perf kmaps: Check kmaps to make code more robust
This patch add checks in places where map__kmap is used to get kmaps
from struct kmap.
Error messages are added at map__kmap to warn invalid accessing of kmap
(for the case of !map->dso->kernel, kmap(map) does not exists at all).
Also, introduces map__kmaps() to warn uninitialized kmaps.
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: pi3orama@163.com
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Zefan Li <lizefan@huawei.com>
Link: http://lkml.kernel.org/r/1428394966-131044-2-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index fddeb90..201f6c4c 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -630,13 +630,16 @@
static int dso__split_kallsyms_for_kcore(struct dso *dso, struct map *map,
symbol_filter_t filter)
{
- struct map_groups *kmaps = map__kmap(map)->kmaps;
+ struct map_groups *kmaps = map__kmaps(map);
struct map *curr_map;
struct symbol *pos;
int count = 0, moved = 0;
struct rb_root *root = &dso->symbols[map->type];
struct rb_node *next = rb_first(root);
+ if (!kmaps)
+ return -1;
+
while (next) {
char *module;
@@ -682,8 +685,8 @@
static int dso__split_kallsyms(struct dso *dso, struct map *map, u64 delta,
symbol_filter_t filter)
{
- struct map_groups *kmaps = map__kmap(map)->kmaps;
- struct machine *machine = kmaps->machine;
+ struct map_groups *kmaps = map__kmaps(map);
+ struct machine *machine;
struct map *curr_map = map;
struct symbol *pos;
int count = 0, moved = 0;
@@ -691,6 +694,11 @@
struct rb_node *next = rb_first(root);
int kernel_range = 0;
+ if (!kmaps)
+ return -1;
+
+ machine = kmaps->machine;
+
while (next) {
char *module;
@@ -1025,9 +1033,12 @@
static int validate_kcore_modules(const char *kallsyms_filename,
struct map *map)
{
- struct map_groups *kmaps = map__kmap(map)->kmaps;
+ struct map_groups *kmaps = map__kmaps(map);
char modules_filename[PATH_MAX];
+ if (!kmaps)
+ return -EINVAL;
+
if (!filename_from_kallsyms_filename(modules_filename, "modules",
kallsyms_filename))
return -EINVAL;
@@ -1043,6 +1054,9 @@
{
struct kmap *kmap = map__kmap(map);
+ if (!kmap)
+ return -EINVAL;
+
if (kmap->ref_reloc_sym && kmap->ref_reloc_sym->name) {
u64 start;
@@ -1081,8 +1095,8 @@
static int dso__load_kcore(struct dso *dso, struct map *map,
const char *kallsyms_filename)
{
- struct map_groups *kmaps = map__kmap(map)->kmaps;
- struct machine *machine = kmaps->machine;
+ struct map_groups *kmaps = map__kmaps(map);
+ struct machine *machine;
struct kcore_mapfn_data md;
struct map *old_map, *new_map, *replacement_map = NULL;
bool is_64_bit;
@@ -1090,6 +1104,11 @@
char kcore_filename[PATH_MAX];
struct symbol *sym;
+ if (!kmaps)
+ return -EINVAL;
+
+ machine = kmaps->machine;
+
/* This function requires that the map is the kernel map */
if (map != machine->vmlinux_maps[map->type])
return -EINVAL;
@@ -1202,6 +1221,9 @@
struct kmap *kmap = map__kmap(map);
u64 addr;
+ if (!kmap)
+ return -1;
+
if (!kmap->ref_reloc_sym || !kmap->ref_reloc_sym->name)
return 0;