On Fri, Mar 26, 2021 at 9:35 PM Andrii Nakryiko <andrii@xxxxxxxxxx> wrote:
>
> Free temporary allocated memory used to construct finalized .BTF.ext data.
> Found by Coverity static analysis on libbpf's Github repo.
>
> Fixes: 8fd27bf69b86 ("libbpf: Add BPF static linker BTF and BTF.ext support")
> Signed-off-by: Andrii Nakryiko <andrii@xxxxxxxxxx>
Acked-by: Song Liu <songliubraving@xxxxxx>
> ---
> tools/lib/bpf/linker.c | 24 ++++++++++++++++--------
> 1 file changed, 16 insertions(+), 8 deletions(-)
>
> diff --git a/tools/lib/bpf/linker.c b/tools/lib/bpf/linker.c
> index a29d62ff8041..46b16cbdcda3 100644
> --- a/tools/lib/bpf/linker.c
> +++ b/tools/lib/bpf/linker.c
> @@ -1906,8 +1906,10 @@ static int finalize_btf_ext(struct bpf_linker *linker)
> struct dst_sec *sec = &linker->secs[i];
>
> sz = emit_btf_ext_data(linker, cur, sec->sec_name, &sec->func_info);
> - if (sz < 0)
> - return sz;
> + if (sz < 0) {
> + err = sz;
> + goto out;
> + }
>
> cur += sz;
> }
> @@ -1921,8 +1923,10 @@ static int finalize_btf_ext(struct bpf_linker *linker)
> struct dst_sec *sec = &linker->secs[i];
>
> sz = emit_btf_ext_data(linker, cur, sec->sec_name, &sec->line_info);
> - if (sz < 0)
> - return sz;
> + if (sz < 0) {
> + err = sz;
> + goto out;
> + }
>
> cur += sz;
> }
> @@ -1936,8 +1940,10 @@ static int finalize_btf_ext(struct bpf_linker *linker)
> struct dst_sec *sec = &linker->secs[i];
>
> sz = emit_btf_ext_data(linker, cur, sec->sec_name, &sec->core_relo_info);
> - if (sz < 0)
> - return sz;
> + if (sz < 0) {
> + err = sz;
> + goto out;
> + }
>
> cur += sz;
> }
> @@ -1948,8 +1954,10 @@ static int finalize_btf_ext(struct bpf_linker *linker)
> if (err) {
> linker->btf_ext = NULL;
> pr_warn("failed to parse final .BTF.ext data: %d\n", err);
> - return err;
> + goto out;
> }
>
> - return 0;
> +out:
> + free(data);
> + return err;
> }
> --
> 2.30.2
>
