diff options
author | Ian Rogers <irogers@google.com> | 2024-02-09 19:17:43 -0800 |
---|---|---|
committer | Namhyung Kim <namhyung@kernel.org> | 2024-02-12 12:35:33 -0800 |
commit | 107ef66cb054f8d54e336236a31631a8cc167c1f (patch) | |
tree | d3b67ab8a3a16e344c3b05d1023bd80a2fa144d0 /tools/perf/util/symbol.c | |
parent | perf maps: Get map before returning in maps__find (diff) | |
download | linux-107ef66cb054f8d54e336236a31631a8cc167c1f.tar.gz linux-107ef66cb054f8d54e336236a31631a8cc167c1f.tar.bz2 linux-107ef66cb054f8d54e336236a31631a8cc167c1f.zip |
perf maps: Get map before returning in maps__find_by_name
Finding a map is done under a lock, returning the map without a
reference count means it can be removed without notice and causing
uses after free. Grab a reference count to the map within the lock
region and return this. Fix up locations that need a map__put
following this. Also fix some reference counted pointer comparisons.
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: K Prateek Nayak <kprateek.nayak@amd.com>
Cc: James Clark <james.clark@arm.com>
Cc: Vincent Whitchurch <vincent.whitchurch@axis.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Colin Ian King <colin.i.king@gmail.com>
Cc: Changbin Du <changbin.du@huawei.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Song Liu <song@kernel.org>
Cc: Leo Yan <leo.yan@linux.dev>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Artem Savkov <asavkov@redhat.com>
Cc: bpf@vger.kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240210031746.4057262-4-irogers@google.com
Diffstat (limited to 'tools/perf/util/symbol.c')
-rw-r--r-- | tools/perf/util/symbol.c | 18 |
1 files changed, 11 insertions, 7 deletions
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c index 1710b89e207c..0785a54e832e 100644 --- a/tools/perf/util/symbol.c +++ b/tools/perf/util/symbol.c @@ -814,7 +814,7 @@ static int maps__split_kallsyms(struct maps *kmaps, struct dso *dso, u64 delta, struct map *initial_map) { struct machine *machine; - struct map *curr_map = initial_map; + struct map *curr_map = map__get(initial_map); struct symbol *pos; int count = 0, moved = 0; struct rb_root_cached *root = &dso->symbols; @@ -858,13 +858,14 @@ static int maps__split_kallsyms(struct maps *kmaps, struct dso *dso, u64 delta, dso__set_loaded(curr_map_dso); } + map__zput(curr_map); curr_map = maps__find_by_name(kmaps, module); if (curr_map == NULL) { pr_debug("%s/proc/{kallsyms,modules} " "inconsistency while looking " "for \"%s\" module!\n", machine->root_dir, module); - curr_map = initial_map; + curr_map = map__get(initial_map); goto discard_symbol; } curr_map_dso = map__dso(curr_map); @@ -888,7 +889,7 @@ static int maps__split_kallsyms(struct maps *kmaps, struct dso *dso, u64 delta, * symbols at this point. */ goto discard_symbol; - } else if (curr_map != initial_map) { + } else if (!RC_CHK_EQUAL(curr_map, initial_map)) { char dso_name[PATH_MAX]; struct dso *ndso; @@ -899,7 +900,8 @@ static int maps__split_kallsyms(struct maps *kmaps, struct dso *dso, u64 delta, } if (count == 0) { - curr_map = initial_map; + map__zput(curr_map); + curr_map = map__get(initial_map); goto add_symbol; } @@ -913,6 +915,7 @@ static int maps__split_kallsyms(struct maps *kmaps, struct dso *dso, u64 delta, kernel_range++); ndso = dso__new(dso_name); + map__zput(curr_map); if (ndso == NULL) return -1; @@ -926,6 +929,7 @@ static int maps__split_kallsyms(struct maps *kmaps, struct dso *dso, u64 delta, map__set_mapping_type(curr_map, MAPPING_TYPE__IDENTITY); if (maps__insert(kmaps, curr_map)) { + map__zput(curr_map); dso__put(ndso); return -1; } @@ -936,7 +940,7 @@ static int maps__split_kallsyms(struct maps *kmaps, struct dso *dso, u64 delta, pos->end -= delta; } add_symbol: - if (curr_map != initial_map) { + if (!RC_CHK_EQUAL(curr_map, initial_map)) { struct dso *curr_map_dso = map__dso(curr_map); rb_erase_cached(&pos->rb_node, root); @@ -951,12 +955,12 @@ discard_symbol: symbol__delete(pos); } - if (curr_map != initial_map && + if (!RC_CHK_EQUAL(curr_map, initial_map) && dso->kernel == DSO_SPACE__KERNEL_GUEST && machine__is_default_guest(maps__machine(kmaps))) { dso__set_loaded(map__dso(curr_map)); } - + map__put(curr_map); return count + moved; } |