Commit e54dea69 authored by Ian Rogers's avatar Ian Rogers Committed by Arnaldo Carvalho de Melo
Browse files

perf dso: Hold lock when accessing nsinfo 

There may be threads racing to update dso->nsinfo:

  https://lore.kernel.org/linux-perf-users/CAP-5=fWZH20L4kv-BwVtGLwR=Em3AOOT+Q4QGivvQuYn5AsPRg@mail.gmail.com/

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@google.com/



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: default avatarIan Rogers <irogers@google.com>
Reviewed-by: default avatarAdrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexandre Truong <alexandre.truong@arm.com>
Cc: Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andres Freund <andres@anarazel.de>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: André Almeida <andrealmeid@igalia.com>
Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com>
Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Cc: Colin Ian King <colin.king@intel.com>
Cc: Dario Petrillo <dario.pk1@gmail.com>
Cc: Darren Hart <dvhart@infradead.org>
Cc: Dave Marchevsky <davemarchevsky@fb.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Fangrui Song <maskray@google.com>
Cc: Hewenliang <hewenliang4@huawei.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jason Wang <wangborong@cdjrlc.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kim Phillips <kim.phillips@amd.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin Liška <mliska@suse.cz>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Pavithra Gurushankar <gpavithrasha@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Monnet <quentin@isovalent.com>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Remi Bernon <rbernon@codeweavers.com>
Cc: Riccardo Mancini <rickyman7@gmail.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Tom Rix <trix@redhat.com>
Cc: Weiguo Li <liwg06@foxmail.com>
Cc: Wenyu Liu <liuwenyu7@huawei.com>
Cc: William Cohen <wcohen@redhat.com>
Cc: Zechuan Chen <chenzechuan1@huawei.com>
Cc: bpf@vger.kernel.org
Cc: llvm@lists.linux.dev
Cc: yaowenbin <yaowenbin1@huawei.com>
Link: https://lore.kernel.org/r/20220826164242.43412-15-irogers@google.com


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent d8e40b58

tools/perf/builtin-inject.c

+4 −0
Original line number Diff line number Diff line
@@ -436,8 +436,10 @@ 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);
@@ -620,6 +622,7 @@ 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;
@@ -633,6 +636,7 @@ 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;

}

tools/perf/util/annotate.c

+2 −0
Original line number Diff line number Diff line
@@ -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);

tools/perf/util/build-id.c

+9 −3
Original line number Diff line number Diff line
@@ -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;

tools/perf/util/dso.c

+6 −1
Original line number Diff line number Diff line
@@ -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);

tools/perf/util/map.c

+3 −0
Original line number Diff line number Diff line
@@ -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);