netdev - [PATCH bpf-next] libbpf: emit diff of mismatched public API, if any

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:   Wed, 22 May 2019 09:15:20 -0700
From:   Andrii Nakryiko <andriin@...com>
To:     <andrii.nakryiko@...il.com>, <netdev@...r.kernel.org>,
        <bpf@...r.kernel.org>, <ast@...com>, <daniel@...earbox.net>
CC:     Andrii Nakryiko <andriin@...com>
Subject: [PATCH bpf-next] libbpf: emit diff of mismatched public API, if any

It's easy to have a mismatch of "intended to be public" vs really
exposed API functions. While Makefile does check for this mismatch, if
it actually occurs it's not trivial to determine which functions are
accidentally exposed. This patch dumps out a diff showing what's not
supposed to be exposed facilitating easier fixing.

Signed-off-by: Andrii Nakryiko <andriin@...com>
---
 tools/lib/bpf/.gitignore | 2 ++
 tools/lib/bpf/Makefile   | 8 ++++++++
 2 files changed, 10 insertions(+)

diff --git a/tools/lib/bpf/.gitignore b/tools/lib/bpf/.gitignore
index d9e9dec04605..c7306e858e2e 100644
--- a/tools/lib/bpf/.gitignore
+++ b/tools/lib/bpf/.gitignore
@@ -3,3 +3,5 @@ libbpf.pc
 FEATURE-DUMP.libbpf
 test_libbpf
 libbpf.so.*
+libbpf_global_syms.tmp
+libbpf_versioned_syms.tmp
diff --git a/tools/lib/bpf/Makefile b/tools/lib/bpf/Makefile
index f91639bf5650..7e7d6d851713 100644
--- a/tools/lib/bpf/Makefile
+++ b/tools/lib/bpf/Makefile
@@ -204,6 +204,14 @@ check_abi: $(OUTPUT)libbpf.so
 		     "versioned symbols in $^ ($(VERSIONED_SYM_COUNT))." \
 		     "Please make sure all LIBBPF_API symbols are"	 \
 		     "versioned in $(VERSION_SCRIPT)." >&2;		 \
+		readelf -s --wide $(OUTPUT)libbpf-in.o |		 \
+		    awk '/GLOBAL/ && /DEFAULT/ && !/UND/ {print $$8}'|   \
+		    sort -u > $(OUTPUT)libbpf_global_syms.tmp;		 \
+		readelf -s --wide $(OUTPUT)libbpf.so |			 \
+		    grep -Eo '[^ ]+@...BPF_' | cut -d@ -f1 |		 \
+		    sort -u > $(OUTPUT)libbpf_versioned_syms.tmp; 	 \
+		diff -u $(OUTPUT)libbpf_global_syms.tmp			 \
+		     $(OUTPUT)libbpf_versioned_syms.tmp;		 \
 		exit 1;							 \
 	fi
 
-- 
2.17.1