diff options
Diffstat (limited to 'sys/amd64/linux32/linux32_sysvec.c')
| -rw-r--r-- | sys/amd64/linux32/linux32_sysvec.c | 1088 |
1 files changed, 1088 insertions, 0 deletions
diff --git a/sys/amd64/linux32/linux32_sysvec.c b/sys/amd64/linux32/linux32_sysvec.c new file mode 100644 index 0000000..aec316c --- /dev/null +++ b/sys/amd64/linux32/linux32_sysvec.c @@ -0,0 +1,1088 @@ +/*- + * Copyright (c) 2004 Tim J. Robbins + * Copyright (c) 2003 Peter Wemm + * Copyright (c) 2002 Doug Rabson + * Copyright (c) 1998-1999 Andrew Gallatin + * Copyright (c) 1994-1996 Søren Schmidt + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer + * in this position and unchanged. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +/* XXX we use functions that might not exist. */ +#include "opt_compat.h" +#include "opt_ia32.h" + +#ifndef COMPAT_43 +#error "Unable to compile Linux-emulator due to missing COMPAT_43 option!" +#endif +#ifndef IA32 +#error "Unable to compile Linux-emulator due to missing IA32 option!" +#endif + +#define __ELF_WORD_SIZE 32 + +#include <sys/param.h> +#include <sys/systm.h> +#include <sys/exec.h> +#include <sys/imgact.h> +#include <sys/imgact_elf.h> +#include <sys/kernel.h> +#include <sys/lock.h> +#include <sys/malloc.h> +#include <sys/module.h> +#include <sys/mutex.h> +#include <sys/proc.h> +#include <sys/signalvar.h> +#include <sys/sysctl.h> +#include <sys/syscallsubr.h> +#include <sys/sysent.h> +#include <sys/sysproto.h> +#include <sys/user.h> +#include <sys/vnode.h> + +#include <vm/vm.h> +#include <vm/pmap.h> +#include <vm/vm_extern.h> +#include <vm/vm_map.h> +#include <vm/vm_object.h> +#include <vm/vm_page.h> +#include <vm/vm_param.h> + +#include <machine/cpu.h> +#include <machine/md_var.h> +#include <machine/specialreg.h> + +#include <amd64/linux32/linux.h> +#include <amd64/linux32/linux32_proto.h> +#include <compat/linux/linux_mib.h> +#include <compat/linux/linux_signal.h> +#include <compat/linux/linux_util.h> + +MODULE_VERSION(linux, 1); +MODULE_DEPEND(linux, sysvmsg, 1, 1, 1); +MODULE_DEPEND(linux, sysvsem, 1, 1, 1); +MODULE_DEPEND(linux, sysvshm, 1, 1, 1); + +MALLOC_DEFINE(M_LINUX, "linux", "Linux mode structures"); + +#define AUXARGS_ENTRY_32(pos, id, val) \ + do { \ + suword32(pos++, id); \ + suword32(pos++, val); \ + } while (0) + +#if BYTE_ORDER == LITTLE_ENDIAN +#define SHELLMAGIC 0x2123 /* #! */ +#else +#define SHELLMAGIC 0x2321 +#endif + +/* + * Allow the sendsig functions to use the ldebug() facility + * even though they are not syscalls themselves. Map them + * to syscall 0. This is slightly less bogus than using + * ldebug(sigreturn). + */ +#define LINUX_SYS_linux_rt_sendsig 0 +#define LINUX_SYS_linux_sendsig 0 + +extern char linux_sigcode[]; +extern int linux_szsigcode; + +extern struct sysent linux_sysent[LINUX_SYS_MAXSYSCALL]; + +SET_DECLARE(linux_ioctl_handler_set, struct linux_ioctl_handler); + +static int elf_linux_fixup(register_t **stack_base, + struct image_params *iparams); +static register_t *linux_copyout_strings(struct image_params *imgp); +static void linux_prepsyscall(struct trapframe *tf, int *args, u_int *code, + caddr_t *params); +static void linux_sendsig(sig_t catcher, int sig, sigset_t *mask, + u_long code); +static void exec_linux_setregs(struct thread *td, u_long entry, + u_long stack, u_long ps_strings); +static void linux32_fixlimits(struct image_params *imgp); + +/* + * Linux syscalls return negative errno's, we do positive and map them + */ +static int bsd_to_linux_errno[ELAST + 1] = { + -0, -1, -2, -3, -4, -5, -6, -7, -8, -9, + -10, -35, -12, -13, -14, -15, -16, -17, -18, -19, + -20, -21, -22, -23, -24, -25, -26, -27, -28, -29, + -30, -31, -32, -33, -34, -11,-115,-114, -88, -89, + -90, -91, -92, -93, -94, -95, -96, -97, -98, -99, + -100,-101,-102,-103,-104,-105,-106,-107,-108,-109, + -110,-111, -40, -36,-112,-113, -39, -11, -87,-122, + -116, -66, -6, -6, -6, -6, -6, -37, -38, -9, + -6, -6, -43, -42, -75, -6, -84 +}; + +int bsd_to_linux_signal[LINUX_SIGTBLSZ] = { + LINUX_SIGHUP, LINUX_SIGINT, LINUX_SIGQUIT, LINUX_SIGILL, + LINUX_SIGTRAP, LINUX_SIGABRT, 0, LINUX_SIGFPE, + LINUX_SIGKILL, LINUX_SIGBUS, LINUX_SIGSEGV, LINUX_SIGSYS, + LINUX_SIGPIPE, LINUX_SIGALRM, LINUX_SIGTERM, LINUX_SIGURG, + LINUX_SIGSTOP, LINUX_SIGTSTP, LINUX_SIGCONT, LINUX_SIGCHLD, + LINUX_SIGTTIN, LINUX_SIGTTOU, LINUX_SIGIO, LINUX_SIGXCPU, + LINUX_SIGXFSZ, LINUX_SIGVTALRM, LINUX_SIGPROF, LINUX_SIGWINCH, + 0, LINUX_SIGUSR1, LINUX_SIGUSR2 +}; + +int linux_to_bsd_signal[LINUX_SIGTBLSZ] = { + SIGHUP, SIGINT, SIGQUIT, SIGILL, + SIGTRAP, SIGABRT, SIGBUS, SIGFPE, + SIGKILL, SIGUSR1, SIGSEGV, SIGUSR2, + SIGPIPE, SIGALRM, SIGTERM, SIGBUS, + SIGCHLD, SIGCONT, SIGSTOP, SIGTSTP, + SIGTTIN, SIGTTOU, SIGURG, SIGXCPU, + SIGXFSZ, SIGVTALRM, SIGPROF, SIGWINCH, + SIGIO, SIGURG, SIGSYS +}; + +#define LINUX_T_UNKNOWN 255 +static int _bsd_to_linux_trapcode[] = { + LINUX_T_UNKNOWN, /* 0 */ + 6, /* 1 T_PRIVINFLT */ + LINUX_T_UNKNOWN, /* 2 */ + 3, /* 3 T_BPTFLT */ + LINUX_T_UNKNOWN, /* 4 */ + LINUX_T_UNKNOWN, /* 5 */ + 16, /* 6 T_ARITHTRAP */ + 254, /* 7 T_ASTFLT */ + LINUX_T_UNKNOWN, /* 8 */ + 13, /* 9 T_PROTFLT */ + 1, /* 10 T_TRCTRAP */ + LINUX_T_UNKNOWN, /* 11 */ + 14, /* 12 T_PAGEFLT */ + LINUX_T_UNKNOWN, /* 13 */ + 17, /* 14 T_ALIGNFLT */ + LINUX_T_UNKNOWN, /* 15 */ + LINUX_T_UNKNOWN, /* 16 */ + LINUX_T_UNKNOWN, /* 17 */ + 0, /* 18 T_DIVIDE */ + 2, /* 19 T_NMI */ + 4, /* 20 T_OFLOW */ + 5, /* 21 T_BOUND */ + 7, /* 22 T_DNA */ + 8, /* 23 T_DOUBLEFLT */ + 9, /* 24 T_FPOPFLT */ + 10, /* 25 T_TSSFLT */ + 11, /* 26 T_SEGNPFLT */ + 12, /* 27 T_STKFLT */ + 18, /* 28 T_MCHK */ + 19, /* 29 T_XMMFLT */ + 15 /* 30 T_RESERVED */ +}; +#define bsd_to_linux_trapcode(code) \ + ((code)<sizeof(_bsd_to_linux_trapcode)/sizeof(*_bsd_to_linux_trapcode)? \ + _bsd_to_linux_trapcode[(code)]: \ + LINUX_T_UNKNOWN) + +struct linux32_ps_strings { + u_int32_t ps_argvstr; /* first of 0 or more argument strings */ + int ps_nargvstr; /* the number of argument strings */ + u_int32_t ps_envstr; /* first of 0 or more environment strings */ + int ps_nenvstr; /* the number of environment strings */ +}; + +/* + * If FreeBSD & Linux have a difference of opinion about what a trap + * means, deal with it here. + * + * MPSAFE + */ +static int +translate_traps(int signal, int trap_code) +{ + if (signal != SIGBUS) + return signal; + switch (trap_code) { + case T_PROTFLT: + case T_TSSFLT: + case T_DOUBLEFLT: + case T_PAGEFLT: + return SIGSEGV; + default: + return signal; + } +} + +static int +elf_linux_fixup(register_t **stack_base, struct image_params *imgp) +{ + Elf32_Auxargs *args; + Elf32_Addr *base; + Elf32_Addr *pos; + + KASSERT(curthread->td_proc == imgp->proc && + (curthread->td_proc->p_flag & P_SA) == 0, + ("unsafe elf_linux_fixup(), should be curproc")); + base = (Elf32_Addr *)*stack_base; + args = (Elf32_Auxargs *)imgp->auxargs; + pos = base + (imgp->argc + imgp->envc + 2); + + if (args->trace) + AUXARGS_ENTRY_32(pos, AT_DEBUG, 1); + if (args->execfd != -1) + AUXARGS_ENTRY_32(pos, AT_EXECFD, args->execfd); + AUXARGS_ENTRY_32(pos, AT_PHDR, args->phdr); + AUXARGS_ENTRY_32(pos, AT_PHENT, args->phent); + AUXARGS_ENTRY_32(pos, AT_PHNUM, args->phnum); + AUXARGS_ENTRY_32(pos, AT_PAGESZ, args->pagesz); + AUXARGS_ENTRY_32(pos, AT_FLAGS, args->flags); + AUXARGS_ENTRY_32(pos, AT_ENTRY, args->entry); + AUXARGS_ENTRY_32(pos, AT_BASE, args->base); + AUXARGS_ENTRY_32(pos, AT_UID, imgp->proc->p_ucred->cr_ruid); + AUXARGS_ENTRY_32(pos, AT_EUID, imgp->proc->p_ucred->cr_svuid); + AUXARGS_ENTRY_32(pos, AT_GID, imgp->proc->p_ucred->cr_rgid); + AUXARGS_ENTRY_32(pos, AT_EGID, imgp->proc->p_ucred->cr_svgid); + AUXARGS_ENTRY_32(pos, AT_NULL, 0); + + free(imgp->auxargs, M_TEMP); + imgp->auxargs = NULL; + + base--; + suword32(base, (uint32_t)imgp->argc); + *stack_base = (register_t *)base; + return 0; +} + +extern int _ucodesel, _ucode32sel, _udatasel; +extern unsigned long linux_sznonrtsigcode; + +static void +linux_rt_sendsig(sig_t catcher, int sig, sigset_t *mask, u_long code) +{ + struct thread *td = curthread; + struct proc *p = td->td_proc; + struct sigacts *psp; + struct trapframe *regs; + struct l_rt_sigframe *fp, frame; + int oonstack; + + PROC_LOCK_ASSERT(p, MA_OWNED); + psp = p->p_sigacts; + mtx_assert(&psp->ps_mtx, MA_OWNED); + regs = td->td_frame; + oonstack = sigonstack(regs->tf_rsp); + +#ifdef DEBUG + if (ldebug(rt_sendsig)) + printf(ARGS(rt_sendsig, "%p, %d, %p, %lu"), + catcher, sig, (void*)mask, code); +#endif + /* + * Allocate space for the signal handler context. + */ + if ((td->td_pflags & TDP_ALTSTACK) && !oonstack && + SIGISMEMBER(psp->ps_sigonstack, sig)) { + fp = (struct l_rt_sigframe *)(td->td_sigstk.ss_sp + + td->td_sigstk.ss_size - sizeof(struct l_rt_sigframe)); + } else + fp = (struct l_rt_sigframe *)regs->tf_rsp - 1; + mtx_unlock(&psp->ps_mtx); + + /* + * Build the argument list for the signal handler. + */ + if (p->p_sysent->sv_sigtbl) + if (sig <= p->p_sysent->sv_sigsize) + sig = p->p_sysent->sv_sigtbl[_SIG_IDX(sig)]; + + bzero(&frame, sizeof(frame)); + + frame.sf_handler = PTROUT(catcher); + frame.sf_sig = sig; + frame.sf_siginfo = PTROUT(&fp->sf_si); + frame.sf_ucontext = PTROUT(&fp->sf_sc); + + /* Fill in POSIX parts */ + frame.sf_si.lsi_signo = sig; + frame.sf_si.lsi_code = code; + frame.sf_si.lsi_addr = PTROUT(regs->tf_err); + + /* + * Build the signal context to be used by sigreturn. + */ + frame.sf_sc.uc_flags = 0; /* XXX ??? */ + frame.sf_sc.uc_link = 0; /* XXX ??? */ + + frame.sf_sc.uc_stack.ss_sp = PTROUT(td->td_sigstk.ss_sp); + frame.sf_sc.uc_stack.ss_size = td->td_sigstk.ss_size; + frame.sf_sc.uc_stack.ss_flags = (td->td_pflags & TDP_ALTSTACK) + ? ((oonstack) ? LINUX_SS_ONSTACK : 0) : LINUX_SS_DISABLE; + PROC_UNLOCK(p); + + bsd_to_linux_sigset(mask, &frame.sf_sc.uc_sigmask); + + frame.sf_sc.uc_mcontext.sc_mask = frame.sf_sc.uc_sigmask.__bits[0]; + frame.sf_sc.uc_mcontext.sc_gs = rgs(); + frame.sf_sc.uc_mcontext.sc_fs = rfs(); + __asm __volatile("movl %%es,%0" : + "=rm" (frame.sf_sc.uc_mcontext.sc_es)); + __asm __volatile("movl %%ds,%0" : + "=rm" (frame.sf_sc.uc_mcontext.sc_ds)); + frame.sf_sc.uc_mcontext.sc_edi = regs->tf_rdi; + frame.sf_sc.uc_mcontext.sc_esi = regs->tf_rsi; + frame.sf_sc.uc_mcontext.sc_ebp = regs->tf_rbp; + frame.sf_sc.uc_mcontext.sc_ebx = regs->tf_rbx; + frame.sf_sc.uc_mcontext.sc_edx = regs->tf_rdx; + frame.sf_sc.uc_mcontext.sc_ecx = regs->tf_rcx; + frame.sf_sc.uc_mcontext.sc_eax = regs->tf_rax; + frame.sf_sc.uc_mcontext.sc_eip = regs->tf_rip; + frame.sf_sc.uc_mcontext.sc_cs = regs->tf_cs; + frame.sf_sc.uc_mcontext.sc_eflags = regs->tf_rflags; + frame.sf_sc.uc_mcontext.sc_esp_at_signal = regs->tf_rsp; + frame.sf_sc.uc_mcontext.sc_ss = regs->tf_ss; + frame.sf_sc.uc_mcontext.sc_err = regs->tf_err; + frame.sf_sc.uc_mcontext.sc_trapno = bsd_to_linux_trapcode(code); + +#ifdef DEBUG + if (ldebug(rt_sendsig)) + printf(LMSG("rt_sendsig flags: 0x%x, sp: %p, ss: 0x%x, mask: 0x%x"), + frame.sf_sc.uc_stack.ss_flags, td->td_sigstk.ss_sp, + td->td_sigstk.ss_size, frame.sf_sc.uc_mcontext.sc_mask); +#endif + + if (copyout(&frame, fp, sizeof(frame)) != 0) { + /* + * Process has trashed its stack; give it an illegal + * instruction to halt it in its tracks. + */ +#ifdef DEBUG + if (ldebug(rt_sendsig)) + printf(LMSG("rt_sendsig: bad stack %p, oonstack=%x"), + fp, oonstack); +#endif + PROC_LOCK(p); + sigexit(td, SIGILL); + } + + /* + * Build context to run handler in. + */ + regs->tf_rsp = PTROUT(fp); + regs->tf_rip = LINUX32_PS_STRINGS - *(p->p_sysent->sv_szsigcode) + + linux_sznonrtsigcode; + regs->tf_rflags &= ~PSL_T; + regs->tf_cs = _ucode32sel; + regs->tf_ss = _udatasel; + load_ds(_udatasel); + td->td_pcb->pcb_ds = _udatasel; + load_es(_udatasel); + td->td_pcb->pcb_es = _udatasel; + PROC_LOCK(p); + mtx_lock(&psp->ps_mtx); +} + + +/* + * Send an interrupt to process. + * + * Stack is set up to allow sigcode stored + * in u. to call routine, followed by kcall + * to sigreturn routine below. After sigreturn + * resets the signal mask, the stack, and the + * frame pointer, it returns to the user + * specified pc, psl. + */ +static void +linux_sendsig(sig_t catcher, int sig, sigset_t *mask, u_long code) +{ + struct thread *td = curthread; + struct proc *p = td->td_proc; + struct sigacts *psp; + struct trapframe *regs; + struct l_sigframe *fp, frame; + l_sigset_t lmask; + int oonstack, i; + + PROC_LOCK_ASSERT(p, MA_OWNED); + psp = p->p_sigacts; + mtx_assert(&psp->ps_mtx, MA_OWNED); + if (SIGISMEMBER(psp->ps_siginfo, sig)) { + /* Signal handler installed with SA_SIGINFO. */ + linux_rt_sendsig(catcher, sig, mask, code); + return; + } + + regs = td->td_frame; + oonstack = sigonstack(regs->tf_rsp); + +#ifdef DEBUG + if (ldebug(sendsig)) + printf(ARGS(sendsig, "%p, %d, %p, %lu"), + catcher, sig, (void*)mask, code); +#endif + + /* + * Allocate space for the signal handler context. + */ + if ((td->td_pflags & TDP_ALTSTACK) && !oonstack && + SIGISMEMBER(psp->ps_sigonstack, sig)) { + fp = (struct l_sigframe *)(td->td_sigstk.ss_sp + + td->td_sigstk.ss_size - sizeof(struct l_sigframe)); + } else + fp = (struct l_sigframe *)regs->tf_rsp - 1; + mtx_unlock(&psp->ps_mtx); + PROC_UNLOCK(p); + + /* + * Build the argument list for the signal handler. + */ + if (p->p_sysent->sv_sigtbl) + if (sig <= p->p_sysent->sv_sigsize) + sig = p->p_sysent->sv_sigtbl[_SIG_IDX(sig)]; + + bzero(&frame, sizeof(frame)); + + frame.sf_handler = PTROUT(catcher); + frame.sf_sig = sig; + + bsd_to_linux_sigset(mask, &lmask); + + /* + * Build the signal context to be used by sigreturn. + */ + frame.sf_sc.sc_mask = lmask.__bits[0]; + frame.sf_sc.sc_gs = rgs(); + frame.sf_sc.sc_fs = rfs(); + __asm __volatile("movl %%es,%0" : "=rm" (frame.sf_sc.sc_es)); + __asm __volatile("movl %%ds,%0" : "=rm" (frame.sf_sc.sc_ds)); + frame.sf_sc.sc_edi = regs->tf_rdi; + frame.sf_sc.sc_esi = regs->tf_rsi; + frame.sf_sc.sc_ebp = regs->tf_rbp; + frame.sf_sc.sc_ebx = regs->tf_rbx; + frame.sf_sc.sc_edx = regs->tf_rdx; + frame.sf_sc.sc_ecx = regs->tf_rcx; + frame.sf_sc.sc_eax = regs->tf_rax; + frame.sf_sc.sc_eip = regs->tf_rip; + frame.sf_sc.sc_cs = regs->tf_cs; + frame.sf_sc.sc_eflags = regs->tf_rflags; + frame.sf_sc.sc_esp_at_signal = regs->tf_rsp; + frame.sf_sc.sc_ss = regs->tf_ss; + frame.sf_sc.sc_err = regs->tf_err; + frame.sf_sc.sc_trapno = bsd_to_linux_trapcode(code); + + for (i = 0; i < (LINUX_NSIG_WORDS-1); i++) + frame.sf_extramask[i] = lmask.__bits[i+1]; + + if (copyout(&frame, fp, sizeof(frame)) != 0) { + /* + * Process has trashed its stack; give it an illegal + * instruction to halt it in its tracks. + */ + PROC_LOCK(p); + sigexit(td, SIGILL); + } + + /* + * Build context to run handler in. + */ + regs->tf_rsp = PTROUT(fp); + regs->tf_rip = LINUX32_PS_STRINGS - *(p->p_sysent->sv_szsigcode); + regs->tf_rflags &= ~PSL_T; + regs->tf_cs = _ucode32sel; + regs->tf_ss = _udatasel; + load_ds(_udatasel); + td->td_pcb->pcb_ds = _udatasel; + load_es(_udatasel); + td->td_pcb->pcb_es = _udatasel; + PROC_LOCK(p); + mtx_lock(&psp->ps_mtx); +} + +/* + * System call to cleanup state after a signal + * has been taken. Reset signal mask and + * stack state from context left by sendsig (above). + * Return to previous pc and psl as specified by + * context left by sendsig. Check carefully to + * make sure that the user has not modified the + * psl to gain improper privileges or to cause + * a machine fault. + */ +int +linux_sigreturn(struct thread *td, struct linux_sigreturn_args *args) +{ + struct proc *p = td->td_proc; + struct l_sigframe frame; + struct trapframe *regs; + l_sigset_t lmask; + int eflags, i; + + regs = td->td_frame; + +#ifdef DEBUG + if (ldebug(sigreturn)) + printf(ARGS(sigreturn, "%p"), (void *)args->sfp); +#endif + /* + * The trampoline code hands us the sigframe. + * It is unsafe to keep track of it ourselves, in the event that a + * program jumps out of a signal handler. + */ + if (copyin(args->sfp, &frame, sizeof(frame)) != 0) + return (EFAULT); + + /* + * Check for security violations. + */ +#define EFLAGS_SECURE(ef, oef) ((((ef) ^ (oef)) & ~PSL_USERCHANGE) == 0) + eflags = frame.sf_sc.sc_eflags; + /* + * XXX do allow users to change the privileged flag PSL_RF. The + * cpu sets PSL_RF in tf_eflags for faults. Debuggers should + * sometimes set it there too. tf_eflags is kept in the signal + * context during signal handling and there is no other place + * to remember it, so the PSL_RF bit may be corrupted by the + * signal handler without us knowing. Corruption of the PSL_RF + * bit at worst causes one more or one less debugger trap, so + * allowing it is fairly harmless. + */ + if (!EFLAGS_SECURE(eflags & ~PSL_RF, regs->tf_rflags & ~PSL_RF)) + return(EINVAL); + + /* + * Don't allow users to load a valid privileged %cs. Let the + * hardware check for invalid selectors, excess privilege in + * other selectors, invalid %eip's and invalid %esp's. + */ +#define CS_SECURE(cs) (ISPL(cs) == SEL_UPL) + if (!CS_SECURE(frame.sf_sc.sc_cs)) { + trapsignal(td, SIGBUS, T_PROTFLT); + return(EINVAL); + } + + lmask.__bits[0] = frame.sf_sc.sc_mask; + for (i = 0; i < (LINUX_NSIG_WORDS-1); i++) + lmask.__bits[i+1] = frame.sf_extramask[i]; + PROC_LOCK(p); + linux_to_bsd_sigset(&lmask, &td->td_sigmask); + SIG_CANTMASK(td->td_sigmask); + signotify(td); + PROC_UNLOCK(p); + + /* + * Restore signal context. + */ + /* Selectors were restored by the trampoline. */ + regs->tf_rdi = frame.sf_sc.sc_edi; + regs->tf_rsi = frame.sf_sc.sc_esi; + regs->tf_rbp = frame.sf_sc.sc_ebp; + regs->tf_rbx = frame.sf_sc.sc_ebx; + regs->tf_rdx = frame.sf_sc.sc_edx; + regs->tf_rcx = frame.sf_sc.sc_ecx; + regs->tf_rax = frame.sf_sc.sc_eax; + regs->tf_rip = frame.sf_sc.sc_eip; + regs->tf_cs = frame.sf_sc.sc_cs; + regs->tf_rflags = eflags; + regs->tf_rsp = frame.sf_sc.sc_esp_at_signal; + regs->tf_ss = frame.sf_sc.sc_ss; + + return (EJUSTRETURN); +} + +/* + * System call to cleanup state after a signal + * has been taken. Reset signal mask and + * stack state from context left by rt_sendsig (above). + * Return to previous pc and psl as specified by + * context left by sendsig. Check carefully to + * make sure that the user has not modified the + * psl to gain improper privileges or to cause + * a machine fault. + */ +int +linux_rt_sigreturn(struct thread *td, struct linux_rt_sigreturn_args *args) +{ + struct proc *p = td->td_proc; + struct l_ucontext uc; + struct l_sigcontext *context; + l_stack_t *lss; + stack_t ss; + struct trapframe *regs; + int eflags; + + regs = td->td_frame; + +#ifdef DEBUG + if (ldebug(rt_sigreturn)) + printf(ARGS(rt_sigreturn, "%p"), (void *)args->ucp); +#endif + /* + * The trampoline code hands us the ucontext. + * It is unsafe to keep track of it ourselves, in the event that a + * program jumps out of a signal handler. + */ + if (copyin(args->ucp, &uc, sizeof(uc)) != 0) + return (EFAULT); + + context = &uc.uc_mcontext; + + /* + * Check for security violations. + */ +#define EFLAGS_SECURE(ef, oef) ((((ef) ^ (oef)) & ~PSL_USERCHANGE) == 0) + eflags = context->sc_eflags; + /* + * XXX do allow users to change the privileged flag PSL_RF. The + * cpu sets PSL_RF in tf_eflags for faults. Debuggers should + * sometimes set it there too. tf_eflags is kept in the signal + * context during signal handling and there is no other place + * to remember it, so the PSL_RF bit may be corrupted by the + * signal handler without us knowing. Corruption of the PSL_RF + * bit at worst causes one more or one less debugger trap, so + * allowing it is fairly harmless. + */ + if (!EFLAGS_SECURE(eflags & ~PSL_RF, regs->tf_rflags & ~PSL_RF)) + return(EINVAL); + + /* + * Don't allow users to load a valid privileged %cs. Let the + * hardware check for invalid selectors, excess privilege in + * other selectors, invalid %eip's and invalid %esp's. + */ +#define CS_SECURE(cs) (ISPL(cs) == SEL_UPL) + if (!CS_SECURE(context->sc_cs)) { + trapsignal(td, SIGBUS, T_PROTFLT); + return(EINVAL); + } + + PROC_LOCK(p); + linux_to_bsd_sigset(&uc.uc_sigmask, &td->td_sigmask); + SIG_CANTMASK(td->td_sigmask); + signotify(td); + PROC_UNLOCK(p); + + /* + * Restore signal context + */ + /* Selectors were restored by the trampoline. */ + regs->tf_rdi = context->sc_edi; + regs->tf_rsi = context->sc_esi; + regs->tf_rbp = context->sc_ebp; + regs->tf_rbx = context->sc_ebx; + regs->tf_rdx = context->sc_edx; + regs->tf_rcx = context->sc_ecx; + regs->tf_rax = context->sc_eax; + regs->tf_rip = context->sc_eip; + regs->tf_cs = context->sc_cs; + regs->tf_rflags = eflags; + regs->tf_rsp = context->sc_esp_at_signal; + regs->tf_ss = context->sc_ss; + + /* + * call sigaltstack & ignore results.. + */ + lss = &uc.uc_stack; + ss.ss_sp = PTRIN(lss->ss_sp); + ss.ss_size = lss->ss_size; + ss.ss_flags = linux_to_bsd_sigaltstack(lss->ss_flags); + +#ifdef DEBUG + if (ldebug(rt_sigreturn)) + printf(LMSG("rt_sigret flags: 0x%x, sp: %p, ss: 0x%x, mask: 0x%x"), + ss.ss_flags, ss.ss_sp, ss.ss_size, context->sc_mask); +#endif + (void)kern_sigaltstack(td, &ss, NULL); + + return (EJUSTRETURN); +} + +/* + * MPSAFE + */ +static void +linux_prepsyscall(struct trapframe *tf, int *args, u_int *code, caddr_t *params) +{ + args[0] = tf->tf_rbx; + args[1] = tf->tf_rcx; + args[2] = tf->tf_rdx; + args[3] = tf->tf_rsi; + args[4] = tf->tf_rdi; + args[5] = tf->tf_rbp; /* Unconfirmed */ + *params = NULL; /* no copyin */ +} + +/* + * If a linux binary is exec'ing something, try this image activator + * first. We override standard shell script execution in order to + * be able to modify the interpreter path. We only do this if a linux + * binary is doing the exec, so we do not create an EXEC module for it. + */ +static int exec_linux_imgact_try(struct image_params *iparams); + +static int +exec_linux_imgact_try(struct image_params *imgp) +{ + const char *head = (const char *)imgp->image_header; + int error = -1; + + /* + * The interpreter for shell scripts run from a linux binary needs + * to be located in /compat/linux if possible in order to recursively + * maintain linux path emulation. + */ + if (((const short *)head)[0] == SHELLMAGIC) { + /* + * Run our normal shell image activator. If it succeeds attempt + * to use the alternate path for the interpreter. If an alternate + * path is found, use our stringspace to store it. + */ + if ((error = exec_shell_imgact(imgp)) == 0) { + char *rpath = NULL; + + linux_emul_find(FIRST_THREAD_IN_PROC(imgp->proc), NULL, + imgp->interpreter_name, &rpath, 0); + if (rpath != imgp->interpreter_name) { + int len = strlen(rpath) + 1; + + if (len <= MAXSHELLCMDLEN) { + memcpy(imgp->interpreter_name, rpath, len); + } + free(rpath, M_TEMP); + } + } + } + return(error); +} + +/* + * Clear registers on exec + * XXX copied from ia32_signal.c. + */ +static void +exec_linux_setregs(td, entry, stack, ps_strings) + struct thread *td; + u_long entry; + u_long stack; + u_long ps_strings; +{ + struct trapframe *regs = td->td_frame; + struct pcb *pcb = td->td_pcb; + + wrmsr(MSR_FSBASE, 0); + wrmsr(MSR_KGSBASE, 0); /* User value while we're in the kernel */ + pcb->pcb_fsbase = 0; + pcb->pcb_gsbase = 0; + load_ds(_udatasel); + load_es(_udatasel); + load_fs(_udatasel); + load_gs(0); + pcb->pcb_ds = _udatasel; + pcb->pcb_es = _udatasel; + pcb->pcb_fs = _udatasel; + pcb->pcb_gs = 0; + + bzero((char *)regs, sizeof(struct trapframe)); + regs->tf_rip = entry; + regs->tf_rsp = stack; + regs->tf_rflags = PSL_USER | (regs->tf_rflags & PSL_T); + regs->tf_ss = _udatasel; + regs->tf_cs = _ucode32sel; + regs->tf_rbx = ps_strings; + load_cr0(rcr0() | CR0_MP | CR0_TS); + + /* Return via doreti so that we can change to a different %cs */ + pcb->pcb_flags |= PCB_FULLCTX; + td->td_retval[1] = 0; +} + +/* + * XXX copied from ia32_sysvec.c. + */ +static register_t * +linux_copyout_strings(struct image_params *imgp) +{ + int argc, envc; + u_int32_t *vectp; + char *stringp, *destp; + u_int32_t *stack_base; + struct linux32_ps_strings *arginfo; + int sigcodesz; + + /* + * Calculate string base and vector table pointers. + * Also deal with signal trampoline code for this exec type. + */ + arginfo = (struct linux32_ps_strings *)LINUX32_PS_STRINGS; + sigcodesz = *(imgp->proc->p_sysent->sv_szsigcode); + destp = (caddr_t)arginfo - sigcodesz - SPARE_USRSPACE - + roundup((ARG_MAX - imgp->stringspace), sizeof(char *)); + + /* + * install sigcode + */ + if (sigcodesz) + copyout(imgp->proc->p_sysent->sv_sigcode, + ((caddr_t)arginfo - sigcodesz), szsigcode); + + /* + * If we have a valid auxargs ptr, prepare some room + * on the stack. + */ + if (imgp->auxargs) { + /* + * 'AT_COUNT*2' is size for the ELF Auxargs data. This is for + * lower compatibility. + */ + imgp->auxarg_size = (imgp->auxarg_size) ? imgp->auxarg_size + : (AT_COUNT * 2); + /* + * The '+ 2' is for the null pointers at the end of each of + * the arg and env vector sets,and imgp->auxarg_size is room + * for argument of Runtime loader. + */ + vectp = (u_int32_t *) (destp - (imgp->argc + imgp->envc + 2 + + imgp->auxarg_size) * sizeof(u_int32_t)); + + } else + /* + * The '+ 2' is for the null pointers at the end of each of + * the arg and env vector sets + */ + vectp = (u_int32_t *) + (destp - (imgp->argc + imgp->envc + 2) * sizeof(u_int32_t)); + + /* + * vectp also becomes our initial stack base + */ + stack_base = vectp; + + stringp = imgp->stringbase; + argc = imgp->argc; + envc = imgp->envc; + /* + * Copy out strings - arguments and environment. + */ + copyout(stringp, destp, ARG_MAX - imgp->stringspace); + + /* + * Fill in "ps_strings" struct for ps, w, etc. + */ + suword32(&arginfo->ps_argvstr, (u_int32_t)(intptr_t)vectp); + suword32(&arginfo->ps_nargvstr, argc); + + /* + * Fill in argument portion of vector table. + */ + for (; argc > 0; --argc) { + suword32(vectp++, (u_int32_t)(intptr_t)destp); + while (*stringp++ != 0) + destp++; + destp++; + } + + /* a null vector table pointer separates the argp's from the envp's */ + suword32(vectp++, 0); + + suword32(&arginfo->ps_envstr, (u_int32_t)(intptr_t)vectp); + suword32(&arginfo->ps_nenvstr, envc); + + /* + * Fill in environment portion of vector table. + */ + for (; envc > 0; --envc) { + suword32(vectp++, (u_int32_t)(intptr_t)destp); + while (*stringp++ != 0) + destp++; + destp++; + } + + /* end of vector table is a null pointer */ + suword32(vectp, 0); + + return ((register_t *)stack_base); +} + +SYSCTL_NODE(_compat, OID_AUTO, linux32, CTLFLAG_RW, 0, + "32-bit Linux emulation"); + +static u_long linux32_maxdsiz = LINUX32_MAXDSIZ; +SYSCTL_ULONG(_compat_linux32, OID_AUTO, maxdsiz, CTLFLAG_RW, + &linux32_maxdsiz, 0, ""); +static u_long linux32_maxssiz = LINUX32_MAXSSIZ; +SYSCTL_ULONG(_compat_linux32, OID_AUTO, maxssiz, CTLFLAG_RW, + &linux32_maxssiz, 0, ""); +static u_long linux32_maxvmem = LINUX32_MAXVMEM; +SYSCTL_ULONG(_compat_linux32, OID_AUTO, maxvmem, CTLFLAG_RW, + &linux32_maxvmem, 0, ""); + +/* + * XXX copied from ia32_sysvec.c. + */ +static void +linux32_fixlimits(struct image_params *imgp) +{ + struct proc *p = imgp->proc; + struct plimit *oldlim, *newlim; + + if (linux32_maxdsiz == 0 && linux32_maxssiz == 0 && + linux32_maxvmem == 0) + return; + newlim = lim_alloc(); + PROC_LOCK(p); + oldlim = p->p_limit; + lim_copy(newlim, oldlim); + if (linux32_maxdsiz != 0) { + if (newlim->pl_rlimit[RLIMIT_DATA].rlim_cur > linux32_maxdsiz) + newlim->pl_rlimit[RLIMIT_DATA].rlim_cur = linux32_maxdsiz; + if (newlim->pl_rlimit[RLIMIT_DATA].rlim_max > linux32_maxdsiz) + newlim->pl_rlimit[RLIMIT_DATA].rlim_max = linux32_maxdsiz; + } + if (linux32_maxssiz != 0) { + if (newlim->pl_rlimit[RLIMIT_STACK].rlim_cur > linux32_maxssiz) + newlim->pl_rlimit[RLIMIT_STACK].rlim_cur = linux32_maxssiz; + if (newlim->pl_rlimit[RLIMIT_STACK].rlim_max > linux32_maxssiz) + newlim->pl_rlimit[RLIMIT_STACK].rlim_max = linux32_maxssiz; + } + if (linux32_maxvmem != 0) { + if (newlim->pl_rlimit[RLIMIT_VMEM].rlim_cur > linux32_maxvmem) + newlim->pl_rlimit[RLIMIT_VMEM].rlim_cur = linux32_maxvmem; + if (newlim->pl_rlimit[RLIMIT_VMEM].rlim_max > linux32_maxvmem) + newlim->pl_rlimit[RLIMIT_VMEM].rlim_max = linux32_maxvmem; + } + p->p_limit = newlim; + PROC_UNLOCK(p); + lim_free(oldlim); +} + +struct sysentvec elf_linux_sysvec = { + LINUX_SYS_MAXSYSCALL, + linux_sysent, + 0xff, + LINUX_SIGTBLSZ, + bsd_to_linux_signal, + ELAST + 1, + bsd_to_linux_errno, + translate_traps, + elf_linux_fixup, + linux_sendsig, + linux_sigcode, + &linux_szsigcode, + linux_prepsyscall, + "Linux ELF32", + elf32_coredump, + exec_linux_imgact_try, + LINUX_MINSIGSTKSZ, + PAGE_SIZE, + VM_MIN_ADDRESS, + LINUX32_USRSTACK, + LINUX32_USRSTACK, + LINUX32_PS_STRINGS, + VM_PROT_ALL, + linux_copyout_strings, + exec_linux_setregs, + linux32_fixlimits +}; + +static Elf32_Brandinfo linux_brand = { + ELFOSABI_LINUX, + EM_386, + "Linux", + "/compat/linux", + "/lib/ld-linux.so.1", + &elf_linux_sysvec, + NULL, + }; + +static Elf32_Brandinfo linux_glibc2brand = { + ELFOSABI_LINUX, + EM_386, + "Linux", + "/compat/linux", + "/lib/ld-linux.so.2", + &elf_linux_sysvec, + NULL, + }; + +Elf32_Brandinfo *linux_brandlist[] = { + &linux_brand, + &linux_glibc2brand, + NULL + }; + +static int +linux_elf_modevent(module_t mod, int type, void *data) +{ + Elf32_Brandinfo **brandinfo; + int error; + struct linux_ioctl_handler **lihp; + + error = 0; + + switch(type) { + case MOD_LOAD: + for (brandinfo = &linux_brandlist[0]; *brandinfo != NULL; + ++brandinfo) + if (elf32_insert_brand_entry(*brandinfo) < 0) + error = EINVAL; + if (error == 0) { + SET_FOREACH(lihp, linux_ioctl_handler_set) + linux_ioctl_register_handler(*lihp); + if (bootverbose) + printf("Linux ELF exec handler installed\n"); + } else + printf("cannot insert Linux ELF brand handler\n"); + break; + case MOD_UNLOAD: + for (brandinfo = &linux_brandlist[0]; *brandinfo != NULL; + ++brandinfo) + if (elf32_brand_inuse(*brandinfo)) + error = EBUSY; + if (error == 0) { + for (brandinfo = &linux_brandlist[0]; + *brandinfo != NULL; ++brandinfo) + if (elf32_remove_brand_entry(*brandinfo) < 0) + error = EINVAL; + } + if (error == 0) { + SET_FOREACH(lihp, linux_ioctl_handler_set) + linux_ioctl_unregister_handler(*lihp); + if (bootverbose) + printf("Linux ELF exec handler removed\n"); + linux_mib_destroy(); + } else + printf("Could not deinstall ELF interpreter entry\n"); + break; + default: + break; + } + return error; +} + +static moduledata_t linux_elf_mod = { + "linuxelf", + linux_elf_modevent, + 0 +}; + +DECLARE_MODULE(linuxelf, linux_elf_mod, SI_SUB_EXEC, SI_ORDER_ANY); |
