch/um/os-Linux/skas/process.c
linux-3.4.1-mod/arch/um/os-Linux/skas/process.c
--- linux-3.4.1/arch/um/os-Linux/skas/process.c 2012-06-01 10:18:44.000000000
+0300
+++ linux-3.4.1-mod/arch/um/os-Linux/skas/process.c 2012-06-07
23:31:12.681859505 +0300
@@ -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;
if (getitimer(ITIMER_VIRTUAL, &timer))
printk(UM_KERN_ERR "Failed to get itimer, errno = %d\n", errno);
@@ -404,13 +405,17 @@ 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,
®s->faultinfo);
- (*sig_info[SIGSEGV])(SIGSEGV, regs);
+ (*sig_info[SIGSEGV])(SIGSEGV, &si,
+ regs);
}
else handle_segv(pid, regs);
break;
@@ -418,14 +423,14 @@ 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 +
@@ -439,7 +444,7 @@ 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:
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