![Eric W. Biederman](/assets/img/avatar_default.png)
Stephen Rothwell <sfr@canb.auug.org.au> writes:
> Today's linux-next build of at least some av32 and arm configs failed like this:
>
> arch/avr32/kernel/signal.c:216: error: conflicting types for 'restart_syscall'
> include/linux/sched.h:2184: error: previous definition of 'restart_syscall' was here
>
> Caused by commit 690cc3ffe3
("syscall:
> Implement a convinience function restart_syscall") from the net tree.
Grrr. Some days it feels like all of the good names are already taken.
Let's just rename the two static users in arm and avr32 to get this
sorted out.
Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
326 lines
7.2 KiB
C
326 lines
7.2 KiB
C
/*
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* Copyright (C) 2004-2006 Atmel Corporation
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*
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* Based on linux/arch/sh/kernel/signal.c
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* Copyright (C) 1999, 2000 Niibe Yutaka & Kaz Kojima
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* Copyright (C) 1991, 1992 Linus Torvalds
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#include <linux/sched.h>
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#include <linux/mm.h>
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#include <linux/errno.h>
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#include <linux/ptrace.h>
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#include <linux/unistd.h>
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#include <linux/freezer.h>
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#include <asm/uaccess.h>
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#include <asm/ucontext.h>
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#include <asm/syscalls.h>
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#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
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asmlinkage int sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss,
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struct pt_regs *regs)
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{
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return do_sigaltstack(uss, uoss, regs->sp);
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}
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struct rt_sigframe
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{
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struct siginfo info;
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struct ucontext uc;
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unsigned long retcode;
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};
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static int
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restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
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{
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int err = 0;
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#define COPY(x) err |= __get_user(regs->x, &sc->x)
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COPY(sr);
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COPY(pc);
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COPY(lr);
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COPY(sp);
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COPY(r12);
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COPY(r11);
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COPY(r10);
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COPY(r9);
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COPY(r8);
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COPY(r7);
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COPY(r6);
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COPY(r5);
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COPY(r4);
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COPY(r3);
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COPY(r2);
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COPY(r1);
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COPY(r0);
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#undef COPY
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/*
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* Don't allow anyone to pretend they're running in supervisor
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* mode or something...
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*/
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err |= !valid_user_regs(regs);
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return err;
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}
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asmlinkage int sys_rt_sigreturn(struct pt_regs *regs)
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{
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struct rt_sigframe __user *frame;
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sigset_t set;
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frame = (struct rt_sigframe __user *)regs->sp;
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pr_debug("SIG return: frame = %p\n", frame);
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if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
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goto badframe;
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if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
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goto badframe;
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sigdelsetmask(&set, ~_BLOCKABLE);
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spin_lock_irq(¤t->sighand->siglock);
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current->blocked = set;
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recalc_sigpending();
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spin_unlock_irq(¤t->sighand->siglock);
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if (restore_sigcontext(regs, &frame->uc.uc_mcontext))
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goto badframe;
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if (do_sigaltstack(&frame->uc.uc_stack, NULL, regs->sp) == -EFAULT)
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goto badframe;
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pr_debug("Context restored: pc = %08lx, lr = %08lx, sp = %08lx\n",
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regs->pc, regs->lr, regs->sp);
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return regs->r12;
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badframe:
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force_sig(SIGSEGV, current);
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return 0;
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}
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static int
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setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs)
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{
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int err = 0;
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#define COPY(x) err |= __put_user(regs->x, &sc->x)
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COPY(sr);
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COPY(pc);
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COPY(lr);
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COPY(sp);
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COPY(r12);
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COPY(r11);
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COPY(r10);
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COPY(r9);
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COPY(r8);
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COPY(r7);
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COPY(r6);
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COPY(r5);
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COPY(r4);
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COPY(r3);
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COPY(r2);
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COPY(r1);
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COPY(r0);
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#undef COPY
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return err;
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}
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static inline void __user *
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get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, int framesize)
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{
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unsigned long sp = regs->sp;
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if ((ka->sa.sa_flags & SA_ONSTACK) && !sas_ss_flags(sp))
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sp = current->sas_ss_sp + current->sas_ss_size;
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return (void __user *)((sp - framesize) & ~3);
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}
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static int
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setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
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sigset_t *set, struct pt_regs *regs)
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{
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struct rt_sigframe __user *frame;
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int err = 0;
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frame = get_sigframe(ka, regs, sizeof(*frame));
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err = -EFAULT;
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if (!access_ok(VERIFY_WRITE, frame, sizeof (*frame)))
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goto out;
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/*
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* Set up the return code:
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*
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* mov r8, __NR_rt_sigreturn
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* scall
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*
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* Note: This will blow up since we're using a non-executable
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* stack. Better use SA_RESTORER.
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*/
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#if __NR_rt_sigreturn > 127
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# error __NR_rt_sigreturn must be < 127 to fit in a short mov
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#endif
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err = __put_user(0x3008d733 | (__NR_rt_sigreturn << 20),
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&frame->retcode);
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err |= copy_siginfo_to_user(&frame->info, info);
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/* Set up the ucontext */
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err |= __put_user(0, &frame->uc.uc_flags);
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err |= __put_user(NULL, &frame->uc.uc_link);
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err |= __put_user((void __user *)current->sas_ss_sp,
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&frame->uc.uc_stack.ss_sp);
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err |= __put_user(sas_ss_flags(regs->sp),
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&frame->uc.uc_stack.ss_flags);
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err |= __put_user(current->sas_ss_size,
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&frame->uc.uc_stack.ss_size);
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err |= setup_sigcontext(&frame->uc.uc_mcontext, regs);
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err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
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if (err)
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goto out;
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regs->r12 = sig;
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regs->r11 = (unsigned long) &frame->info;
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regs->r10 = (unsigned long) &frame->uc;
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regs->sp = (unsigned long) frame;
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if (ka->sa.sa_flags & SA_RESTORER)
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regs->lr = (unsigned long)ka->sa.sa_restorer;
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else {
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printk(KERN_NOTICE "[%s:%d] did not set SA_RESTORER\n",
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current->comm, current->pid);
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regs->lr = (unsigned long) &frame->retcode;
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}
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pr_debug("SIG deliver [%s:%d]: sig=%d sp=0x%lx pc=0x%lx->0x%p lr=0x%lx\n",
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current->comm, current->pid, sig, regs->sp,
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regs->pc, ka->sa.sa_handler, regs->lr);
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regs->pc = (unsigned long) ka->sa.sa_handler;
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out:
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return err;
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}
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static inline void setup_syscall_restart(struct pt_regs *regs)
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{
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if (regs->r12 == -ERESTART_RESTARTBLOCK)
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regs->r8 = __NR_restart_syscall;
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else
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regs->r12 = regs->r12_orig;
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regs->pc -= 2;
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}
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static inline void
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handle_signal(unsigned long sig, struct k_sigaction *ka, siginfo_t *info,
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sigset_t *oldset, struct pt_regs *regs, int syscall)
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{
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int ret;
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/*
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* Set up the stack frame
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*/
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ret = setup_rt_frame(sig, ka, info, oldset, regs);
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/*
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* Check that the resulting registers are sane
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*/
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ret |= !valid_user_regs(regs);
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/*
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* Block the signal if we were unsuccessful.
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*/
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if (ret != 0 || !(ka->sa.sa_flags & SA_NODEFER)) {
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spin_lock_irq(¤t->sighand->siglock);
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sigorsets(¤t->blocked, ¤t->blocked,
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&ka->sa.sa_mask);
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sigaddset(¤t->blocked, sig);
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recalc_sigpending();
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spin_unlock_irq(¤t->sighand->siglock);
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}
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if (ret == 0)
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return;
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force_sigsegv(sig, current);
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}
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/*
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* Note that 'init' is a special process: it doesn't get signals it
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* doesn't want to handle. Thus you cannot kill init even with a
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* SIGKILL even by mistake.
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*/
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int do_signal(struct pt_regs *regs, sigset_t *oldset, int syscall)
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{
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siginfo_t info;
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int signr;
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struct k_sigaction ka;
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/*
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* We want the common case to go fast, which is why we may in
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* certain cases get here from kernel mode. Just return
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* without doing anything if so.
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*/
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if (!user_mode(regs))
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return 0;
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if (test_thread_flag(TIF_RESTORE_SIGMASK))
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oldset = ¤t->saved_sigmask;
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else if (!oldset)
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oldset = ¤t->blocked;
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signr = get_signal_to_deliver(&info, &ka, regs, NULL);
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if (syscall) {
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switch (regs->r12) {
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case -ERESTART_RESTARTBLOCK:
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case -ERESTARTNOHAND:
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if (signr > 0) {
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regs->r12 = -EINTR;
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break;
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}
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/* fall through */
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case -ERESTARTSYS:
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if (signr > 0 && !(ka.sa.sa_flags & SA_RESTART)) {
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regs->r12 = -EINTR;
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break;
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}
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/* fall through */
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case -ERESTARTNOINTR:
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setup_syscall_restart(regs);
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}
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}
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if (signr == 0) {
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/* No signal to deliver -- put the saved sigmask back */
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if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
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clear_thread_flag(TIF_RESTORE_SIGMASK);
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sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL);
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}
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return 0;
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}
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handle_signal(signr, &ka, &info, oldset, regs, syscall);
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return 1;
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}
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asmlinkage void do_notify_resume(struct pt_regs *regs, struct thread_info *ti)
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{
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int syscall = 0;
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if ((sysreg_read(SR) & MODE_MASK) == MODE_SUPERVISOR)
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syscall = 1;
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if (ti->flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK))
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do_signal(regs, ¤t->blocked, syscall);
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}
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