| Message ID | 20200124201847.212528-1-andriin@fb.com |
|---|---|
| State | Accepted |
| Delegated to: | BPF Maintainers |
| Headers | show |
| Series | [bpf-next] libbpf: fix realloc usage in bpf_core_find_cands | expand |
On 1/24/20 12:18 PM, Andrii Nakryiko wrote: > Fix bug requesting invalid size of reallocated array when constructing CO-RE > relocation candidate list. This can cause problems if there are many potential > candidates and a very fine-grained memory allocator bucket sizes are used. > > Fixes: ddc7c3042614 ("libbpf: implement BPF CO-RE offset relocation algorithm") > Reported-by: William Smith <williampsmith@fb.com> > Signed-off-by: Andrii Nakryiko <andriin@fb.com> Acked-by: Yonghong Song <yhs@fb.com>
On 1/24/20 9:18 PM, Andrii Nakryiko wrote: > Fix bug requesting invalid size of reallocated array when constructing CO-RE > relocation candidate list. This can cause problems if there are many potential > candidates and a very fine-grained memory allocator bucket sizes are used. > > Fixes: ddc7c3042614 ("libbpf: implement BPF CO-RE offset relocation algorithm") > Reported-by: William Smith <williampsmith@fb.com> > Signed-off-by: Andrii Nakryiko <andriin@fb.com> Applied, thanks!
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index ae34b681ae82..b581cb52ee5c 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -3870,7 +3870,9 @@ static struct ids_vec *bpf_core_find_cands(const struct btf *local_btf, if (strncmp(local_name, targ_name, local_essent_len) == 0) { pr_debug("[%d] %s: found candidate [%d] %s\n", local_type_id, local_name, i, targ_name); - new_ids = realloc(cand_ids->data, cand_ids->len + 1); + new_ids = reallocarray(cand_ids->data, + cand_ids->len + 1, + sizeof(*cand_ids->data)); if (!new_ids) { err = -ENOMEM; goto err_out;
Fix bug requesting invalid size of reallocated array when constructing CO-RE relocation candidate list. This can cause problems if there are many potential candidates and a very fine-grained memory allocator bucket sizes are used. Fixes: ddc7c3042614 ("libbpf: implement BPF CO-RE offset relocation algorithm") Reported-by: William Smith <williampsmith@fb.com> Signed-off-by: Andrii Nakryiko <andriin@fb.com> --- tools/lib/bpf/libbpf.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)