Something went wrong. Try again.
(I'm so sorry!) Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel os linux
Something went wrong. Try again.
123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381// SPDX-License-Identifier: GPL-2.0-only/* * * Copyright (C) 2017 Hari Bathini, IBM Corporation */
#include "namespaces.h"#include "event.h"#include <sys/types.h>#include <sys/stat.h>#include <fcntl.h>#include <limits.h>#include <sched.h>#include <stdlib.h>#include <stdio.h>#include <string.h>#include <unistd.h>#include <asm/bug.h>#include <linux/kernel.h>#include <linux/zalloc.h>
static const char *perf_ns__names[] = { [NET_NS_INDEX] = "net", [UTS_NS_INDEX] = "uts", [IPC_NS_INDEX] = "ipc", [PID_NS_INDEX] = "pid", [USER_NS_INDEX] = "user", [MNT_NS_INDEX] = "mnt", [CGROUP_NS_INDEX] = "cgroup",};
const char *perf_ns__name(unsigned int id){ if (id >= ARRAY_SIZE(perf_ns__names)) return "UNKNOWN"; return perf_ns__names[id];}
struct namespaces *namespaces__new(struct perf_record_namespaces *event){ struct namespaces *namespaces; u64 link_info_size = ((event ? event->nr_namespaces : NR_NAMESPACES) * sizeof(struct perf_ns_link_info));
namespaces = zalloc(sizeof(struct namespaces) + link_info_size); if (!namespaces) return NULL;
namespaces->end_time = -1;
if (event) memcpy(namespaces->link_info, event->link_info, link_info_size);
return namespaces;}
void namespaces__free(struct namespaces *namespaces){ free(namespaces);}
static int nsinfo__get_nspid(pid_t *tgid, pid_t *nstgid, bool *in_pidns, const char *path){ FILE *f = NULL; char *statln = NULL; size_t linesz = 0; char *nspid;
f = fopen(path, "r"); if (f == NULL) return -1;
while (getline(&statln, &linesz, f) != -1) { /* Use tgid if CONFIG_PID_NS is not defined. */ if (strstr(statln, "Tgid:") != NULL) { *tgid = (pid_t)strtol(strrchr(statln, '\t'), NULL, 10); *nstgid = *tgid; }
if (strstr(statln, "NStgid:") != NULL) { nspid = strrchr(statln, '\t'); *nstgid = (pid_t)strtol(nspid, NULL, 10); /* * If innermost tgid is not the first, process is in a different * PID namespace. */ *in_pidns = (statln + sizeof("NStgid:") - 1) != nspid; break; } }
fclose(f); free(statln); return 0;}
int nsinfo__init(struct nsinfo *nsi){ char oldns[PATH_MAX]; char spath[PATH_MAX]; char *newns = NULL; struct stat old_stat; struct stat new_stat; int rv = -1;
if (snprintf(oldns, PATH_MAX, "/proc/self/ns/mnt") >= PATH_MAX) return rv;
if (asprintf(&newns, "/proc/%d/ns/mnt", nsinfo__pid(nsi)) == -1) return rv;
if (stat(oldns, &old_stat) < 0) goto out;
if (stat(newns, &new_stat) < 0) goto out;
/* Check if the mount namespaces differ, if so then indicate that we * want to switch as part of looking up dso/map data. */ if (old_stat.st_ino != new_stat.st_ino) { RC_CHK_ACCESS(nsi)->need_setns = true; RC_CHK_ACCESS(nsi)->mntns_path = newns; newns = NULL; }
/* If we're dealing with a process that is in a different PID namespace, * attempt to work out the innermost tgid for the process. */ if (snprintf(spath, PATH_MAX, "/proc/%d/status", nsinfo__pid(nsi)) >= PATH_MAX) goto out;
rv = nsinfo__get_nspid(&RC_CHK_ACCESS(nsi)->tgid, &RC_CHK_ACCESS(nsi)->nstgid, &RC_CHK_ACCESS(nsi)->in_pidns, spath);
out: free(newns); return rv;}
static struct nsinfo *nsinfo__alloc(void){ struct nsinfo *res; RC_STRUCT(nsinfo) *nsi;
nsi = calloc(1, sizeof(*nsi)); if (ADD_RC_CHK(res, nsi)) refcount_set(&nsi->refcnt, 1);
return res;}
struct nsinfo *nsinfo__new(pid_t pid){ struct nsinfo *nsi;
if (pid == 0) return NULL;
nsi = nsinfo__alloc(); if (!nsi) return NULL;
RC_CHK_ACCESS(nsi)->pid = pid; RC_CHK_ACCESS(nsi)->tgid = pid; RC_CHK_ACCESS(nsi)->nstgid = pid; nsinfo__clear_need_setns(nsi); RC_CHK_ACCESS(nsi)->in_pidns = false; /* Init may fail if the process exits while we're trying to look at its * proc information. In that case, save the pid but don't try to enter * the namespace. */ if (nsinfo__init(nsi) == -1) nsinfo__clear_need_setns(nsi);
return nsi;}
static const char *nsinfo__mntns_path(const struct nsinfo *nsi){ return RC_CHK_ACCESS(nsi)->mntns_path;}
struct nsinfo *nsinfo__copy(const struct nsinfo *nsi){ struct nsinfo *nnsi;
if (nsi == NULL) return NULL;
nnsi = nsinfo__alloc(); if (!nnsi) return NULL;
RC_CHK_ACCESS(nnsi)->pid = nsinfo__pid(nsi); RC_CHK_ACCESS(nnsi)->tgid = nsinfo__tgid(nsi); RC_CHK_ACCESS(nnsi)->nstgid = nsinfo__nstgid(nsi); RC_CHK_ACCESS(nnsi)->need_setns = nsinfo__need_setns(nsi); RC_CHK_ACCESS(nnsi)->in_pidns = nsinfo__in_pidns(nsi); if (nsinfo__mntns_path(nsi)) { RC_CHK_ACCESS(nnsi)->mntns_path = strdup(nsinfo__mntns_path(nsi)); if (!RC_CHK_ACCESS(nnsi)->mntns_path) { nsinfo__put(nnsi); return NULL; } }
return nnsi;}
static refcount_t *nsinfo__refcnt(struct nsinfo *nsi){ return &RC_CHK_ACCESS(nsi)->refcnt;}
static void nsinfo__delete(struct nsinfo *nsi){ if (nsi) { WARN_ONCE(refcount_read(nsinfo__refcnt(nsi)) != 0, "nsinfo refcnt unbalanced\n"); zfree(&RC_CHK_ACCESS(nsi)->mntns_path); RC_CHK_FREE(nsi); }}
struct nsinfo *nsinfo__get(struct nsinfo *nsi){ struct nsinfo *result;
if (RC_CHK_GET(result, nsi)) refcount_inc(nsinfo__refcnt(nsi));
return result;}
void nsinfo__put(struct nsinfo *nsi){ if (nsi && refcount_dec_and_test(nsinfo__refcnt(nsi))) nsinfo__delete(nsi); else RC_CHK_PUT(nsi);}
bool nsinfo__need_setns(const struct nsinfo *nsi){ return RC_CHK_ACCESS(nsi)->need_setns;}
void nsinfo__clear_need_setns(struct nsinfo *nsi){ RC_CHK_ACCESS(nsi)->need_setns = false;}
pid_t nsinfo__tgid(const struct nsinfo *nsi){ return RC_CHK_ACCESS(nsi)->tgid;}
pid_t nsinfo__nstgid(const struct nsinfo *nsi){ return RC_CHK_ACCESS(nsi)->nstgid;}
pid_t nsinfo__pid(const struct nsinfo *nsi){ return RC_CHK_ACCESS(nsi)->pid;}
bool nsinfo__in_pidns(const struct nsinfo *nsi){ return RC_CHK_ACCESS(nsi)->in_pidns;}
void nsinfo__set_in_pidns(struct nsinfo *nsi){ RC_CHK_ACCESS(nsi)->in_pidns = true;}
void nsinfo__mountns_enter(struct nsinfo *nsi, struct nscookie *nc){ char curpath[PATH_MAX]; int oldns = -1; int newns = -1; char *oldcwd = NULL;
if (nc == NULL) return;
nc->oldns = -1; nc->newns = -1;
if (!nsi || !nsinfo__need_setns(nsi)) return;
if (!getcwd(curpath, sizeof(curpath))) return;
oldcwd = strdup(curpath); if (!oldcwd) return;
oldns = open("/proc/self/ns/mnt", O_RDONLY); if (oldns < 0) goto errout;
newns = open(nsinfo__mntns_path(nsi), O_RDONLY); if (newns < 0) goto errout;
if (setns(newns, CLONE_NEWNS) < 0) goto errout;
nc->oldcwd = oldcwd; nc->oldns = oldns; nc->newns = newns; return;
errout: free(oldcwd); if (oldns > -1) close(oldns); if (newns > -1) close(newns);}
void nsinfo__mountns_exit(struct nscookie *nc){ if (nc == NULL || nc->oldns == -1 || nc->newns == -1 || !nc->oldcwd) return;
setns(nc->oldns, CLONE_NEWNS);
if (nc->oldcwd) { WARN_ON_ONCE(chdir(nc->oldcwd)); zfree(&nc->oldcwd); }
if (nc->oldns > -1) { close(nc->oldns); nc->oldns = -1; }
if (nc->newns > -1) { close(nc->newns); nc->newns = -1; }}
char *nsinfo__realpath(const char *path, struct nsinfo *nsi){ char *rpath; struct nscookie nsc;
nsinfo__mountns_enter(nsi, &nsc); rpath = realpath(path, NULL); nsinfo__mountns_exit(&nsc);
return rpath;}
int nsinfo__stat(const char *filename, struct stat *st, struct nsinfo *nsi){ int ret; struct nscookie nsc;
nsinfo__mountns_enter(nsi, &nsc); ret = stat(filename, st); nsinfo__mountns_exit(&nsc);
return ret;}
bool nsinfo__is_in_root_namespace(void){ pid_t tgid = 0, nstgid = 0; bool in_pidns = false;
nsinfo__get_nspid(&tgid, &nstgid, &in_pidns, "/proc/self/status"); return !in_pidns;}