diff options
Diffstat (limited to 'arch/sparc/kernel/signal_64.c')
| -rw-r--r-- | arch/sparc/kernel/signal_64.c | 595 |
1 files changed, 595 insertions, 0 deletions
diff --git a/arch/sparc/kernel/signal_64.c b/arch/sparc/kernel/signal_64.c new file mode 100644 index 000000000..570e43e6f --- /dev/null +++ b/arch/sparc/kernel/signal_64.c @@ -0,0 +1,595 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * arch/sparc64/kernel/signal.c + * + * Copyright (C) 1991, 1992 Linus Torvalds + * Copyright (C) 1995, 2008 David S. Miller (davem@davemloft.net) + * Copyright (C) 1996 Miguel de Icaza (miguel@nuclecu.unam.mx) + * Copyright (C) 1997 Eddie C. Dost (ecd@skynet.be) + * Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz) + */ + +#include <linux/sched.h> +#include <linux/kernel.h> +#include <linux/signal.h> +#include <linux/errno.h> +#include <linux/wait.h> +#include <linux/ptrace.h> +#include <linux/resume_user_mode.h> +#include <linux/unistd.h> +#include <linux/mm.h> +#include <linux/tty.h> +#include <linux/binfmts.h> +#include <linux/bitops.h> +#include <linux/context_tracking.h> + +#include <linux/uaccess.h> +#include <asm/ptrace.h> +#include <asm/fpumacro.h> +#include <asm/uctx.h> +#include <asm/siginfo.h> +#include <asm/visasm.h> +#include <asm/switch_to.h> +#include <asm/cacheflush.h> + +#include "sigutil.h" +#include "systbls.h" +#include "kernel.h" +#include "entry.h" + +/* {set, get}context() needed for 64-bit SparcLinux userland. */ +asmlinkage void sparc64_set_context(struct pt_regs *regs) +{ + struct ucontext __user *ucp = (struct ucontext __user *) + regs->u_regs[UREG_I0]; + enum ctx_state prev_state = exception_enter(); + mc_gregset_t __user *grp; + unsigned long pc, npc, tstate; + unsigned long fp, i7; + unsigned char fenab; + int err; + + synchronize_user_stack(); + if (get_thread_wsaved() || + (((unsigned long)ucp) & (sizeof(unsigned long)-1)) || + (!__access_ok(ucp, sizeof(*ucp)))) + goto do_sigsegv; + grp = &ucp->uc_mcontext.mc_gregs; + err = __get_user(pc, &((*grp)[MC_PC])); + err |= __get_user(npc, &((*grp)[MC_NPC])); + if (err || ((pc | npc) & 3)) + goto do_sigsegv; + if (regs->u_regs[UREG_I1]) { + sigset_t set; + + if (_NSIG_WORDS == 1) { + if (__get_user(set.sig[0], &ucp->uc_sigmask.sig[0])) + goto do_sigsegv; + } else { + if (__copy_from_user(&set, &ucp->uc_sigmask, sizeof(sigset_t))) + goto do_sigsegv; + } + set_current_blocked(&set); + } + if (test_thread_flag(TIF_32BIT)) { + pc &= 0xffffffff; + npc &= 0xffffffff; + } + regs->tpc = pc; + regs->tnpc = npc; + err |= __get_user(regs->y, &((*grp)[MC_Y])); + err |= __get_user(tstate, &((*grp)[MC_TSTATE])); + regs->tstate &= ~(TSTATE_ASI | TSTATE_ICC | TSTATE_XCC); + regs->tstate |= (tstate & (TSTATE_ASI | TSTATE_ICC | TSTATE_XCC)); + err |= __get_user(regs->u_regs[UREG_G1], (&(*grp)[MC_G1])); + err |= __get_user(regs->u_regs[UREG_G2], (&(*grp)[MC_G2])); + err |= __get_user(regs->u_regs[UREG_G3], (&(*grp)[MC_G3])); + err |= __get_user(regs->u_regs[UREG_G4], (&(*grp)[MC_G4])); + err |= __get_user(regs->u_regs[UREG_G5], (&(*grp)[MC_G5])); + err |= __get_user(regs->u_regs[UREG_G6], (&(*grp)[MC_G6])); + + /* Skip %g7 as that's the thread register in userspace. */ + + err |= __get_user(regs->u_regs[UREG_I0], (&(*grp)[MC_O0])); + err |= __get_user(regs->u_regs[UREG_I1], (&(*grp)[MC_O1])); + err |= __get_user(regs->u_regs[UREG_I2], (&(*grp)[MC_O2])); + err |= __get_user(regs->u_regs[UREG_I3], (&(*grp)[MC_O3])); + err |= __get_user(regs->u_regs[UREG_I4], (&(*grp)[MC_O4])); + err |= __get_user(regs->u_regs[UREG_I5], (&(*grp)[MC_O5])); + err |= __get_user(regs->u_regs[UREG_I6], (&(*grp)[MC_O6])); + err |= __get_user(regs->u_regs[UREG_I7], (&(*grp)[MC_O7])); + + err |= __get_user(fp, &(ucp->uc_mcontext.mc_fp)); + err |= __get_user(i7, &(ucp->uc_mcontext.mc_i7)); + err |= __put_user(fp, + (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[6]))); + err |= __put_user(i7, + (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[7]))); + + err |= __get_user(fenab, &(ucp->uc_mcontext.mc_fpregs.mcfpu_enab)); + if (fenab) { + unsigned long *fpregs = current_thread_info()->fpregs; + unsigned long fprs; + + fprs_write(0); + err |= __get_user(fprs, &(ucp->uc_mcontext.mc_fpregs.mcfpu_fprs)); + if (fprs & FPRS_DL) + err |= copy_from_user(fpregs, + &(ucp->uc_mcontext.mc_fpregs.mcfpu_fregs), + (sizeof(unsigned int) * 32)); + if (fprs & FPRS_DU) + err |= copy_from_user(fpregs+16, + ((unsigned long __user *)&(ucp->uc_mcontext.mc_fpregs.mcfpu_fregs))+16, + (sizeof(unsigned int) * 32)); + err |= __get_user(current_thread_info()->xfsr[0], + &(ucp->uc_mcontext.mc_fpregs.mcfpu_fsr)); + err |= __get_user(current_thread_info()->gsr[0], + &(ucp->uc_mcontext.mc_fpregs.mcfpu_gsr)); + regs->tstate &= ~TSTATE_PEF; + } + if (err) + goto do_sigsegv; +out: + exception_exit(prev_state); + return; +do_sigsegv: + force_sig(SIGSEGV); + goto out; +} + +asmlinkage void sparc64_get_context(struct pt_regs *regs) +{ + struct ucontext __user *ucp = (struct ucontext __user *) + regs->u_regs[UREG_I0]; + enum ctx_state prev_state = exception_enter(); + mc_gregset_t __user *grp; + mcontext_t __user *mcp; + unsigned long fp, i7; + unsigned char fenab; + int err; + + synchronize_user_stack(); + if (get_thread_wsaved() || clear_user(ucp, sizeof(*ucp))) + goto do_sigsegv; + +#if 1 + fenab = 0; /* IMO get_context is like any other system call, thus modifies FPU state -jj */ +#else + fenab = (current_thread_info()->fpsaved[0] & FPRS_FEF); +#endif + + mcp = &ucp->uc_mcontext; + grp = &mcp->mc_gregs; + + /* Skip over the trap instruction, first. */ + if (test_thread_flag(TIF_32BIT)) { + regs->tpc = (regs->tnpc & 0xffffffff); + regs->tnpc = (regs->tnpc + 4) & 0xffffffff; + } else { + regs->tpc = regs->tnpc; + regs->tnpc += 4; + } + err = 0; + if (_NSIG_WORDS == 1) + err |= __put_user(current->blocked.sig[0], + (unsigned long __user *)&ucp->uc_sigmask); + else + err |= __copy_to_user(&ucp->uc_sigmask, ¤t->blocked, + sizeof(sigset_t)); + + err |= __put_user(regs->tstate, &((*grp)[MC_TSTATE])); + err |= __put_user(regs->tpc, &((*grp)[MC_PC])); + err |= __put_user(regs->tnpc, &((*grp)[MC_NPC])); + err |= __put_user(regs->y, &((*grp)[MC_Y])); + err |= __put_user(regs->u_regs[UREG_G1], &((*grp)[MC_G1])); + err |= __put_user(regs->u_regs[UREG_G2], &((*grp)[MC_G2])); + err |= __put_user(regs->u_regs[UREG_G3], &((*grp)[MC_G3])); + err |= __put_user(regs->u_regs[UREG_G4], &((*grp)[MC_G4])); + err |= __put_user(regs->u_regs[UREG_G5], &((*grp)[MC_G5])); + err |= __put_user(regs->u_regs[UREG_G6], &((*grp)[MC_G6])); + err |= __put_user(regs->u_regs[UREG_G7], &((*grp)[MC_G7])); + err |= __put_user(regs->u_regs[UREG_I0], &((*grp)[MC_O0])); + err |= __put_user(regs->u_regs[UREG_I1], &((*grp)[MC_O1])); + err |= __put_user(regs->u_regs[UREG_I2], &((*grp)[MC_O2])); + err |= __put_user(regs->u_regs[UREG_I3], &((*grp)[MC_O3])); + err |= __put_user(regs->u_regs[UREG_I4], &((*grp)[MC_O4])); + err |= __put_user(regs->u_regs[UREG_I5], &((*grp)[MC_O5])); + err |= __put_user(regs->u_regs[UREG_I6], &((*grp)[MC_O6])); + err |= __put_user(regs->u_regs[UREG_I7], &((*grp)[MC_O7])); + + err |= __get_user(fp, + (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[6]))); + err |= __get_user(i7, + (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[7]))); + err |= __put_user(fp, &(mcp->mc_fp)); + err |= __put_user(i7, &(mcp->mc_i7)); + + err |= __put_user(fenab, &(mcp->mc_fpregs.mcfpu_enab)); + if (fenab) { + unsigned long *fpregs = current_thread_info()->fpregs; + unsigned long fprs; + + fprs = current_thread_info()->fpsaved[0]; + if (fprs & FPRS_DL) + err |= copy_to_user(&(mcp->mc_fpregs.mcfpu_fregs), fpregs, + (sizeof(unsigned int) * 32)); + if (fprs & FPRS_DU) + err |= copy_to_user( + ((unsigned long __user *)&(mcp->mc_fpregs.mcfpu_fregs))+16, fpregs+16, + (sizeof(unsigned int) * 32)); + err |= __put_user(current_thread_info()->xfsr[0], &(mcp->mc_fpregs.mcfpu_fsr)); + err |= __put_user(current_thread_info()->gsr[0], &(mcp->mc_fpregs.mcfpu_gsr)); + err |= __put_user(fprs, &(mcp->mc_fpregs.mcfpu_fprs)); + } + if (err) + goto do_sigsegv; +out: + exception_exit(prev_state); + return; +do_sigsegv: + force_sig(SIGSEGV); + goto out; +} + +/* Checks if the fp is valid. We always build rt signal frames which + * are 16-byte aligned, therefore we can always enforce that the + * restore frame has that property as well. + */ +static bool invalid_frame_pointer(void __user *fp) +{ + if (((unsigned long) fp) & 15) + return true; + return false; +} + +struct rt_signal_frame { + struct sparc_stackf ss; + siginfo_t info; + struct pt_regs regs; + __siginfo_fpu_t __user *fpu_save; + stack_t stack; + sigset_t mask; + __siginfo_rwin_t *rwin_save; +}; + +void do_rt_sigreturn(struct pt_regs *regs) +{ + unsigned long tpc, tnpc, tstate, ufp; + struct rt_signal_frame __user *sf; + __siginfo_fpu_t __user *fpu_save; + __siginfo_rwin_t __user *rwin_save; + sigset_t set; + int err; + + /* Always make any pending restarted system calls return -EINTR */ + current->restart_block.fn = do_no_restart_syscall; + + synchronize_user_stack (); + sf = (struct rt_signal_frame __user *) + (regs->u_regs [UREG_FP] + STACK_BIAS); + + /* 1. Make sure we are not getting garbage from the user */ + if (invalid_frame_pointer(sf)) + goto segv; + + if (get_user(ufp, &sf->regs.u_regs[UREG_FP])) + goto segv; + + if ((ufp + STACK_BIAS) & 0x7) + goto segv; + + err = __get_user(tpc, &sf->regs.tpc); + err |= __get_user(tnpc, &sf->regs.tnpc); + if (test_thread_flag(TIF_32BIT)) { + tpc &= 0xffffffff; + tnpc &= 0xffffffff; + } + err |= ((tpc | tnpc) & 3); + + /* 2. Restore the state */ + err |= __get_user(regs->y, &sf->regs.y); + err |= __get_user(tstate, &sf->regs.tstate); + err |= copy_from_user(regs->u_regs, sf->regs.u_regs, sizeof(regs->u_regs)); + + /* User can only change condition codes and %asi in %tstate. */ + regs->tstate &= ~(TSTATE_ASI | TSTATE_ICC | TSTATE_XCC); + regs->tstate |= (tstate & (TSTATE_ASI | TSTATE_ICC | TSTATE_XCC)); + + err |= __get_user(fpu_save, &sf->fpu_save); + if (!err && fpu_save) + err |= restore_fpu_state(regs, fpu_save); + + err |= __copy_from_user(&set, &sf->mask, sizeof(sigset_t)); + err |= restore_altstack(&sf->stack); + if (err) + goto segv; + + err |= __get_user(rwin_save, &sf->rwin_save); + if (!err && rwin_save) { + if (restore_rwin_state(rwin_save)) + goto segv; + } + + regs->tpc = tpc; + regs->tnpc = tnpc; + + /* Prevent syscall restart. */ + pt_regs_clear_syscall(regs); + + set_current_blocked(&set); + return; +segv: + force_sig(SIGSEGV); +} + +static inline void __user *get_sigframe(struct ksignal *ksig, struct pt_regs *regs, unsigned long framesize) +{ + unsigned long sp = regs->u_regs[UREG_FP] + STACK_BIAS; + + /* + * If we are on the alternate signal stack and would overflow it, don't. + * Return an always-bogus address instead so we will die with SIGSEGV. + */ + if (on_sig_stack(sp) && !likely(on_sig_stack(sp - framesize))) + return (void __user *) -1L; + + /* This is the X/Open sanctioned signal stack switching. */ + sp = sigsp(sp, ksig) - framesize; + + /* Always align the stack frame. This handles two cases. First, + * sigaltstack need not be mindful of platform specific stack + * alignment. Second, if we took this signal because the stack + * is not aligned properly, we'd like to take the signal cleanly + * and report that. + */ + sp &= ~15UL; + + return (void __user *) sp; +} + +static inline int +setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs) +{ + struct rt_signal_frame __user *sf; + int wsaved, err, sf_size; + void __user *tail; + + /* 1. Make sure everything is clean */ + synchronize_user_stack(); + save_and_clear_fpu(); + + wsaved = get_thread_wsaved(); + + sf_size = sizeof(struct rt_signal_frame); + if (current_thread_info()->fpsaved[0] & FPRS_FEF) + sf_size += sizeof(__siginfo_fpu_t); + if (wsaved) + sf_size += sizeof(__siginfo_rwin_t); + sf = (struct rt_signal_frame __user *) + get_sigframe(ksig, regs, sf_size); + + if (invalid_frame_pointer (sf)) { + if (show_unhandled_signals) + pr_info("%s[%d] bad frame in setup_rt_frame: %016lx TPC %016lx O7 %016lx\n", + current->comm, current->pid, (unsigned long)sf, + regs->tpc, regs->u_regs[UREG_I7]); + force_sigsegv(ksig->sig); + return -EINVAL; + } + + tail = (sf + 1); + + /* 2. Save the current process state */ + err = copy_to_user(&sf->regs, regs, sizeof (*regs)); + + if (current_thread_info()->fpsaved[0] & FPRS_FEF) { + __siginfo_fpu_t __user *fpu_save = tail; + tail += sizeof(__siginfo_fpu_t); + err |= save_fpu_state(regs, fpu_save); + err |= __put_user((u64)fpu_save, &sf->fpu_save); + } else { + err |= __put_user(0, &sf->fpu_save); + } + if (wsaved) { + __siginfo_rwin_t __user *rwin_save = tail; + tail += sizeof(__siginfo_rwin_t); + err |= save_rwin_state(wsaved, rwin_save); + err |= __put_user((u64)rwin_save, &sf->rwin_save); + set_thread_wsaved(0); + } else { + err |= __put_user(0, &sf->rwin_save); + } + + /* Setup sigaltstack */ + err |= __save_altstack(&sf->stack, regs->u_regs[UREG_FP]); + + err |= copy_to_user(&sf->mask, sigmask_to_save(), sizeof(sigset_t)); + + if (!wsaved) { + err |= raw_copy_in_user((u64 __user *)sf, + (u64 __user *)(regs->u_regs[UREG_FP] + + STACK_BIAS), + sizeof(struct reg_window)); + } else { + struct reg_window *rp; + + rp = ¤t_thread_info()->reg_window[wsaved - 1]; + err |= copy_to_user(sf, rp, sizeof(struct reg_window)); + } + if (ksig->ka.sa.sa_flags & SA_SIGINFO) + err |= copy_siginfo_to_user(&sf->info, &ksig->info); + else { + err |= __put_user(ksig->sig, &sf->info.si_signo); + err |= __put_user(SI_NOINFO, &sf->info.si_code); + } + if (err) + return err; + + /* 3. signal handler back-trampoline and parameters */ + regs->u_regs[UREG_FP] = ((unsigned long) sf) - STACK_BIAS; + regs->u_regs[UREG_I0] = ksig->sig; + regs->u_regs[UREG_I1] = (unsigned long) &sf->info; + + /* The sigcontext is passed in this way because of how it + * is defined in GLIBC's /usr/include/bits/sigcontext.h + * for sparc64. It includes the 128 bytes of siginfo_t. + */ + regs->u_regs[UREG_I2] = (unsigned long) &sf->info; + + /* 5. signal handler */ + regs->tpc = (unsigned long) ksig->ka.sa.sa_handler; + regs->tnpc = (regs->tpc + 4); + if (test_thread_flag(TIF_32BIT)) { + regs->tpc &= 0xffffffff; + regs->tnpc &= 0xffffffff; + } + /* 4. return to kernel instructions */ + regs->u_regs[UREG_I7] = (unsigned long)ksig->ka.ka_restorer; + return 0; +} + +static inline void syscall_restart(unsigned long orig_i0, struct pt_regs *regs, + struct sigaction *sa) +{ + switch (regs->u_regs[UREG_I0]) { + case ERESTART_RESTARTBLOCK: + case ERESTARTNOHAND: + no_system_call_restart: + regs->u_regs[UREG_I0] = EINTR; + regs->tstate |= (TSTATE_ICARRY|TSTATE_XCARRY); + break; + case ERESTARTSYS: + if (!(sa->sa_flags & SA_RESTART)) + goto no_system_call_restart; + fallthrough; + case ERESTARTNOINTR: + regs->u_regs[UREG_I0] = orig_i0; + regs->tpc -= 4; + regs->tnpc -= 4; + } +} + +/* Note that 'init' is a special process: it doesn't get signals it doesn't + * want to handle. Thus you cannot kill init even with a SIGKILL even by + * mistake. + */ +static void do_signal(struct pt_regs *regs, unsigned long orig_i0) +{ + struct ksignal ksig; + int restart_syscall; + bool has_handler; + + /* It's a lot of work and synchronization to add a new ptrace + * register for GDB to save and restore in order to get + * orig_i0 correct for syscall restarts when debugging. + * + * Although it should be the case that most of the global + * registers are volatile across a system call, glibc already + * depends upon that fact that we preserve them. So we can't + * just use any global register to save away the orig_i0 value. + * + * In particular %g2, %g3, %g4, and %g5 are all assumed to be + * preserved across a system call trap by various pieces of + * code in glibc. + * + * %g7 is used as the "thread register". %g6 is not used in + * any fixed manner. %g6 is used as a scratch register and + * a compiler temporary, but it's value is never used across + * a system call. Therefore %g6 is usable for orig_i0 storage. + */ + if (pt_regs_is_syscall(regs) && + (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY))) + regs->u_regs[UREG_G6] = orig_i0; + +#ifdef CONFIG_COMPAT + if (test_thread_flag(TIF_32BIT)) { + do_signal32(regs); + return; + } +#endif + + has_handler = get_signal(&ksig); + + restart_syscall = 0; + if (pt_regs_is_syscall(regs) && + (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY))) { + restart_syscall = 1; + orig_i0 = regs->u_regs[UREG_G6]; + } + + if (has_handler) { + if (restart_syscall) + syscall_restart(orig_i0, regs, &ksig.ka.sa); + signal_setup_done(setup_rt_frame(&ksig, regs), &ksig, 0); + } else { + if (restart_syscall) { + switch (regs->u_regs[UREG_I0]) { + case ERESTARTNOHAND: + case ERESTARTSYS: + case ERESTARTNOINTR: + /* replay the system call when we are done */ + regs->u_regs[UREG_I0] = orig_i0; + regs->tpc -= 4; + regs->tnpc -= 4; + pt_regs_clear_syscall(regs); + fallthrough; + case ERESTART_RESTARTBLOCK: + regs->u_regs[UREG_G1] = __NR_restart_syscall; + regs->tpc -= 4; + regs->tnpc -= 4; + pt_regs_clear_syscall(regs); + } + } + restore_saved_sigmask(); + } +} + +void do_notify_resume(struct pt_regs *regs, unsigned long orig_i0, unsigned long thread_info_flags) +{ + user_exit(); + if (thread_info_flags & _TIF_UPROBE) + uprobe_notify_resume(regs); + if (thread_info_flags & (_TIF_SIGPENDING | _TIF_NOTIFY_SIGNAL)) + do_signal(regs, orig_i0); + if (thread_info_flags & _TIF_NOTIFY_RESUME) + resume_user_mode_work(regs); + user_enter(); +} + +/* + * Compile-time assertions for siginfo_t offsets. Check NSIG* as well, as + * changes likely come with new fields that should be added below. + */ +static_assert(NSIGILL == 11); +static_assert(NSIGFPE == 15); +static_assert(NSIGSEGV == 9); +static_assert(NSIGBUS == 5); +static_assert(NSIGTRAP == 6); +static_assert(NSIGCHLD == 6); +static_assert(NSIGSYS == 2); +static_assert(sizeof(siginfo_t) == 128); +static_assert(__alignof__(siginfo_t) == 8); +static_assert(offsetof(siginfo_t, si_signo) == 0x00); +static_assert(offsetof(siginfo_t, si_errno) == 0x04); +static_assert(offsetof(siginfo_t, si_code) == 0x08); +static_assert(offsetof(siginfo_t, si_pid) == 0x10); +static_assert(offsetof(siginfo_t, si_uid) == 0x14); +static_assert(offsetof(siginfo_t, si_tid) == 0x10); +static_assert(offsetof(siginfo_t, si_overrun) == 0x14); +static_assert(offsetof(siginfo_t, si_status) == 0x18); +static_assert(offsetof(siginfo_t, si_utime) == 0x20); +static_assert(offsetof(siginfo_t, si_stime) == 0x28); +static_assert(offsetof(siginfo_t, si_value) == 0x18); +static_assert(offsetof(siginfo_t, si_int) == 0x18); +static_assert(offsetof(siginfo_t, si_ptr) == 0x18); +static_assert(offsetof(siginfo_t, si_addr) == 0x10); +static_assert(offsetof(siginfo_t, si_trapno) == 0x18); +static_assert(offsetof(siginfo_t, si_addr_lsb) == 0x18); +static_assert(offsetof(siginfo_t, si_lower) == 0x20); +static_assert(offsetof(siginfo_t, si_upper) == 0x28); +static_assert(offsetof(siginfo_t, si_pkey) == 0x20); +static_assert(offsetof(siginfo_t, si_perf_data) == 0x18); +static_assert(offsetof(siginfo_t, si_perf_type) == 0x20); +static_assert(offsetof(siginfo_t, si_perf_flags) == 0x24); +static_assert(offsetof(siginfo_t, si_band) == 0x10); +static_assert(offsetof(siginfo_t, si_fd) == 0x14); |