From: Sukadev Bhattiprolu <[email protected]> Date: Sat, 30 Jan 2010 12:51:23 -0800 Subject: [PATCH 2/6]: eclone-2: Fail if selected pid is in use
Ensure that eclone() system call fails with -EBUSY if selected pid is in use. Signed-off-by: Sukadev Bhattiprolu <[email protected]> --- eclone/Makefile | 2 +- eclone/eclone-2.c | 117 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 118 insertions(+), 1 deletions(-) create mode 100644 eclone/eclone-2.c diff --git a/eclone/Makefile b/eclone/Makefile index 43cef65..95633d1 100644 --- a/eclone/Makefile +++ b/eclone/Makefile @@ -3,7 +3,7 @@ CFLAGS = -Wall LDFLAGS = -PROGS = eclone-1 +PROGS = eclone-1 eclone-2 all: $(PROGS) diff --git a/eclone/eclone-2.c b/eclone/eclone-2.c new file mode 100644 index 0000000..a52bb5e --- /dev/null +++ b/eclone/eclone-2.c @@ -0,0 +1,117 @@ +#include <stdio.h> +#include <stdlib.h> +#include <errno.h> +#include <unistd.h> +#include <signal.h> +#include <string.h> +#include <sys/types.h> +#include <sys/wait.h> +#include <sys/syscall.h> +#include "clone_args.h" + +/* + * Verify that eclone() fails if the selected pid is in use. + * We try to assign parent's pid which should already be in use. + */ +int verbose = 0; +int child_tid, parent_tid; +#define CHILD_ARG (void *)0x979797 + +pid_t pids_list[2]; + +int do_child(void *arg) +{ + printf("FAIL: Child created with [%d, %d], but we expected child " + "creation to fail since pid is in use\n", gettid(), + getpid()); + exit(2); +} + +static int myclone(int (*child_fn)(void *), void *child_arg, + unsigned int flags_low, int nr_pids, pid_t *pids_list) +{ + int rc; + void *stack; + struct clone_args ca; + int args_size; + + stack = setup_stack(child_fn, child_arg, STACKSIZE); + if (!stack) { + printf("ERROR: setup_stack returns NULL for size %d\n", + STACKSIZE); + exit(1); + } + + memset(&ca, 0, sizeof(ca)); + ca.child_stack_base = (u64)(int)stack; + ca.child_stack_size = (u64)0; + ca.parent_tid_ptr = (u64)((int)&parent_tid); + ca.child_tid_ptr = (u64)((int)&child_tid); + ca.nr_pids = nr_pids; + + if (verbose) { + printf("[%d, %d]: Parent:\n\t child_stack 0x%p, ptidp %llx, " + "ctidp %llx, pids %p\n", getpid(), gettid(), + stack, ca.parent_tid_ptr, ca.child_tid_ptr, + pids_list); + } + + args_size = sizeof(struct clone_args); + rc = eclone(flags_low, &ca, args_size, pids_list); + + if (verbose) { + printf("[%d, %d]: eclone() returned %d, error %d\n", getpid(), + gettid(), rc, errno); + fflush(stdout); + } + + if (rc < 0 && errno == EAGAIN) { + printf("PASS: Unable to create a process with a pid that is " + "in use\n"); + exit(0); + } else { + printf("ERROR: "); + return rc; + } +} + +int main() +{ + int rc, pid, status; + unsigned long flags; + int nr_pids = 1; + + flags = SIGCHLD|CLONE_PARENT_SETTID|CLONE_CHILD_SETTID; + flags = SIGCHLD; + + /* + * Try to create a process with same pid as parent ! + */ + pids_list[0] = pids_list[1] = getpid(); + + pid = myclone(do_child, (void *)CHILD_ARG, flags, nr_pids, pids_list); + + if (verbose) { + printf("[%d, %d]: Parent waiting for %d\n", getpid(), + gettid(), pid); + } + + rc = waitpid(pid, &status, __WALL); + if (rc < 0) { + printf("ERROR: "); + verbose = 1; + } + + if (verbose) { + printf("\twaitpid(): child %d, rc %d, error %d, status 0x%x\n", + getpid(), rc, errno, status); + if (rc >=0) { + if (WIFEXITED(status)) { + printf("\t EXITED, %d\n", WEXITSTATUS(status)); + } else if (WIFSIGNALED(status)) { + printf("\t SIGNALED, %d\n", WTERMSIG(status)); + } + } + } + return 0; +} -- 1.6.6.1 _______________________________________________ Containers mailing list [email protected] https://lists.linux-foundation.org/mailman/listinfo/containers _______________________________________________ Devel mailing list [email protected] https://openvz.org/mailman/listinfo/devel
