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
--
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