Implement virProcessRunInMountNamespace, which runs callback of type virProcessNamespaceCallback in a container namespace. Hope it'll nail it this time. --- src/libvirt_private.syms | 1 + src/util/virprocess.c | 63 ++++++++++++++++++++++++++++++++++++++++++++++ src/util/virprocess.h | 6 +++++ 3 files changed, 70 insertions(+) diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms index 2dbb8f8..e210fd0 100644 --- a/src/libvirt_private.syms +++ b/src/libvirt_private.syms @@ -1646,6 +1646,7 @@ virProcessGetNamespaces; virProcessGetStartTime; virProcessKill; virProcessKillPainfully; +virProcessRunInMountNamespace; virProcessSetAffinity; virProcessSetMaxFiles; virProcessSetMaxMemLock; diff --git a/src/util/virprocess.c b/src/util/virprocess.c index 9fc3207..7bb494e 100644 --- a/src/util/virprocess.c +++ b/src/util/virprocess.c @@ -31,6 +31,7 @@ # include <sys/resource.h> #endif #include <sched.h> +#include <stdlib.h> #ifdef __FreeBSD__ # include <sys/param.h> @@ -847,3 +848,65 @@ int virProcessGetStartTime(pid_t pid, return 0; } #endif + +#ifdef HAVE_SETNS +int virProcessRunInMountNamespace(pid_t pid, + virProcessNamespaceCallback cb, + void *opaque) +{ + char* path = NULL; + int ret = -1; + int cpid = -1; + int status = -1; + int fd = -1; + + if (virAsprintf(&path, "/proc/%llu/ns/mnt", + (unsigned long long)pid) < 0) { + goto cleanup; + } + + if ((fd = open(path, O_RDONLY)) < 0) { + virReportSystemError(errno, "%s", + _("Kernel does not provide mount namespace")); + goto cleanup; + } + + switch (cpid = fork()) { + case 0: + if (setns(fd, 0) == -1) { + _exit(-1); + } + + ret = cb(pid, opaque); + _exit(ret); + break; + case -1: + virReportSystemError(VIR_ERR_INTERNAL_ERROR, "%s", + _("Fork failed")); + goto cleanup; + default: + if (virProcessWait(cpid, &status) < 0 || status < 0) { + virReportSystemError(errno, + _("Callback failed with status %i"), + status); + ret = 1; + } else { + ret = 0; + } + } + +cleanup: + VIR_FREE(path); + VIR_FORCE_CLOSE(fd); + return ret; +} +#else +int virProcessRunInMountNamespace(pid_t pid ATTRIBUTE_UNUSED, + virProcessNamespaceCallback cb ATTRIBUTE_UNUSED, + void *opaque ATTRIBUTE_UNUSED) +{ + virReportSystemError(ENOSYS, "%s", + _("Mount namespaces are not available on this platform")); + return -1; +} +#endif diff --git a/src/util/virprocess.h b/src/util/virprocess.h index 9f77bc5..205abf7 100644 --- a/src/util/virprocess.h +++ b/src/util/virprocess.h @@ -60,4 +60,10 @@ int virProcessSetNamespaces(size_t nfdlist, int virProcessSetMaxMemLock(pid_t pid, unsigned long long bytes); int virProcessSetMaxProcesses(pid_t pid, unsigned int procs); int virProcessSetMaxFiles(pid_t pid, unsigned int files); + +typedef int (*virProcessNamespaceCallback)(pid_t pid, void *opaque); + +int virProcessRunInMountNamespace(pid_t pid, + virProcessNamespaceCallback cb, + void *opaque); #endif /* __VIR_PROCESS_H__ */