From: Jiri Olsa <jolsa@kernel.org>
To: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: dwarves@vger.kernel.org, bpf@vger.kernel.org,
Alexei Starovoitov <ast@kernel.org>,
Andrii Nakryiko <andriin@fb.com>, Yonghong Song <yhs@fb.com>,
Hao Luo <haoluo@google.com>, Sedat Dilek <sedat.dilek@gmail.com>,
Tom Stellard <tstellar@redhat.com>
Subject: [PATCHv2] btf_encoder: Add extra checks for symbol names
Date: Wed, 13 Jan 2021 11:25:09 +0100 [thread overview]
Message-ID: <20210113102509.1338601-1-jolsa@kernel.org> (raw)
When processing kernel image build by clang we can
find some functions without the name, which causes
pahole to segfault.
Adding extra checks to make sure we always have
function's name defined before using it.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
v2 changes:
- reorg the code based on Andrii's suggestion
btf_encoder.c | 13 +++++++++++--
1 file changed, 11 insertions(+), 2 deletions(-)
diff --git a/btf_encoder.c b/btf_encoder.c
index 333973054b61..5557c9efd365 100644
--- a/btf_encoder.c
+++ b/btf_encoder.c
@@ -68,10 +68,14 @@ static int collect_function(struct btf_elf *btfe, GElf_Sym *sym)
struct elf_function *new;
static GElf_Shdr sh;
static int last_idx;
+ const char *name;
int idx;
if (elf_sym__type(sym) != STT_FUNC)
return 0;
+ name = elf_sym__name(sym, btfe->symtab);
+ if (!name)
+ return 0;
if (functions_cnt == functions_alloc) {
functions_alloc = max(1000, functions_alloc * 3 / 2);
@@ -94,7 +98,7 @@ static int collect_function(struct btf_elf *btfe, GElf_Sym *sym)
last_idx = idx;
}
- functions[functions_cnt].name = elf_sym__name(sym, btfe->symtab);
+ functions[functions_cnt].name = name;
functions[functions_cnt].addr = elf_sym__value(sym);
functions[functions_cnt].sh_addr = sh.sh_addr;
functions[functions_cnt].generated = false;
@@ -731,8 +735,13 @@ int cu__encode_btf(struct cu *cu, int verbose, bool force,
continue;
if (functions_cnt) {
struct elf_function *func;
+ const char *name;
+
+ name = function__name(fn, cu);
+ if (!name)
+ continue;
- func = find_function(btfe, function__name(fn, cu));
+ func = find_function(btfe, name);
if (!func || func->generated)
continue;
func->generated = true;
--
2.26.2
next reply other threads:[~2021-01-13 10:26 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-13 10:25 Jiri Olsa [this message]
2021-01-13 17:20 ` [PATCHv2] btf_encoder: Add extra checks for symbol names Yonghong Song
2021-01-13 18:27 ` Jiri Olsa
2021-01-14 7:45 ` Sedat Dilek
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