There may be threads racing to update dso->nsinfo: https://lore.kernel.org/linux-perf-users/CAP-5=fWZH20L4kv-BwVtGLwR=Em3AOOT+Q4QGivvQuYn5AsPRg@xxxxxxxxxxxxxx/ Holding the dso->lock avoids use-after-free, memory leaks and other such bugs. Apply the fix in: https://lore.kernel.org/linux-perf-users/20211118193714.2293728-1-irogers@xxxxxxxxxx/ of there being a missing nsinfo__put now that the accesses are data race free. Fixes test "Lookup mmap thread" when compiled with address sanitizer. Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx> --- tools/perf/builtin-inject.c | 4 ++++ tools/perf/util/annotate.c | 2 ++ tools/perf/util/build-id.c | 12 +++++++++--- tools/perf/util/dso.c | 7 ++++++- tools/perf/util/map.c | 3 +++ tools/perf/util/probe-event.c | 3 +++ tools/perf/util/symbol.c | 2 +- 7 files changed, 28 insertions(+), 5 deletions(-) diff --git a/tools/perf/builtin-inject.c b/tools/perf/builtin-inject.c index 2a0f992ca0be..2a914eaf6425 100644 --- a/tools/perf/builtin-inject.c +++ b/tools/perf/builtin-inject.c @@ -433,8 +433,10 @@ static struct dso *findnew_dso(int pid, int tid, const char *filename, } if (dso) { + mutex_lock(&dso->lock); nsinfo__put(dso->nsinfo); dso->nsinfo = nsi; + mutex_unlock(&dso->lock); } else nsinfo__put(nsi); @@ -617,6 +619,7 @@ static int dso__read_build_id(struct dso *dso) if (dso->has_build_id) return 0; + mutex_lock(&dso->lock); nsinfo__mountns_enter(dso->nsinfo, &nsc); if (filename__read_build_id(dso->long_name, &dso->bid) > 0) dso->has_build_id = true; @@ -630,6 +633,7 @@ static int dso__read_build_id(struct dso *dso) free(new_name); } nsinfo__mountns_exit(&nsc); + mutex_unlock(&dso->lock); return dso->has_build_id ? 0 : -1; } diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c index 29d804d76145..1bbfbc8e1554 100644 --- a/tools/perf/util/annotate.c +++ b/tools/perf/util/annotate.c @@ -1697,6 +1697,7 @@ static int dso__disassemble_filename(struct dso *dso, char *filename, size_t fil */ __symbol__join_symfs(filename, filename_size, dso->long_name); + mutex_lock(&dso->lock); if (access(filename, R_OK) && errno == ENOENT && dso->nsinfo) { char *new_name = filename_with_chroot(dso->nsinfo->pid, filename); @@ -1705,6 +1706,7 @@ static int dso__disassemble_filename(struct dso *dso, char *filename, size_t fil free(new_name); } } + mutex_unlock(&dso->lock); } free(build_id_path); diff --git a/tools/perf/util/build-id.c b/tools/perf/util/build-id.c index ec18ed5caf3e..a839b30c981b 100644 --- a/tools/perf/util/build-id.c +++ b/tools/perf/util/build-id.c @@ -898,11 +898,15 @@ static int filename__read_build_id_ns(const char *filename, static bool dso__build_id_mismatch(struct dso *dso, const char *name) { struct build_id bid; + bool ret = false; - if (filename__read_build_id_ns(name, &bid, dso->nsinfo) < 0) - return false; + mutex_lock(&dso->lock); + if (filename__read_build_id_ns(name, &bid, dso->nsinfo) >= 0) + ret = !dso__build_id_equal(dso, &bid); - return !dso__build_id_equal(dso, &bid); + mutex_unlock(&dso->lock); + + return ret; } static int dso__cache_build_id(struct dso *dso, struct machine *machine, @@ -941,8 +945,10 @@ static int dso__cache_build_id(struct dso *dso, struct machine *machine, if (!is_kallsyms && dso__build_id_mismatch(dso, name)) goto out_free; + mutex_lock(&dso->lock); ret = build_id_cache__add_b(&dso->bid, name, dso->nsinfo, is_kallsyms, is_vdso, proper_name, root_dir); + mutex_unlock(&dso->lock); out_free: free(allocated_name); return ret; diff --git a/tools/perf/util/dso.c b/tools/perf/util/dso.c index c7a5b42d1311..89e1b93cb874 100644 --- a/tools/perf/util/dso.c +++ b/tools/perf/util/dso.c @@ -501,6 +501,7 @@ static int __open_dso(struct dso *dso, struct machine *machine) if (!name) return -ENOMEM; + mutex_lock(&dso->lock); if (machine) root_dir = machine->root_dir; @@ -541,6 +542,7 @@ static int __open_dso(struct dso *dso, struct machine *machine) unlink(name); out: + mutex_unlock(&dso->lock); free(name); return fd; } @@ -559,8 +561,11 @@ static int open_dso(struct dso *dso, struct machine *machine) int fd; struct nscookie nsc; - if (dso->binary_type != DSO_BINARY_TYPE__BUILD_ID_CACHE) + if (dso->binary_type != DSO_BINARY_TYPE__BUILD_ID_CACHE) { + mutex_lock(&dso->lock); nsinfo__mountns_enter(dso->nsinfo, &nsc); + mutex_unlock(&dso->lock); + } fd = __open_dso(dso, machine); if (dso->binary_type != DSO_BINARY_TYPE__BUILD_ID_CACHE) nsinfo__mountns_exit(&nsc); diff --git a/tools/perf/util/map.c b/tools/perf/util/map.c index e0aa4a254583..f3a3d9b3a40d 100644 --- a/tools/perf/util/map.c +++ b/tools/perf/util/map.c @@ -181,7 +181,10 @@ struct map *map__new(struct machine *machine, u64 start, u64 len, if (!(prot & PROT_EXEC)) dso__set_loaded(dso); } + mutex_lock(&dso->lock); + nsinfo__put(dso->nsinfo); dso->nsinfo = nsi; + mutex_unlock(&dso->lock); if (build_id__is_defined(bid)) { dso__set_build_id(dso, bid); diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c index 785246ff4179..0c24bc7afbca 100644 --- a/tools/perf/util/probe-event.c +++ b/tools/perf/util/probe-event.c @@ -29,6 +29,7 @@ #include "color.h" #include "map.h" #include "maps.h" +#include "mutex.h" #include "symbol.h" #include <api/fs/fs.h> #include "trace-event.h" /* For __maybe_unused */ @@ -180,8 +181,10 @@ struct map *get_target_map(const char *target, struct nsinfo *nsi, bool user) map = dso__new_map(target); if (map && map->dso) { + mutex_lock(&map->dso->lock); nsinfo__put(map->dso->nsinfo); map->dso->nsinfo = nsinfo__get(nsi); + mutex_unlock(&map->dso->lock); } return map; } else { diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c index 656d9b4dd456..a3a165ae933a 100644 --- a/tools/perf/util/symbol.c +++ b/tools/perf/util/symbol.c @@ -1791,6 +1791,7 @@ int dso__load(struct dso *dso, struct map *map) char newmapname[PATH_MAX]; const char *map_path = dso->long_name; + mutex_lock(&dso->lock); perfmap = strncmp(dso->name, "/tmp/perf-", 10) == 0; if (perfmap) { if (dso->nsinfo && (dso__find_perf_map(newmapname, @@ -1800,7 +1801,6 @@ int dso__load(struct dso *dso, struct map *map) } nsinfo__mountns_enter(dso->nsinfo, &nsc); - mutex_lock(&dso->lock); /* check again under the dso->lock */ if (dso__loaded(dso)) { -- 2.37.2.609.g9ff673ca1a-goog
