From: Daniel Hokka Zakrisson Date: Sat, 1 Mar 2008 00:26:31 +0000 (+0000) Subject: Revert commit 2690, clone is needed for pid namespaces and on kernels <2.6.16. X-Git-Tag: release-0.30.215~14 X-Git-Url: http://git.linux-vserver.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=4dd2d44ee45230e79b4797f162cdbbf767cad41c;p=util-vserver.git Revert commit 2690, clone is needed for pid namespaces and on kernels <2.6.16. git-svn-id: http://svn.linux-vserver.org/svn/util-vserver/trunk@2693 94cd875c-1c1d-0410-91d2-eb244daf1a30 --- diff --git a/src/rpm-fake.c b/src/rpm-fake.c index c751dc8..26c5fa8 100644 --- a/src/rpm-fake.c +++ b/src/rpm-fake.c @@ -25,7 +25,7 @@ #include #include -#include +#include #include #include @@ -49,7 +49,7 @@ #include #include #include -#include + // from selinux.h // FIXME: add configure autodetection and include directly @@ -629,12 +629,20 @@ execvWorker(char const *path, char * const argv[], char * const envp[]) return res; } +struct ExecvParams +{ + char const * path; + char * const * argv; + char * const * envp; + char const * mnts; +}; + static int -removeNamespaceMounts(char const *mnts) +removeNamespaceMountsChild(struct ExecvParams const *params) { - char buf[strlen(mnts)+1], *ptr; + char buf[strlen(params->mnts)+1], *ptr; - strcpy(buf, mnts); + strcpy(buf, params->mnts); ptr = strtok(buf, ":"); while (ptr) { if (umount2(ptr, 0)==-1) { @@ -648,28 +656,54 @@ removeNamespaceMounts(char const *mnts) ptr = strtok(0, ":"); } - return 0; + return execvWorker(params->path, params->argv, params->envp); } static int -execv_main(char const *path, char * const argv[], char * const envp[]) +removeNamespaceMounts(char const *path, + char * const argv[], char * const envp[]) { - int rc = 0; + if (mnts==0) return execvWorker(path, argv, envp); - if (sys_unshare(CLONE_NEWNS)==-1) { - perror("unshare()"); - return -1; - } + { + int status; + pid_t p, pid; + struct ExecvParams params; - if (mnts) - rc = removeNamespaceMounts(mnts); + params.path = path; + params.argv = argv; + params.envp = envp; + params.mnts = mnts; - if (rc!=0) - return rc; - - return execvWorker(path, argv, envp); + // the rpmlib signal-handler is still active; use the default one to + // make wait4() working... + signal(SIGCHLD, SIG_DFL); + +#ifdef NDEBUG + pid = sys_clone(CLONE_NEWNS|SIGCHLD|CLONE_VFORK, 0); +#else + pid = sys_clone(CLONE_NEWNS|SIGCHLD, 0); +#endif + + switch (pid) { + case -1 : return -1; + case 0 : _exit(removeNamespaceMountsChild(¶ms)); + default : break; + } + + while ((p=wait4(pid, &status, 0,0))==-1 && + (errno==EINTR || errno==EAGAIN)) ; + + if (p==-1) return -1; + + if (WIFEXITED(status)) _exit(WEXITSTATUS(status)); + if (WIFSIGNALED(status)) kill(getpid(), WTERMSIG(status)); + + return -1; + } } + int execv(char const *path, char * const argv[]) { @@ -681,7 +715,7 @@ execv(char const *path, char * const argv[]) WRITE_MSG(2, "', ...)\n"); } - return execv_main(path, argv, environ); + return removeNamespaceMounts(path, argv, environ); } int @@ -695,7 +729,7 @@ rpm_execcon(unsigned int UNUSED verified, WRITE_MSG(2, "', ...)\n"); } - return execv_main(filename, argv, envp); + return removeNamespaceMounts(filename, argv, envp); } int diff --git a/src/vnamespace.c b/src/vnamespace.c index 076b4e4..c71cc9f 100644 --- a/src/vnamespace.c +++ b/src/vnamespace.c @@ -21,7 +21,7 @@ #endif #include "util.h" -#include +#include #include @@ -88,14 +88,26 @@ showVersion() } static void -newNamespace(void) +newNamespace(char const *cmd) { - int rc; + pid_t pid; - rc = sys_unshare(CLONE_NEWNS); - if (rc!=0) { - perror("vnamespace: unshare()"); - exit(wrapper_exit_code); + signal(SIGCHLD, SIG_DFL); + +#ifdef NDEBUG + pid = sys_clone(CLONE_NEWNS|CLONE_VFORK|SIGCHLD, 0); +#else + pid = sys_clone(CLONE_NEWNS|SIGCHLD, 0); +#endif + + switch (pid) { + case -1 : + perror("vnamespace: clone()"); + exit(wrapper_exit_code); + case 0 : + break; + default : + exitLikeProcess(pid, cmd, wrapper_exit_code); } } @@ -169,7 +181,7 @@ int main(int argc, char *argv[]) else if (optind==argc && (do_new || do_enter)) WRITE_MSG(2, "No command specified; try '--help' for more information\n"); else { - if (do_new) newNamespace(); + if (do_new) newNamespace(argv[optind]); else if (do_set) setNamespace(VC_SAMECTX, CLONE_NEWNS|CLONE_FS); else if (do_cleanup) cleanupNamespace(); else if (do_enter) enterNamespace(xid, CLONE_NEWNS|CLONE_FS); diff --git a/src/vspace.c b/src/vspace.c index 4819138..4c1c64f 100644 --- a/src/vspace.c +++ b/src/vspace.c @@ -22,7 +22,7 @@ #endif #include "util.h" -#include +#include #include @@ -106,14 +106,30 @@ showVersion() } static void -newSpaces(uint_least64_t mask) +newSpaces(uint_least64_t mask, const char *cmd) { - int rc; + pid_t pid; - rc = sys_unshare(mask); - if (rc) { - perror(ENSC_WRAPPERS_PREFIX "unshare()"); - exit(wrapper_exit_code); + /* optimize default case */ + if (mask == 0) + return; + + signal(SIGCHLD, SIG_DFL); + +#ifdef NDEBUG + pid = sys_clone((int) mask | CLONE_VFORK|SIGCHLD, 0); +#else + pid = sys_clone((int) mask | SIGCHLD, 0); +#endif + + switch (pid) { + case -1 : + perror(ENSC_WRAPPERS_PREFIX "clone()"); + exit(wrapper_exit_code); + case 0 : + break; + default : + exitLikeProcess(pid, cmd, wrapper_exit_code); } } @@ -195,7 +211,7 @@ int main(int argc, char *argv[]) else if (optind==argc && (do_new || do_enter)) WRITE_MSG(2, "No command specified; try '--help' for more information\n"); else { - if (do_new) newSpaces(mask); + if (do_new) newSpaces(mask, argv[optind]); else if (do_set) setSpaces(VC_SAMECTX, mask); else if (do_enter) enterSpaces(xid, mask);