diff options
| -rw-r--r-- | tools/lib/bpf/libbpf.c | 10 | ||||
| -rw-r--r-- | tools/testing/selftests/bpf/progs/test_global_map_resize.c | 16 |
2 files changed, 23 insertions, 3 deletions
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index e9c641a2fb20..52e353368f58 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -597,7 +597,7 @@ struct extern_desc { int sym_idx; int btf_id; int sec_btf_id; - const char *name; + char *name; char *essent_name; bool is_set; bool is_weak; @@ -4259,7 +4259,9 @@ static int bpf_object__collect_externs(struct bpf_object *obj) return ext->btf_id; } t = btf__type_by_id(obj->btf, ext->btf_id); - ext->name = btf__name_by_offset(obj->btf, t->name_off); + ext->name = strdup(btf__name_by_offset(obj->btf, t->name_off)); + if (!ext->name) + return -ENOMEM; ext->sym_idx = i; ext->is_weak = ELF64_ST_BIND(sym->st_info) == STB_WEAK; @@ -9138,8 +9140,10 @@ void bpf_object__close(struct bpf_object *obj) zfree(&obj->btf_custom_path); zfree(&obj->kconfig); - for (i = 0; i < obj->nr_extern; i++) + for (i = 0; i < obj->nr_extern; i++) { + zfree(&obj->externs[i].name); zfree(&obj->externs[i].essent_name); + } zfree(&obj->externs); obj->nr_extern = 0; diff --git a/tools/testing/selftests/bpf/progs/test_global_map_resize.c b/tools/testing/selftests/bpf/progs/test_global_map_resize.c index a3f220ba7025..ee65bad0436d 100644 --- a/tools/testing/selftests/bpf/progs/test_global_map_resize.c +++ b/tools/testing/selftests/bpf/progs/test_global_map_resize.c @@ -32,6 +32,16 @@ int my_int_last SEC(".data.array_not_last"); int percpu_arr[1] SEC(".data.percpu_arr"); +/* at least one extern is included, to ensure that a specific + * regression is tested whereby resizing resulted in a free-after-use + * bug after type information is invalidated by the resize operation. + * + * There isn't a particularly good API to test for this specific condition, + * but by having externs for the resizing tests it will cover this path. + */ +extern int LINUX_KERNEL_VERSION __kconfig; +long version_sink; + SEC("tp/syscalls/sys_enter_getpid") int bss_array_sum(void *ctx) { @@ -44,6 +54,9 @@ int bss_array_sum(void *ctx) for (size_t i = 0; i < bss_array_len; ++i) sum += array[i]; + /* see above; ensure this is not optimized out */ + version_sink = LINUX_KERNEL_VERSION; + return 0; } @@ -59,6 +72,9 @@ int data_array_sum(void *ctx) for (size_t i = 0; i < data_array_len; ++i) sum += my_array[i]; + /* see above; ensure this is not optimized out */ + version_sink = LINUX_KERNEL_VERSION; + return 0; } |