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>
diff --git a/arch/um/include/shared/as-layout.h b/arch/um/include/shared/as-layout.h index 896e166..86daa54 100644 --- a/arch/um/include/shared/as-layout.h +++ b/arch/um/include/shared/as-layout.h
@@ -60,7 +60,8 @@ 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 --git a/arch/um/include/shared/irq_user.h b/arch/um/include/shared/irq_user.h index c6c784df..2b6d703 100644 --- a/arch/um/include/shared/irq_user.h +++ b/arch/um/include/shared/irq_user.h
@@ -20,7 +20,8 @@ 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);
diff --git a/arch/um/include/shared/kern_util.h b/arch/um/include/shared/kern_util.h index 00965d0..af6b6dc 100644 --- a/arch/um/include/shared/kern_util.h +++ b/arch/um/include/shared/kern_util.h
@@ -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 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 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 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));
diff --git a/arch/um/kernel/irq.c b/arch/um/kernel/irq.c index 00506c3..9883026 100644 --- a/arch/um/kernel/irq.c +++ b/arch/um/kernel/irq.c
@@ -30,7 +30,7 @@ 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;
diff --git a/arch/um/kernel/time.c b/arch/um/kernel/time.c index d1a23fb..5f76d4b 100644 --- a/arch/um/kernel/time.c +++ b/arch/um/kernel/time.c
@@ -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;
diff --git a/arch/um/kernel/trap.c b/arch/um/kernel/trap.c index 3be6076..0353b98 100644 --- a/arch/um/kernel/trap.c +++ b/arch/um/kernel/trap.c
@@ -172,7 +172,7 @@ 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 @@ 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 @@ 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); }
diff --git a/arch/um/os-Linux/internal.h b/arch/um/os-Linux/internal.h index 2c3c3ec..0dc2c9f 100644 --- a/arch/um/os-Linux/internal.h +++ b/arch/um/os-Linux/internal.h
@@ -1 +1 @@ -void alarm_handler(int, mcontext_t *); +void alarm_handler(int sig, struct siginfo *unused_si, mcontext_t *mc);
diff --git a/arch/um/os-Linux/signal.c b/arch/um/os-Linux/signal.c index 2d22f1f..6366ce9 100644 --- a/arch/um/os-Linux/signal.c +++ b/arch/um/os-Linux/signal.c
@@ -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 @@ [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 @@ 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 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 @@ block_signals(); - sig_handler_common(sig, mc); + sig_handler_common(sig, si, mc); set_signals(enabled); } @@ -85,10 +86,10 @@ get_regs_from_mc(®s, mc); regs.is_user = 0; unblock_signals(); - timer_handler(SIGVTALRM, ®s); + timer_handler(SIGVTALRM, NULL, ®s); } -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 @@ 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 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 @@ while ((sig = ffs(pending)) != 0){ sig--; pending &= ~(1 << sig); - (*handlers[sig])(sig, mc); + (*handlers[sig])(sig, si, mc); } /* @@ -273,9 +274,12 @@ * 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 --git a/arch/um/os-Linux/skas/process.c b/arch/um/os-Linux/skas/process.c index 2687f1f..d93bb40 100644 --- a/arch/um/os-Linux/skas/process.c +++ b/arch/um/os-Linux/skas/process.c
@@ -346,6 +346,7 @@ 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 @@ 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; @@ -421,14 +426,14 @@ 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 @@ case SIGFPE: case SIGWINCH: block_signals(); - (*sig_info[sig])(sig, regs); + (*sig_info[sig])(sig, &si, regs); unblock_signals(); break; default:
diff --git a/arch/um/os-Linux/time.c b/arch/um/os-Linux/time.c index 910499d..f602385 100644 --- a/arch/um/os-Linux/time.c +++ b/arch/um/os-Linux/time.c
@@ -87,7 +87,7 @@ static void deliver_alarm(void) { - alarm_handler(SIGVTALRM, NULL); + alarm_handler(SIGVTALRM, NULL, NULL); } static unsigned long long sleep_time(unsigned long long nsecs)