/* * Copyright (c) 2013-2019, Huawei Technologies Co., Ltd. All rights reserved. * Copyright (c) 2020, Huawei Device Co., Ltd. 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. * * 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. Neither the name of the copyright holder nor the names of its contributors may be used * to endorse or promote products derived from this software without specific prior written * permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "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 COPYRIGHT HOLDER OR * CONTRIBUTORS 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 "los_signal.h" #include "pthread.h" #include "los_process_pri.h" #include "los_hw_pri.h" #include "user_copy.h" #ifdef LOSCFG_SECURITY_CAPABILITY #include "capability_api.h" #endif #ifdef __cplusplus #if __cplusplus extern "C" { #endif /* __cplusplus */ #endif /* __cplusplus */ int raise(int sig) { (VOID)sig; PRINT_ERR("%s NOT SUPPORT\n", __FUNCTION__); errno = ENOSYS; return -1; } #define GETUNMASKSET(procmask, pendFlag) ((~(procmask)) & (sigset_t)(pendFlag)) #define UINT64_BIT_SIZE 64 int OsSigIsMember(const sigset_t *set, int signo) { int ret = LOS_NOK; /* In musl, sig No bits 00000100 present sig No 3, but 1<< 3 = 00001000, so signo needs minus 1 */ signo -= 1; /* Verify the signal */ if (GOOD_SIGNO(signo)) { /* Check if the signal is in the set */ ret = ((*set & SIGNO2SET((unsigned int)signo)) != 0); } return ret; } int OsTcbDispatch(LosTaskCB *stcb, siginfo_t *info) { bool masked = FALSE; sig_cb *sigcb = &stcb->sig; OS_RETURN_IF_NULL(sigcb); /* If signo is 0, not send signal, just check process or pthread exist */ if (info->si_signo == 0) { return 0; } masked = (bool)OsSigIsMember(&sigcb->sigprocmask, info->si_signo); if (masked) { /* If signal is in wait list and mask list, need unblock it */ if (!LOS_ListEmpty(&sigcb->waitList) && OsSigIsMember(&sigcb->sigwaitmask, info->si_signo)) { OsTaskWake(stcb); OsSigEmptySet(&sigcb->sigwaitmask); } else { OsSigAddSet(&sigcb->sigPendFlag, info->si_signo); } } else { /* unmasked signal actions */ OsSigAddSet(&sigcb->sigFlag, info->si_signo); if (!LOS_ListEmpty(&sigcb->waitList) && OsSigIsMember(&sigcb->sigwaitmask, info->si_signo)) { OsTaskWake(stcb); OsSigEmptySet(&sigcb->sigwaitmask); } } (void) memcpy_s(&sigcb->sigunbinfo, sizeof(siginfo_t), info, sizeof(siginfo_t)); return 0; } void OsSigMaskSwitch(LosTaskCB * const rtcb, sigset_t set) { sigset_t unmaskset; rtcb->sig.sigprocmask = set; unmaskset = GETUNMASKSET(rtcb->sig.sigprocmask, rtcb->sig.sigPendFlag); if (unmaskset != NULL_SIGNAL_SET) { /* pendlist do */ rtcb->sig.sigFlag |= unmaskset; rtcb->sig.sigPendFlag ^= unmaskset; } } int OsSigprocMask(int how, const sigset_t_l *setl, sigset_t_l *oldset) { LosTaskCB *spcb = NULL; sigset_t oldSigprocmask; int ret = LOS_OK; unsigned int intSave; sigset_t set; int retVal; if (setl != NULL) { retVal = LOS_ArchCopyFromUser(&set, &(setl->sig[0]), sizeof(sigset_t)); if (retVal != 0) { return -EFAULT; } } SCHEDULER_LOCK(intSave); spcb = OsCurrTaskGet(); /* If requested, copy the old mask to user. */ oldSigprocmask = spcb->sig.sigprocmask; /* If requested, modify the current signal mask. */ if (setl != NULL) { /* Okay, determine what we are supposed to do */ switch (how) { /* Set the union of the current set and the signal * set pointed to by set as the new sigprocmask. */ case SIG_BLOCK: spcb->sig.sigprocmask |= set; break; /* Set the intersection of the current set and the * signal set pointed to by set as the new sigprocmask. */ case SIG_UNBLOCK: spcb->sig.sigprocmask &= ~(set); break; /* Set the signal set pointed to by set as the new sigprocmask. */ case SIG_SETMASK: spcb->sig.sigprocmask = set; break; default: ret = -EINVAL; break; } /* If pending mask not in sigmask, need set sigflag. */ OsSigMaskSwitch(spcb, spcb->sig.sigprocmask); } SCHEDULER_UNLOCK(intSave); if (oldset != NULL) { retVal = LOS_ArchCopyToUser(&(oldset->sig[0]), &oldSigprocmask, sizeof(sigset_t)); if (retVal != 0) { return -EFAULT; } } return ret; } int OsSigProcessForeachChild(LosProcessCB *spcb, ForEachTaskCB handler, void *arg) { int ret; /* Visit the main thread last (if present) */ LosTaskCB *taskCB = NULL; LOS_DL_LIST_FOR_EACH_ENTRY(taskCB, &(spcb->threadSiblingList), LosTaskCB, threadList) { ret = handler(taskCB, arg); OS_RETURN_IF(ret != 0, ret); } return LOS_OK; } static int SigProcessSignalHandler(LosTaskCB *tcb, void *arg) { struct ProcessSignalInfo *info = (struct ProcessSignalInfo *)arg; int ret; int isMember; if (tcb == NULL) { return 0; } /* If the default tcb is not setted, then set this one as default. */ if (!info->defaultTcb) { info->defaultTcb = tcb; } isMember = OsSigIsMember(&tcb->sig.sigwaitmask, info->sigInfo->si_signo); if (isMember && (!info->awakenedTcb)) { /* This means the task is waiting for this signal. Stop looking for it and use this tcb. * The requirement is: if more than one task in this task group is waiting for the signal, * then only one indeterminate task in the group will receive the signal. */ ret = OsTcbDispatch(tcb, info->sigInfo); OS_RETURN_IF(ret < 0, ret); /* set this tcb as awakenedTcb */ info->awakenedTcb = tcb; OS_RETURN_IF(info->receivedTcb != NULL, SIG_STOP_VISIT); /* Stop search */ } /* Is this signal unblocked on this thread? */ isMember = OsSigIsMember(&tcb->sig.sigprocmask, info->sigInfo->si_signo); if ((!isMember) && (!info->receivedTcb) && (tcb != info->awakenedTcb)) { /* if unblockedTcb of this signal is not setted, then set it. */ if (!info->unblockedTcb) { info->unblockedTcb = tcb; } ret = OsTcbDispatch(tcb, info->sigInfo); OS_RETURN_IF(ret < 0, ret); /* set this tcb as receivedTcb */ info->receivedTcb = tcb; OS_RETURN_IF(info->awakenedTcb != NULL, SIG_STOP_VISIT); /* Stop search */ } return 0; /* Keep searching */ } static int SigProcessKillSigHandler(LosTaskCB *tcb, void *arg) { struct ProcessSignalInfo *info = (struct ProcessSignalInfo *)arg; if ((tcb != NULL) && (info != NULL) && (info->sigInfo != NULL)) { sig_cb *sigcb = &tcb->sig; if (!LOS_ListEmpty(&sigcb->waitList) && OsSigIsMember(&sigcb->sigwaitmask, info->sigInfo->si_signo)) { OsTaskWake(tcb); OsSigEmptySet(&sigcb->sigwaitmask); } } return 0; } static void SigProcessLoadTcb(struct ProcessSignalInfo *info, siginfo_t *sigInfo) { LosTaskCB *tcb = NULL; if (info->awakenedTcb == NULL && info->receivedTcb == NULL) { if (info->unblockedTcb) { tcb = info->unblockedTcb; } else if (info->defaultTcb) { tcb = info->defaultTcb; } else { return; } /* Deliver the signal to the selected task */ (void)OsTcbDispatch(tcb, sigInfo); } } int OsSigProcessSend(LosProcessCB *spcb, siginfo_t *sigInfo) { int ret; struct ProcessSignalInfo info = { .sigInfo = sigInfo, .defaultTcb = NULL, .unblockedTcb = NULL, .awakenedTcb = NULL, .receivedTcb = NULL }; /* visit all taskcb and dispatch signal */ if ((info.sigInfo != NULL) && (info.sigInfo->si_signo == SIGKILL)) { (void)OsSigProcessForeachChild(spcb, SigProcessKillSigHandler, &info); OsSigAddSet(&spcb->sigShare, info.sigInfo->si_signo); OsWaitSignalToWakeProcess(spcb); return 0; } else { ret = OsSigProcessForeachChild(spcb, SigProcessSignalHandler, &info); } if (ret < 0) { return ret; } SigProcessLoadTcb(&info, sigInfo); return 0; } int OsSigEmptySet(sigset_t *set) { *set = NULL_SIGNAL_SET; return 0; } /* Privilege process can't send to kernel and privilege process */ static int OsSignalPermissionToCheck(const LosProcessCB *spcb) { UINT32 gid = spcb->group->groupID; if (gid == OS_KERNEL_PROCESS_GROUP) { return -EPERM; } else if (gid == OS_USER_PRIVILEGE_PROCESS_GROUP) { return -EPERM; } return 0; } int OsDispatch(pid_t pid, siginfo_t *info, int permission) { LosProcessCB *spcb = OS_PCB_FROM_PID(pid); if (OsProcessIsUnused(spcb)) { return -ESRCH; } #ifdef LOSCFG_SECURITY_CAPABILITY LosProcessCB *current = OsCurrProcessGet(); /* If the process you want to kill had been inactive, but still exist. should return LOS_OK */ if (OsProcessIsInactive(spcb)) { return LOS_OK; } /* Kernel process always has kill permission and user process should check permission */ if (OsProcessIsUserMode(current) && !(current->processStatus & OS_PROCESS_FLAG_EXIT)) { if ((current != spcb) && (!IsCapPermit(CAP_KILL)) && (current->user->userID != spcb->user->userID)) { return -EPERM; } } #endif if ((permission == OS_USER_KILL_PERMISSION) && (OsSignalPermissionToCheck(spcb) < 0)) { return -EPERM; } return OsSigProcessSend(spcb, info); } int OsKill(pid_t pid, int sig, int permission) { siginfo_t info; int ret; /* Make sure that the para is valid */ if (!GOOD_SIGNO(sig) || pid < 0) { return -EINVAL; } if (OsProcessIDUserCheckInvalid(pid)) { return -ESRCH; } /* Create the siginfo structure */ info.si_signo = sig; info.si_code = SI_USER; info.si_value.sival_ptr = NULL; /* Send the signal */ ret = OsDispatch(pid, &info, permission); return ret; } int OsKillLock(pid_t pid, int sig) { int ret; unsigned int intSave; SCHEDULER_LOCK(intSave); ret = OsKill(pid, sig, OS_USER_KILL_PERMISSION); SCHEDULER_UNLOCK(intSave); return ret; } int OsPthreadKill(UINT32 tid, int signo) { LosTaskCB *stcb = NULL; siginfo_t info; int ret; UINT32 intSave; /* Make sure that the signal is valid */ OS_RETURN_IF(!GOOD_SIGNO(signo), -EINVAL); if (OS_TID_CHECK_INVALID(tid)) { return -ESRCH; } /* Create the siginfo structure */ info.si_signo = signo; info.si_code = SI_USER; info.si_value.sival_ptr = NULL; /* Keep things stationary through the following */ SCHEDULER_LOCK(intSave); /* Get the TCB associated with the thread */ stcb = OsGetTaskCB(tid); OS_GOTO_EXIT_IF(stcb == NULL, -ESRCH); ret = OsUserTaskOperatePermissionsCheck(stcb); OS_GOTO_EXIT_IF(ret != LOS_OK, -ret); /* Dispatch the signal to thread, bypassing normal task group thread * dispatch rules. */ ret = OsTcbDispatch(stcb, &info); EXIT: SCHEDULER_UNLOCK(intSave); return ret; } int OsSigAddSet(sigset_t *set, int signo) { /* Verify the signal */ if (!GOOD_SIGNO(signo)) { return -EINVAL; } else { /* In musl, sig No bits 00000100 present sig No 3, but 1<< 3 = 00001000, so signo needs minus 1 */ signo -= 1; /* Add the signal to the set */ *set |= SIGNO2SET((unsigned int)signo); return LOS_OK; } } int OsSigPending(sigset_t *set) { LosTaskCB *tcb = NULL; unsigned int intSave; if (set == NULL) { return -EFAULT; } SCHEDULER_LOCK(intSave); tcb = OsCurrTaskGet(); *set = tcb->sig.sigPendFlag; SCHEDULER_UNLOCK(intSave); return LOS_OK; } STATIC int FindFirstSetedBit(UINT64 n) { int count; if (n == 0) { return -1; } for (count = 0; (count < UINT64_BIT_SIZE) && (n ^ 1ULL); n >>= 1, count++) {} return (count < UINT64_BIT_SIZE) ? count : (-1); } int OsSigTimedWaitNoLock(sigset_t *set, siginfo_t *info, unsigned int timeout) { LosTaskCB *task = NULL; sig_cb *sigcb = NULL; int ret; task = OsCurrTaskGet(); sigcb = &task->sig; if (sigcb->waitList.pstNext == NULL) { LOS_ListInit(&sigcb->waitList); } /* If pendingflag & set > 0, shound clear pending flag */ sigset_t clear = sigcb->sigPendFlag & *set; if (clear) { ret = FindFirstSetedBit((UINT64)clear) + 1; sigcb->sigPendFlag ^= SIGNO2SET(ret); } else { OsSigAddSet(set, SIGKILL); OsSigAddSet(set, SIGSTOP); sigcb->sigwaitmask |= *set; ret = OsTaskWait(&sigcb->waitList, timeout, TRUE); if (ret == LOS_ERRNO_TSK_TIMEOUT) { ret = -EAGAIN; } sigcb->sigwaitmask = NULL_SIGNAL_SET; } if (info != NULL) { (void) memcpy_s(info, sizeof(siginfo_t), &sigcb->sigunbinfo, sizeof(siginfo_t)); } return ret; } int OsSigTimedWait(sigset_t *set, siginfo_t *info, unsigned int timeout) { int ret; unsigned int intSave; SCHEDULER_LOCK(intSave); ret = OsSigTimedWaitNoLock(set, info, timeout); SCHEDULER_UNLOCK(intSave); return ret; } int OsPause(void) { LosTaskCB *spcb = NULL; sigset_t oldSigprocmask; spcb = OsCurrTaskGet(); oldSigprocmask = spcb->sig.sigprocmask; return OsSigSuspend(&oldSigprocmask); } int OsSigSuspend(const sigset_t *set) { unsigned int intSave; LosTaskCB *rtcb = NULL; unsigned int sigTempProcMask; sigset_t setSuspend; int ret; if (set == NULL) { return -EINVAL; } SCHEDULER_LOCK(intSave); rtcb = OsCurrTaskGet(); sigTempProcMask = rtcb->sig.sigprocmask; /* Wait signal calc */ setSuspend = FULL_SIGNAL_SET & (~(*set)); /* If pending mask not in sigmask, need set sigflag */ OsSigMaskSwitch(rtcb, *set); ret = OsSigTimedWaitNoLock(&setSuspend, NULL, LOS_WAIT_FOREVER); if (ret < 0) { PRINT_ERR("FUNC %s LINE = %d, ret = %x\n", __FUNCTION__, __LINE__, ret); } /* Restore old sigprocmask */ OsSigMaskSwitch(rtcb, sigTempProcMask); SCHEDULER_UNLOCK(intSave); return -EINTR; } int OsSigAction(int sig, const sigaction_t *act, sigaction_t *oact) { UINTPTR addr; sigaction_t action; if (!GOOD_SIGNO(sig) || sig < 1 || act == NULL) { return -EINVAL; } if (LOS_ArchCopyFromUser(&action, act, sizeof(sigaction_t)) != LOS_OK) { return -EFAULT; } if (sig == SIGSYS) { addr = OsGetSigHandler(); if (addr == 0) { OsSetSigHandler((unsigned long)(UINTPTR)action.sa_handler); return LOS_OK; } return -EINVAL; } return LOS_OK; } void OsSaveSignalContext(unsigned int *sp) { UINTPTR sigHandler; UINT32 intSave; LosTaskCB *task = NULL; LosProcessCB *process = NULL; sig_cb *sigcb = NULL; unsigned long cpsr; OS_RETURN_IF_VOID(sp == NULL); cpsr = OS_SYSCALL_GET_CPSR(sp); OS_RETURN_IF_VOID(((cpsr & CPSR_MASK_MODE) != CPSR_USER_MODE)); SCHEDULER_LOCK(intSave); task = OsCurrTaskGet(); process = OsCurrProcessGet(); sigcb = &task->sig; if ((sigcb->context.count == 0) && ((sigcb->sigFlag != 0) || (process->sigShare != 0))) { sigHandler = OsGetSigHandler(); if (sigHandler == 0) { sigcb->sigFlag = 0; process->sigShare = 0; SCHEDULER_UNLOCK(intSave); PRINT_ERR("The signal processing function for the current process pid =%d is NULL!\n", task->processID); return; } /* One pthread do the share signal */ sigcb->sigFlag |= process->sigShare; unsigned int signo = (unsigned int)FindFirstSetedBit(sigcb->sigFlag) + 1; OsProcessExitCodeSignalSet(process, signo); sigcb->context.CPSR = cpsr; sigcb->context.PC = sp[REG_PC]; sigcb->context.USP = sp[REG_SP]; sigcb->context.ULR = sp[REG_LR]; sigcb->context.R0 = sp[REG_R0]; sigcb->context.R1 = sp[REG_R1]; sigcb->context.R2 = sp[REG_R2]; sigcb->context.R3 = sp[REG_R3]; sigcb->context.R7 = sp[REG_R7]; sigcb->context.R12 = sp[REG_R12]; sp[REG_PC] = sigHandler; sp[REG_R0] = signo; sp[REG_R1] = (unsigned int)(UINTPTR)(sigcb->sigunbinfo.si_value.sival_ptr); /* sig No bits 00000100 present sig No 3, but 1<< 3 = 00001000, so signo needs minus 1 */ sigcb->sigFlag ^= 1ULL << (signo - 1); sigcb->context.count++; } SCHEDULER_UNLOCK(intSave); } void OsSaveSignalContextIrq(unsigned int *sp, unsigned int r7) { UINTPTR sigHandler; LosTaskCB *task = NULL; LosProcessCB *process = NULL; sig_cb *sigcb = NULL; unsigned long cpsr; UINT32 intSave; TaskIrqContext *context = (TaskIrqContext *)(sp); OS_RETURN_IF_VOID(sp == NULL); cpsr = context->CPSR; OS_RETURN_IF_VOID(((cpsr & CPSR_MASK_MODE) != CPSR_USER_MODE)); SCHEDULER_LOCK(intSave); task = OsCurrTaskGet(); process = OsCurrProcessGet(); sigcb = &task->sig; if ((sigcb->context.count == 0) && ((sigcb->sigFlag != 0) || (process->sigShare != 0))) { sigHandler = OsGetSigHandler(); if (sigHandler == 0) { sigcb->sigFlag = 0; process->sigShare = 0; SCHEDULER_UNLOCK(intSave); PRINT_ERR("The current process pid =%d starts fail!\n", task->processID); return; } sigcb->sigFlag |= process->sigShare; unsigned int signo = (unsigned int)FindFirstSetedBit(sigcb->sigFlag) + 1; OsProcessExitCodeSignalSet(process, signo); (VOID)memcpy_s(&sigcb->context.R0, sizeof(TaskIrqDataSize), &context->R0, sizeof(TaskIrqDataSize)); sigcb->context.R7 = r7; context->PC = sigHandler; context->R0 = signo; context->R1 = (UINT32)(UINTPTR)sigcb->sigunbinfo.si_value.sival_ptr; /* sig No bits 00000100 present sig No 3, but 1<< 3 = 00001000, so signo needs minus 1 */ sigcb->sigFlag ^= 1ULL << (signo - 1); sigcb->context.count++; } SCHEDULER_UNLOCK(intSave); } void OsRestorSignalContext(unsigned int *sp) { LosTaskCB *task = NULL; /* Do not adjust this statement */ LosProcessCB *process = NULL; sig_cb *sigcb = NULL; UINT32 intSave; SCHEDULER_LOCK(intSave); task = OsCurrTaskGet(); sigcb = &task->sig; if (sigcb->context.count != 1) { SCHEDULER_UNLOCK(intSave); PRINT_ERR("sig error count : %d\n", sigcb->context.count); return; } process = OsCurrProcessGet(); sp[REG_PC] = sigcb->context.PC; OS_SYSCALL_SET_CPSR(sp, sigcb->context.CPSR); sp[REG_SP] = sigcb->context.USP; sp[REG_LR] = sigcb->context.ULR; sp[REG_R0] = sigcb->context.R0; sp[REG_R1] = sigcb->context.R1; sp[REG_R2] = sigcb->context.R2; sp[REG_R3] = sigcb->context.R3; sp[REG_R7] = sigcb->context.R7; sp[REG_R12] = sigcb->context.R12; sigcb->context.count--; process->sigShare = 0; OsProcessExitCodeSignalClear(process); SCHEDULER_UNLOCK(intSave); } #ifdef __cplusplus #if __cplusplus } #endif /* __cplusplus */ #endif /* __cplusplus */