[PATCH] lib: bpf: Optimized variable usage in the btf_parse_elf function

From: Li kunyu
Date: Sun Oct 09 2022 - 03:09:51 EST


The following changes were made in the btf_parse_elf function:
1. The initialization assignments of err, fd, scn and elf variables are
removed, and they do not affect function security after analysis.
2. Remove unnecessary assignments to err variable (-error).

Signed-off-by: Li kunyu <kunyu@xxxxxxxxxxxx>
---
tools/lib/bpf/btf.c | 11 ++++-------
1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/tools/lib/bpf/btf.c b/tools/lib/bpf/btf.c
index 2d14f1a52d7a..fa9d5fa03da4 100644
--- a/tools/lib/bpf/btf.c
+++ b/tools/lib/bpf/btf.c
@@ -910,10 +910,10 @@ static struct btf *btf_parse_elf(const char *path, struct btf *base_btf,
struct btf_ext **btf_ext)
{
Elf_Data *btf_data = NULL, *btf_ext_data = NULL;
- int err = 0, fd = -1, idx = 0;
+ int err, fd, idx = 0;
struct btf *btf = NULL;
- Elf_Scn *scn = NULL;
- Elf *elf = NULL;
+ Elf_Scn *scn;
+ Elf *elf;
GElf_Ehdr ehdr;
size_t shstrndx;

@@ -924,9 +924,8 @@ static struct btf *btf_parse_elf(const char *path, struct btf *base_btf,

fd = open(path, O_RDONLY | O_CLOEXEC);
if (fd < 0) {
- err = -errno;
pr_warn("failed to open %s: %s\n", path, strerror(errno));
- return ERR_PTR(err);
+ return ERR_PTR(-errno);
}

err = -LIBBPF_ERRNO__FORMAT;
@@ -987,8 +986,6 @@ static struct btf *btf_parse_elf(const char *path, struct btf *base_btf,
}
}

- err = 0;
-
if (!btf_data) {
err = -ENOENT;
goto done;
--
2.18.2