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-rw-r--r--arch/um/sys-i386/signal.c382
1 files changed, 382 insertions, 0 deletions
diff --git a/arch/um/sys-i386/signal.c b/arch/um/sys-i386/signal.c
new file mode 100644
index 00000000000..76ba87254b2
--- /dev/null
+++ b/arch/um/sys-i386/signal.c
@@ -0,0 +1,382 @@
+/*
+ * Copyright (C) 2004 Jeff Dike (jdike@addtoit.com)
+ * Licensed under the GPL
+ */
+
+#include "linux/signal.h"
+#include "linux/ptrace.h"
+#include "asm/current.h"
+#include "asm/ucontext.h"
+#include "asm/uaccess.h"
+#include "asm/unistd.h"
+#include "frame_kern.h"
+#include "signal_user.h"
+#include "sigcontext.h"
+#include "registers.h"
+#include "mode.h"
+
+#ifdef CONFIG_MODE_SKAS
+
+#include "skas.h"
+
+static int copy_sc_from_user_skas(struct pt_regs *regs,
+ struct sigcontext *from)
+{
+ struct sigcontext sc;
+ unsigned long fpregs[HOST_FP_SIZE];
+ int err;
+
+ err = copy_from_user(&sc, from, sizeof(sc));
+ err |= copy_from_user(fpregs, sc.fpstate, sizeof(fpregs));
+ if(err)
+ return(err);
+
+ REGS_GS(regs->regs.skas.regs) = sc.gs;
+ REGS_FS(regs->regs.skas.regs) = sc.fs;
+ REGS_ES(regs->regs.skas.regs) = sc.es;
+ REGS_DS(regs->regs.skas.regs) = sc.ds;
+ REGS_EDI(regs->regs.skas.regs) = sc.edi;
+ REGS_ESI(regs->regs.skas.regs) = sc.esi;
+ REGS_EBP(regs->regs.skas.regs) = sc.ebp;
+ REGS_SP(regs->regs.skas.regs) = sc.esp;
+ REGS_EBX(regs->regs.skas.regs) = sc.ebx;
+ REGS_EDX(regs->regs.skas.regs) = sc.edx;
+ REGS_ECX(regs->regs.skas.regs) = sc.ecx;
+ REGS_EAX(regs->regs.skas.regs) = sc.eax;
+ REGS_IP(regs->regs.skas.regs) = sc.eip;
+ REGS_CS(regs->regs.skas.regs) = sc.cs;
+ REGS_EFLAGS(regs->regs.skas.regs) = sc.eflags;
+ REGS_SS(regs->regs.skas.regs) = sc.ss;
+ regs->regs.skas.fault_addr = sc.cr2;
+ regs->regs.skas.fault_type = FAULT_WRITE(sc.err);
+ regs->regs.skas.trap_type = sc.trapno;
+
+ err = restore_fp_registers(userspace_pid[0], fpregs);
+ if(err < 0){
+ printk("copy_sc_from_user_skas - PTRACE_SETFPREGS failed, "
+ "errno = %d\n", err);
+ return(1);
+ }
+
+ return(0);
+}
+
+int copy_sc_to_user_skas(struct sigcontext *to, struct _fpstate *to_fp,
+ struct pt_regs *regs, unsigned long fault_addr,
+ int fault_type)
+{
+ struct sigcontext sc;
+ unsigned long fpregs[HOST_FP_SIZE];
+ int err;
+
+ sc.gs = REGS_GS(regs->regs.skas.regs);
+ sc.fs = REGS_FS(regs->regs.skas.regs);
+ sc.es = REGS_ES(regs->regs.skas.regs);
+ sc.ds = REGS_DS(regs->regs.skas.regs);
+ sc.edi = REGS_EDI(regs->regs.skas.regs);
+ sc.esi = REGS_ESI(regs->regs.skas.regs);
+ sc.ebp = REGS_EBP(regs->regs.skas.regs);
+ sc.esp = REGS_SP(regs->regs.skas.regs);
+ sc.ebx = REGS_EBX(regs->regs.skas.regs);
+ sc.edx = REGS_EDX(regs->regs.skas.regs);
+ sc.ecx = REGS_ECX(regs->regs.skas.regs);
+ sc.eax = REGS_EAX(regs->regs.skas.regs);
+ sc.eip = REGS_IP(regs->regs.skas.regs);
+ sc.cs = REGS_CS(regs->regs.skas.regs);
+ sc.eflags = REGS_EFLAGS(regs->regs.skas.regs);
+ sc.esp_at_signal = regs->regs.skas.regs[UESP];
+ sc.ss = regs->regs.skas.regs[SS];
+ sc.cr2 = fault_addr;
+ sc.err = TO_SC_ERR(fault_type);
+ sc.trapno = regs->regs.skas.trap_type;
+
+ err = save_fp_registers(userspace_pid[0], fpregs);
+ if(err < 0){
+ printk("copy_sc_to_user_skas - PTRACE_GETFPREGS failed, "
+ "errno = %d\n", err);
+ return(1);
+ }
+ to_fp = (to_fp ? to_fp : (struct _fpstate *) (to + 1));
+ sc.fpstate = to_fp;
+
+ if(err)
+ return(err);
+
+ return(copy_to_user(to, &sc, sizeof(sc)) ||
+ copy_to_user(to_fp, fpregs, sizeof(fpregs)));
+}
+#endif
+
+#ifdef CONFIG_MODE_TT
+
+/* These copy a sigcontext to/from userspace. They copy the fpstate pointer,
+ * blowing away the old, good one. So, that value is saved, and then restored
+ * after the sigcontext copy. In copy_from, the variable holding the saved
+ * fpstate pointer, and the sigcontext that it should be restored to are both
+ * in the kernel, so we can just restore using an assignment. In copy_to, the
+ * saved pointer is in the kernel, but the sigcontext is in userspace, so we
+ * copy_to_user it.
+ */
+int copy_sc_from_user_tt(struct sigcontext *to, struct sigcontext *from,
+ int fpsize)
+{
+ struct _fpstate *to_fp, *from_fp;
+ unsigned long sigs;
+ int err;
+
+ to_fp = to->fpstate;
+ from_fp = from->fpstate;
+ sigs = to->oldmask;
+ err = copy_from_user(to, from, sizeof(*to));
+ to->oldmask = sigs;
+ to->fpstate = to_fp;
+ if(to_fp != NULL)
+ err |= copy_from_user(to_fp, from_fp, fpsize);
+ return(err);
+}
+
+int copy_sc_to_user_tt(struct sigcontext *to, struct _fpstate *fp,
+ struct sigcontext *from, int fpsize)
+{
+ struct _fpstate *to_fp, *from_fp;
+ int err;
+
+ to_fp = (fp ? fp : (struct _fpstate *) (to + 1));
+ from_fp = from->fpstate;
+ err = copy_to_user(to, from, sizeof(*to));
+ if(from_fp != NULL){
+ err |= copy_to_user(&to->fpstate, &to_fp, sizeof(to->fpstate));
+ err |= copy_to_user(to_fp, from_fp, fpsize);
+ }
+ return(err);
+}
+#endif
+
+static int copy_sc_from_user(struct pt_regs *to, void __user *from)
+{
+ int ret;
+
+ ret = CHOOSE_MODE(copy_sc_from_user_tt(UPT_SC(&to->regs), from,
+ sizeof(struct _fpstate)),
+ copy_sc_from_user_skas(to, from));
+ return(ret);
+}
+
+static int copy_sc_to_user(struct sigcontext *to, struct _fpstate *fp,
+ struct pt_regs *from)
+{
+ return(CHOOSE_MODE(copy_sc_to_user_tt(to, fp, UPT_SC(&from->regs),
+ sizeof(*fp)),
+ copy_sc_to_user_skas(to, fp, from,
+ current->thread.cr2,
+ current->thread.err)));
+}
+
+static int copy_ucontext_to_user(struct ucontext *uc, struct _fpstate *fp,
+ sigset_t *set, unsigned long sp)
+{
+ int err = 0;
+
+ err |= put_user(current->sas_ss_sp, &uc->uc_stack.ss_sp);
+ err |= put_user(sas_ss_flags(sp), &uc->uc_stack.ss_flags);
+ err |= put_user(current->sas_ss_size, &uc->uc_stack.ss_size);
+ err |= copy_sc_to_user(&uc->uc_mcontext, fp, &current->thread.regs);
+ err |= copy_to_user(&uc->uc_sigmask, set, sizeof(*set));
+ return(err);
+}
+
+struct sigframe
+{
+ char *pretcode;
+ int sig;
+ struct sigcontext sc;
+ struct _fpstate fpstate;
+ unsigned long extramask[_NSIG_WORDS-1];
+ char retcode[8];
+};
+
+struct rt_sigframe
+{
+ char *pretcode;
+ int sig;
+ struct siginfo *pinfo;
+ void *puc;
+ struct siginfo info;
+ struct ucontext uc;
+ struct _fpstate fpstate;
+ char retcode[8];
+};
+
+int setup_signal_stack_sc(unsigned long stack_top, int sig,
+ struct k_sigaction *ka, struct pt_regs *regs,
+ sigset_t *mask)
+{
+ struct sigframe __user *frame;
+ void *restorer;
+ int err = 0;
+
+ stack_top &= -8UL;
+ frame = (struct sigframe *) stack_top - 1;
+ if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
+ return 1;
+
+ restorer = (void *) frame->retcode;
+ if(ka->sa.sa_flags & SA_RESTORER)
+ restorer = ka->sa.sa_restorer;
+
+ err |= __put_user(restorer, &frame->pretcode);
+ err |= __put_user(sig, &frame->sig);
+ err |= copy_sc_to_user(&frame->sc, NULL, regs);
+ err |= __put_user(mask->sig[0], &frame->sc.oldmask);
+ if (_NSIG_WORDS > 1)
+ err |= __copy_to_user(&frame->extramask, &mask->sig[1],
+ sizeof(frame->extramask));
+
+ /*
+ * This is popl %eax ; movl $,%eax ; int $0x80
+ *
+ * WE DO NOT USE IT ANY MORE! It's only left here for historical
+ * reasons and because gdb uses it as a signature to notice
+ * signal handler stack frames.
+ */
+ err |= __put_user(0xb858, (short __user *)(frame->retcode+0));
+ err |= __put_user(__NR_sigreturn, (int __user *)(frame->retcode+2));
+ err |= __put_user(0x80cd, (short __user *)(frame->retcode+6));
+
+ if(err)
+ return(err);
+
+ PT_REGS_SP(regs) = (unsigned long) frame;
+ PT_REGS_IP(regs) = (unsigned long) ka->sa.sa_handler;
+ PT_REGS_EAX(regs) = (unsigned long) sig;
+ PT_REGS_EDX(regs) = (unsigned long) 0;
+ PT_REGS_ECX(regs) = (unsigned long) 0;
+
+ if ((current->ptrace & PT_DTRACE) && (current->ptrace & PT_PTRACED))
+ ptrace_notify(SIGTRAP);
+ return(0);
+}
+
+int setup_signal_stack_si(unsigned long stack_top, int sig,
+ struct k_sigaction *ka, struct pt_regs *regs,
+ siginfo_t *info, sigset_t *mask)
+{
+ struct rt_sigframe __user *frame;
+ void *restorer;
+ int err = 0;
+
+ stack_top &= -8UL;
+ frame = (struct rt_sigframe *) stack_top - 1;
+ if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
+ return 1;
+
+ restorer = (void *) frame->retcode;
+ if(ka->sa.sa_flags & SA_RESTORER)
+ restorer = ka->sa.sa_restorer;
+
+ err |= __put_user(restorer, &frame->pretcode);
+ err |= __put_user(sig, &frame->sig);
+ err |= __put_user(&frame->info, &frame->pinfo);
+ err |= __put_user(&frame->uc, &frame->puc);
+ err |= copy_siginfo_to_user(&frame->info, info);
+ err |= copy_ucontext_to_user(&frame->uc, &frame->fpstate, mask,
+ PT_REGS_SP(regs));
+
+ /*
+ * This is movl $,%eax ; int $0x80
+ *
+ * WE DO NOT USE IT ANY MORE! It's only left here for historical
+ * reasons and because gdb uses it as a signature to notice
+ * signal handler stack frames.
+ */
+ err |= __put_user(0xb8, (char __user *)(frame->retcode+0));
+ err |= __put_user(__NR_rt_sigreturn, (int __user *)(frame->retcode+1));
+ err |= __put_user(0x80cd, (short __user *)(frame->retcode+5));
+
+ if(err)
+ return(err);
+
+ PT_REGS_SP(regs) = (unsigned long) frame;
+ PT_REGS_IP(regs) = (unsigned long) ka->sa.sa_handler;
+ PT_REGS_EAX(regs) = (unsigned long) sig;
+ PT_REGS_EDX(regs) = (unsigned long) &frame->info;
+ PT_REGS_ECX(regs) = (unsigned long) &frame->uc;
+
+ if ((current->ptrace & PT_DTRACE) && (current->ptrace & PT_PTRACED))
+ ptrace_notify(SIGTRAP);
+ return(0);
+}
+
+long sys_sigreturn(struct pt_regs regs)
+{
+ unsigned long sp = PT_REGS_SP(&current->thread.regs);
+ struct sigframe __user *frame = (struct sigframe *)(sp - 8);
+ sigset_t set;
+ struct sigcontext __user *sc = &frame->sc;
+ unsigned long __user *oldmask = &sc->oldmask;
+ unsigned long __user *extramask = frame->extramask;
+ int sig_size = (_NSIG_WORDS - 1) * sizeof(unsigned long);
+
+ if(copy_from_user(&set.sig[0], oldmask, sizeof(&set.sig[0])) ||
+ copy_from_user(&set.sig[1], extramask, sig_size))
+ goto segfault;
+
+ sigdelsetmask(&set, ~_BLOCKABLE);
+
+ spin_lock_irq(&current->sighand->siglock);
+ current->blocked = set;
+ recalc_sigpending();
+ spin_unlock_irq(&current->sighand->siglock);
+
+ if(copy_sc_from_user(&current->thread.regs, sc))
+ goto segfault;
+
+ /* Avoid ERESTART handling */
+ PT_REGS_SYSCALL_NR(&current->thread.regs) = -1;
+ return(PT_REGS_SYSCALL_RET(&current->thread.regs));
+
+ segfault:
+ force_sig(SIGSEGV, current);
+ return 0;
+}
+
+long sys_rt_sigreturn(struct pt_regs regs)
+{
+ unsigned long __user sp = PT_REGS_SP(&current->thread.regs);
+ struct rt_sigframe __user *frame = (struct rt_sigframe *) (sp - 4);
+ sigset_t set;
+ struct ucontext __user *uc = &frame->uc;
+ int sig_size = _NSIG_WORDS * sizeof(unsigned long);
+
+ if(copy_from_user(&set, &uc->uc_sigmask, sig_size))
+ goto segfault;
+
+ sigdelsetmask(&set, ~_BLOCKABLE);
+
+ spin_lock_irq(&current->sighand->siglock);
+ current->blocked = set;
+ recalc_sigpending();
+ spin_unlock_irq(&current->sighand->siglock);
+
+ if(copy_sc_from_user(&current->thread.regs, &uc->uc_mcontext))
+ goto segfault;
+
+ /* Avoid ERESTART handling */
+ PT_REGS_SYSCALL_NR(&current->thread.regs) = -1;
+ return(PT_REGS_SYSCALL_RET(&current->thread.regs));
+
+ segfault:
+ force_sig(SIGSEGV, current);
+ return 0;
+}
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only. This must remain at the end
+ * of the file.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-file-style: "linux"
+ * End:
+ */