diff mbox series

[bpf-next,3/3] libbpf: cleanup linker_append_elf_relos

Message ID c5c8fe9f411b69afada8399d23bb048ef2a70535.1677658777.git.vmalik@redhat.com (mailing list archive)
State Accepted
Commit 4672129127eed0d16ab1b4b70b4e49014e49e8bb
Delegated to: BPF
Headers show
Series libbpf: fix several issues reported by static analysers | expand

Checks

Context Check Description
bpf/vmtest-bpf-next-PR success PR summary
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for bpf-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 0 this patch: 0
netdev/cc_maintainers warning 1 maintainers not CCed: llvm@lists.linux.dev
netdev/build_clang success Errors and warnings before: 0 this patch: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 0 this patch: 0
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 34 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
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Commit Message

Viktor Malik March 1, 2023, 8:53 a.m. UTC 
Clang Static Analyser (scan-build) reports some unused symbols and dead
assignments in the linker_append_elf_relos function. Clean these up.

Signed-off-by: Viktor Malik <vmalik@redhat.com>
---
 tools/lib/bpf/linker.c | 11 ++---------
 1 file changed, 2 insertions(+), 9 deletions(-)
diff mbox series

Patch

diff --git a/tools/lib/bpf/linker.c b/tools/lib/bpf/linker.c
index 4ac02c28e152..d7069780984a 100644
--- a/tools/lib/bpf/linker.c
+++ b/tools/lib/bpf/linker.c
@@ -1997,7 +1997,6 @@  static int linker_append_elf_sym(struct bpf_linker *linker, struct src_obj *obj,
 static int linker_append_elf_relos(struct bpf_linker *linker, struct src_obj *obj)
 {
 	struct src_sec *src_symtab = &obj->secs[obj->symtab_sec_idx];
-	struct dst_sec *dst_symtab;
 	int i, err;
 
 	for (i = 1; i < obj->sec_cnt; i++) {
@@ -2030,9 +2029,6 @@  static int linker_append_elf_relos(struct bpf_linker *linker, struct src_obj *ob
 			return -1;
 		}
 
-		/* add_dst_sec() above could have invalidated linker->secs */
-		dst_symtab = &linker->secs[linker->symtab_sec_idx];
-
 		/* shdr->sh_link points to SYMTAB */
 		dst_sec->shdr->sh_link = linker->symtab_sec_idx;
 
@@ -2049,16 +2045,13 @@  static int linker_append_elf_relos(struct bpf_linker *linker, struct src_obj *ob
 		dst_rel = dst_sec->raw_data + src_sec->dst_off;
 		n = src_sec->shdr->sh_size / src_sec->shdr->sh_entsize;
 		for (j = 0; j < n; j++, src_rel++, dst_rel++) {
-			size_t src_sym_idx = ELF64_R_SYM(src_rel->r_info);
-			size_t sym_type = ELF64_R_TYPE(src_rel->r_info);
-			Elf64_Sym *src_sym, *dst_sym;
-			size_t dst_sym_idx;
+			size_t src_sym_idx, dst_sym_idx, sym_type;
+			Elf64_Sym *src_sym;
 
 			src_sym_idx = ELF64_R_SYM(src_rel->r_info);
 			src_sym = src_symtab->data->d_buf + sizeof(*src_sym) * src_sym_idx;
 
 			dst_sym_idx = obj->sym_map[src_sym_idx];
-			dst_sym = dst_symtab->raw_data + sizeof(*dst_sym) * dst_sym_idx;
 			dst_rel->r_offset += src_linked_sec->dst_off;
 			sym_type = ELF64_R_TYPE(src_rel->r_info);
 			dst_rel->r_info = ELF64_R_INFO(dst_sym_idx, sym_type);