github.com/SagerNet/gvisor@v0.0.0-20210707092255-7731c139d75c/test/syscalls/linux/processes.cc (about)

     1  // Copyright 2021 The gVisor Authors.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  #include <stdint.h>
    16  #include <sys/syscall.h>
    17  #include <unistd.h>
    18  
    19  #include "test/util/capability_util.h"
    20  #include "test/util/test_util.h"
    21  
    22  namespace gvisor {
    23  namespace testing {
    24  
    25  int testSetPGIDOfZombie(void* arg) {
    26    int p[2];
    27  
    28    TEST_PCHECK(pipe(p) == 0);
    29  
    30    pid_t pid = fork();
    31    if (pid == 0) {
    32      pid = fork();
    33      // Create a second child to repeat one of syzkaller reproducers.
    34      if (pid == 0) {
    35        pid = getpid();
    36        TEST_PCHECK(setpgid(pid, 0) == 0);
    37        TEST_PCHECK(write(p[1], &pid, sizeof(pid)) == sizeof(pid));
    38        _exit(0);
    39      }
    40      TEST_PCHECK(pid > 0);
    41      _exit(0);
    42    }
    43    close(p[1]);
    44    TEST_PCHECK(pid > 0);
    45  
    46    // Get PID of the second child.
    47    pid_t cpid;
    48    TEST_PCHECK(read(p[0], &cpid, sizeof(cpid)) == sizeof(cpid));
    49  
    50    // Wait when both child processes will die.
    51    int c;
    52    TEST_PCHECK(read(p[0], &c, sizeof(c)) == 0);
    53  
    54    // Wait the second child process to collect its zombie.
    55    int status;
    56    TEST_PCHECK(RetryEINTR(waitpid)(cpid, &status, 0) == cpid);
    57  
    58    // Set the child's group.
    59    TEST_PCHECK(setpgid(pid, pid) == 0);
    60  
    61    TEST_PCHECK(RetryEINTR(waitpid)(-pid, &status, 0) == pid);
    62  
    63    TEST_PCHECK(status == 0);
    64    _exit(0);
    65  }
    66  
    67  TEST(Processes, SetPGIDOfZombie) {
    68    SKIP_IF(!ASSERT_NO_ERRNO_AND_VALUE(HaveCapability(CAP_SYS_ADMIN)));
    69  
    70    // Fork a test process in a new PID namespace, because it needs to manipulate
    71    // with reparanted processes.
    72    struct clone_arg {
    73      // Reserve some space for clone() to locate arguments and retcode in this
    74      // place.
    75      char stack[128] __attribute__((aligned(16)));
    76      char stack_ptr[0];
    77    } ca;
    78    pid_t pid;
    79    ASSERT_THAT(pid = clone(testSetPGIDOfZombie, ca.stack_ptr,
    80                            CLONE_NEWPID | SIGCHLD, &ca),
    81                SyscallSucceeds());
    82  
    83    int status;
    84    ASSERT_THAT(RetryEINTR(waitpid)(pid, &status, 0),
    85                SyscallSucceedsWithValue(pid));
    86    EXPECT_EQ(status, 0);
    87  }
    88  
    89  }  // namespace testing
    90  }  // namespace gvisor