diff mbox series

[bpf-next,v2,2/3] libbpf: deal with section with no data gracefully

Message ID 20221012022353.7350-3-shung-hsi.yu@suse.com (mailing list archive)
State Accepted
Commit 662e24598d8c19e82cb92b6d85d7ba2d612b92fe
Delegated to: BPF
Headers show
Series libbpf: fix fuzzer-reported issues | expand

Checks

Context Check Description
netdev/tree_selection success Clearly marked for bpf-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/subject_prefix success Link
netdev/cover_letter success Series has a cover letter
netdev/patch_count success Link
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 fail 2 blamed authors not CCed: acme@redhat.com wangnan0@huawei.com; 2 maintainers not CCed: acme@redhat.com wangnan0@huawei.com
netdev/build_clang success Errors and warnings before: 0 this patch: 0
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success Fixes tag looks correct
netdev/build_allmodconfig_warn success Errors and warnings before: 0 this patch: 0
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 18 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
bpf/vmtest-bpf-next-PR fail PR summary
bpf/vmtest-bpf-next-VM_Test-1 success Logs for build for s390x with gcc
bpf/vmtest-bpf-next-VM_Test-6 success Logs for test_maps on s390x with gcc
bpf/vmtest-bpf-next-VM_Test-7 success Logs for test_maps on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-12 success Logs for test_progs_no_alu32 on s390x with gcc
bpf/vmtest-bpf-next-VM_Test-13 fail Logs for test_progs_no_alu32 on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-14 fail Logs for test_progs_no_alu32 on x86_64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-16 success Logs for test_verifier on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-17 success Logs for test_verifier on x86_64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-8 success Logs for test_maps on x86_64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-9 success Logs for test_progs on s390x with gcc
bpf/vmtest-bpf-next-VM_Test-10 fail Logs for test_progs on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-11 fail Logs for test_progs on x86_64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-15 success Logs for test_verifier on s390x with gcc
bpf/vmtest-bpf-next-VM_Test-2 success Logs for build for x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-3 success Logs for build for x86_64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-4 success Logs for llvm-toolchain
bpf/vmtest-bpf-next-VM_Test-5 success Logs for set-matrix

Commit Message

Shung-Hsi Yu Oct. 12, 2022, 2:23 a.m. UTC 
ELF section data pointer returned by libelf may be NULL (if section has
SHT_NOBITS), so null check section data pointer before attempting to
copy license and kversion section.

Fixes: cb1e5e961991 ("bpf tools: Collect version and license from ELF sections")
Signed-off-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
---
 tools/lib/bpf/libbpf.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

--
2.37.3
diff mbox series

Patch

diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 2e8ac13de6a0..29e9df0c232b 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -1408,6 +1408,10 @@  static int bpf_object__check_endianness(struct bpf_object *obj)
 static int
 bpf_object__init_license(struct bpf_object *obj, void *data, size_t size)
 {
+	if (!data) {
+		pr_warn("invalid license section in %s\n", obj->path);
+		return -LIBBPF_ERRNO__FORMAT;
+	}
 	/* libbpf_strlcpy() only copies first N - 1 bytes, so size + 1 won't
 	 * go over allowed ELF data section buffer
 	 */
@@ -1421,7 +1425,7 @@  bpf_object__init_kversion(struct bpf_object *obj, void *data, size_t size)
 {
 	__u32 kver;

-	if (size != sizeof(kver)) {
+	if (!data || size != sizeof(kver)) {
 		pr_warn("invalid kver section in %s\n", obj->path);
 		return -LIBBPF_ERRNO__FORMAT;
 	}