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From: Quentin Monnet <quentin@isovalent.com>
Date: Wed, 10 Nov 2021 11:46:27 +0000
Subject: bpftool: Fix memory leak in prog_dump()
Patch-mainline: v5.17-rc1
Git-commit: ebbd7f64a3fbe9e0f235e39fc244ee9735e2a52a
References: git-fixes

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: ec2025095cf6 ("bpftool: Match several programs with same tag")
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211110114632.24537-2-quentin@isovalent.com
Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
---
 tools/bpf/bpftool/prog.c |   15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

--- a/tools/bpf/bpftool/prog.c
+++ b/tools/bpf/bpftool/prog.c
@@ -628,8 +628,8 @@ prog_dump(struct bpf_prog_info *info, en
 	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) {
@@ -665,7 +665,7 @@ prog_dump(struct bpf_prog_info *info, en
 		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);
@@ -673,7 +673,7 @@ prog_dump(struct bpf_prog_info *info, en
 		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)
@@ -687,7 +687,7 @@ prog_dump(struct bpf_prog_info *info, en
 						     info->netns_ino,
 						     &disasm_opt);
 			if (!name)
-				return -1;
+				goto exit_free;
 		}
 
 		if (info->nr_jited_func_lens && info->jited_func_lens) {
@@ -782,9 +782,12 @@ prog_dump(struct bpf_prog_info *info, en
 		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)