From 973170e66726672518eb935eb0dc0e63876d133d Mon Sep 17 00:00:00 2001 From: Wang Nan Date: Tue, 8 Dec 2015 02:25:29 +0000 Subject: tools lib bpf: Check return value of strdup when reading map names Commit 561bbccac72d08babafaa33fd7fa9100ec4c9fb6 ("tools lib bpf: Extract and collect map names from BPF object file") forgets checking return value of strdup(). This patch fixes it. It also checks names pointer before strcmp() for safety. Signed-off-by: Wang Nan Acked-by: Namhyung Kim Cc: Zefan Li Cc: pi3orama@163.com Fixes: 561bbccac72d ("tools lib bpf: Extract and collect map names from BPF object file") Link: http://lkml.kernel.org/r/1449541544-67621-2-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/lib/bpf/libbpf.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) (limited to 'tools/lib/bpf/libbpf.c') diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index a298614ad091..16485ab05fc1 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -527,14 +527,14 @@ bpf_object__init_maps(struct bpf_object *obj, void *data, return 0; } -static void +static int bpf_object__init_maps_name(struct bpf_object *obj, int maps_shndx) { int i; Elf_Data *symbols = obj->efile.symbols; if (!symbols || maps_shndx < 0) - return; + return -EINVAL; for (i = 0; i < symbols->d_size / sizeof(GElf_Sym); i++) { GElf_Sym sym; @@ -556,9 +556,14 @@ bpf_object__init_maps_name(struct bpf_object *obj, int maps_shndx) continue; } obj->maps[map_idx].name = strdup(map_name); + if (!obj->maps[map_idx].name) { + pr_warning("failed to alloc map name\n"); + return -ENOMEM; + } pr_debug("map %zu is \"%s\"\n", map_idx, obj->maps[map_idx].name); } + return 0; } static int bpf_object__elf_collect(struct bpf_object *obj) @@ -663,7 +668,7 @@ static int bpf_object__elf_collect(struct bpf_object *obj) } if (maps_shndx >= 0) - bpf_object__init_maps_name(obj, maps_shndx); + err = bpf_object__init_maps_name(obj, maps_shndx); out: return err; } @@ -1372,7 +1377,7 @@ bpf_object__get_map_by_name(struct bpf_object *obj, const char *name) struct bpf_map *pos; bpf_map__for_each(pos, obj) { - if (strcmp(pos->name, name) == 0) + if (pos->name && !strcmp(pos->name, name)) return pos; } return NULL; -- cgit v1.2.3-55-g7522