To prevent futher commits calling machine__delete() on non-allocated 'struct machine' (which would cause memory corruption), this patch enforces machine__init(), record whether a machine structure is dynamically allocated or not, and warn if machine__delete() is called on incorrect object.
Signed-off-by: Wang Nan <wangn...@huawei.com> Cc: Arnaldo Carvalho de Melo <a...@redhat.com> Cc: Jiri Olsa <jo...@kernel.org> Cc: Masami Hiramatsu <masami.hiramatsu...@hitachi.com> Cc: Namhyung Kim <namhy...@kernel.org> --- tools/perf/tests/vmlinux-kallsyms.c | 4 ++-- tools/perf/util/machine.c | 14 +++++++++----- tools/perf/util/machine.h | 3 ++- 3 files changed, 13 insertions(+), 8 deletions(-) diff --git a/tools/perf/tests/vmlinux-kallsyms.c b/tools/perf/tests/vmlinux-kallsyms.c index f0bfc9e..441e93d 100644 --- a/tools/perf/tests/vmlinux-kallsyms.c +++ b/tools/perf/tests/vmlinux-kallsyms.c @@ -35,8 +35,8 @@ int test__vmlinux_matches_kallsyms(int subtest __maybe_unused) * Init the machines that will hold kernel, modules obtained from * both vmlinux + .ko files and from /proc/kallsyms split by modules. */ - machine__init(&kallsyms, "", HOST_KERNEL_ID); - machine__init(&vmlinux, "", HOST_KERNEL_ID); + machine__init(&kallsyms, "", HOST_KERNEL_ID, false); + machine__init(&vmlinux, "", HOST_KERNEL_ID, false); /* * Step 2: diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c index f5882b8..a2b9b47 100644 --- a/tools/perf/util/machine.c +++ b/tools/perf/util/machine.c @@ -23,7 +23,7 @@ static void dsos__init(struct dsos *dsos) pthread_rwlock_init(&dsos->lock, NULL); } -int machine__init(struct machine *machine, const char *root_dir, pid_t pid) +int machine__init(struct machine *machine, const char *root_dir, pid_t pid, bool allocated) { map_groups__init(&machine->kmaps, machine); RB_CLEAR_NODE(&machine->rb_node); @@ -64,6 +64,7 @@ int machine__init(struct machine *machine, const char *root_dir, pid_t pid) } machine->current_tid = NULL; + machine->allocated = allocated; return 0; } @@ -73,7 +74,7 @@ struct machine *machine__new_host(void) struct machine *machine = malloc(sizeof(*machine)); if (machine != NULL) { - machine__init(machine, "", HOST_KERNEL_ID); + machine__init(machine, "", HOST_KERNEL_ID, true); if (machine__create_kernel_maps(machine) < 0) goto out_delete; @@ -136,12 +137,15 @@ void machine__exit(struct machine *machine) void machine__delete(struct machine *machine) { machine__exit(machine); - free(machine); + if (!machine->allocated) + free(machine); + else + pr_warning("WARNING: delete a non-allocated machine. Skip.\n"); } void machines__init(struct machines *machines) { - machine__init(&machines->host, "", HOST_KERNEL_ID); + machine__init(&machines->host, "", HOST_KERNEL_ID, false); machines->guests = RB_ROOT; machines->symbol_filter = NULL; } @@ -162,7 +166,7 @@ struct machine *machines__add(struct machines *machines, pid_t pid, if (machine == NULL) return NULL; - if (machine__init(machine, root_dir, pid) != 0) { + if (machine__init(machine, root_dir, pid, true) != 0) { free(machine); return NULL; } diff --git a/tools/perf/util/machine.h b/tools/perf/util/machine.h index 2c2b443..24dfd46 100644 --- a/tools/perf/util/machine.h +++ b/tools/perf/util/machine.h @@ -28,6 +28,7 @@ struct machine { pid_t pid; u16 id_hdr_size; bool comm_exec; + bool allocated; char *root_dir; struct rb_root threads; pthread_rwlock_t threads_lock; @@ -131,7 +132,7 @@ void machines__set_symbol_filter(struct machines *machines, void machines__set_comm_exec(struct machines *machines, bool comm_exec); struct machine *machine__new_host(void); -int machine__init(struct machine *machine, const char *root_dir, pid_t pid); +int machine__init(struct machine *machine, const char *root_dir, pid_t pid, bool allocated); void machine__exit(struct machine *machine); void machine__delete_threads(struct machine *machine); void machine__delete(struct machine *machine); -- 1.8.3.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/