Commit ebbd7f64 authored by Quentin Monnet's avatar Quentin Monnet Committed by Andrii Nakryiko
Browse files

bpftool: Fix memory leak in prog_dump() 



Following the extraction of prog_dump() from do_dump(), the struct btf
allocated in prog_dump() is no longer freed on error; the struct
bpf_prog_linfo is not freed at all. Make sure we release them before
exiting the function.

Fixes: ec202509 ("bpftool: Match several programs with same tag")
Signed-off-by: default avatarQuentin Monnet <quentin@isovalent.com>
Signed-off-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211110114632.24537-2-quentin@isovalent.com
parent 325d956d

tools/bpf/bpftool/prog.c

+9 −6
Original line number Diff line number Diff line
@@ -709,8 +709,8 @@ prog_dump(struct bpf_prog_info *info, enum dump_mode mode, 
	char func_sig[1024];

	unsigned char *buf;

	__u32 member_len;

	int fd, err = -1;

	ssize_t n;

	int fd;



	if (mode == DUMP_JITED) {

		if (info->jited_prog_len == 0 || !info->jited_prog_insns) {
@@ -749,7 +749,7 @@ prog_dump(struct bpf_prog_info *info, enum dump_mode mode, 
		if (fd < 0) {

			p_err("can't open file %s: %s", filepath,

			      strerror(errno));

			return -1;

			goto exit_free;

		}



		n = write(fd, buf, member_len);
@@ -757,7 +757,7 @@ prog_dump(struct bpf_prog_info *info, enum dump_mode mode, 
		if (n != (ssize_t)member_len) {

			p_err("error writing output file: %s",

			      n < 0 ? strerror(errno) : "short write");

			return -1;

			goto exit_free;

		}



		if (json_output)
@@ -771,7 +771,7 @@ prog_dump(struct bpf_prog_info *info, enum dump_mode mode, 
						     info->netns_ino,

						     &disasm_opt);

			if (!name)

				return -1;

				goto exit_free;

		}



		if (info->nr_jited_func_lens && info->jited_func_lens) {
@@ -866,9 +866,12 @@ prog_dump(struct bpf_prog_info *info, enum dump_mode mode, 
		kernel_syms_destroy(&dd);

	}



	btf__free(btf);

	err = 0;



	return 0;

exit_free:

	btf__free(btf);

	bpf_prog_linfo__free(prog_linfo);

	return err;

}



static int do_dump(int argc, char **argv)